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Home My WebLink AboutAPA1936..... ~ ! ALASKA DEPARTMENT OF FISH AND GAME SUSITNA HYDRO AQUATIC STUDIES REPORT SERIES - """ -I T~ /L/JS rS3 AfoTt no-[q36 ALASKA DEPARTMENT OF FISH AND GAME SUSITNA HYDRO AQUATIC STUDIES REPORT NO.3 AQUATIC HABITAT AND INSTREA,M FLOW INVESTIGATIONS (MAY-OCTOBER 1983) Chapter 7:An Evaluation of Chum and Sockeye Salmon Spawning Habitat in Sloughs and Side Channels'of the Middle Susltna River Edited by: Christopher C.Estes and Douglas S.Vincent-Lang Prepared for: ALASKA POWER AUTHORITY 334 W.FIFTH AVE. ANCHORAGE.ALASKA 99501 ARLIS Alaska Resources Library &InformatIon ServiceS .Anchorage.Alaska .- ..... PREFACE This report is one of a series of reports prepared for th~Alaska Power Authority (APA)by the Alaska Department of Fish and Game (ADF&G)to provide information to be used in evaluating the feasibility of the proposed Susitna Hydroelectric Project.The ADF&G Susitna Hydro Aquatic Studies program was initiated ·in November 1980.The five year study program was divided into three study sections:Adult Anadromous Fish Studies (AA),Resident and Juvenile Anadromous Studies (RJ).and Aquatic Habitat and Instream Flow Studies (AH).Reports prepared by the ADF&G prior to 1983 on this subject are available from the APA. The information in this report summarizes the findings of the 1983 open water field season investigations.Beginning with the 1983 reports.all reports were sequentially numbered as part of the Alaska Department of Fish and Game Susitna Hydro Aquatic Studies Report Series. TITLES IN THE 1983 SERIES Report Number 1 2 !""" 3 4 Publ ication Title Date----- Adult Anadromous Fish Investigations:April 1984 May -October 1983 Resident and Juvenile Anadromous Fish July 1984 Investigations:May -October 1983 Aquatic Habitat and Instream Flow Sept 1984 Investigations:May -October 1983 Access and Transmission Corridor Aquatic Sept 1984 Investigations:May -October 1983 This report."Aquatic Habitat and Instream Flow Investigations"is divided into two parts.Part I,the "Hydrologic and Water Qual ity Investigations".is a compilation of the physical and chemical data collected by th AOF&G Su Hydro Aquatic Studies team during 1983.These data are arranged by individual variables and geographic location for ease of access to user agencies.The combined data set represents the available physical habitat of the study area within the Cook Inlet to Oshetna River reach of the Susitna River.Part II,the "Adult Anadro- mous Fish Habitat Investigations".describes the subset of available habitat compiled in Part 1 that,is utilized by adult anadromous fish studied in the middle and lower Susitna River (Cook Inlet to Devil Canyon)study area.The studies primarily emphasize the utilization of side slough and side channel habitats of the middle reach of the Susitna River for spawning (Figure A).It represents the first stage of development for an instream flow relationships analysis report which will be prepared by £.W.Trihey and Associates. ARLIS Alaska Resources Library &Informatlon SetV1ce~ Anchorage.A'a~k8, MID OLE REACH ADF aG FIELD CAMPS OVERALL STUDY AREA-- CJ • , "-.............................................. \ \ \, I I,,, I a/ /1--_......,; o 25 I , mile. "•••.._ill Figure A.Susitna River draina~e basin. "J 1 ...J )I I .1 I I .J ....J J I J t - - CONTENTS OF REPORT NO.3 Part One Chapter 1 Stage and Discharge Investigations. 2 Channel Geometry Investigations. 3 Continuous Water Temperature Investigations. 4 Water Quality Investigations. Part Two Chapter 5 Eulachon Spawning in the Lower Susitna River. 6 An Evaluation of Passage Conditions for Adult Salmon in Sloughs and Side Channels of the Middle Susitna River. 7 An Evaluation of Chum and Sockeye Salmon Spawning Habitat in Sloughs and Side Channels of the Middle Susitna River . ..- I 8 9 10 An Evaluation of Salmon Spawning Habitat in Selected Tributary Mouth Habitats of the Middle Susitna River. Habitat Suitability Criteria for Chinook.Coho,and Pink Salmon Spawning. The Effectiveness of Infrared Thermal Imagery Techniques for Detecting Upwelling Groundwater. ...... ...... M........-o:to:t 0 0 0 LO LO ן""'- M M ~ - Questions concerning this and prior reports should be directed to: Alaska Power Authority 334 W.5th Avenue Anchorage.Alaska 99501 Telephone (907)276-0001 - - AN EVALUATION OF CHUM AND SOCKEYE SALMON SpAWNING HABITAT IN SLOUGHS AND SIDE CHANNELS OF THE MIDDLE SUSITNA RIVER 1984 Report No.3,Chapter 7 By: Doug Vincent-Lang, Andrew Hoffmann, Allen E.Bingham,and Christopher Estes of Alaska Department Fish and Game Susitna Hydro Aquatic Studies 2207 Spenard Road Anchorage,Alaska 99503 And Diane Hilliard,Cleveland Stewart,and E.Woody Trihey of E.Woody Trihey and Associates And Steve Crumley of Woodward Clyde Consultants ABSTRACT Three sloughs (8A,9,and 21)and four side channels (10,Lower 11, Upper 11,and 21)in the.middle reach of the Susitna River were evaluated using an Instream Flow Incremental Methodology (IFIM)physical habitat simulation (PHABSIM)modelling approach to evaluate the effects that site flow and mainstem discharge have on chum and sockeye salmon spawning habitat usability.Based in available field data,spawning habitat conditions on these sloughs and side channels are thought to represent the range of spawning habitat conditions that are present in the sloughs and side channels of the middle Susitna River which currently support a majority of chum and sockeye salmon spawning in these habitat types. i Ten hydraulic simulation models were calibrated to simulate depths and velocities associated with a range of site-specific flows at these seven modelling study sites.Comparisons between corresponding sets of simulated and measured depths and velocities indicate that the calibrated models provide reliable est"imates of depths and velocities within their recommended calibration ranges. Habitat suitability criteria for chum and sockeye salmon spawning for the habitat variables of depth,velocity,substrate,and upwelling were developed for input into a habitat simulation model.The suitability criteria developed for chum salmon spawning were based on an analysis of utilization data as modified using limited preference data,literature information,and the opinion of project biologists familiar with middle Susitna River chum salmon stocks.The spawning suitability criteria constructed for sockeye salmon were developed using the same analytical approach used in the chum salmon analysis with the exception that no analysis of preference could be made. Using a habitat simulation model (HABTAT),the output of hydraulic simulation models and the spawning habitat suitability criteria were linked to project usable area of chum and sockeye salmon spawning habitat (WUA)as a function of flow for each of the seven modelled study sites.Using these relationships and relationships between site flows and mainstem discharge presented in Chapter 1 of this report,the relationships between chum and sockeye salmon spawning habitat as a function of mainstem discharge for the period of controlled site flows were also determined for each modelled study site.These projections of chum and sockeye spawning WUA made at study sites indicate that spawning habitat usability in sloughs and side channels exhibits certain speci es-specifi c and s ite-specifi c trends .Generally,projecti ons of WUA at study sites peak in the range mainstem discharges from 20,000 to 35,000 cfs,with the controlling factor appearing to be the overtopping of the site by mainstem discharge and the subsequent control of the site flow by mainstem discharge.Assuming that the modelled sloughs and side channels are representative of other non-modelled sloughs and side channels in the middle reach which currently support spawning,the theoretical maximum WUA for slough and side channel habitats in the middle river reach would occur slightly after the mainstem discharge overtops and control s the hydraul i cs at a maximum number of these habitats.Based on a revi ew of time series plots of WUA overtime of each study site,however,flows at study sites which currently support chum and sockeye spawning are only infrequently controlled by mainstem discharge.For this reason,the WUA at study sites remains relatively low and stable during the period of peak spawning activity (August through September),except during flood events.There appears to be a general positive correlation between projected WUA and habitat use at study sites. i i -. - - - - - - TABLE OF CONTENTS PREFACE 011 e"'"f)0 .. ABSTRACT G III 011 ..e III 8"..; TABLE OF CONTENTS ill 08 .. .. .. .. .. .. ..;;; LIST OF FIGURES.................................................vii LIST OF APPENDIX FIGURES ....•...•....••...•.•...........•.......xvi LIST OF TABLES ,.............................................xv;;; LIST OF APPENDIX TABLES.........................................xxi LIST OF PLATES...................................................................................................xv FOREWARD 7-F-l .... 1.0 GENERAL INFORMATION ".. 1.1 Background and Objectives .........•......•••.......... 1.2 Study Approach . 1.3 Previous Studies . 2.0 STUDY SITE SELECTION ....•..•.......•.....•...............•. 2.1 Study Site Selection Concepts .•.....•..•.............. 2.2 Study Site Selection . 2.2.1 Slough Study Sites .....•....................... 2.2.2 Side Channel Study Sites ..•.......•..•......... 2.3 Study Site Descriptions .•..•................•......... 3.0 HYDRAULIC SIMULATION MODELS •.•..•.....••..........•......•. 3.1 Introduction . 3.2 Me·t.hods •••••••••••••••••••••••••••••••••••••••••••••.•• 3.2.1 Analytical Approach .••..............•......•... 3.2.2 General Techniques for Data Collection .•...•... 3.2.3 General Techniques for Calibration •....•....... 3.2.4 General Techniques for Verification ....•...•... 3.3 Resul ts .........................•..................... 3.3.1 Slough 8A ·. 3.3.1.1 Site Description ...•..•............... 3.3.1.2 Data Collected . 3.3.1.3 Calibration . 3.3.1.4 Verification . 3.3.1.5 Application . iii 7-1-1 7-1-1 7-1-3 7-1-4 7-2-1 7-2-1 7-2-1 7-2-1 7-2-6 7-2-7 7-3-1 7-3-1 7-3-1 7-3-1 7-3-3 7-3-5 7-3-6 7-3-9 7-3-9 7-3-9 7-3-9 7-3-13 7-3-13 7-3-18 TABLE OF CONTENTS (continued) 4.3.1.2 Velocity Spawning Suitability Criteria 7-4-21 4.3.1.3 Substrate Spawning Suitability Cr;teri a 7-4-28 4.0 FISH HABITAT CRITERIA ANALySIS . 4.1 Introduction . 4.2 Methods "•........•................. ~, ~I I - - - - - pa~e 7-3-0 7-3-20 7-3-20 7-3-21 7-3-26 7-3-30 7-3-30 7-3-30 7-3-32 7-3-32 7-3-37 7-3-37 7-3-40 7-3-40 7-3-40 7-3-42 7-3-42 7-3-47 7-3-47 7-3-47 7-3-47 7-3-49 7-3-51 7-3-51 7-3-55 7-3-55 7-3-55 7-3-57 7-3-57 7-3-62 7-3-62 7-3-62 7-3-62 7-3-64 7-3-67 7-3-73 7-3-73 7-4-1 7-4-1 7-4-1 7-4-1 7-4-2 7-4-4 7-4-14 7-4-14 7-4-16 3.3.3.4 Verification . 4.3.1.1 Depth Spawning Suitablility Cri teri a . 3.3.3.1 Site Description ........•......••..... 3.3.3.2 Data Collected ..................•..•.. 3.3.3.3 Calibration ............•..•........... 3•3•2 S1au 9h 9 ...<•••••••••••••••••••••••••••••••••••• 3.3.2.1 Site Description •......•....•.....•••. 3.3.2.2 Da ta Co 11 ected •..•........•.....••.•.• 3.3.2.3 Calibration.o.6 •••oo ••••••~••••••••••• 3.3.204 Verification ..•.....•...........o ••••• 3.3.2.5 Application e ••••••• 3.3.3 Slough 21 . 3.3.3.5 Application .........................•. 3.3.4 Side Channel 10 .....•.......................... 3.3.4.1 Site Description •..................... 3.3.4.2 Da ta Co 11 ec ted .............•.......... 3.3.4.3 Calibration ..........•..........•..... 3.3.4.4 Verification ............•..........•.. 3.3.4.5 Application ...............•........... 3.3.5 Lower Side Channel 11 ........•.........•....... 3.3.5.1 Site Description . 3.3.5.2 Data Collected . 3.3.5.3 Calibration ....•.....•..........•..... 3.3.5.4 Verification . 3.3.5.5 Application . 3.3.6 U~per Side Channel 11 ................•.....•... 3.3.6.1 Site Description ........•..•.......... 3.3.6.2 Data Collected ....•................... 3.3.6.3 Calibration .....•.•.....•............. 3.3.6.4 Verification •........••......•........ 3.3.6.5 Application ..........•................ 3.3.7 Side Channel 21 ....•........................•.. 3.3.7.1 -Site Description ..••.................. 3.3.7.2 Data Collected . 3.3.7.3 Calibration ........•.................. 3.3.7.4 Verification . 3.3.7.5 Application . Discussion . 4.2.1 Site Selection . 4.2.2 Field Data Collection . 4.2.3 Analytical Approach •.•..•..•...•..•............ 4.3 Results . 4.3.1 Chum Salmon . 3.4 iv TABLE OF CONTENTS (continued) 4.3.1.4 Upwelling Spawning Suitablility Criteria ..o ••••••••••••••••••••••••••• Page 7-4-32 - -- 4.3.1.5 Combined Substrate/Upwelling Spawning Suitablilty Criteria ...•.•......••....7-4-32 4.3.1.6 Statistical Independence of Habitat Variables Evaluated ••....•..•....•....7-4-32 4.-3.2 Sockeye Salmon 7-4-32 4.3.2.1 Depth Spawning Suitability Criteria .•.7-4-32 4.3.2.2 Velocity Spawning Suitability Criteria 7-4-37 4.3.2.3 Substrate Spawning Suitability Criteria ..••..•.~e ••••••e ••••7-4-44 4.2.3.4 Upwelling Spawning Suitability Criteria 7-4-48 4.2.3.5 Combined Substrate/Upwelling Spawning Suitability Criteria ....•...7-4-50 4.2.3.6 Statistical Independence of Habitat . Variables Evaluated ;7-4-50 4.4 Discussion 7-4-50 4.4.1 Assumptions and Limitations of the Data Base 7-4-50 4.4.2 Suitability Criteria ..................•........7-4-55 4.4.2.1 Chum Salmon 7-4-55 4.4.2.2 Sockeye Salmon .•..........•....•......7-4-56 4.4.3 Recommended Applications and Limitations of the Suitabil ity Criteri a 7-4-56 5.0 SPAWNING HABITAT PROJECTIONS...............................7-5-1 5.1 Introduction 7-5-1 5.2 Methods 7-5-1 5.2.1 Analytical Approach and Methodology •....•.......7-5-1 5.2.2 Model Validation 7-5-4 5.3 Results 7-5-7 5.3.1 Weighted Usable Area Projections 7-5-7 5.3.1.1 Chum Salmon 7-5-7 5.3.1.2 Sockeye Salmon ..............•.......•.7-5-14- 5.3.2 Model Validation ..•..•.......•..•.:7-5-26 5.4 Discussion 7-5-45 5.4.1 Assumptions used in the Application of the Habitat Simulation Models •...........•......7-5-45 5.4.2 Weighted Usable Area Projections •..............7-5-47 5.4.3 Recommended Applications and Limitations of the Data 7-5-48 6.0 SUMMARy....................................................7-6-1 7•0 GLOS SA RY .. . .. . .. . .. ... . . . .. . .•. . . . . . . . .. . . .. . .. . ... . . . .. . .. 7-7-1 8.0 CONTRIBUTORS 7-8-1 9.0 ACKNOWLEDGEMENTS 7-9-1 v TABLE OF CONTENTS (continued) 10.0 LI-rERATURE CITED ••.•.•....o ••••e •••••••••••••e •••••••••••••7-10-1 11.0 APPENDICES o ••e ••••••••••••••••e ••••IIl •••••.e 7-11-1 - Appendix 7-A: Appendix 7-8: Appendix 7-C: Appendix 7-D: Appendix 7-E: Calibration Data and Scatter Plots for Hydraulic Simulation Models ..........•......7-A-1 Salmon Spawning Utilization Data 7-8-1 Summary of Statistics and Tests for Various .. Groupings of Chum and Sockeye Salmon .......•. Utilization Historgrams 7-C-1 Weighted Usable Area Projection Data ......•..7-0-1 Flow Chart and Outline of Salmon Habitat ..... Analysis o ••e •••••••••••••7-E-1 vi - - - - - - LIST OF FIGURES Figure Section 1.0 7-1-1 General habitat categories of the middle Susitna River - a conceptual diagram (ADF&G 1983)..•....•..••.7-1-2 Section 2.0 r I I .""" 7-2-1 7-2-2 7-2-3 7-2-4 7-2-5 7-2-6 7-2-7 7-2-8 7-2-9 7-2-10 7-2-11 7-3-1 Middle river study sites evaluated using the IFIM PHABSIM modelling system ............•..•..............7-2-8 Flow duration curves for the months of August and September for the years 1981,1982,and 1983 and the 30 year historical discharge composite record depicting discharge for the modelled study sites 7-2-12 Chum salmon spawning areas,Slough 8A,1981,1982, 1983 II 7-2-13 Sockeye salmon spawning areas,Slough 8A,1981, 1982,1983 7-2-14 Chum salmon spawning areas,Slough 9,1981,1982, 1983 7-2-17 Sockeye salmon spawning areas,Slough 9,1982 and 1983 7 -2-18 Chum salmon spawning areas,Slough 21,1981,1982, 1983 7-2-21 Sockeye salmon spawning areas,Slough 21,1981, 1982, 1983 7-2-22 Chum salmon spawning areas,Upper Side Channel 11, 1981,1982,1983 ....................................•.7-2-27 Chum salmon spawning areas,Side Channel 21,1981, 1982,1983 7-2-30 Sockeye salmon spawning areas,Side Channel 21,1982 1982 and 1983 ......................•..................7-2-31 Section 3.0 Flow chart for comparing model predicted water surface elevations with site specific water surface elevations-versus-discharge curves developed by ADF&G.. . . . •. . . . . . . . . . . . . . . •. . . . . . . . . . . . . . . . . . . . . . . . •. 7-3'-7 7-3-2 Cross sections for Slough 8A study site depicting water surface ele~atiQns at calibration dischargesat4,7,19,and 53 ct-s ....•...•...••......•..........7-3-10 vii LIST OF FIGURES (continued) Figure ,P>1I 7-3-3 7-3-4 7-3-5 7-3-6 7-3-7 7-3-8 7-3-9 7-3-10 7-3-11 7-3-12 7-3-13 7-3-14 7-3-15 Comparison of observed and predicted water surface profiles from non-calibrated model at Slough 8A study site GO Ill II."011 ••••••7-3-14 Comparison of observed and predicted water surface profiles from non-calibrated model at Slough 8A study site 7-3-15 Comparison of observed and predicted water surface profiles from calibrated model at Slough 8A study site for low flow regime ....•....•.•..................7-3-16 Comparison of observed and predicted water surface profiles from calibrated model at Slough 8A study site for high flow regime •...................•........7-3-17 Comparison between ADF&G rating curve and model predicted water surface elevations 7-3-19 Cross sections for Slough 9 study site depicting water surface elevations at calibration discharges of 8,89,148,and 232 cfs 7-3-22 Comparison of observed and predicted water surface profiles from non-calibrated model at Slough 9 study site 7-3-24 Comparison between 1982 and 1983 streambed and water surface profiles at Slough 9 study site •........7-3-25 Comparison of observed and predicted water surface profiles from calibrated model at Slough 9 study site 7-3-27 Relationship between extrapolation range of the Slough 9 model and ADF&G flow-versus-discharge curve 7-3-28 Comparison between ADF&G rating curve and model predicted water surface elevations ...~•...............7-3-29 Cross sections for Slough 21 study site depicting water surface elevations at calibration discharges 5,10,74 and 157 cfs 7-3-31 Comparison of observed and predicted water surface profiles from non-calibrated model at Slough 21 study site 7-3-33 viii - - - '""" - LIST OF FIGURES (continued) Figure 7-3-16 7-3-17 7-3-22 7-3-23 7-3-24 7-3-25 7-3-26 7-3-27 7-3-28 7-3-29 Comparison of observed and predicted water surface profiles from non-calibrated model at Slough 21 study 5;te "7-3-34 Comparison of observed and predicted water surface profiles from calibrated model at Slough 21 study site for low flow regimes ..•.•..•..•..••....•...•...•.7-3-35 Comparison of observed and predicted water surface profiles for calibrated model at Slough 21 study site for high flow regime •..••.•...•..•••.••....••.•..7-3-36 Relationship between extrapolation range of Slough 21 low and high flow models and ADF&G flow-versus-discharge curve .....••.••••••.....•••..•..7-3-38 Comparison between ADF&G rating curve and model predicted water surface elevations .•......••....•.•...7-3-39 Cross sections for Side Channel 10 study site depicting water surface elevations at calibration discharges of 8 and 80 cfs .•.....•....•..•............7-3-41 Comparison of observed and predicted water surface profiles from non-calibrated model at Side Channel 10 study site 7-3-43 Comparison of observed and predicted water surface profiles from calibrated model at Side Channel 10 study site 7-3-44 Relationship between extrapolation range of Side Channel 10 model and ADF&G flow-versus-discharge curve 7-3-45 Comparison between ADF&G rating curve and model predicted water surface elevations .••.•.••......•..•..7-3-46 Cross sections for Lower Side Channel 11 study site depicting water surface elevations at calibration di scha rge of 820 cfs 7 -3-48 Comparison between measured and adjusted cross sections 1 and 3 for Lower Side Channel 11 study site 7-3-50 Comparison of observed and predicted water surface profiles from calibrated model at Lower Side Channel 11 study site 7-3-52 Relationship between extrapolation range of LowerSideChannel11modelandADF&G flow-versus- discharge curve ..•..•..•..............•..........•....7-3-53 ix LIST OF FIGURES (continued) Figure 7-3-30 7-3-31 7-3-32 7-3-33 7-3-34 7-3-35 7-3-36 .7-3-37 7-3-38 7-3-39 7-3-40 7-3-41 7-3-42 7-3-43 Comparison between ADF&G rating curve and model predicted water surface elevations .••.....•••.........7-3-54 Cross sections for Upper Side Channel 11 study site depicting water surface profiles at calibration discharges of 12,54,and 110 cfs .••••....•.•..•..•..•7-3-56 Comparison of observed and predicted water surface profiles from non-calibrated model at Upper Side Channel 11 study site •.•.....••.•...•.............•...7-3-58 Comparison of observed and predicted water surface profiles from calibrated model at Upper Side Channel 11 ~tudy site C1 ••••••••••7-3-59 Relationship between extrapolation range of Upper Side Channel 11 model and ADF&G flow-versus- discharge curve ...........................•...........7-3-60 Comparison between ADF&G rating curve and model predicted water surface elevations ..•....•...•........7-3-61 Cross sections for Side Channel 21 study site depicting water surface profiles at calibration discharges of 23,100,431 and 776 cfs 7-3-63 Comparison of observed and predicted water surface profiles from non-calibrated model at Upper Side Channel 21 study site ......•....••..............•.....7-3-65 Comparison of observed and predicted water surface profiles from non-calibrated model at Side Channel 21 study site 7-3-66 Comparison of observed and predicted water surface profiles from non-calibrated model at Side Channel 21 study site 7-3-68 Comparison of observed and predicted water surface profiles from calibrated model at Side Channel 21 study site for low flow regime •........•...•..........7-3-69 Comparison of observed and predicted water surface profiles from calibrated model at Side Channel 21 study site for high flow regime ..............•........7-3-70 R~lationship between extrapolation range of Side Channel 21 low and high flow models and ADF&G flow-versus-discharge curve ...•........•..............7-3-71 Comp,grison between ADF&G rating curve and modelpreolctedwatersurfaceelevatlons....•......•........7-3-72 x - - - - LIST OF FIGURES (continued) Figure Section 4.0 ~, 7-4-1 7-4-2 7-4-3 7-4-4 7-4-5 7-4-6 7-4-7 7-4-8 7-4-9 7-4-10 7-4-11 7-4-12 7-4-13 7-4-14 7-4-15 7-4-16 7-4-17 7-4-18 Side slough and side channel locations where fish habitat criteria data were collected •.•...............7-4-3 Incremental plots of chum salmon spawning depth utilization data .•..•...........•..•..................7-4-17 Best depth utilization curve for chum salmon spawning e _••7-4-19 Depth utilization versus availability for chum salmon spawning used to evaluate preference 7-4-20 Depth suitability curve for chum salmon spawning 7-4-22 Incremental plots of chum salmon spawning velocity utilization data ............................•.........7-4-23 Best velocity utilization curve for chum salmon spawn;ng ..•..........'7-4-25 Velocity utilization versus availability for chum salmon spawning used to evaluate preference 7-4-26 Velocity suitability curve for chum salmon spawning 7-4-27 Substrate utilization curve for chum salmon spawn;ng ....•........•.....•.............•............7-4-29 Substrate utilization versus availability for chum salmon spawning used to evaluate preference 7-4-30 Substrate suitability curve for chum salmon spawn;ng ................•.............................7-4-31 Combined substrate/upwelling SUitability curve for chum salmon spawn;ng .••••••••••••••••••••••.•••••••••••7-4-34 Plots depicting the relationship between utilized depths versus velocities,utilized depths versus substrates,and utilized velocities versus substrates for chum salmon spawning •.......•..........•..•.......7-4-35 Incremental plots of sockeye salmon spawning depth utilization data 7-4-38 Best depth utilization curve for sockeye salmon spawn;ng 7-4-40 Depth suitability curve for sockeye salmon spawning ...7-4-41 Incre~ental p'lpts pf sockeye salmon spawning veloclty utlllZatlon data 7-4-42 xi LIST OF FIGURES (continued) Fi gure 7-4-19 7-4-20 7-4-21 7-4-22 7-4-23 7-4-24 7-5-1 7-5-2 7-5-3 7-5-4 7-5-5 Best velocity utilization curve for sockeye salmon spawning 410 D D II ..""D 'III""D 7-4-45 Velocity suitability curve for sockeye salmon spaw,ning 7-4-46 Substrate utilization curve for sockeye salmon spawning 7-4-47 Substrate suitability curve for sockeye salmon spawning .........................•......................7-4-49 Combined substrate/upwelling suitability curve for sockeye salmon spawning ................•.....•.....•....7-4-52 Plots depicting the relationship between utilized depths versus velocities,utilized depths versus substrates,and utilized velocities versus substrates for sockeye salmon spawning ..•...............7-4-53 Section 5.0 Projections of gross surface area and WUA of chum salmon spawning habitat as a function of site flow and mainstem discharge for the Slough SA modelling site 7-5-8 Projections of gross surface area and WUA of chum salmon spawning habitat as a function of site flow and mainstem discharge for the Slough 9 modelling site 7-5-9 Projections of gross surface area and WUA of chum salmon spawning habitat as a function of site flow and mainstem discharge for the Slough 21 modelling site 7-5-10 Projections of gross surface area and WUA of chum salmon spawning habitat as a function of site flow and mainstem discharge for the Upper Side Channel 11 modelling site ...........................•..............7-5-11 Projections of gross surface area and WUA of chum salmon spawning habitat as a function of site flow and mainstem discharge for the Side Channel 21 modelling site ..••......~........•.....•................7-5-12 xii ...,. ....' ....' LIST OF FIGURES (continued) Figure 7-5-6 .... 7-5-7 1 7-5-8~ 7-5-9 7-5-10 7-5-11 Time series plots of chum salmon spawning WUA as a function of mainstem discharge for the months of August through September,1981,1982,and 1983 for the Slough 8A modelling site •.•..•.......•..•....•...•.7-5-15 Time series plots of chum salmon spawning WUA as a function of mainstem discharge for the months of August through September,1981,1982,and 1983 for the Slough 9 modelling site ..•.....•.••............•...7-5-16 Time series plots of chum salmon spawning WUA as a function of mainstem discharge for the months of August through September,1981,1982,and 1983 for the Slough 21 modelling site ......•.....•....•.........7-5-17 Time series plots of chum salmon spawning WUA as a function of mainstem discharge for the months of August through September,1981,1982,and 1983 for the Upper Side Channel 11 modelling site ......•......•.7-5-18 Time series plots of chum salmon spawning WUA as a function of mainstem discharge for the months of August through September,1981,1982,and 1983 for the Side Channel 21 modelling site ..•..................7-5-19 Flow duration curves and mean monthly discharges for August and September based on the 30 year record of Susitna River discharge at Gold Creek.Sources: time duration curves -Bredthauer and Drage (1982); mean monthly discharges -USGS (1982),Lamke et ale (1983),and USGS (provi si ana 1 data)7-5-20 1 7-5-12 7-5-13 7-5-14 7-5-15 Projections of gross surface area and WUA of sockeye salmon spawning habitat as a function of site flow and mainstem discharge for the Slough 8A modelling site 7-5-21 Projections of gross surface area and WUA of sockeye salmon spawning habitat as a function of site flow and mainstem discharge for the Slough 9 modelling site 7-5-22 Projections of gross surface area and WUA of sockeye salmon spawning habitat as a function of site flow and mainstem discharge for the Slough 21 modelling site 7-5-23 Projections of gross surface area and WUA of sockeye salmon spawning habitat as a function of site flow and mainstem discharge for the Upper Side Channel 11. modell ;n9 site 7-5-24 xiii LIST OF FIGURES (continued) Figure ~r 7-5-16 7-5-17 7-5-18 7-5-19 7-5-20 7-5-21 7-5-22 7-5-23 7-5-24 7-5-25 Projections of gross surface area and WUA of sockeye salmon spawning habitat as a function of site flow and mainstem discharge for the Side Channel 21 modelling site o·•••••••••••••••••••••••••.o.~7-5-25 Time series plots of sockeye salmon spawning WUA as a function of mainstem discharge for the months of August through September,1981,1982,and 1983 for the Slough 8A modelling site 7-5-28 Time series plots of sockeye salmon spawning WUA as a function of mainstem discharge for the months of August through September,1981,1982,and 1983 for the Slough 9 modelling site ...............•...........7-5-29 Time series series plots of sockeye salmon spawning WUA as a function of mainstem discharge for the months of August through September,1981, 1982,and 1983 for the Slough 21 modelling site 7-5-30 Time series plots of sockeye salmon spawning WUA as a function of mainstem discharge for the months of August through September,1981,1982,and 1983 for the Upper Side Channel 11 modelling site 7-5-31 Time series plots of sockeye salmon spawning WUA as a function of mainstem discharge for the months of August through September,19B1,1982,and 1983 for the Side Channel 21 modelling site ..........•.........7-5-32 Projections of gross surface area and WUA of chum salmon spawning habitat as a function of site flow and mainstem discharge for the Side Channel 10 modell ;ng si te 7-5-33 Projections of gross surface area and WUA of chum salmon spawning habitat as a function of site flow and mainstem discharge for the Lower Side Channel 11 modell ing 5;te 7-5-34 Projections of gross surface area and WUA of sockeye salmon spawning habitat as a function of site flow and mainstem discharge for the Side Channel 10 model ling site 1 •••••0 •••••••••7-5-35 Projections of gross surface area and WUA of sockeye salmon spawning habitat as a function of site flow and mainstem discharge for the Lower Side Channel 11 model 1 ing site 7-5-36 xiv - - ""'" LIST OF FIGURES (continued) Figure 1 rr I I ;r I 7-5-26 7-5-27 7-5-28 7-5-29 7-5-30 7-5-31 Time series plots of chum salmon spawning WUA as a function of mainstem discharge for the months of August through September,1981,1982,and 1983 for the Side Channel 10 modell ing site .......•....•.......7-5-39 Time series plots of sockeye salmon spawning WUA as a function of mainstem discharge for the months of August through September,1981,1982,and 1983 for the Side Channel 10 modelling site ..............•.....7-5-40 Time series plots of sockeye salmon spawning WUA as a function of mainstem discharge for the months of August through September,1981,1982,and 1983 for the Lower Side Channel 11 modelling site •...........•.7-5-41 Time series plots of sockeye salmon spawning WUA as a function of mainstem discharge for the months of August through September,1981, 1982,and 1983 for the Lower Side Channel 11 modelling s~te 7-5-42 Comparisons of the ratio of upwelling area and chum salmon spawning WUA to gross surface area at modelled study sites projected at a mainstem discharge of 16,500 cfs for each of the modelled study sites (See Table 7-5-6 for k~y to spa~n~r utilization);r s = Spearman rank correlatlon coefflclent 7-5-43 Comparisons of the ratio of upwelling area and sockeye spawning WUA to gross surface area projected at a mainstem discharge of 16,500 cfs for each of the modelled study sites (See Table 7-5-6 for key to spawn~r.utilization);r s =Spearman rank correlation coeff1clent ...........•...............................7-5-44 xv LIST OF APPENDIX FIGURES Appendix Figure 1 .i 1 1 ""F I 7-A-l 7-A-2 7-A-3 7-A-4 7-A-5 7-A-6 7-A-7 Appendix 7-A Scatter plots of Slough SA low flow observed and predicted depths and velocities.The diagonal line in each plot represents the theoretical one-to-one relationship (i.e.observed=depth);the lines bounding the one-to-one line represent cufoff limits as defined in the methods section .....•...•........••....•......7-A-23 Scatter plots of Slough SA high flow observed and predicted depths and velocities.The diagonal line in each plot represents the theoretical one-to-one relationship (i.e.observed=depth);the lines bounding the one-to-one line represent cutoff limits as defined in the methods section .•.••......••..................7-A-24 Scatter plots of Slough 9 low observed and predicted depths and velocities.The diagonal line in each plot represents the theoretical one-to-one relationship (i.e.observed=depth);the lines bounding the one-to-one line represent cutoff limits as defined in the methods section .•..•..........................7-A-25 Scatter plots of Slough 21 low flow observed and predicted depths and velocities.The diagonal line in each plot represents the theoretical one-to-one relationship (i.e.observed=depth);the lines bounding the one-to-one line represent cutoff limits as defined in the methods section .•.....................•.......7-A-26 Scatter plots of Slough 21 high flow observed and predicted depths and velocites.The diagonal line in each plot represents the theoretical one-to-one relationship (i.e.observed=depth);the lines bounding the one-to-one line represent cutoff limits as defined in the methods section ...•....•...........•..........7-A-27 Scatter plots of Side Channel 10 observed and predicted depths and velocities.The diagonal line in each plot represents the theoretical one-to-one relationship (i.e.observed=depth);the lines bounding the one-to-one line represent cutoff limits as defined in the methods section .............•.....•...........7-A-2S Scatter plots of Upper Side Channel 11 observed and predicted depths and velocities.The diagonal line in each plot represents the theoretical one-to-one relationship (i.e.observed=depth);the lines bounding the one-to-one line represent cutoff limits as defined in the methods section .•.......••.........•..........7-A-29 xvi LIST OF APPENDIX FIGURES (continued) Appendix Figure 7-A-8 7-A-9 Scatter plots of Side Channel 21 low flow observed and predicted depths and velocities.The diagonal line in each plot represents the theoretical one-to-one relationship (i.e.observed=depth);the lines bounding the one-to-one line represent cutoff limits as defined in the methods section...............................7-A-3D Scatter plots of Side Channel 21 high flow observed and predicted depths and velocities.The diagonal line in each plot represents the theoretical one-to-one relationship (i.e.observed=depth);the lines bounding the one-to-one line represent cutoff limits as defined in the methods secti on 7-A-31 Appendix 7-E 7-E-1 Flow diagram of salmon spawning habitat analysis ..•...7-E-2 xvii q;m, ..... - ~, 1 ! LIST OF TABLES Table l' I -•I I I "i i 7-2-1 7-2-2 7-2-3 7-3-1 7-3-2 7-3-3 7-3-4 7-3-5 7-3-6 7-3-7 7-3-8 7-3-9 Section 2.0 Matrix of information from previous studies (ADF&G 1977,1978)used as criteria to initially select slough sites to be evaluated during 1981 for study using the IFIM PHABSIM modelling system ••..•.••••...•.7-2-3 Baseline biological,physical,and water quality characteristics of sloughs evaluated for study using the IFIM PHABSIM modelling system during 1981 (ADF&G 1981a,b)•••••••••••••e ••••~•••••••••••••••••••7-2-4 Comparison of biological and physical characteristics at major chum and sockeye salmon slough spawning habitats in the middle river reach .....7-2-5 Section 3.0 IFG-2 and IFG-4 mode"ing sites ....•...•...•..........7-3-2 Substrate classifications .................•...........7-3-5 Calibration data collected at Slough 8A study site ....7-3-12 Calibration data collected at Slough 9 study site ..•..7-3-21 Calibration data collected at Slough 21 study site ....7-3-32 Calibration data collected at Side Channel 10 study site ....011 •••••••••••••••••••••••••••••••••••••••••••••7-3-40 Calibration data collected at Upper Side Channel 11 study site 011 ••7-3-55 Calibration data collected at Side Channel 21 study s;te 7- 3-64 Summary of comparison of mainstem discharges at Gold Creek for which extrapolation ranges of IFG models apply streamflow at IFG model sites (cfs)7-3-75 xviii LIST OF TABLES (continued) Table Section 4.0 7-4-1 7-4-2 7-4-3 7-4-4 7-4-5 7-4-6 7-4-7 7-4-8 7-4-9 7-4-10 7-4-11 Substrate classification scheme utilized to evaluate substrate composition at spawning redds ............•.. Summary of histograms used to evaluate depth and velocity utilization data .....•.•..................... Grouping of substrate classification schemes used to evaluate preference •.•...•..•..•..•..•............•7-4-12 Number of measurements made at chum salmon redds in sloughs and side channels of the middle Susitna River;1982 and 1983 •.....•..•..•.......•.••....•.....7-4-15 Summary of statistics on various incremental groupings for chum salmon utilization depth histograms ~7-4-18 Summary of statistics on various incremental groupings for chum salmon utilization velocity histograms co ~..7 -4-24 Data used to develop joint (substrate and upwelling) suitability curve for chum salmon ••.••••..•.....•.....7-4-33 Number of measurements made at sockeye salmon redds in sloughs and side channels of the middle Susitna River in 1982 and 1983 •..............•....•...•.......7-4-36 Summary of statistics on various incremental groupings for sockeye salmon utilization depth hi stograms 7-4-39 Summary of statistics on various incremental groupings for sockeye salmon utilization velocity hi stograms 7 -4-43 Data used to develop joint (substrate and upwelling) suitability curve for sockeye salmon •..............•..7-4-51 xvix """ - ..... - LIST OF TABLES (continued) Table ...,. ;i ! Ij"I I I rr I, 7-5-1 7-5-2 7-5-3 7-5-4 7-5-5 7-5-6 Section 5.0 Runs of the habitat simulation model completed using other computational methods .....••.•...••...••••.•....7-5-3 Relationships of site flow to mainstem discharge used to derive plots of WUA of spawning as a function of mainstem discharge for each site when the site flow was directly controlled by mainstem discharge (Estes and Vincent-Lang 1980;Chapter I}..•..•....•....7-5-5 Typical base flows and associated WUAls (ft 2/1000 ft) for non-controlled flow conditions at study sites .....7-5-6 Range of WUA (ft 2/1000 ft)of chum salmon spawning habitat during non-controlling and controlling mainstem discharges and the percent of time the sites are not controlled and controlled by mainstem discharge during August and September .....•.....•........••............7-5-13 Range of WUA (ft 2/1000 ft)of sockeye salmon spawning habitat non-controlling and controlling mainstem discharged and the percent of time the sites are not controlled and controlled by mainstem discharge during August and September ......•...•......•.........••.....7-5-27 Comparisons of gross surface areas,upwelling areas, upwelling to gross surface area ratios,WUA,WUA to gross surface area ratios,and the relative chum/ sockeye salmon spawner utilization for modelled study sites at a mainstem discharge of 16,500 cfs 7-5-38 xx i' I, , LIST OF APPENDIX TABLES Appendix Table 1 1'"'1'., I I "i' .i 7-A-1 7-A-2 7-A-3 7-A-4 7-A-5 7-A-6 7-A-7 7-A-8 7-A-9 7-A-10 Appendix 7-A Comparison between observed and predicted water surface elevations,discharges,and velocity adjustment factors for 1983 Slough 8A low flow hy drau1i c rna del ~.. .. ...... .. .. .. ...... .. .. .. .. .. .. ...... .. .. .. .. .. .. .. .. .. .. ...... .. .. ......7-A- 2 Comparison between observed and predicted water surface elevations,discharges,and velocity adjustment factors for Slough 8A high flow hydrau 1i c mode 1 .... .......... .... .... ...... ...... ...... .......... .......... ...... .. .. ........7-A-3 Analysis of covariance table,testing for equivalent slopes between rating curve relationship developed from hydraul ic model versus,curve from R&M staff gage data,Slough BA 7-A-4 Analysis of covariance table testing for equivalent intercepts between rating curve relationship developed from hydraulic model versus curve from R&M staff gage data,Slough BA 7-A-5 Comparison between observed and predicted water surface elevations,discharges,and velocity for adjustment factors Slough 9 hydraulic model ..•....7-A-6 Analysis of covariance table,testing for equivalent slopes between rating curve relationships developed from hydraulic model versus curve from ADF&G staff gage data,Slough 9..•.......•........•••••...........7-A-7 Analysis of covariance table,testing for equivalent intercepts between rating curve relationships developed from hydraulic model versus curve from ADF&G staff gage data,Slough 9 ·..............•...................7-A-8 Comparison between observed and predicted water surface elevations,discharges,and velocity for adjustment factors Slough 21 low flow hydraulic mode 1 .;III 7-A-9 Comparison between observed and predicted water surface elevations discharges,and velocity for adjustment factors Slough 21 high flow hydraulic model ............•....•....................7-A-IO Analysis of covariance table,testing for equivalent slopes between rating curve relationship developed from hydraulic model versus curve from ADF&Gstaffgage data,Slough 21 ........•.·7-A-l1 xxi LIST OF APPENDIX TABLES (continued) Appendix Table 7-A-ll 7-A-12 7-A-13 7-A-14 7-A-15 7-A-16 7-A-17 7-A-18 7-A-19 7-A-20 Analysis of covariance table~testing for equivalent intercepts between rating curve relationship developed from hydraulic model versus curve from ADF&G staff gage data t Slough 21e •••~•••~••••.•••~.e •••••••••~.~.7-A-12 Comparison between observed and predicted water surface elevations,discharges,and velocity for adjustment factors 1983 Side Channel 10 hydraulic mode 1••••••••••••. •• ••••••• •••••••• ••••. •• •• ••••• •.••7-A-13 Analysis of covariance table,testing for equivalent slopes between rating curve relationship developed from hydraulic model versus curve from ADF&G staff gage data~Side Channel 10 7-A-14 Analysis of covariance table,testing for equivalent intercepts between rating curve relationship developed from hydraulic model versus curve from ADF&G staff gage data,Side Channel 10 .....•.....................7-A-15 Comparison between observed and predicted water surface elevations,discharges~and velocity for adjustment factors 1983 Upper Side Channel 11 hydraul ic model ...........•...........................7-A-16 Analysis of covariance table,testing for equivalent .slopes between rating curve relationship developed from hydraulic model versus curve from ADF&G staff gage data,Upper Side Channel 11 7-A-17 Analysis of covariance table,testing for equivalent intercepts between rating curve relationship developed from hydraulic model versus curve from ADF&G staff gage data,Upper Side Channel 11 7-A-18 Comparison between observed and predicted water surface elevations~discharges,and velocity for adjustment factors 1983 Side Channel 21 low flow hydraul ic model 7-A-19 Comparison between observed and predicted water surface elevations,discharges,and velocity for adjustment factors 1983 Side Channel 21 high flow hydraul ic model .................•.....................7-A-20 Analysis of covariance table~testing for equivalent slopes between rating curve relationship developed from hydraulic model versus curve from ADF&G staff gage data, Side Channel 21 7-A-22 xxii - ""'I' I I 7-B-1 7-B-2 7-C-l 7-C-2 7-C-3 7-C-4 7-C-5 7-C-6 7-0-5 Appendix 7-B Habitat data collected at chum salmon redds ........•..7-B-2 Habitat data collected at sockeye salmon redds .....•..7-B-13 Appendix 7-C Summary of variance statistics and tests for various groupings for chum salmon depth histograms .••.........7-C-2 Comparison of incremental mean and standard deviation values with non-incremental values for various grouping of chum salmon depth and velocity hi stogranls -110 7-C-3 Summary of various statistics and tests for various groupings for chum salmon velocity histograms 7-C-4 Bivariate correlation statistics for evaluating independence of habitat variables used in the development of suitability criteria curves for chum and sockeye salmon 7-C-5 Summary of various statistics and tests for various groupings for sockeye salmon depth histograms ..•....•.7-C-6 Comparison of incremental mean and standard deviation values with non-incremental values for varios groupings for sockeye salmon depth and velocity histograms 7-C-7 Summary of variance statistics and tests for various groupings for sockeye salmon velocity histograms 7-C-8 Appendix 7-0 Projections of gross surface area and WUA of chum and sockeye salmon spawning habitat at Slough 8A 7-0-2 Projections of gross surface area and WUA of chum and sockeye salmon spawning habitat at Slough 9.•.....7-0-3 Projections of gross surface area and WUA of chum and sockeye salmon spawning habitat at Slough 21 •••...7-0-4 Projections of gross surface area and WUA of chum and sockeye salmon spawning habitat at Upper Side Channel 11 II 7-D-5 Projections of gross surface area and WUA of chum and sockeye salmon spawning habitat at Side Channel . 21 7-0-6 xxiii Appendix 7-D (continued) 7-0-6 7-0-7 Projections of gross surface area and WUA of chum and sockeye salmon spawning habitat at Side Channel 10 C •iii •e eo _ •co fl •••••••••iii ••••iii CI ••e _•••IiiI 0 iii Q ••0 e _•••iii e ••III ••7 -0-8 Projections of gross surface area and WUA of chum and sockeye salmon spawning habitat at Lower Side Channel 11 .......•.....•...·••........•................7-0-9 xxiv - - - LIST OF PLATES Plate Section 2.0 7-2-1 7-2-2 I""" 7-2-3 7-2-4 7-2-5 7-2-6 7-2-7 Slough 8A modelling site,June 1,1982,mainstem discharge:23,000 cfs _~7-2-10 Slough 9 modelling site,June 1,1982,mainstem discharge:23,000 cfs 7-2-15 Slough 21 modelling site,June 1,1982,mainstem discharge:23,000 cfs •.••.....•.••.•..•••••••.•....•..7-3-19 Side Channel 10 modelling site,June 1,1982,mainstem discharge:23,000 cfs 7-3-23 Lower Side Channel 11 modelling site,August 16,1983, mainstem discharge:12,500 cfs 7-3-24 Upper Side Channel 11 modelling site,June 1,1982, mainstem discharge:23,000 cfs .....•..................7-3-26 Side Channel 21 modelling site,June 1,1982,mainstem discharge:23,000 cfs ....•.......••..................•7-3-29 xxv """ ! FOREWARD This chapter presents an evaluation of the suitability of selected side channel and side slough habitats located in the middle reach of the Susitna River f.or spawning by chum and sockeye salmon as a function of flow.It is divided into six sections as described below: Section 1.0:General Introduction -The rationale,objectives, and general study approach utilized in the evaluation are presented in this section. Section 2.0:Study Site Selection - A discussion of the concepts and rationale used in the selection of study sites is presented in this section along with general descriptions of selected study sites. *Section 3.0:Hydraulic Simulation Modelling -The development and use of hydraulic simulation models to forecast the range of water depths,velocities,substrates, and upwelling conditions available for chum and sockeye salmon spawning as a function of flow in side slough and side channel study sites are discussed in this section. Section 4.0:Fish Habitat Criteria Analysis This section discusses the behavioral responses of spawning chum and sockeye salmon to various levels of selected habitat variables (depth,velocity,substrate,and upwelling)and the corresponding development of weighted behavioral response curves (i .e., suitability criteria). Section 5.0:Spawning Habitat Area Projections -The process of linking site-specific hydraulic simulation data with suitability criteria (using a habitat simulation model)to calculate projections of Weighted Usable Area (WUA)of chum and sockeye salmon spawning habitat within study sites as a function of flow is presented in this section. Section 6.0:Summary_and Conclusions A summary of these investigations are presented in this section. *The hydraulic simulation models discussed in Section 3.0 were also developed to support modelling of juvenile salmon and resident fish utilization of these habitats.The juvenile salmon and resident fish habitat modelling is reported in Schmidt et al.(1984).A discussion of the cover component of the models,which is specific to that analysis,is not included in this report. 7-F-l .- - T 1.0 GENERAL INTRODUCTION 1.1 Background and Objectives This chapter presents the results of an investigation the ADF&G Su Hydro .Aquatic Studies Team has conducted since 1981 to evaluate the effects of flow on spawning habitat usability within selected side channel and side slough habi tats located in the Talkeetna to Devil Canyon reach of the Susitna River (middle river reacjl).Of the seven major habitat types identified for the Susitna River,side channels and side sloughs were chosen for study since hydraulic conditions within these habitat areas are likely to b~significantly altered by changes in the flow which will result from the filling and operation of the proposed hydroelectric facility.The persistence of spawning habitat within these habitat areas will largely depend on maintainence of passage conditions to and the availability of suitable water depths and velocities,and substrates within these areas under with-project flow conditi ons.(An eval uati on of passage conditions to and within these habitats is presented in Chapter 6 of this report).Chum and sockeye salmon were chosen for evaluation because they are the dominant species which presently spawn in side channel and side slough habitats of the Susitna River. The overall objective of this investigation has been to evaluate the suitability of selected side channel and side slough habitats in the middle reach for chum and sockeye salmon spawning as a function of flow.This objective was evaluated using the Instream Flow Incremental Methodology (IFIM)Physical Habitat Simulation (PHABSIM)modelling system developed by the US Fish and Wildlife Service Instream Flow Group (IFG)(IFG 1980;Bovee 1982).Within the overall objective of this investigation,three specific tasks were addressed: 1.To collect field data to forecast,through the use of hydraulic simulation models,the values of selected hydraulically controlled variables (i.e.,water depth and velocity)important for chum and sockeye salmon spawning as a function of local flow.Data on streambed composition and groundwater upwelling,which are considered important to spawning,yet assumed to be independent of local flow,were also forecasted. 2.To collect field data to determine the behavioral responses of spawning chum and sockeye salmon to variations in selected habitat variables (depth,velocity,substrate,and upwelling) to be used in the development of weighted behavioral response criteria for each habitat variable.The resulting suitability criteria,derived from habitat utilization and availability data,describe the relative probability that a spawning fish will utilize some ·increment of a habitat variable within a usable range of that habitat variable. *The seven major habitat types present in middle reach of the Susitna River are:mainstem channel,side channel,side slough,upland slough,tributary,tributary mouth,and lake (Figure 7-1-1). 7-1-1 WIEHAl IlABIIAT [AUGORIES or THE SUSIINA RIVER ~:~:~:a;I:~Jhora:JeUs\:u~tf~rss n~~~n~:~c:~::ct'el:u:rthha~h~taslurtc~h~~t~~~ of ttle ma1n!iotell susttnl Rivet or its side chaMeh-.lhese sloughs Ire characti!!ttled by the presence of beaver dams and an accuIM.lat10n of silt covering the substrate resu1thg froll the absence of minstelft scouring "WI. Tributary Habitat consists of the fun coanplellent of hydraulic and IIll)l"phologic cOl1dhtons that occ....In the trtbutarte5.Thetr senonal strea",flow.5edtment.and thef'1lll1 regtn:s l1lfleCl the fntegration of the hydrology,geology.and clllMte of the tributary drainage.The physical .ttrtbutes of tflbul.ry hilbttat arM hQt dependent on IIIiItnsteiU condiUon5. Trtbl,ltary Mouth Hallftat ell;tends froll tbe uppermost potnt 1n the trtbutary Influenced by Ntn5tem Susitna River 01"slough backwater effects to the do"mstrea.extent of the tributary p'ume whh:h edends tnto the •...,tnstell Susltn.River or slough (ADF&G 19B1c.1982b). Lake HabUn conshts of varlouili hmttc envtronlllf'nts that occur within the SusitN.River dra.in'lje.These habtl't5 range frOIll small,shallow. Isolated htes perched on the tundra to larger.deeper lakes which connect t"the IIIilItnstem SUitt"'a River through wen defined trlbuury systems.Tlle lakes receive their water frDR!springs.'urface runoff and/or tributaries. 1)Mainste.Habitat (onststs of those porUol'Is 01 the StJ"Una River thill nOr1lilly cOnvey streamflow throughout th,year.80th single and b.I1Upie channel f"elches.Ire tncluded tn thtl habHlt category.Grooru:lNater and trtbutary inflow appear to be tnconsequential COl'ltribdtors to the overall ~haractedst1cs of 1M1nste.habUat.NitRstel'habUat is lyptcllly characterized by high water velocities Ind wel1 armored stread)eds. 'Substrates generally (pnstst of boulder and cobble she IIaturtals wi th tnterst1tbl spaees ft1\ed with •gfwt~\tte "'bture of "Wtl grl.veh and gladal sands.Suspended sediment concentrattons and turbtdity are hfgh dur1ng su.er due to 'he tnflu,"ce ot ghcf'l lrelt~water.S,reilllnflows recede fn early flll and th,mtnstellll ,lean appreciably tn October.An tce cover tonns (In the ther fn I,te Novedu~r or [Jecenber. 2)Side Channel ffabttat consfsts of tho&e portions of the Susftna River that n(lrNlIy convey strealllflow during 'he open water season but become :r:~1:~l~t:::t~~e:e1.r::'t=~t:~:t'i:~o;'ha~~c:i~.~~d~n(~::~~~::~:~:~ wo'er coone'l HOMing through partial I)'submerged grne'bars elnd islands along the lIIugtn,of thlfo INtnsh_river.Stde channel streambed ele~ vat tons ife typ1cally lower than the mean mnthl)'NateI'surface ele~ vaUonS of the Ninstelll SUlftna Rher ob5erved durtng J"ne~July and August.Side channlfo'habttats are charactertzed by stJ.lI"",er depth" lower ",.loc1t1es and SoNHef"struwlled Mter1als tftilon the adjac.ent habUat of the lMinSitelP river. Sfde SloUgh Habllat h located in spring fed overflow channels beble..n the edge of the floodplain .lId the ..tnite.and st~channels of the SuS1tRa Rtver and ts usuany separated frOll the lM.nstelft 'nd side channeh II}'well vegetated bars.An up0!ied alluvial bem often separ.tes the head of the slough frDlll roofnsten:l or sfde channel flowt. The controll1nll streaiOOed/streambank elevations at the upstrealll end of ~t:~::~:~:~:;f:':l~lh::::::,:~nS~::t::t:r,::r!:~:r:~:v;~:03~n:~ July,.nd August.At tntennedtate ilnd 10000-f10"l'pertodS.the side sloughs convey clear w.ter frOll SNl1 trtbutartes ~nd/or upwelling groundNiler (ADf&G 19R1e.19SZb).These clear water tnflows are essential con- trtblltl)rs to the e){htence of this habUat type.The water surface elevation (If the Susttna River -generally causes •bacbater to ed..nd well up-tnto the slough ftlMll fts lwer end (ADF&G 19B1c~1982b).hen though th1s subUantial backwater e~dsts.the sloughs functton hydnu- HuH,very hu;h like small stream 'S)'stems imd severa'hundred feet of the slough channel often tonveys water tndepel1dent of lIillnstem backwater effects.At high flows the ...ater surfau elevatton of thl!rnainstem river is stlffidf!l1t to overtop the upper end of the slough (ADf&G 1981c • 1902b).Surface liIater temperatures 11'1 the sMe sloughs durfng SUllIllIl!r Ill(mths Ire princtpall)'I function of .tr temperature.solar radfat10R. 'nd the temperature of the lou 1 "moff. J) 6) 7) 5) 4) .........::::........".'.~:. ~<:}:::.:::\.,::.;;.;....');" "'"-.J I....... I N Fi gure 7-1-1.General habitat categories of the middle Susitna River - a conceptual diagram (ADF&G 1983). ,l I J I I J J J »t ,1 ~J I .1 .j i I 3.To calculate,using a habitat simulation model linking the data gathered in conjunction with objectives 1 and 2 above, the weighted usable area (WUA)of chum and sockeye salmon spawning habitat as function of flow for the modelled study sites. 1.2 Study Approach The quantity and quality of chum and sockeye salmon spawning habitat in side sloughs and side channels is dependent on a multitude of interrelated habitat variables,including water depth and velocity, which are intimately related to both mainstem discharge and local flow, and streambed composition and upwelling which are less directly affected by mainstem discharge and local flow.Significant temporal and spatial differences in these habitat variables are expected to affect habitat suitability for spawning by salmon in sloughs and side channels. The response of habitat variables to naturally occurring changes in flow could not be cost-effectively evaluated by monitoring a natural system of this magnitude on a continual basis.For this reason,the IFIM PHABSIM modelling system of the U.S.Fish and Wildlife Service IFG (IFG 1980;Bovee 1982)was selected in 1982 (ADF&G 1983a,b:Appendix D)as a means of quantifying the probable effects of flow patterns on existing spawning habitat in side slough and side channel habitats. The IFIM PHABSIM system is a collection of computer programs used to simulate ·both the available hydraulic conditions and usable habitat at a study site for a particular species/life phase as a function of flow. The IFIM PHABISM modelling system is based on the theory that changes in riverine habitat conditions can be estimated from a sufficient hydraulic and biologic field data base.The modelling system is based on a three step approach.The first step uses field data to calibrate hydraulic simulation models to forecast anticipated changes in physical habitat variables important for the species/life phase under study as a function of flow.The second step involves the collection and analysis of biological data to determine the behavioral responses of a particular species/life phase to selected physical habitat variables important for the species/life phase under study.This information is used to develop weighted behavioral response criteria curves (e.g.,utilization curves, preference curves,or sui tabi 1 ity curves).The thi rd step combi nes information gained in the first two steps to calculate weighted usable area (WUA)indices of habitat usability as a function of flow for the species/life phase under study. The IFIM PHABSIM modelling system is intended for use in those situations where the flow regime and channel structure are the major factors influencing riverine habitat conditions.Furthermore,the physical and biological aspects of field conditions must be compatible with the underlying theories and assumptions of the models being applied.Specific assumptions required in the application of these models and the resulting limitations of the projected data are discussed in the Sections 3.0,4.0,and 5.0,respectively. 7-1-3 1.3 Previous Studies Background studies to assist in selection of study sites for evaluation using the IFIM PHABSIM"modelling system were initiated in 19B1.Based on these studies,three side slough habitats (Sloughs BA,9,and 21)in the Talkeetna to Devil Canyon reach were selected for evaluation (AOF&G 1982). Spawning habitat assessment using the IFIM PHABSIM modelling system was initiated in Sloughs BA,9,and 21 in 1982 (ADF&G 1983b:Appendix D). Lower than average discharge conditions in 1982,however,prohibited the collection of sufficient hydraulic data necessary for calibration of the hydraulic simulation models for these study sites.These conditions also restricted passage into sloughs by spawning salmon,which limited the collection of fish habitat utilization data used to develop weighted behavioral response criteria curves. In 1983,the additional field data necessary for complet"ing the IFIM PHABSIM modelling analysis were collected at each of the three slough study sites.In addition,data necessary for completing an IFIM PHABSIM analysis at four side channel study sites (Side Channels 10,Lower and Upper 11,and 21)were collected.These results are presented in this chapter. 7-1-4 - - - 1 I 1 IT , I ,.. I T 2.0 STUDY SITE SELECTION This section presents the concepts and rationale used in the selection of study sites evaluated using the IFIM PHABSIM modell ing system.In addition,general descriptions of sites selected for evaluation are presented. 2.1 Study Site Selection Concepts Two basic approaches are commonly used for selecting study sites to be evaluated using the IFIM PHABSIM modelling system:the critical and representative concepts (Bovee and Milhous 1978;Trihey 1979;Bovee. 1982).Application of the critical concept requires knowledge of a stream's hydrology,water chemistry,and channel geometry in addition to rather extensive knowledge of fish distribution,relative abundance,and species-specific life history requirements.Criteria for application of the representative concept are less restrictive,enabling this concept to be used when only limited biological information is available or when critical habitat conditions cannot be identified with any degree of certainty.In this study,an adaptation of these concepts were used to select study sites. In the critical concept,a study area is selected because one or more of the physi ca 1 or chemical attri butes of the habitat are known to be of critical importance to the fish resource.That is,recognizable physical or chemical characteristics of the watershed hydrology, instream hydraulics,or water quality are known to control species distribution or relative abundance within the study area.Because of this,an evaluation of critical areas will provide a meaningful index of species response in the overall critical study area. The representative concept acknowledges the importance of physical habitat variables throughout the entire study stream for sustaining fish populations.Thus,under the representative concept approach,study areas are selected for the purpose of quantifying relationships between streamflow and physi ca 1 habitat conditi ons important for speci es/l ife phase under study at selected key locations (representative reaches) that collectively exemplify the general habitat characteristics of the entire river segment inhabited by the species/life phase under study. 2.2 Study Site Selection 2.2.1 Slough Study Sites Preliminary studies of the Susitna River (ADF&G 1974,1976,1977,1978) indicated that slough habitats in the middle reach of the Susitna River are utilized for spawning and rearing by chum and sockeye salmon. Because this type of habitat is located along the lateral margins of the river flood plain,these habitats will be subject to dewatering during the open water field season if naturally occurrlng summer discharges are significantly reduced by the proposed hydroelectric project.For these reasons,slough habitats in the middle river segment were initially selected in 1981 as critical habitats for study using the IFIM PHABSIM modelling system (ADF&G 1981a,b,1982).It was not possible,however, 7-2-1 to cost-effectively evaluate all slough habitats in the middle river reach.For this reason,baseline studies were conducted during 1981 to assist in selection of specific slough habitats to be evaluated using the IFIM PHABSIM modelling system. Based on a review of baseline fishery,water quality,and channel morphology data from previous ADF&G investigations (ADF&G 1974, 1976, 1977,1978);discussions with personnel from Acres American,Inc., E.Woody Trihey and Associates,and R&M Consultants Inc.familiar with the middle river slough habitat conditions;and,results of a reconnaissance trip to slo~gh habitats in the middle river reach in June 1981 by AOF&G Su Hydro and U.S.Geological Survey (USGS)personnel,six slough habitats known to support chum and sockeye salmon spawning were selected for further baseline evaluation to assist in the selection of specific sites for study using the IFIM PHABSIM modelling system.These six sloughs (Sloughs 8A,9,11,16B,19,and 21)were thought to represent a cross section of the biological,physical,and water quality characteristics typical of slough habitats in the middle reach of the Susitna River (Table 7-2-1). On the basis of additional field "investigations conducted during the fall of 1981 (ADF&G 1982),Sloughs 8A,9,and 21 were selected for evaluation using the IFIM PHABSIM modelling system.These sloughs were selected based primarily on their relatively high utilization by spawning chum and sockeye salmon and their amenability to habitat modelling using the IFIM PHABSIM modelling system (Table 7-2-2). Although Slough 11 is also heavily utilized by spawners,the relatively low frequency of overtopping at this slough would have made it difficult to evaluate using the IFIM PHABSIM modelling system.Additionally,it was felt that it was unlikely that spawning habitat usability in this slough would be significantly affected by further reductions in mainstem discharge due to its relatively low frequency of overtopping.Given the stability of the hydraulics in this slough,it was deemed not appropriate to apply the IFIM PHABSIM modelling system to this slough. Sloughs 16B and 19 were not selected for evaluation because of their comparatively low util ization by spawning chum and sockeye salmon.It .was also felt that backwater effects at Slough 19 would significantly complicate the hydraulic simulation modelling process at this slough. To establish the representativeness of Slough 8A,9,and 21 to other non-modelled sloughs in the middle river reach,available baseline data on the biological and physical characteristics of the modelled sloughs were compared with similar information available for selected non-modelled slough habitats in the middle reach which are known to support chum and sockeye salmon spawning (Table 7-2-3).From a consideration of the information presented in Table 7-2-3 it appears that Sloughs 8A,9,and 21 are generally representative of the physical and biological conditions present within other selected non-modelled slough habitats which support chum and sockeye salmon spawning in sloughs of the middle river reach.Collectively,the modelled and non-modelled sloughs listed in Table 7-2-3 support 81%of the documented ,.. - *For further discussion of this site selection process refer to ADF&G (1981a,1982,1983a). 7-2-2 Table 7-2-1.Matrix of information from previous studies (ADF&G 1977,1978)used as criteria to initially select slough sites to be evaluated d~ring 1981 for study using the IFIM PHABSIM modelling system. Key:P =Presento=Absent +=Less than 10 fish ++=10-100 fish +++=More than 100 fish =Data not available Table 7-2-2.Baseline biological,physical,and water quality characteristics of sloughs evaluated for study using the IFIM PHABSIM modelling system during 1981 (ADF&G 1981a,b). PHYSICAL HABITAT BIOLOGICAL DATA DATA WATER QUALITY DATA Dissolved Specific River Spawning Rearin~Streambed Oxygen Conductance Turbidity Slough Mile Chum Sockeye Chum Soc eye Morphology (mg/l)E1:!(umho/cm)(NTU) 8A 125.3 +++++0 0 Beaver Dam 8.8-10.5 6.8-7.6 108-160 1-205 Backwater 9 128.3 ++++0 +Open Channel 10.6-11.4 6.8-7.4 113-145 1-130 ....... I Open ChannelN11135.7 +++++++++0 9.3-10.7 6.8-7.1 144-222 2-98I .j::>o 168 137.8 + +-.-Open Channel 10.8-11.7 6.4-7.1 64-72 1-43 19 140.0 + +--Backwater 9.4-10.4 6.5-7.3 127-150 1-3 21 141.8 ++++- - Open Channel 10.3-11.3 7.0-7.7 103-226 1-150 Key:+++high utilization ++moderate utilization +low utilizationoabsent -unknown,data not available J 1 )l I J J J ,,.J J J t J ---]~ Table 7-2-3.Comparison of biological and physical characteristics at major chum and sockeye salmon slough spawning habitats in the middle river reach. HABITAT BIOLOGICAL PHYSICAL Percent Distribution in Sloughs River above RM 99 Channel Breaching Controlling Gradient Turbi dity Slough Mile Chum Sockeye Morphology Mainstem Q Mainstem Q (ft/mile)Substrate Upwell ing (NTU)-- 8 113.6 4.6 0.0 OC 24,000 24,000 Unknown SI/SD,RU/CO Present Unknown -....J 8A 125.3 15.1 13.0 BW,OC 33,000 33,000 12.5 GR/RU,SI/SD Present 1-205I N I tTl 9 128.3 11.1 0.7 OC 16,000 19,000 13.8 GR/RU,SI/SD Present 15-130 **9A 133.2 6.2 0.1 OC 19,600 19,600 16.1 RU/CO Present Unknown 11 135.3 16.9 66.3 OC 42,000 42,000 19.8 CO/RU Present 2-98 20 140.1 1.7 0.1 OC 22,000 27,000 13.5 RU/GR Present 4-50 21 141.8 20.2 12.0 OC 18,000 24,000 22.9 CO/RU,SI/SD Present 2-180 22 144.2 5.2 0.0 OC 20,000 23,000 15.2 CO/RU,SI/SD Present 8-84 ---- Totals 81.0 92.2 References A A B C C B B D D -*Estimated Key:DC -Open Channel References:A Barrett,et al.1984 BW -Backwater B Estes and Vincent-Lang 1984 -Chapter 2 CO -Cobble C Estes and Vincent-Lang 1984 -Chapter 3 RU -Rubble D ADF&C 1983a SI -Silt SD -Sand chum salmon and 92%of the documented sockeye salmon spawning in sloughs in the middle reach of the Susitna River. It may not be appropriate,however,to extrapolate the results of the modelled sloughs to non-modelled slough habitats.A prerequisite to such extrapolation is that the flow-related variables which are evaluated in the modelled sloughs are the habitat variables that limit or control the chum and sockeye salmon spawning that occurs in the non-modelled sloughs.If it is determined that some other habitat variables limit the spawning that occur in the nan-modelled sloughs (e.g.,water quality or temperature),then extrapolations of the modelling results are not warranted,regardless of the availability of suitable depth,velocity,substrate,and upwelling conditions.It is a1so recommended that the resul ts of the mode 11 ed sloughs do not be extrapolated to non-modelled sloughs which do not currently support chum and sockeye salmon spawning. 2.2.2 Side Channel Study Sites Prior to the onset of the 1983 field season it was decided that side channel habitats should also be evaluated using the IFIM PHABSIM modelling system since the physical characteristics of this type of habitat may also change considerably if naturally occurring summer discharges are reduced as a result of the proposed hydroelectric project.Although 1imited spawni ng currently occurs in these habitat areas under pre-project conditions,their utilization may increase if with-project discharges reduce usable habitat in sloughs and provide more favorable spawning habitat conditions in side channels. Additionally,these areas provide significant chinook salmon rearing habitat. In contrast to slough habitat areas,only a limited amount of baseline biological,physical,and water quality data was available for selecting representative side channel habitats in the middle reach of the Susitna River to be evaluated using the IFIM PHABSIM modelling system.Based on preliminary field observations and consensus among personnel from ADF&G Su Hydro and E.Woody Trihey and Associates familiar with middle river habitats,four side channel sites (Side Channel 10,Lower and Upper Side Channel 11,and Side Channel 21)were selected for study using the IFIM PHABSIM modelling system.These side channels were assumed to be capable of supporting either spawning or rearing salmon under appropriate flow conditions. Upper Side Channel 11 and Side Channel 21 were selected for evaluation because they are known to support limited chum/sockeye spawning. Additionally,these two side channels provide significant chinook salmon rearing habitat.Lower Side Channel 11 and Side Channel 10 were selected primarily because they provide significant rearing habitat for chinook salmon juveniles.A further reason for selecting Side Channel 21 and Lower Side Channel 11 was due to their proximity to Sloughs 21 and 11,areas which currently are utilized by spawning chum and sockeye salmon.It was thought that if with-project conditions cause passage problems into these sloughs,increased spawning may take place in their adjacent side channels if suitable spawning and incubation habitat became present. 7-2-6 - - '""" - ,~ ~I - I~ - ~, - ~- -, i""" I 1 I I Since baseline data on side channel habitats in the middle reach of the Susitna River are limited,the representativeness of the modelled side channels cannot be well documented.Chum and sockeye salmon have been observed to spawn at only two (Upper Side Channel 11 and Side Channel 21)of the four side channel sites evaluated.For this reason, projections of usable area of spawning habitat at these two sites can be used as an "index of usable spawning habitat as a function of flow at these sites.As chum or sockeye salmon spawning has not been observed in Side Channel 10 or Lower Channel 11,the projections of usable areas of spawn"ing habitat at these two sites were made solely for comparative purposes to verify model accuracy.Unless chum/sockeye salmon spawning is documented at these two sites,it is not recommended that the modelling results for these sites be used as an index of usable habitat at these sites.Furthermore,it is not recommended to extrapolate the results of the side channel modelling studies to non-modelled side channels unless utilization of such sites is verified by field observations and it is determined that the flow related habitat variables which are modelled are the habitat variables that limit or control the spawning in the non-modelled sites. 2.3 Study Site Descriptions A description of the general physical characteristics and utilization by spawning chum and sockeye salmon of each of the slough and side channel sites selected for evaluation using the IFIM PHABSIM modelling system is presented below by site.Information perta.i ning to juvenil e fi sh utilization within the study sites is presented in Schmidt et al. (1984). Side Slough 8A Side Slough 8A is located on the east bank of the Susitna River at river mile 125.3 (Figure 7-2-1).It is approximately two miles in length and is separated from the mainstem by two relatively large vegetated islands (Plate 7-2-1).The channel is relatively straight with a gentle bend near the head of the slough.Approximately 2,000 ft upstream of the mouth,a series of beaver dams are located across the braided channel which,depending on flow conditions,may block upstream migration of salmon.Approximately 2,500 ft upstream of the mouth,the channel divides into two forks,a northwest (NW)fork and northeast (NE)fork. The study site is located in the NE fork. An area of backwater occurs.at the mouth of this side slough during periods of moderate and high mainstem discharge which,depending on discharge,extends up to 1,000 ft into the slough.Above the backwater area is a 100-300 ft long riffle followed by a beaver dam.A large pool occurs behind the beaver dam into which the NW fork discharges.Another dam 1,200 ft further upstream impounds the discharge from the NE fork. The overall gradi ent of the slough is 10.5 ft/mi as compared to the overall gradient of the adjacent mainstem of 9.3 ft/mi.Substrate composition in the slough varies depending on location.Cobble/boulder substrates predominate in the upper half of the slough while 7-2-7 .....,,,..1- [J]MODELLED STUDY SITES o I mile (0 pprOIl.leal.) •RIVER M 1I.E Figure 7-2-1.Middle river study sites evaluated using the IFIM PHABSIM modelling system. 7-2-8 - -, - Slough 168--,,,,,,,, "..,,,..f 19 15292000 Lower Side Channel II EJ MODELLED STUDY SITES o mi Ie (approl.Ie a I') •RIVER MILE Figure 7-2-1 (continued). 7-2-9 '-J I N I t-'o ~~~ro.~7t~t~ti~l\., 6 STAFF GAGE --CROSS SECTION Plate 7-2-1.Slough 8A modelling site,June 1,1982,mainstem discharge:23,000 cfs. gravel/rubble substrates are characteristic of the lower half of the slough.Deposits of silt/sand are found in the backwater area at the slough mouth and in the pools formed by the beaver dams. Prior to overtopping by the mainstem,a base flow ranging from 1-20 cfs in the NE slough fork is maintained by surface runoff,groundwater seepage,and upwell i ng.Subsequent to overtoppi og,flows up to 70 cfs which are controlled by mainstem discharge have been observed in the NE fork.The lowest observed initial breaching discharge (see glossary) and controlling discharge of the NE channel are estimated to be 33,000 cfs*.Based on the 30 year historical flow record,however,this level of discharge only rarely occurs during the months of August and September,the primary months of chum and sockeye salmon spawni ng in sloughs (Figure 7-2-2). Chum and sockeye salmon and to a lesser extent pink and coho salmon utilize this side slough for spawning.Observed spawning areas of chum and sockeye salmon in this side slough are presented in Figures 7-2-3 and 7-2-4. Side Slough 9 Side Slough 9 is located on the east bank of the Susitna River at river mile 128.3 (Figure 7-2-1).It is approximately 1.2 miles in length and is separated from the mainstem by a large vegetated island (Plate 7-2-2).The channel is S-shaped and is composed of an alternating series of pools and riffles.Two small unnammed tributaries and Slough 9B empty into the slough.The banks generally have a moderate to steep slope and are 3 to 4 ft high. The overall gradient of the slough is 13.7 ft/mi as compared to the overall gradient of the adjacent mainstem of 8.7 ft/mi.Generally,the lower half of the slough has a relatively shallower gradient than the upper half. Substrate composition in the slough varies depending on location. Cobble/boulder substrates predominate in the upper half of the slough while gravel/rubble substrates predominate in the lower half.Deposits of silt and sand are found in the backwater and pool areas. An area of backwater occurs at the mouth of thi s side slough duri ng periods of moderate and high mainstem discharges.During periods of moderate mainstem discharges,the backwater area extends approximately 500 ft upstream to the base of the first riffle.During periods of high mainstem discharge,backwater inundates these first riffles and the lower half of the slough becomes one long backwater pool. Prior to overtopping by the mainstem,a base flow ranging from 1-5 cfs in the slough is maintained by two small tributaries,Slough 9B, groundwater seepage,and upwelling.During these periods,the upper *All mainstem di scharges cited in thi s chapter are referenced to the USGS Gold Creek gaging station #15292000. 7-2-11 SEPTEMBER 0----<>1981 •.1982 0---01983 • •HISTORICAL 30 YEAR RECORD == Q)Q)c:c:c:N c:Q00..c ..cUQ)U Gi <Il c:<Il CCl~c:<{""0 ""O)~N CDen..c enU ..cU ..c ..c......0-Ol 0-<Il <Il <Il :::J<Il :::J :::J~::!a.0""0 00a.ii5en en ii5...J (J):::) --=--~---o....... "'q -\'Q ... \......... \...............\...... \...... "0 ----\- AUGUST \ 0----<>1981 \ •.1982 \ 0---01983 \••HISTORICAL \30 YEAR RECORD \ 5 10 15 20 25 30 35 40 60 60 80 20 20 40 40 ~o .J l1. W I- CJ) CJ) ~ C -....;OI-+---....,..---.,---r----..,.---,;;,-oIQ..r----:::r:-"'""'-::'::"'--""':'"o 5 10 15 20 25 30 35 40 SUSITNA RIVER DISCHARGE AT GOLD CREEK (x 10 3 cfs) 100 80 w ~a::« :I: U CJ) Ci :i:w I- CJ) Z ~ :i: >-CD C W .J .Joa:: I- Z 100ou >-.J I- U Wa:: Ci CJ) Figure 7-2-2.Flow duration curves for the months of August and September for the years 1981,1982,and 1983 and the 30 year historical discharge composite record depicting discharge for the modelled study site. 7-2-12 -....J I N I f-' W SLOUGH SA Chum Spawning Area f]1983 IB 1982 D 1981 o 500 I I FEET (.lIppro>.Scol,' ~SUs;r"'4 I RIVER }I Figure 7-2-3.Chum salmon spawning areas,Slough 8A,1981, 1982,1983. IY";"..:11."::'I~" NIVER '-iIr.:.:...i'I·;·:'··\·'·:·~'">"(':,;\i":;\";"".~ 126 Gl -----S {/SIr~-4~ SLOUGH 8A Sockeye Spawning Area ~1983 E:J 1982 CI 1981 o ~oo '-J I N I I-' ~ I ! fEET (Appro I,Seol,1 Figure 7-2-4.Sockeye salmon spawninq areas Slough 8A,1981,1982,1983. '-J I N I..... U1 6 STAFF OAOE --CROSS SECTION Plate 7-2-2.Slough 9 modelling site,June 1,1982,mainstem discharge:23,000 cfs and sockeye salmon utilize this Observed spawning areas of chum are presented in Figures 7-2-5 half of the slough is dry with flow occurring intragravelly.Subsequent to overtoppi ng,slough flows rangi ng up to 500 cfs have been observed which are controlled by mainstem discharge.The initial breaching and controlling discharges of this side slough are 16,000 and 19,000 cfs, respectively.Based on the 30 year historical flow record,this level of discharge is typically exceeded more than 65%of the time in August but only 30%of the time in September,the months of peak spawning activity in sloughs (Figure 7-2-2). Chum salmon and to a lesser extent pink side slough for spawning (Table 7-2-3). and sockeye salmon in this side slough and 7-2-6. Side Slough 21 Side Slough 21 is located on the east bank of the Susitna River at river mile 141.8 (Figure 7-2-1).It is approximately 0.5 miles in length and is separated from the mainstem by a large vegetated island (Plate 7-2-3).Approximately halfway up the slough,the channel divides into two forks,a NW and NE fork.The banks are generally steep and undercut and are approximately 5 ft high.Immediately downstream of the mouth of the slough proper is an area that exhibits slough-like characteristics during unbreached conditions and becomes essentially an extension of the slough during these periods.During 1982,which was a low-flow year, this area was slough-like during the majority of the spawning period and the majority of the spawning occurred here rather than in the slough due to access problems at the mouth resulting from the low flow.The study site was therefore established in this area. The overall gradient of the slough is 22.9 ft/mi as compared to the overall gradient of the adjacent mainstem of 12.2 ft/mi.Generally,the channel cross-section is flat with a relatively deep,narrow channel running along the east bank. The predominant substrate in the slough is cobble/boulder.However, silt/sand deposits are found in backwater and pool areas.Only a small area of backwater occurs at the mouth of this side slough during periods of high mainstem discharge. Pri or to overtoppi ng by the rna i nstem,a base f1 ow up to 5 cfs in the side slough is maintained by a small unnammed tributary,local runoff, groundwater seepage,and upwell i ng.Duri ng these peri ods,the upper half of the slough is dewatered with isolated pools.Subsequent to overtopping,the flow in the slough has been observed up to 350 cfs and is controlled by mainstem discharge.The lowest observed initial breaching discharge that influences the study site at this side slough is 18,000 cfs,which compares to a controlling discharge of 24,000 cfs. Based on the 30 year historical flow record,however,this controlling discharge is only exceeded less than 30%of the time in either August or September,the months of peak spawning activity in sloughs (Figure 7-2-2). 7-2-16 1 I I rl 1983 []1982 a 500 •FEET I (Appro ••Scale) SLOUGH 9 Chum Spawning Areas Tributary B ffi 129--RIVf.R "'.::':'."\' ....:"~A":~rN 5 I """.•,U '.i.,.:f.':.-::....~.~...:';~.:.!.-t...•~.,:..... .::::.c.~.~;:."..J..:-}.•".!.f.l ~.~'.~;;.,:..~::.";~j:-.'". :l Tributary A " "-J I N I...... "-J Figure 7-2-5.Chum salmon spawning areas,Slough 9,1982 and 1983. .:d:!~:,:'··:~~'!"?"";"t:'l (~""":"""";~.",.•.~1 ..~'(''';''l·~~:I(·:·:·,J·C\·,.I·{~ :':'.y.:..~:::'....-;:~~;.'~t.'? rJ 1983 rg 1982 ,,,;.'''··:;f:~:'':...'''';'':.=....'1'·'-....·:-··r Slough 9E/~ SLOUGH 9 Sockeye Spawning Areas Tributa.ry B --(B129RIV£R....,'.~.~.~US,r NA ~~ '-J I N I...... OJ Figure 7-2-6.Sockeye salmon spawning areas,Slough 9,1982 and 1983. "-J I N I....... ~ (::)STAFF GAGE; -CROSS SECTION· Plate 7-2-3.Slough 21 modelling site,June 1,1982,mainstem discharge:23,000 cfs. as compared an Generally,the narrow channel Chum salmon and to a lesser extent sockeye and pink salmon utilize this side slough for spawning.Observed areas of spawning of chum and sockeye salmon in this side slough are presented in Figures 7-2-7 and 7-2-8. Side Channel 10 Side Channel 10 is located on the west bank of the Susitna River at river mile 133.8 (Figure 7-2-1).It is approximately 0.4 miles in length and is separated from the mainstem by a large gravel bar (Plate 7-2-4).It joins with Slough 10 forty feet upstream of the mouth of the slough.The east bank along the gravel bar is gently sloping as compared to the west bank which is high,steep,and undercut.A pool/riffle sequence predominates throughout the side channel along with a backwater pool at the mouth.Ouri ng peri ods of moderate to hi gh mainstem discharge,the backwater area extends up to 1,000 ft upstream of the side channel mouth. The overall gradi ent of the side channel is 20.5 ftlmi overall gradient of the adjacent mainstem of 8.9 ft/mi. channel cross section is relatively flat with a deep running along the west bank. Substrate composition in the slough varies depending on location.The upper half of the slough is generally characterized by cobble/boulder substrates while the lower half is characterized by gravel/rubble substrates.Silt/sand deposits are found in pool areas and the backwater zone near the mouth. Prior to overtopping by the mainstem,a base flow up to 10 cfs in the side channel is provided by local runoff and groundwater seepage. Subsequent to overtopping,flows up to 260 cfs in side channel have been observed.Under these conditions,the flow becomes turbid and controlled by the mainstem.The initial breaching and controlling discharges for this side channel are the same being 19,000 cfs.Based on the 30 year historical flow record,this controlling discharge is typically exceeded more than 65%of the time in August but only 30%of the time in September,the months of peak spawning activity in side channels (Figure 7-2-2). No salmon species have been observed to utilize this side channel for spawni ng.For thi s reason,projecti ons of usable area of spawni ng habitat at this site were only made for comparative purposes to verify model accuracy. Lower Side Channel 11 Lower Side Channel 11 is located on the east bank of the Susitna River at river mile 134.6 (Figure 7-2-1).It is approximately 0.7 miles in length and is separated from the mainstem by a large w'ell-vegetated island (Plate 7-2-5).Just upstream of the confluence of Slough 11 the channel divides into two forks,a NE and NW fork.Substrate in the side channel predominantly consists of cobble and rubble interspersed with large gravel and sand.Only a small backwater area has been observed at the mouth of this side channel. 7-2-20 :.:.;:;:......\.•.:~--:.. .'.-&.:•'."':~'::•••.~•• • • ' °0 ~: 61142 ---- 2/. RiVER .~-:.;\." :..•..:<':.:':':;':":;::'~'. ::;:':"7.:.-.:...~:-."":..1:-(,~'l~f:J;.;!~~i·.r.L-~.:: sus/rNA..----- SLOUGH 21 Chum Spawning Areas ~1983 CJ 1982 EJ 1981 o 500 I ! FEET (Appro •.Scole ) -...J I N I N >-' -.:," Figure 7-2-7.Chum salmon spawning areas,Slough 21,1981,1982,1983. EBI42 ---- ....,.'"...,.'.,...........•.••,•...••..,,,.,.,••~......·.II'cP .... R I V £R :."-'., sus/rNA..----- o 500 l I fEET (Appro •.Scalel SLOUGH 21 Sockeye Spawning Areas VJ 1983 13 1982 [3 1981 '-J N I N N Figure 7-2-8.Sockeye salmon spawning areas,Slough 21,1981,1982,1983. z 2wI- "0cw "(/) II.(/) II.en 0<0 I-a: (IJ 0 <]I'.-, 7-2-23 V1 4- U ooo (Y') N .... ro E V1 r- r- Q) "0o E o..-. '-.J I N I N ~ ~STAFF GAGE --CROSS SECTION I. rn=tI~.i;: Plate 7-2-5.Lower Side Channel 11 modelling site,August 16,1982,mainstem discharge:12,500 cfs. This side channel has been observed to be controlled by the mainstem at discharges as low as 5,000 cfs.Flows in the side channel under contro 11 i ng di scharges have been observed to range from 800 to 4,800 cfs.The initial breaching and controlling discharges for this side channel are the same estimated being at 5,000 cfs.Based on the 30 year historical flow record,the flow in this side channel is controlled by the mainstem more than 99%of the time during the months of August and September (Figure 7-2-2). Chum and sockeye salmon have been observed in this side channel during migration into Slough 11,however no salmon spawning has been documented at the site.For this reason,projections of usable area of spawning habitat at this site were only made for comparative purposes to verify model accuracy. Upper Side Channel 11 Upper Side Channel 11 is located on the east bank of the Susitna River at river mile 136.2 (Figure 7-2-1).It is approximately 0.4 miles in length and is separated from the mainstem by a large vegetated island (Plate 7-2-6).The head of Sl,ough 11 is located on the east side of this side channel,just below its upper confluence with the mainstem. The west bank of the side channel is a low lying,gently sloping, sparsely vegetated gravel bar,as compared to the east bank which is high,steep,and vegetated.A pool/riffle sequence predominates in the side channel except for the lower 500 ft of the side channel where a backwater area predomi nates.Thi s backwater area extends roughly 500 feet into the mouth of this side channel during periods of moderate mainstem discharges.As mainstem discharges increases,the area of backwater increases,inundating the first riffle. The overa 11 grad i ent of the side channe 1 is 23.6 ft/mi as compa red to the overall gradient of the adjacent mainstem of 17.5 ft/mi.Generally, the gradi ent is lower in the fi rst 500 ft of the side channel (11.0 ft/mi)than it is in the remainder of the side channel (21.9 ft/mi). The predominant substrate in the side channel is cobble/boulder interspersed with silt/sand deposits in pool and backwater areas. Prior to overtopping by the mainstem,a base flow of up to 25 cfs in the side channel is provided by local runoff,groundwater seepage,and upwe 11 i ng.Duri ng unbreached peri ods,a normal pool /riffl e sequence exists.Subsequent to overtopping by the mainstem,flows of up to 350 cfs have been observed in the side channel.During this period,the flows in the side channel become controlled by the mainstem and the side channel becomes a long run.The initial breaching and controlling discharges for this side channel are 13,000 and 16,000 cfs, respectively.Based on the 30 year historical flow record,this contro 11 i ng di scharge is exceeded more than 80%of the time in August but only 20%of the time in September,the months of peak spawni ng activity in side channels (Figure 7-2-2). Chum salmon utilize this side channel for spawningl.Observed spawning areas of chum salmon in this side channel are presented in Figure 7-2-9. 7-2-25 ""-J I N I Nen t:::.STAFF GAGE; --~ROSS SECTION Plate 7-2-6.Upper Side Channel 11 'modelling site,June 1,1982,mainstem discharge:23,000 cfs. UPPER SIDE CHANNEL II '-J I N I N '-J flo/:~ EB RM 136 .~.'..~.. ~O' V 0',... .>- ~"'9 -1>,... ~<.<' -1>", ';''7:.-, Chum Spawning Areas rJ 1983 I'ii]1982 f]1981 o 1000 I I FEET (APPROX.SCALE) Figure 7-2-9.Chum salmon spawning areas,Upper Side Channel 11,1981,1982,1983. Side Channel 21 Side Channel 21 is located on the east bank of the Susitna River at river mile 141.2 (Figure 7-2-1).It is approximately 0.9 miles in length and is separated from the mainstem by a series of well-vegetated islands and gravel bars (Plate 7-2-7).Approximately 500 ft downstream of the head,Slough 21 enters the side channel.Additionally,a small unnammed tributary enters approximately 1,500 ft upstream of the mouth. The west bank of the side channel consists of a vegetated,low-lying grave 1 bar with gently s1opi ng banks.Several overflow channels from the mainstem enter the side channel through this gravel bar.In comparison,the east bank is high,steep,and vegetated.A pool/riffle sequence predomi nates in the side channel except for the lower reach where a backwater area predominates.During periods of high mainstem discharge,the backwater extends approximately 1,300 ft upstream from the mouth. The overall gradient of the side channel is 15.8 ft/mi as compared to a gradient of the adjacent mainstem of 13.9 ft/mi.Generally,the middle portion of the side channel has a steeper gradient (l8.7 ft/mi)than either the head (3.2 ft/mi)or mouth (9.4 ft/mi)areas.Cobble/boulder substrates predominate throughout the side channel with silt/sand deposits occurring in pool and backwater areas. Pri or to overtoppi ng by the ma i nstem,a base flow up to 70 cfs in the side channel is maintained by Slough 21,local runoff,groundwater seepage,and upwelling.Subsequent to overtopping t the mainstem enters via an overflow channel below the mouth of the Slough 21.Under these conditions,the side channel flows of up to 1,200 cfs which are controlled by the mainstem have been observed in this side channel. Breaching flows are difficult to assess because of the numerous intermittent overflow channels which connect the side channel with the mainstem.One or more of these overflow channels are breached in the range of mainstem discharges from 9,200 to 26,000 cfs.The controlling discharge that influences the study area is 12,000 cfs.Based on the 30 year historical flow record,the flow in this side channel is controlled by the mainstem more than 90%of the time in August but only 50%of the time in September,the period of peak spawning activity in side channels (Figure 7-2-2). Chum and to a lesser extent sockeye salmon utilize this channel for spawni ng.Observed areas of spawni ng of these speci es in thi s side channel are presented in Figures 7-2-10 and 7-2-11. 7-2-28 -...,J I N I N ~ A STAFF GAGE --CROSS SECTION Figure 7-2-7.Side Channel 21 modelling site,June 1,1982,mainstem discharge:23,000 cfs. / ~/J,- tC"~ ~ ·~:':·:·::'·I., ~·:·"~·;::·:"'····';i:;•. ....~...~' S "';'...".Us ':~../;r-"':'"4-'4 ED 141 SIDE CHANNEL 21 Chum Spawning Areas o 1983 B1 1982 Q 1981 o 500 I I FEET (Appro •.Scal.) ~':':":':"Y-":;'<p"{J;.:j ···n:-··-:·;··..·fI·:;·:..·i.·,...~'...::_. .-······'·.":1 ;c.:, ~'l'''''''~ '-oJ I N I Wo Figure 7-2-10.Chum salmon spawning area,Side Channel 21,1981,1982,1983. / ~ "'?/j/ ~"'? SU S /r /1/4 "-:':,;:,:.:~:.,.."",',.'., •"'C'".,.••,.,,.,•."."""..'••,."•••.•.. ".,.'::"":.,..,'....,:.~",. .".~... -~J~'~~::... ~ EB 14\ SIDE CHANNEL 21 Sockeye Spawning Areas f'J 1983 [2J 1982 o 500 I I FEET (Appro •.Sca',> i;,;,;:':-:,:-'-ii:i";"I;':;···';i'··:i·::(1·:;-:'·I".:~.,:.::~.;•.::•..•.,. :-.:~.~~:I ;:.-:'r, ·~·..·c...··'··ci -...,J I N I W t-' Figure 7-2-11.Sockeye salmon spawning area,Side Channel 21,1982 and 1983. - 3.0 HYDRAULIC SIMULATION MODELS 3.1 Introduction This section describes the data collection and analysis required in the calibration of hydraulic simulation models for selected side sloughs and side channels of the Ta1keetna-to-Devil Canyon reach of the Susitna Ri ver.The models represent the fi rst step of the PHABS 1M mode 11i ng process and are used to predict the spatial distribution of depths and velocities within the study sites over a range of discharges.In Section 5.0,these predicted hydraulic conditions are combined with chum and sockeye salmon suitability criteria developed in Section 4.0 to calculate a stream flow dependent spawning habitat index called Weighted Usable Area (WUA)for chum and sockeye salmon.The hydraulic models were also useo,;'in conjunction with suitability criteria for juvenile salmon to ca1clitlate WUA indices for chinook and chum salmon rearing habitat. This ah~lysis is reported in Schmidt et a1.(1984:Chapter 2). Hydraulic simulation modelling studies were initiated in 1982 as part of the PHABSIM modelling effort.Study sites were located in three side sloughs (8A,9,and 21).In 1983 four side channels (l0,Lower 11, Upper 11,and 21)were added to the PHABS 1M mode 11 i ng effort for the Ta 1keetna-to-Devil Canyon segment of the Sus i tna Ri ver (see Secti on 2.0).Hydraulic data were collected at each study site for model calibration over a range of mainstem discharge and local flow conditions.Because of the influence of breaching and backwater effects on local flow ten hydraulic simulation models (Table 7-3-1)were required at the seven study sites to forecast depths and velocities associated with a broad range of site-specific flows. 3.2 Methods 3.2.1 Analytical Approach Hydraulic modelling is of central importance to the PHABSIM system.The primary purpose of incorporating hydraulic modelling into this analytical approach is to make the most efficient use of limited field observations to forecast hydraulic attributes of riverine habitat (depths and velocities)under a broad range of unobserved streamflow conditions.The IFG specifically developed two hydraulic models (IFG-2 and IFG-4)during the late 1970·s to assist fisheries biologists in making quantitative evaluations of effects of streamflow alterations on fish habitat. The IFG-2 hydraulic model is a water surface profile program that is based on open channel flow theory and formulae.The IFG-2 model can be used to predict the horizontal distribution of depths and mean column velocities at 100 points along a cross section for a range of stream- flows with only one set of field data.The IFG-4 model provides the 7-3-1 same type of hydraulic predictions as the IFG-2 model,but it is more strongly based on field observations and empiricism than hydraulic theory and formulae.Although a minimum of two data sets are required for calibrating the IFG-4 model,three are recommended.Either model can be used to forecast depths and vel ociti es occurri ng ina stream channel over a broad range of streamflow conditions. - ~. Table 7-3-l.IFG-2 and I FG-4 mode 11 i n9 sites. TYPE OF NUMBER -RIVER SITE MILE HYDRAULIC MODEL OF MODELS Sloughs Slough 8A 125.3 IFG-4 2 Slough 9 128.3 IFG-4 1 ~ Slough 21 141.8 IFG-4 2 Side Channels .IIMI; Side Channel 10 133.8 IFG-4 1 Lower Side Channel 11 135.0 IFG-2 1 Upper Side Channel 11 136.2 IFG-4 1 Side Channel 21 140.6 IFG-4 2 ~I The IFG-4 model,which is based upon a greater number of observed sets of field data (i.e.flow levels),generally can be used to model a greater range of flow conditions than the IFG-2 model.Additionally, since the IFG-4 model is more dependent upon observed depths and velocities than the IFG-2 model,predicted depths and velocities can be directly compared with the observed values.This comparison is a useful tool for verifying the models (see section 3.2.4). Both models are most applicable to streams of moderate size and are based on the assumption that steady flow conditions exist within a rigid stream channel.A stream channel is rigid if it meets the following two criteria:(1)it must not change shape during the period of time over which the calibration data are collected,and (2)it must not change shape while conveying streamflows within the range of those that are to be simulated.Thus a channel may be "r igid ll by the above definition, even though it periodically (perhaps seasonally)changes course. Streamflow is defined as "s teady"if the depth of flow at a given location in the channel remains constant during the time interval under consideration (Trihey 1980). 7-3-2 ..,. ,.,.. - - 1'!illI'lMll - In this analysis,all streamflow rates were referenced to the average daily discharge of the Susitna River at the U.S.Geological Survey (USGS)stream gage at Gold Creek,Alaska (Station number 15292000). This location was selected as the index station for several reasons~a long-term streamflow record exists,the gage is located near the center of the river segment that is of greatest interest in this particular analysis,and tributary inflow in the Susitna River between this stream gage and the proposed dam sites is relatively small (estimated as being less than 5 percent of the total flow between the Devil Canyon damsite and the Gold Creek gage,and from 15 to 20 percent of the total flow between Watana and Gold Creek). Site specific streamflow data collected during 1982 and 1983 provided the basis for correlating flow rates through the various study sites to the average daily streamflow of the Susitna River at the Gold Creek gage.Detailed site specific channel geometry and hydraulic measurements provided the necessary data base to calibrate hydraulic models for each study site.Other important physical habitat variables such as substrate,upwelling,and cover were also collected.These data and hydraulic models make up the physical habitat component of the PHABSIM analysis.For a given discharge of the Susitna River at Gold Creek,the flow through each study site can be determined and site specific hydraulic conditions (velocity and depth)can be predicted. These results may be used to forecast the effects of mainstem discharge on the usability of these modelled habitats in the Tal keetna-to-Devi 1 Canyon river segment. 3.2.2 General Techniques for Data Collection A study reach was selected in each of the seven sloughs and side channels for detailed evaluation.Each reach included a minimum of 10 percent of the total 1ength of the study si te with the intent of modelling it to represent the free-flowing portion of that site (ADF&G 1983a:Volume 4). Cross secti ons were located withi n each study reach fo 11 owi ng fi e 1d methods described in Bovee and Milhous (l978)and Trihey and Wegner (1981).Cross sections were located to facilitate collection of hydraulic and channel geometry measurements of importance in evaluating flow effects on salmon spawning and rearing habitats.The slough study sites were established in 1982 and the side channel study sites in 1983. Field data were obtained in 1982 and 1983 to describe a representative spectrum of water depth and velocity patterns,cover,substrate composition,and presence of upwelling at each slough and side channel reach. The number of cross sections established at the study reaches varied from four to eleven.The end points of each cross sections were marked with 30-inch steel rods (headpins)driven approximately 28 inches into the ground.The elevation of each headpin was determined by differen- tial leveling using benchmarks previously surveyed to the project datum 7-3-3 by R&M Consultants,Inc.(1982).Cross secti on profiles were measured with a level,survey rod,and fiberglass tape.Horizontal distances were recorded to the nearest 1.0 foot and streambed elevations to the nearest 0.1 foot •.Water surface elevations at each cross section in the study site were determined to the nearest 0.01 feet by differen- tial leveling or reading staff gages located on the cross section. Streambed eleva ti ons used in the hydrau 1ic models were determi ned by making a comparison between the surveyed cross section profile and the cross section profiles derived by subtracting the flow depth measure- ments at each cross section from the surveyed water surface elevation at each ·calibration flow (Trihey 1980).At the onset of the 1983 field season,discharge data were collected at slough cross sections established in 1982.Depth profiles indicated that the channel geometry did not change significantly from 1982.Therefore,the cross sections surveyed in 1982 were not resurveyed in 1983. A 1ongitudi na 1 streambed profil e (thalweg profi 1e)was surveyed and plotted to scale for each modeling site (Estes and Vincent-Lang 1984: Chapter 2).The water surface elevation at which no flow occurs (stage of zero flow)at each cross secti on in the study site was determi ned from the streambed profile.If the cross section was not located on a hydraulic control,then the stage of zero flow was assumed equal to that of the control immediately downstream of the cross section. Discharge measurements were made using a Marsh-McBirney or Price Aft, velocity meter,topsetting wading rod and fiberglass tape.Discharge measurements were made using standard field techniques (Buchanan and Somers 1969;Bovee and Milhous 1978;Trihey and Wegner 1981).Depth and velocity measurements at each cal ibration flow were recorded for the same respective points along the cross sections by referencing all horizontal measurements to the left bank headpin. Cover,substrate,and upwell i n9 values were also determi ned for each ce 11 along mode 11 i ng transects.Methods descri bed in Schmi dt et a l. (1984)were used to code cover.Substrate categories were classified by visual observation employing the substrate classifications presented in Table 7-3-2.The distribution of various substrate types was indicated on field maps.Substrates were classified using a single or dual code. In those instances that a dual code was used the first code references the most predominant (i.e.,70%rubble/30%cobble =RU/CO). 7-3-4 - - - Table 7-3-2.Substrate classifications. Size (inches) 1/8-1 1 - 3 3 - 5 5 -10 10 Presence of upwelling was determined by examlnlng maps of obvious upwelling locations compiled by the ADF&G during the summer of 1982 and maps of open leads completed during winter flights in 1982-83 at all modelling sites except Lower Side Channel 11 (ADF&G 1983a,b:Appendix C).Upwelling was determined along transects at the Lower Side Channel 11 modelling study side by examining 1983 winter aerial photography. Cells were assigned a value of one in areas where upwelling and bank seepage were observed.Cells in areas showing no open leads or definite upwelling were considered l1 un known ll and assigned an absent upwelling code.The code for absent upwelling was also applied to areas on banks where there was no observed seepage. 3.2.3 General Techniques for Calibration The calibration procedure for each of the hydraulic models was preceded by field data collection,data reduction,and refining the input data. The field data collection entailed establishing cross sections along which hydraulic data (water surface elevations,depths,and velocities) were obtained at different calibration flows.The data reduction entails determining the streambed and water surface elevations,velocity distribution and stage of zero flow for each cross section;and, determining a mean discharge for all the cross sections in the study site.Refining the input data entailed adjusting the water surface elevations and velocities so that the forecasted data agreed more closely to the observed.A model was considered calibrated when:1)the majority of predicted water surface profiles were within ±0.05 ft of the observed elevations and 2)the majority of predicted velocities were within ±0.2 ft/sec of the measured velocities.A calibrated IFG-4 model gives velocity adjustment factors in the range of 0.9 to 1.1,and relatively -few velocity prediction errors.The velocity adjustment factor is the ratio of the computed (observed)discharge to the predicted discharge. 7-3-5 An IFG-2 model does not have velocity adjustment factors and must be reviewed with the observed data before its considered calibrated. 3.2.4 General Technigues for Verification The IFG recommends an extrapolation range of 0.7 times the low flow to 1.3 times the high flow for a two-flow IFG-4 hydraulic model.For a three-flow IFG-4 hydraulic model,an extrapolation range of 0.4 times the low flow to 2.5 times the high flow is recommended.The extrapolation range for an IFG-2 hydraulic model is from 0.4 to 2.5 times the calibration flow (Milhous et ale 1981). Preliminary results following the IFG guidelines for model calibration did not always ensure a reliable hydraulic model.Therefore,in addition to the IFG guidelines,two other techniques were used to evaluate how well the calibrated models could forecast observed relationships or measurements.The first technique,diagrammed in Fi gure 7-3-1,i nvo 1ved a compari son of observed and predi cted water surface elevations for a single cross section in each study reach.The second technique,involves a comparison of observed and predicted depths and velocities. As part of an investigation of the relationship between mainstem discharge and site specific flows (Estes and Vincent-Lang 1984:Chapter 1),periodic discharge and water surface elevation measurements were obtained at cross sections located within each study reach in order to develop site specific rating curves.The regression lines developed independently from rati ng curve and modell i ng data were stati sti ca lly tested for coincidence;that is,their slopes and intercepts were tested for equality. Analysis of covariance (ANACOVA)was used to first test the hypothesis that slopes were equivalent.The model associated with this test is denoted by: (lwsel)..=G +A.+Bl (lflow)..+B2 (lflow ..*type.)+E..lJ 1 lJ lJ 1 lJ where: i =1,2 (I=IFG model output,2=observed data); j =1,...,ni (sample size for data set of i); lwsel =base 10 logarithm of water surface elevation; lflow =base 10 logarithm of site flow; type = 1 or 2 if data from IFG analysis or observed data; 7-3-6 - - MODEL VERIFICATION TECHNIQUE -Obtain Site Specific Calibration Data For IFG Model Calibrate IFG Model Predict Water Surface Elevation at ADF&G Cross Section in Study Site for 3 to 5 Flows Obtain Many Periodic Water Surface Elevations and Flow Measurements at One Cross Section in the Study Site Plot Water Surface Elevation Versus Flow and Determine Best Fit Regression Line Through Data Points Plot Best Fit Line Represented by Regression Equation / - Plot Predicted Water Surface Elevation Values Forecast by IFG Madelon ADF&G Regressi on Li ne Figure 7-3-1.Flow chart for comparing model predicted water surface elevations with site specific water surface elevations-versus-discharge curves developed by ADF&G 7-3-7 G =common intercept parameter; A.=intercept parameter associated with type of 1 data; B1 =common slope parameter; - B =slope parameter associated with type of data;2 -and, E =error term.~: The hypothesis tested is: If the results of this test indicated that the slopes were ~quivalent (i .e.fail·to reject H ),then an additional ANACOVA was used to test the hypothesis that in~ercepts were equivalent.The model associated with this test is: 2)(lwsel)..=G +A.+B1 (lflow)..+E.. lJ 1 lJ lJ where the symbols are equivalent to model number one (above). -. """' The hypothesis tested is: HO:Al =A2; Ha :Al "I A2• If we fail to reject Ho 'then intercepts are equivalent. 7-3-8 - ,flI"C'. -, - - Both ANACOVA test statistics were calculated according to the procedures outlined by Ott (1977)and carried out on a microcomputer-based statistical package (SPSS/PC,SPSS 1984).If both hypotheses are not rejected then it may be assumed the two sets of data represent the same water surface elevation versus discharge relationship. The second evaluation included a comparison between scatter plots of observed and predicted depths and velocities at all cross sections for each observed calibration flow.These scatter plots were used to visually evaluate the reliability of the models in predicting depths and velocities.Predicted depths and velocities are additionally classified as being outside arbitrary cutoff 1imi ts whi ch denote that they are comparatively poor predictions.The cutoff limits are defined as the larger of two criterian: 1)±25%of the observed value;and 2)±0.05 ft or ft/sec for depth and velocity,respectively. The cutoff limits are plotted'on each scatter plot as cone-like lines on either side of a one-to-one line (denoting complete accuracy;i.e., observed =predicted).The proportion (as a percent value)of values predicted values outside of the cutoffs compared to all predicted values was used to evaluate the reliability of the model to predict accurately depths and velocities. 3.3 Results 3.3.1 Slough 8A (River Mile 125.3) 3.3.1.1 Site Description A 1,000 foot long multiple cross section study site was established in Slough 8A in July 1982 (Plate 7-2-1).The study site represents typical pool/run habitat in Slough 8A that continues from the study site upstream to the head of the slough.The study site is not representa- tive of the beaver pond and backwater habitats found downstream of its location.Eleven cross sections were surveyed to define channel geome- try for the use with the IFG-4 hydraulic simulation model (Figure 7-3-2).Cross sections 1,3,and 7 are located in transition areas between adjacent pools and riffles.Cross sections 2,5,8,9,la,and 11 define pool areas and cross sections 4 and 6 describe riffles.A beaver dam constructed between cross sections 3 and 4 during the later portion of 1983 field season has considerably altered the slough hydraulics.The dam did not adversely affect the quality of the data used to calibrate the IFG-4 model because it was constructed after the last data set was obtained. 3.3.1.2 Data Collected Mean daily discharges for the Susitna River on the dates that calibration data were collected at the Slough 8A study site were determined from provisional USGS streamflow data for the Gold Creek Station recorder (Table 7-3-3). 7-3 -9 ~ .........,.,D'••CROSS SECTION .76 CROSS SECTION 3 07•Slatian 30+IS.. ~.n z 070a S •••>-_53-;h........_1geh..-.......;:.Tel•..•••~c:h =>II:........ 20 40 fOO 80 100 120 140 leO 180 HORIZONTA~DISTANCE (rootl -. - - - .76 CROSS SECTION-'7'Station 28 +14.. ~.n z 070a ~•••~__!o3Cf.....,~1gef....-=1;f•..•••4eh..=>•••II:.. "0 CROSS SECTION 4 Station :31+47 .0 o@.O 60 ao 100 120 140 HOR'ZONTA~DISTANCE (Iootl 100 110 07' !57, Z 'n 0 070~~'0'............'0,=> II:'0'.. '00 0 .0 40 60 80 100 12Q 140 HORIZONTAL DISTANCE croor] "0 100 - 570 CROSS SECTION Z 51.station 29+25 !51. Za 510;:: ~..,.._53-cf....'00 lich..1e'...4cf. =>II:..... "0 .0 '0 00 'DO , 120 140 180 ISO 070 CROSS SECTIDN 5 ~07' Slation 32+36 '"~070~~..................:> II:'02.. "0 '0 .0 .0 .0 100 120 1'0 l'SO 110 - HORIZONTA~DISTANCE (foot I HORIZONTA~DISTANCE «toot I Figure 7-3-2.Cross water of 4, sections for Slough SA study site depicting surface elevations at calibration discharges 7,19,and 53 cfs. 7-3-10 - - HO CROSS SECTION 6 '70 CROSS SECTION 9·.7.Slation 33+02 ·'74 Slation 36 +22·:~ 07.Z '72Z 5!"'a C>;:::·~70~~53ch~5 •• =--------lS3cfs...50•~19Ch..-'7efs-'5. __19crs. 4<:h..~l~~:..,....5. ..:::>...:::>'"'"56.~.E>~ '60 "0 , ,~.0 .0 00 00 '00 "0 ,..160 100 .0 .0 '0 .0 '00 "0 "0 160 180 HORiZONTAL DISTANCE ( '••tl HORIZONTAL DISTANCE ('ull 076 CROSS SECTION 7 07. Station 33+43··!57'? ZC>070~,..53ch..#19'"-'566 7ch..4<:14..,..:::> '"56,?;~ 56 076 CROSS SECTION 10·".Stotion 37+35·~ Z 57. C> ~"a >...~~~~::..=--::::::::::.1ef'S.-'..,..4 cfs.. '6':::> '"~.6. ..0 .0 .0 .0 BO 00 "0 160 "0 .0 .0 .0 .0 '00 <20 "0 ,.0 "0 HORIZONTAL DISTANCE U ••ll '7&CROSS SECTION 6 07.Station ~4+46··•72 Z 0702 §....::::::?-r;~:: ..6 -..........7'ct....4ch.....:::> '"'5'~ '60 20 40 60 80 100 12:0 140 HORIZONTAL DISTANCE (f••t) HORIZONTAL DISTANCE (fooll 076 CROSS SECTION II ".Station 36 +23··07• Z C>.70S'6B ~~~~::>..~7ch -'5e6 4ch....5154:::> '"~.6. '6 160 "0 .0 .0 60 .0 100 ,.0 140 lOa '.0 HORIZONTAL DISTANCE [f••1l - Figure 7-3-2.(continued). 7-3-11 *Table 7-3-3.Calibration data collected at Slough 8A study site...... - Date 820822 820907 820917 830604 Site Specific Flow (cfs) 4 7 19 53 Susitna River Discharge (cfs) 12,200 11,700 24,100 36,000 ,..", *Controlling discharge is 33,000 cfs. 7-3-12 - - - ,~ 3.3.1.3 Calibration Calibration data were available at the close of the 1982 field season for slough flows of 4,7,and 19 cfs.An IFG-4 model was used to fore- cast instream hydraulics based on these calibration flows.The water surface profile at a slough flow of 50 cfs was selected as the upper limit of the extrapolation range for this particular model using the criteria suggested by the IFG (Bovee and Milhous 1978).The streambed profile,stages of zero flow,and observed and predicted water surface elevations for the study reach are plotted to scale in Figure 7-3-3. Because the 19 cfs data set was collected when the slough was not breached by the mainstem,an additional data set was needed to explain the channel hydraulics during breached conditions.A fourth data set was collected during the 1983 field season at a slough flow of 53 cfs. All four data sets were used to predict water surface profiles for slough flows between 4 and 125 cfs.These forecasts are compared to observed water surface profiles and are plotted to scale ill Figure 7-3-4.The predicted profile for 125 cfs is unreasonable because the water surface profile flows uphill from cross section 7 to 4.A significant difference was observed between the observed and predicted water surface elevations occurs for each calibration flow at the first seven cross secti ons.Thi s di screpancy is due to backwater effects occurring at the site when the northeast channel is breached.This situation was modelled by using two IFG-4 hydraulic models;one with backwater effects in the lower half of the study area and the other without backwater effects.The 4,7,and 19 cfs data sets were used to calibrate a hydraulic model capable of simulating flow conditions without backwater effects (Figure 7-3-5)and the 19 and 53 cfs data sets were used to calibrate a model for use when backwater effects are present (Figure 7-3-6).. To evaluate the performance of the calibrated IFG-4 hydraulic models, observed and predicted water surface elevations,discharges,and veloc- ity adjustment factors were compared (Appendix Tables 7-A-l and 7-A-2). The maximum difference in water surface elevations for each calibration flow was 0.02 ft at the 11 cross sections.The mean calibration discharges predicted by the low flow models were 4,7,and 20 cfs, respectively,and the mean cal"ibration discharges predicted by the high flow models were 19 and 53 cfs,respectively.The velocity adjustment factors for both models range from 0.95 to 1.03,indicating the models are suitably calibrated (Milhous et ale 1981). 3.3.1.4 Verification For Slough 8A,the three-flow model (4,7,and 19 cfs)describing the hydraulic conditions without backwater effects has an extrapolation range of 4 to 20 cfs.At slough flows below 4 cfs,the depths become so sha 11 ow in the wi de rectangul ar-shaped cross secti ons that accurate velocity readings are difficult to make.Therefore,the hydraulic model was not extrapolated below the measured 4 cfs slough flow.·Backwater effects become present in the study site when the northeast channel is breached at sloUgh flows of 20.to 30 cfs.Accordingly,the upper extrapolation limit of the low flow hydraulic model is 20 cfs.This corresponds to Susitna River discharges at Gold Creek of less than 7-3-13 568 SLOUGH SA \I CROSS-SECTION NUMBER 10 37+38 38+23 8 38+22 8 LEGEND ADf a G SU HYDRO,1983 •Observed Water Surface Elevation Prill iminary Simulated Water Sudace Elevation Elevotlon of Zero Flowc=::::::::J 5 i It I Son d r:::=:::=J Grovell Rubble 34+48 /---,--<:,-:'~:::_----~;::::-- ___/---<.--.;-;,Jo ---~~-~---. -",",/---------y-,//--~---:~- ----------/--~--------;:---::"'~_/-. •l~<!'--_-/-_..--:::~-.;-.;---7 L __J_'!'r ----...----------------"'""r---------..----~-------....4~"-r -0".-__----A:>:,T"C:-:':::;:'Lt>'::;.~::i:;!';::(;i:!i;,!::;~ 567 D66 &62 &63 I I I I I 661'I I I I I I &64 &6D .....-III III........ z 0 !;( > l&.I ..J ......, l&.I I W l&.I ::l I--' Q:: +::> I- STREAMBED STATION (feet) Figure 7-3-3.Comparison of observed and predicted water surface profiles from non-calibrated model at Slough 8A study site. J .1 ]~1 I J I ,J 1 J I J J ~.J J >1 -J _.~-J 1 1 1 J J 1 1 1 CROSS-SECTION NUMBERII10 37+35 38+23 9 --------_.....--- 36+22 LEGEND •Observed Water Surface Elevation Preliminary Simulated Water Surface Elevation Elevation of Zero Flowc=J Silt/Sand 1.,;:-,:~I Gravell Rubble AD f a a SU HYDRO ,198! 3 SA 2 29+25 30+111 SLOUGH :i~;i;t{;J@J~U/' __125 cfs ....-_________----___--~~~111"------.----------------....,....--------:~........_....~...- - ----.----. !.,,,,,"".•/__-a:---------~ _____________------I!......_J--------~------....-----...---.--_.....-,,-:--'---_~......' 19cf ;-;-------.----1--...._; _____s --;-...;:.-....-L--------I'.".• • •;;-;-_!..--_"'~~==~~~-~_-_-----~~::-----"----;:~:;{i;;i:[ta;!;f;\'iri{\T;:~;;::l)l:!;'W!:t<i{;!~f; i::->~:....~.;...,:: 281"14 562 561'I I I I I I I I I I I 563 565 566 564 568 567 .... III III........ z 0-r c( >W ...J W -....J W !::J W I 0:: I--'r U'1 STREAMBED STATION (feet) Figure 7-3-4.Comparison of observed and predicted water surface profiles from non-calibrated model at Slough8A study site. 568 SLOUGH 8A CROSS-SECTION NUMBERII10 37+315 381"23 9 361"22 ] Extrapolation .--•Range of::....d": •Hydraulic Madel 8 •ObHrved Water Surface Elevation --Simulated Water Surface Elevation ----Elevation of Zero Flow [::O-"":J silt I Sandr::::::::::::J Gravell Rubble ADF a G SU HYDRO,1983 LEGEND 34+46 7 " ,;;!:;~}[':~;~;::~~~::;:::--;-<:::;',:;:;;::::<'A:;,;-u> ~:.:,-.:, '"':;~'::..... .;~:~:. .'.;':,~" 4 31t47 32 29+25 30+-1528tl4 ::\~X:~}{::'~Z:H;:/ 190fs ••..- 7cfs ••::: 4cfs •• 565 562 564 566 563 561 'I I I I I I I I I I I 567 --... Q) Q).... ~ Z 0-.... e:( > W -I ""-J LLl I W WI I-';:) O'l lr.... STREAMBED STATION (feet) Figure 7-3-5.Comparison of observed and predicted water surface profiles from calibrated model at Slough 8A study site for low flow regime I )i i )I t ,J I I t !]J j Jl )1 --;1 )-:)1 -I j 1 J 1 II II CROSS-SECTiON NUMBER 10 37+35 38+23 9 36t22 ADF&G SU HYDRO.1983 LEGEND •Observed,Water Surface Elevation --Simulated Water Surface Elevation ---Extrapolated Water Surface Elevation ---Elevation of Zero Flow I'.'.Silt/SOlid c:::::J Grovel/Rubble c;;l~?;'8rKs,,-::Si;!;'?:;,}:i;:::?V;i:);:gj!'i!i;;4,' ::.:~:~>: ."'.. .....,.~.; "...~ ',J'~;o .., ...l,.",,'; ",.-.-";.'.:.~ ",:.,.. '''>."1.:'; 32 29t25 30tl5 ,':-::::.~,~>t,;:·:y;)\; .."~... 19cfs SLO UGH 8A ._-~-~}Extropololi?n Range ~of H,d""'"Mo'" ___70cfs_________------- •53cfs...,. 28tl4 563 565 564 566 561 I I I I I"""I I I I I I 562 568 567 --.. II II........ z 0 ....« > LtJ .J ......, LtJ I W LtJ I ::J ......."......,.... STREAMBED STATION (feet) Figure 7-3-6.Comparison of Observed and predicted water surface profiles from calibrated model at Slough 8A study site for high flow regime. 33,000 cfs.The two-flow model (19 and 53 cfs)describing the backwater effects has an extrapolation range from 20 to 70 cfs.Insufficient data were available to define a relationship between slough flow and mainstem discharge when the northeast channel was breached. A comparison was made between water surface elevations predicted by the IFG-4 hydraulic model for Slough·8A and those observed at the gaging site Figure 7-3-7.The stream gage is located 4000 ft upstream from the study site at a 1.4 ft higher bed elevation but with a similar cross sectional shape as that of cross section 11 within the study site. Therefore,the rating curve for the stream gage does not have the same y-intercept as the curve for cross section 11 but they should have similar slopes.The analysis of covariance (ANACOVA)results indicated that the slopes of the two curves are equivalent (Appendix Table 7-A-3). As expected the intercepts of the two curves were di fferent (Appendi x Table 7-A-4).Because the slopes were not different,the model was considered to be adequately calibrated.There was insufficient data available to develop an empirical rating curve above 19 cfs slough flow. Therefore,the two poi nt hi gh flow model for Slough 8A cou 1d not be statistically tested. Comparison of observed and predicted depths and velocities for the three point low flow model for Slough 8A indicated that the model predicted depths quite accurately (Appendix Figure 7-A-l).The predicted depths were highly correlated with the observed values (r=0.99)and 160 predicted values out of a total of 1115 depths (or 14%)w,ere considered to be outside the arbitrary cutoff limits.Predicted ve loci ty values also compared favorably wi th observed va 1ues (r=O.99), with 38 values of 1115 (or 3%)considered to be outside the cutoff limits.A few of these 1I 0u tside ll predicted velocities were substantially different that the observed values.These all occurred for observed velocity values of 0.0 ft/sec. Depths preqicted by the two point high flow model also compared favorably with the observed values (Appendix Figure 7-A-2;r=O.99).A total of 188 predicted depths were considered outside of cutoff limits out of a total of 811 values (or 23%).The number of poor predictions for velocity values (32 of 811,or 4%)was similarly low.However,some of these lI ou tside ll value were far outside the cutoffs.Most of these extreme values were associated with the 53 cfs calibration flow level. 3.3.1.5 Application The study site in Slough 8A was chosen to represent typical spawning and rearing habitat in the free-flowing portion of this slough (Estes and Vincent-Lang 1984:Chapter 2,Figure 2-13).The study site is located approximately 900 ft upstream from a large beaver dam that existed prior to the 1982 field season.Because of the pronounced effect of backwater from the beaver dam associ ated with breaching f1 ows at the study site,high and low flow hydraulic models were calibrated to represent the hydraulic conditions with and without backwater effects. The high flow model was based on calibration flows of 19 and 53 cfs. This model was well calibrated,but should be applied with caution.Due 7-3-18 - ]i 1 j J )J }J ] ---------.-----~------.--~------~---.--.I.. I I --CD CD....-za-~>W ...J W L&J 0 If 0:: '-J ::JI W C/)I I--' 0::I,Q W ~ ~ 575 574 573 572 571 570 569 588 587 &68 565 584 583 562 Extrapolation rang~of low flow model. Extrapolation range I of high flow model LEGEND -Rating curve from observed water surface elevations and discharge measurements at R aM stream gage 1000 ft. upstream of study site.. -"-Predicted water surface elevations from calibrated hydraulic models at cross section'II. 561 -1""'.""'.----.....,....---r,--"I',-....,-~,...."I',-...,...,....,-----.....,....--....,--..,-....,-..,-..,-,.....,..., 2 4 6 8 10 20 40 60 80 100 SLOUGH 8A NE CHANNEL 0 I SCHARGE (cfa) Figure 7-3-7.Comparison between ADF&G rating curve and model predicted water surface elevations. to the significant influence of backwater effects at high slough flows that can not be adequately modeled with out additional data,it is recommended that the model not be used for slough flows greater than 70 cfs.The most appropriate use for this model is to forecast depth and ve loci ti es occurri ng between streambed stati ons 27+00 and 40+00 when slough flows are between 19 and 70 cfs.Slough flows occur in this range when the northeast channel is breached which·corresponds to mainstem discharges greater than 33,000 cfs. The low flow model was based on calibration flows of 4,7,and 19 cfs. It is capable of providing reliable estimates of depths and velocities for s10ugh flows between 4 and 50 cfs provided that no backwater effects exist.This model is most suitable for forecasting hydraulic conditions for non-breached conditions throughout the free flowing portion of the slough.At flows of less than 4 cfs,significant differences were noted between forecasted and observed depths and velocities,indicating that the predictive capability of the hydraulic model is diminished at extreme1y low flows (very shallow depths in a wide channel).This result is due primarily to modelling limitations along the channel margins and in shallow-low velocity areas. 3.3.2 Slough 9 (River Mile 128.3) 3.3.2.1 Site Description The multiple cross section study site in Slough 9 was established in July 1982 (Plate 7-2-2).Ten crOss sections were initially surveyed to define the channel geometry for the 1,160 ft study reach (Figure 7-3-8). The streambed elevations for cross section 7 were not measured by ADF&G but were obtained from R&M Consultants,Inc.,who had previously established a discharge site at the same location.Cross sections 1,7, 8,9,and 10 describe pool areas.Cross sections 2 and 6 define transition areas between adjacent pools and riffles.Cross sections 3, 4,and 5 cross a riffle and are similar in shape.Cross sections 3 and 5 were not used in the hydraulic model but were surveyed to evaluate passage conditions for adult salmon.Cross section 4,located across the midd1e of the riffle,was used to define hydraulic conditions in the riffle for the entire flow range being simulated. 3.3.2.2 Data Collected On the dates that calibration data were collected at the Slough 9 study site,corresponding mean daily discharges were determined for the Susitna River at Gold Creek.The discharge data collected is listed in Table 7-3-4. 7-3-20 - - ...... *Table 7-3-4.Calibration data collected at Slough 9 study site. Site Specific Flow Susitna River-Date (cfs)Discharge (cfs) 820904 8 14,400 830818 30 21,000 830607 89 23,000 820920 148 24,000 820918 232 27,500 *Controlling discharge is 19,000 cfs. 3.3.2.3 Calibration Calibration data were available at the close of the 1982 field season for slough flows of 8,148,and 232 cfs.An IFG-4 model was used to forecast hydraulic conditions present at these flows.The water surface profile for a slough flow of 600 cfs was also forecast to evaluate the predictive capability of the model at the upper limit of the extrapo- 1ati on range.The streambed profi 1e,stage of zero flow and observed and predicted water surface elevations for the study reach using the 1982 data are plotted to scale in Figure 7-3-9. An IFG-4 model developed from data collected at 8,148,and 232 cfs did not provide an accurate description of the hydraulic conditions observed at this study reach.Representative velocity data were needed for slough flows between 8 and 148 cfs.Due to the large difference in wetted channel that exists between these flows,data were collected at 30 and 89 cfs during the 1983 field season.However,the 30 cf~data were found to be in error and were not used in the hydraulic model . During the 1982 field season,a large sand berm present near the head of the slough was breached by a high flow event that occurred in mid-September.A layer of sand was deposited throughout the slough which caused the water surface profile at 89 cfs to be nearly identical to that which existed in 1982 for a slough flow of 148 cfs (Figure 7-3-10).The three-flow model was used to forecast a slough flow of 90 cfs and a comparison was made between the observed depths of flow at 89 cfs (1983 data)and the predicted depths of flow for 90 cfs.These flow depths were found to be quite similar even though the predicted water *A review of the data collected for the 30 cfs measurement revealed di fferences in di scharge .estimates between cross secti ons whi ch exceeded 200%.The velocity measurements obtained in the lower half of the study site were believed to be in error due to equipment failure.Therefore,the 30 cfs calibration data set was not used in the hydraulic model. 7-3-21 - 61'CROSS SECTIO ... S,otion 16-1-47 60. !..,. zsa 600~>.. oJ .....232.ch..i48ch :::I •••eVeh 0:'--8th l-... I 20 40 60 ao 100 1,,0 140 160 f80 200 220 240 HORIZONTAL DISTANCE U••U 6"CROSS SECTION 2 Sto1ion 19+42 !60. Z 6040 ~... 600> III oJ III .9. III :::I II:..,..... .0 40 60 .0 100 '.0 140 '.0 leO .00 2iLQ .40 HORIZONTAL DISTANCE U ..l1 CROSS SECTION 4 Station 20 ..00 Z .04o ~~ ~ l6!5916.. :::I II:59i! I- ,••,;......,......,........I"""-,.......,.....,..""".....,...,"""l''"''I'....,....''''''.., 2.0 40 &0 80 100 120 1"0 1&0 180 2.00 Z20 240 HORIZO...TAL DISTA ...CE 1100'1 61'CROSS SECTIO...6 10 SITE Sration 21+77.60•.-Z 604 0 ~ ~600.. oJ III ... III :::I II:... I-... 20 40 60 60 100 120 140 160 Ul:O 200 220 240 HOR IZONTAL 0 'STANCE cr ••,I ..,. Figure 7-3-8.Cross water of 8, sections for Slough 9 surface elevations at 89,148,and 232 cfs. 7-3-22 study site depicting calibration discharges - - ... 6'2 CROSS SECTION 7 6'2 CROSS SECTION 9 Station 22 +93 Statian 261-48•608 .80B ~~ 600 Z 604 Z 02S!C 600 600 >~III oJ oJ .9.III ••6 III 23Zcfs _232cfs;III ~14ec.fs III 1481:f$---.!:~::'"'~9cf''"••2a:••2 8ch a:.... '.8 ••• a 20 00 60 80 100 120 '00 ISO 180 200 220 240 20 00 60 80 100 120 '00 '60 180 200 2.2'0 2 ..0 HORIZONTAL DISTANCE I f ••t)HORIZONTAL DISTANCE (f..11 •..-"'.,...,..........!""'I..,..,.................I""'I..,..,....""I""....I""'I..,....., o 20 40 60 eo 100 120 140 160 ISO 200 220 240 HORIZONTAl..DISTANCE (f••tl CROSS SECTION 10 Station 28 +06 600 .0. ... .'2 Z 604 o ~ III oJ III III '"~ •606 ~ , 20 40 60 eo 100 120 140 160 180 200 220 240 HORIZONTAl..DISTANCE (f..'l CROSS SECTION 8 Slation 24+80 .'2.600 ~ Z 604 ~..600cr>~...III III '".92a:..... i""'", Figure 7-3-8.(continued) - 7-3-23 596 SLOUGH 9 _~------~-----------1r---------~-----------~----- • _.- c:::::IJGravell Rubble .•.."::;'.:.;.;. L ~~---,-A:..:D:..:F,-=a,--G=--=-s-=-U_H---,-Y-=-D:..:R-=O:..:.,-1_9..:8..:3---,--,.,o"~:; ----~~~~~-------------_/'---------~~~~~~~=-~~;~-~~~~~~~~~~~~~~~~~~~~;;;=-;--~;;;;;=: ---_......-__-11---......_232cfs ...-_- .---------~------•__J~B_C..!!L ---------..- • 592 594 590 591 595 593 --III III-.... Oil!: 0-I- et> IIJ .J IIJ IIJ ""-J ~ I It:W I l- N ~ I I I I I589'I I I 2 4 6 7 8 9 10 CROSS-SECTION NUMBER 16+47 19t42 2Ot00 21+77 22+93 24+80 26 ...48 28+06 STREAMBED STATiON (teet) Figure 7-3-9.Comparison of observed and predicted water surface profiles from non-calibrated model at Slough 9 study site. ]J J .,J ,)J J J i I I J •; ]i 1 )J -J 1 1 I l 1l91l SLOUGH 9 ~---------------------- ..------------------------ LEGEND _1962 S"eQrnbed PrQIi 'e ---1963 S"eQrnbed Profile' ----1982 Observed Water Surface EleVQlion -----1983 Ob58rvilild WQ'er Surface Elevation __-_8"":':"--"...., //--->~..- 2320fs /~---------"'=""-=--.....~-----.~~----=_-=-~-="3"--:::~--;::-=':::--------,------------~-=---= Iq6 cfS 590- 591 592 - 1193 - 1194 ~........ ~ z 0 I-«;;- UJ ..J l&.I .......UJ I ::J W a: l- N CJ1 589 'I I I I I I I I ,I 2 4 6 7 8 9 10 CROSS-SECTION NUMBER 16+47 19...42 20+00 2'1'77 221'93 24 ...80 26...48 28 ...06 STREAMBED STATION (roet) Figure 7-3-10.Comparison between 1982 and 1983 streambed and water surface profiles at Slough 9 study site. surface prof'j 1e for 90 cfs was lower than that measured for a slough flow of 89 cfs.It was also noted that the sand deposition had not drastically altered the cross sectional shape of the study site. Because the cross sectional shape of the channel and the depths of flow were similar,it was assumed that the velocities measured in 1983 at a slough flow of 89 cfs were of the same magnitude as vel ociti es that would have been measured at a slough flow of 89 cfs in 1982 had such a slough flow occurred that year. The 90 cfs predicted water surface profile was then used with the 1982 depth and velocity data collected at a slough flow of 89 cfs and combined with the three data sets to form.a four-flow model.The water surface elevations predicted by the hydraulic model are plotted to scale in Figure 7-3-11. To evaluate the reliability of the calibrated IFG-4 hydraulic model for Slough 9,observed and predi cted water surface e 1evati ons,di scharges and vel oci ty adjustment factors were compared (Appendi x Table 7-A-5). The maximum difference in water surface elevations for each calibration flow was 0.06 ft'at the eight cross sections.The means of the calibration discharges predicted at each cross section by the IFG-4 hydraulic model were 8,89,148,and 232 cfs,as compared to means of 8, 88,148,and 234 for observed values.The velocity adjustment factors range from 0.96 to 1.04,indicating an acceptably calibrated model. 3.3.2.4 Verification for Slough 9,the four-flow model (8,89,148,and 232 cfs)describing the hydraulic conditions has an extrapolation range from 5 to 600 cfs. At slough flows below 5 cfs,the depths become so shallow in the wide rectangular cross sections that accurate velocity readings are difficult to make.Therefore, the hydraulic model was not extrapolated below 5 cfs.Slough 9 is mainstem controlled at Susitna River discharges near 19,000 cfs.The Slough 9 model can forecast hydraulic conditions in the study site for Susitna River discharges at Gold Creek up to 30,200 cfs (figure 7-3-12). A comparison was made between water surface elevations predicted by the IfG-4 hydraulic model for selected flows at the discharge cross section and the rating curve developed by ADF&G for the same cross section (Figure 7-3-13).The analysis of covariance results indicated that the two curves had equivalent slopes and intercepts (Appendix Tables 7-A-6 and 7-A-7).Accordingly,the model was considered to be adequately calibrated. Predicted depths from the Slough 9 model compared quite well with observed values (Appendix figure 7-A-3;r =0.99).Only 109 of a possible 1485 (or 7%)predicted values were considered to be poor predictions (i.e.outside cutoff .limits).Similarly,predicted velocities compared well with observed values.Ninety of a total 1485 (or 6%)predicted values were considered poor predictions.As with the high flow slough 8A model,a number of these poor predictions were substantially different than the observed values.These extreme values occurred for all observed flow levels except for tne 8 cfs level. 7-3-26 - - - -J 1 1 ]J --J 1 J J )}1 596 SLOUGH 9 Ektrapalalion Range of Hvdraulic Model .,.--------------------------600 cfs .~:::: 232 cis ...-• 148cfs ~~-_~~~~~~~~.~~~~.:--------.. '9,1'~_~_Y--_--_ 8cts _~ =--"..--;·f~t:t;;1:[(?'" ~LEGEND •Observed Water Surface Elevation --Simulated Water Surface Elevation ---Extropolated Water Surface Elevation ---Elevation of Zero FlolII [::J Silt;Sand C3Gravel ;Rubble 590 592 595 593 594 591 -Q) GI.... ~ z 0 t-«> LLI ...J LLI '-l LLI I :::l W a:: I l- N '-l ADFa G SU HYDRO.1983 987642589'I I I I I I I 10 CROSS-SECTIONINUMBER 16+47 19+42 20+00 21+77 22+93 24+80 26+48 28+06 STREAMBED STATION (feet> Figure 7-3-11.Comparison of observed and predicted water surface profiles from calibrated mOdel at Slough 9 study site. 1000 900 800 700 600 !SOO -fI)..100 U 90-80 3=70 60 0 !SO..J LL 40 en 30 ~ (!)20 ::> 0 ..J en 10 9 8 7 6 !S 4 3 2 ADF BG Flow Versus Discharge Curve for 5 loug h 9 QSL:=10-37.7897(QMs)9.0!S58 .~ (J9,000,9 ) Slough f low determined by local runoff and upwelling for mainltem dilcharge below Q breoc:hing dilcharg.e of 19,OOOctl. LEGEND •Coincident moinstem discharge and slough flows at which calibration data were collected. (30,200,600) Recommended Extra- polation Range of the ~Hydraulic Models under Mainstem Con- trolled Discharges . - - - - - - 2 MAINSTEM DISCHARGE AT GOLD CREEK (x IOOOcfs) Figure 7-3-12.Relationship between extrapolation range of the Slough 9 model and ADF&G flow-versus-discharge curve. 7-3-28 -l J 1 -1 --I J 1 1 J -1 1 1 J 1 591""1 iii iii iii iii iii iii iii i I I ill I I \...Extrapolation 0 range of mode I ..I I I I 200 -Rating curve from observed water surface elevations and discharge measurements at ADF 8G staff gage 128..3 S I •Predicted water surface elevations from calibrated hydraulic model. ...... LEGEND 40 60 80 100206810 .... 42 593 592 596 595 594 604 603 602 601 600 598 -..••...-·z0-ti~ ...J LIJ Ia.I 0 if 0:: '-J ::::)•w (J) I N 0:to l&J ti 3C S LO UGH 9 0 ISC HA RGE (c f 8 ) Figure 7-3-13.Comparison between ADF&G rating curve and model predicted water surface elevation. 3.3.2.5 Application The study site in Slough 9 was chosen to represent typical spawning and rearing habitat in the free flowing portion of the slough (Estes and Vincent-Lang 1984:Chapter 2,Figure 2-15).In general,the free flowing portion of Slough 9 extends from streambed station 6+00 to 35+00 for unbreached conditions and 8+00 to 60+00 when breached.Downstream of streambed station 6+00,depths and velocities within the slough are more significantly "influenced by mainstem backwater effects than by slough flow.Hence,the Slough 9 hydraulic model should not be applied to this portion of the slough. The Slough 9 hydraulic model will forecast depths and velocities for slough flows between 30 and 600 cfs which correspond to a range of mainstem discharge between 19,000 and 30,200 cfs.Below 19,000 cfs,the slough flow ranges from 3 to 30 cfs.Strict application of IFG guide- lines for the recommended extrapolation range would indicate the model is applicable to a range of slough flows between 3 and 580 cfs.A comparison was made between depths and velocities forecast by the model for a slough flow of 3 cfs and a data set collected August 25;1982 by ADF&G when the measured slough flow was 3 cfs.As with the Slough 8A low flow model,the reliability of the hydraulic model rapidly deterio- rates when simulating extremely shallow depth associated with low slough flows.Therefore,a lower extrapolation limit of 5cfs is recommended. 3.3.3 Slough 21 (River Mile 141.8) 3.3.3.1 Site Description Initially,eight cross sections were established in July 1982 to define the physical habitat conditions present at Slough 21 (Plate 7-2-3, Figure 7-3-14).Cross section 3 defines the transition area between an adjacent pool and riffle.Cross sections 4,5,6,and 7 describe pool areas.Cross secti ons 1 and 2 were located below the confl uence of Channel A6 Lower.The increased flow in cross sections 1 and 2 compared to the other cross sections in the study site violate the steady flow assumption of the IFG-4 hydraulic s-imulation model (Bovee and Mi-Ihous 1978;Trihey 1980).Therefore,cross sections 1 and 2 were not included in the hydraulic model.Cross section 8 was located at the slough mouth immediately upstream of the confluence with Channel A6 Upper.When this channel is breached,the direction of flow in the slough mouth is altered and a large backwater eddy area occurs at the cross section. Insufficient data were available to accurately model the negative velocities which occur in the backwater eddy.Therefore,this cross section was also excluded from the IFG-4 hydraulic model leaving a total of 5 cross sections (3 through 7). A streambed profile was surveyed for the "Slough 21 Complex"that extended from the mouth of the side channel (River Mile 140.6),through the study site and SloUgh 21 to the junctures of the northwest and northeast heads of Slough 21 with the mainstem (River Mile 142.2). However,the streambed stationing was referenced to the mouth of the slough,not the mouth of the side channel.Therefore,the streambed 7-3-30 - - TOO CROSS SECTION ~ St.tion -Z+16·T50 : ;;::T., 0 ~T">II! ...I II!T4. II!:> T.20:.... 20 40 60 60 'DO '20 "0 HORIZONTAL OISTANCE If.." - "0'20'00806040 HORIZONTAL DISTANCE (f••t I 20 CROSS SECTION 6 St.ti.n -I T 84 T42 752 TO< ;;::o ~ II!...I II! II! :> 0:.... ·: "0120'DO.0 DISTANCE It••tl ,~~~~~~~~~~~~------,151 C:'1 __'T4e1. ___lOch ---5cfs 752 CROSS SECTION 3 Station -4+57.750: ;;::,..0 5 "46>II! ...I II!7'4 W:> 0:742.... 740 20 '0 .0 HORIZONTAL ".CROSS SECTION 4/0 SITE T52 CROSS SECTIDN 7 St.ti.n -3+5T St.t;on -0 t 9~ 750 ·750•:: ;;::T48 ;;::148 0!2 ;::I-74._t!i1cls C ,..C >>__14ch II!II!lOch ...I...I --II!744-\5-cfl II!TO< II!II! :>:>T42G:T42 l!:I- T40 740 !"""20 40 .0 60 '00 120 '40 20 40 00 '0 '00 ,.0 '40 HORIZONTAL OISTANCE (f.et l HORIZONTAL DISTANCE If••t I Figure 7-3-14.Cross sections for Slough 21 study site depicting water surface elevations at calibration discharges 5,10,74,and 157 cfs. !""'"', 7-3-31 stations of the cross sections at this study site are shown as negative stations and represent the distance downstream from the slough mouth. 3.3.3.2 Data Collected Calibration data were collected at the Slough 21 study site and compared to the mean daily discharge at Gold Creek Station.The calibration and discharge data is listed in Table 7-3-5. *Table 7-3-5.Calibration data collected at Slough 21 study site. Site Specific Flow Susitna River Date (cfs)Discharge (cfs) 820902 5 16,000 820919 10 24,100 830605 73 30,000 820917 157 32,000 *Controlling discharge is 24,000 cfs. 3.3.3.3 Calibration Calibration data were available at the close of the 1982 field season for slough flows of 5,10,and 157 cfs.An IFG-4 model was used to forecast depths and velocities at these calibration flows.The water surface profile associated with a slough flow of 400 cfs was also fore- cast to evaluate the model's predictive capability near the upper limit of its extrapolation range.The streambed profile,stage of zero flow, and observed and predicted water surface elevations using only 1982 data were then plotted to scale (Figure 7-3-15). The 1982 calibration data were widespread and did not provide an accu- rate description of the water surface profile at 400 cfs.Therefore,a fourth data set (73 cfs)was collected during the 1983 field season to better calibrate the IFG-4 hydraulic model.The streambed profile, stage of zero flow,and observed and predicted water surface elevations for the 1983 model are plotted to scale in Figure 7-3-16.The water surface profi 1e at 400 cfs does not appear to be correct,and the simulated profiles depart from observed values at the 5,10,and 73 cfs flows at cross sections 3,4 and 5. Because of the differences between observed and predicted water surface profi 1es,it was deci ded to separate the data sets and calibrate two IFG-4 hydraulic models;one for low flow conditions using only the 5 and 10 cfs data sets (Figure 7-3-17)and one for high flow conditions using the 10,73,and 157 cfs data sets (Figure 7-3-18)which correspond to 7··3-32 1!!IlllI.. - - - 1 1 )j ---J }]1 SLOUGH 21 74 I'I I I I I 400cfs __--------_------------------------------------ CROSS-SECTION NUMBER ADF a G SU HYDRO,1983 7 LEGEND 6 •Observed Water Surface Elevation Preliminary Simulated Water Surface Elevation ---Elevation of Zero Flow ~Cobble I Boulder 54 l>-----o.:~~<?6~~~.~....,<Poi nt of Zero Flow at -6+42 ~:~:i:Q(p'Pci~~!2'b.~..piiPo.l3'" '0 - - - --.i;lfJ~rjJ"~~;r;r.""pJt,·4.'ttflt'~ 7."0·.'.'0'8&0·''0'.'('f~4~k ··~.:·o .~~g:it:~f~~~~~····)~E\~f'R,:f~~(jq '~.".1~~;d'O~:l,fo/~?:••O":t!o·'0.~l>·9=·".'0.~'"..C:>-.••Or "l.ot,.','tJ:6:oR,<>·'o'o?o·.'~:'Y,-rf)~:oo~·0....-,':•.000.0..0:0,.,0,';,,;:·r..OoU'r "~Y'?.•.."Q "0'•'U.~.'n·~·~9~ot::Jd~t.QC{I;;·O-oJ·o\~::t..·~·O:'?6::C:.iroqi?:~o:6i~t····.'··o:4~dCfj.,o·;o~· ''")d,')n.lO .--'.::::!~_-----..-----------------.----.----------. 3 •....-------=--_-:.-.....--•IOcfs.~_........:......-----------------------------~~5cfs .-..----------.. 744 743 747 745 746 742 -.. CD CD ~-Z 0 ~ 1&1 -I 1&1 'J 1&1 I W ::J I 0::: ww .... -4+57 -3+57 -2+16 -1+84 -0+95 STREAMBED STATION (feet) Figure 7-3-15.Comparison of observed and predicted water surface profiles from non-calibrated model at Slough 21 study site. 747 SLOUGH 21 400cfs _..------------------------------------------------- 7 CROSS-SECTION NUMBER -0+95 ADF a G SU HYDRO.1985 LEGEND 65 -2+16 -1+84 •Observed Water Surface Elevat ion ----Preliminary Simulated Water Surface Elevation ---Elevation of Zero Flow fI'?:;,~'~~~J Cobble I Boulder -----------------------••• 4 -3+57 ··:·~8~:O·:ii f---Point of Zero Flow at -6+42 ~..•·~~.·~~·;~;.~\~~~;~9~.-;;'!10 -.- - - - ---- -.----- - - .".:;..~:o.~~···.QQrJ..Q:o~~··~O···.·'7:.0·'o·.,:>.......~).o.o'o,'[l50o~'8 .0.·0 ..·.0·0",,0.' •'<:>"'0'.·'""OOn~t)O~"~priCJ::·(:;i".;..o'';·O~oO.:Obc~i~";B.~-"O;"O'Q'"0":0,(j.t'I"'•.0.0·o',o.,,:-rur.J,'\i~(;.~..:.:...•..c::\'....~;,o:,·O·'()··ci'0,.:"·O··~·o·"'·•',0',.0;-,_.';o~~:o:.r:::;.·,:r,.,:r..~~~ 'b.O·O.·..~•.~({:;.·~c:::.:Q'.~:~:~q~D '.0:-~fiok3}~~·~j.~:>''-.. 'o,?O'pci ~'.'..'·~g·~.o!'.·"",rs -.i:J.Cj o'.~'!0b ~'.,QQ:b:!.qo~O:/'~'.~.~:.~8~·~~~~ooo0 .,Go·fl~::·~~~~{!:o·r· '").•·~'O·OPO '·'00 "··0<:5 .o;v...·.0;:."0"~."0 "Oli.·.g.~.o.O;~·o·...· -:>11.••g..j~b,'0.0°0 a'o::a~:J'.r''l~~o'?9'~·'0.<::;0 b:o~b:'·,r;·o:Q''~.~.:~".~~~~o '~QC.?·96()'.'~.o·.0 •0'').'6 P,.,..:.~~~..:~~;o·,o. 3 •.---------"J •IOcfs •_------------~...--~-----------------------------//I!.._---~~!.._-----------------------./ 73 cfs.--------------.--- ------ 157 cfs.-------------~-------------------~--~---------~ -4+57 741'I I .I I I 742 744 745 746 .743 -.. CD CD It-- Z 0-l- e:( > IJJ -J IJJ ......, IIII ::>w I a:w ~t- STREAMBED STATION (feet) Figure 7-3-16.Comparison of observed and predicted water surface profiles from non-calibrated model at Slough 21 study site. •)J I J -I ~]J J }J 1 )~J , 1 --1 }B :J J )]1 J }J I 1 747 746 SLOUGH 21 LEGEND •Observed Water Surface Elevation ---Simulated Water Surface Elevation ----Elevation of Zero Flow .~Cobble I Boulder ADF a G SU HYDRO.1985 -..••...-z 0-.... c:( > l&J ..J l&J -.....J l&JI W :l I 0::w ....tTl 745 744 743 742 :10.h •~~J::/-. 5 cfs Ell tra palation Range of Hydraulic Model 7 CROSS-SECTION NUMBER 6543 741 • I ,I I I -4t57 --:3+57 -2"'16 -lt84 -0"'95 STREAM.BED STATION (feet) Figure 7-3-17.Comparison of observed and predicted water surface profiles from calibrated model at Slough 21 study site for low flow regimes. 747 SLOUGH 2' Extrapolation Range of Hydraul ic Model LEGEND •Observed Water Surface Elevation --Simulated Water Surface Elevation ---Extrapolated Water Surface Elevation ----Elevation of Zero Flow ~Cobble/80ulder ADFllG SU HYDRO ,1983 ------ •e ~ ------------- 10cfs .~• 400 cfs 14 cis 151cfs C;I.' 'O.O:.~J:;;U':'..y'~Point of Zero Flow at -61"42 .·o'!~,;Q.'8·b~~'?~98?o;~~;:y.o - - - - - - - - - - - - - - - - - - - - -&o....q·.~:o.o.:Q·(j(1j).·.::;.9:-~,.:..d;\r.·"..v.'0_._ 0""CbO"o,0,00 ··~·'~ii·•.o,l(··o o(}O,'''''Q.'.,b;q~Q,.&.'()99··.'<'l(J.q.~~o,••O·"":o,.,:~.o-··.~:·P;."9/:,:0 0o~.~f£··~D:-o~~Q~QO:::1 ,.,,!:;.·oooY£...o •;.p"'.o"'·.oCJr..0'_;_:ooQQ:!~Q~'o~{I ••'Q'~~;~, I -·9~:o:;.Q"o·a~··-.<o...,·Q·o·d·~..t?-O,'Qf_,0.;'0/,\,°""0'<;1:. ;0'0'...00 .0.vO'q.~V~"86t~P.:~:~b'"..,:·:~~~j.(~~1~('·r'---------------------------..,• ~~i;J.°Ooo~d .~o.",.o·~o:O'O'i>';oi?:lQr·o..,qO.·o,v·oo'OO·oD'.'l,::''-0 .oo.oa·o ...•o("\~oo·:~oC?o~:o::·,,;.b'o .o·(r~iJ:·.a.r··.."'--1·.g.·o·.o<:lCJ~.Oo·oOO·.;D....o.Q~~·doo·~'lo·~p" '·0'o.'0 '."0::''0'"0 O'.,'...~b·~vj:o~.p~~:.b9;~;;,~,9~if~~?:~:~9r·9 ~·';.·~.·ciO.060.00'0·''·"pn.~UrF'~;···r' ••• • • 744 745 743 742 746 -Q) Q)--- z 0-.-« > l.aJ ...J l.aJ "l.aJI W ::lI 0::w O'l .- 7 CROSS-SECTION NUMBER 6543 741 •I I I I I -4+57 -3+57 -2+16 -1+84 -0+95 STREAMBED STATION (feet) Figure 7-3-18.Comparison of observed and predicted water surface profiles for calibrated model at Slough 21 study site for high flow regime. ,J l J I J l )1 1 J J !J t !.J .1 - - - mainstem discharges sufficient to breach Channel A6 Upper and the head of Slough 21. To evaluate how well the IFG-4 hydraulic models were calibrated,ob- served and predicted water surface elevations,discharges,and veloc- ity adjustment factors were compared (Appendix Tables 7-A-8 and 7-A-9). The maximum difference in water surface elevation for each calibration flow was 0.03 ft at the five cross sections.The means of the discharges predicted by the IFG-4 hydraulic models were 5,10,74,and 157 cfs which agree well with the observed values.The velocity adjustment factors for both models are within acceptable limits,ranging from 0.96 to 1.03. 3.3.2.4 Verification For Slough 21,the two-flow model (5 and 10 cfs)describing unbreached conditions has an extrapolation range from 4 to 10 cfs.Backwater effects from Channel A6 Upper below cross section 3 were observed above slough flows of 10 cfs.Therefore,the upper extrapolation limit for the two"'7flow model and the lower extrapolation limit for the three-flow model is 10 cfs.The three-flow model (10,74,and 157 cfs)describing mainstem controlled conditions in Channel A6 Upper and the head of the slough has an extrapolation range from 10 to 400 cfs.This corresponds to Susitna River discharges at Gold Creek of 24,000 to 33,400 cfs (Figure 7-3-19). A comparison was made between water surface elevations predicted by the IFG-4 hydraulic models for selected flows at the discharge cross section and the empirical rating curve developed by ADF&G (Figure 7-3-20).The slopes and intercepts of the two curves were equivalent,according to the results of analysis of covariance tests (Appendix Tables 7-A-10 and 7-A-l1). Depths predi cted by the low flow model for Slough 21 were simil i ar to the observed values (Appendix Figure 7-A-4;r=0.97).A total of 50 predicted values of a total of 251 (or 20%)were considered poor (i.e. outside cutoffs).Predicted velocities compared favorably with observed values (r=0.99),with only 6 of 251 (or 2%)considered to be poor predictions.. The high flow model also predicted depths which compared well with observed values (Appendix Figures 7-A-5;r=0.98).Fifty-four values of a total 484 (or 11%)of these values were considered poor predictions. Velocities were not as well predicted by this model,with 26 values of 484 (or 5%)considered to be poor predictions. 3.3.3.5 Application The study site in Slough 21 was chosen to represent typical spawning and rearing habitat known to be utilized by salmon (Estes and Vincent-Lang 1984:Chapter 2,Figure 2-24).The study site is located 457 ft downstream of the mouth of the slough and should be considered representative of the channel conditions between streambed station -4+57 7-3-37 4 6 8 10 20 40 60 80 100 200 400 - MAINSTEM DISCHARGE AT GOLD CREEK (xlOOOcfs) Figure 7-3-19.Relationship between extrapolation range of Slough 21 low and high flow rnedels and ADF&G flow-versus-discharge curve. 7-3-38 - - ]~-)'1 1 1 ..-I'~J )'-..~ jJ ))1 i 700 749 748 l&J-747 0"748•~~745 0::- :lZ (1)0 743- " o::ti I iii> w 742 !"'l&J w 1.0 <r..J ~l&J 741 Extrapolation range of low flow mode I ! \I Extrapolation range of high flow model !r ~ic .!_ I I • I ••..- LEGEND -Rat ing curve from observed water surface elevations and discharge measurements at ADF 8G staff gage 140.657. •Predicted water surface elevations from calibrated h~draulic models. 2 4 6 8 10 20 40 60 80 100 200 400 600 800 SLOUGH 21 DISCHARGE (cf.) Figure 7-3-20.Comparison between ADF&G rating curve and model predicted water surface elevations. and 0+00.Because of the pronounced i nfl uence of backwater effects associated with breaching flows in Channel A6 Lower,high and low flow hydraulic models were calibrated to represent the hydraulic conditions with and without backwater effects. The high flow model was based on calibration flows of 10,74,and 157 cfs and is capable of providing reliable estimates of depths and velocities for slough flows between 10 and 400 cfs.Below a 10 cfs slough flow,Channel A6 Upper is breached and backwater effects extend up into the study site.Therefore,the lower limit for the high flow model and the upper limit for the low flow model is 10 cfs.The high flow model should be applied when the mainstem discharge is in the range of 24,000 to 33,400 cfs. The low flow model was based on calibration flows of 5 and 10 cfs and is capable of providing reliable estimates of depths and velocities for slough flows between 4 and 10 cfs.This model is recommended for use when mainstem discharge is below 24,000 cfs. 3.3.4 Side Channel 10 (River Mile 133.8) 3.3.4.1 Site Description Four cross sections which define channel geometry for the 1,200 ft study reach (Plate 7-2-4,Figure 7-3-21)were surveyed in 1983.A fifth cross section (cross section 4)was later synthesized and included in the study site to better define hydraulic conditions in the upper third of the side channel.Cross sections 1,3,and 5 describe pool areas,cross sections 2 and 4 riffle areas. 3.3.4.2 Data Collected Provisional USGS streamflow data for Gold Creek were used to determine the mean daily discharge on the dates that calibration data were collected at the Side Channel 10 study site (Table 7-3-6). *Table 7-3-6.Calibration data collected at Side Channel 10 study site. ..- Site Specific Susitna River ~ Date Flow (cfs)Discharge (cfs) ~ 830726 8 19,400 830724 78 22,700 830810 785 31,900 -, *Controlling discharge is 19,000 cfs. 7-3-40 ,- - ...-+--r-..,...-.,......,.........r-"""Ir-"....,-..,........, / •••... ..662:... z 2- i ~ III III:>• II: ...... 8.. CROSS SECTION 3 Statioft t 8 of 51 .._-~~~~;r:=-=--eOeh--leh o ~~~~~I~I~110 I~ HORIZONTAL DISTANCE U ••t1 ....CROSS SECTION I ....Slatioft 11 +25 644-r,.........'l"-_~....,....'l"-~ 140 160 tao HORIZONTAL DISTANCE 1f.1) 66.CROSS SECTION 4 .14 Sialioft 20 +85-•••• =...0 z •••2...8'"oC>•••III ..J III .,. III 8eo::::> II:............ o .'0 '0 .0 80 100 "0 "'\;;;;;;::::::::::===~7""'==;;;;;;;;=:;==':I'_-_-8~~:: 20 40 eo 110 100 120 I.e ISO 180 HORIZONTAL DISTANCE I f ••I) -662 •.:660 zo S>III... III ...650:> II: ...648... ••.;-...,.--r-..,.."""'..,...-.,......,......,...~r-"~ 20 40 80 eo 100 120 140 ISO leO HORIZONTAL DISTANCE I h.l) CROSS SECTlON 5/Q SiTE Station 23 +21 o ••• ••• ... -..662 :'660 z u.0 ~ oC>~•lac'"lets III .... III:>.1lO'II:....45 CROSS SECTION 2 Staliaft 13 +65 .......-....•=.60 Z .,. 2...•••oC>.,. III....,.III III '.0:> II:...... •••... 0 20 ..0 60 eo 100 120 140 160 110 HORIZONTAL DISTANCE (f••t) Figure 7-3-21.Cross sections for Side Channel 10 study site depicting water surface elevations at calibration discharges of 8 and 80 cfs. 3.3.4.3 Calibration Calibration data were collected at side channel flows of 8,78,and 785 cfs during 1983.The water surface profile at a 1,500 cfs flow was forecasted to evaluate the predictive capability of the model at the upper limit of its extrapolation range. The streambed profile,stage of zero flow,and observed and predicted water surface elevations for the study reach are plotted to scale in Figure 7-3-22.The available data were widespread and did not provide a re 1i ab 1e forecast of hydrau 1ic condi ti ons over the flow range bei ng simulated.This was largely due to mainstem flow spilling over the gravel bar and entering the study site between cross sections 1 and 2 and 2 and 3 at the time the 785 cfs data set was obtained.Thus,the 785 cfs data set was not used in further refinement of the hydraul ic model. A two-flow IFG-4 model was calibrated using the 8 and 78 cfs data sets and a 100 cfs flow was selected as the upper limit of extrapolation.A fifth cross section was added to the original four at streambed station 18+57 using the streambed elevation and stage of zero flow from the surveyed streambed profile.The cross sectional shape was derived from aerial photography and by extrapolating between the cross sections at streambed stations 13+65 and 20+85.The IFG-4 model was calibrated and the resulting water surface profiles are plotted to scale in Figure 7-3-23. To evaluate the performance of the IFG-4 hydraulic model for Side Channel 10,observed and predicted water surface elevations,discharges, and velocity adjustment factors were compared (Appendix Table 7-A-12). There was no difference in observed and predicted water surface elevations for both calibration flows at the five cross sections. Limited significance should be applied to the results because the data points are at the end of a two-point rating curve.Mean calibration discharges predicted by the two-point IFG-4 hydraulic model were 8 and 80 cfs,respectively.The velocity adjustment factors range from 0.87 to 1.01,which indicates that the models are suitably calibrated. 3.3.4.4 Verification For the Side Channel 10 hydraulic model,the recommended extrapolation range is from 5 to 100 cfs.Side channel flow of 6 to 100 cfs corre- spond to Susitna River discharge at Gold Creek from 19,000 to 24,900 cfs (Figure 7-3-24).Below 19,000 cfs,side channel flows are generally less than 5 cfs because the upstream berm is not overtopped. A comparison was made between water surface elevations predicted by the IFG-4 hydraulic model for selected flows at the discharge cross section and the empirical rating curve developed by ADF&G for cross section 5 (Figure 7-3-25).The analysis of covariance results indicated that intercepts and slopes of these two curves were equivalent (Appendix Tables 7-A-13 and 7-A-14). 7-3-42 ~- - - ,~. til OJ OJ>, U "0 <tl::l4-+-' lO-til ::l til 0 .--i lO- OJ.- +-'OJ <tl e 3:e <tl "0 ..s:::. OJu +-' U OJ ....."0 "0 ..... OJ(/) lO- C.+-' <tl "0e.- <tl OJ "0 "00 OJE > lO-"O OJ OJtil+-' -OltlolO- -04-..... 0.- ItleUor tile .....0 lO-e <tl C.E EO OlO- U 4- ..... 4-OJ O+-'lO-..... C.til ...-ltl +-•~•... z 0 t-ee t-en Q..... a:I :::Ece..... a:: t-cn N + rtl N ltl lD +N ~N I M Ir--- OJ lO- ::len..... L.1... ltl N += a> ~ II) zo ~ac: 11I11I WID '::IiW::I ~z ac: u N ", '".. oon II) ~o .. on II) Nonco'"on II) on on II) II)on II) .... on <D -\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ I \ \ \ \ \ 'I \ \ \ \ \ \, \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ ~\ \ I \, I..\ ~\ "'I~\ I, I• ~ dzz« I U Wo (J) II) on <D \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \, \ \ \ 1 1 1 I I I I ..I -I U I0, ~I -I 1 1 I I 1'§liilfIl'. 7-3-43 +- lD lD.... ~ Z 0-I-«> I&J '-J ..I I I&JW I+::>I&J +::>~ 0:: I- 656 61111 U4 6153 6112 6111 - UO SIDE CHANNEL 10 ~o~~.--;::::; ~O~'· ....--;;. ~' ~ !T 83 ~ ~ .---;:. .--;:.. ~ LEGEND •Observld WQI8r Surface Elevation --Simulated Waitr Surface Elevation ----Elevotion ot Zero flow c=J Silt I Sond c::3Gravell Rubble tE;,:;;3Cabble I Boulder ADF"G SU HYURO ,1983 1 I I649'I I 11+25 2 13+65 3 18 +51 STREAMBED STATION (teet) 4 20+85 5 CROSS-SECTION NUMBER 23+21 Figure 7-3-23.Comparison of observed and predicted water surface profiles from calibrated model at Side Channel 10 study site. I 1 I J J J 1 ~l I I !~I J J F"'" I 1000 900 800 700 600 500 400 300 200 -U)100....90U80-70 3=60 0 ~O ...Ju..40 0 30 ...J LLJ 20 Z Z« ~ 0 10 9 LLJ 8 0 7-6 (J) 5 4 3 2 L:.EGEND •Coincident mainstem discharge and side channel flows at whIch calibration data were-collected. ADF8G Flow Versus Discharge Curve for Side Channel 10 '-...... QSC=10-35.5566 (QMSJ 8.5446 ~ Recommended Extra- polation Range of the Hydraul ic Models under Mainstem Con- trolled Discharges. (19,000,10 ) ~ S ide channel flow determ i ned by local runoff ond upwelling for mainstem discharge below a breach- ing discharge of 191 000 ch. I 2 4 6 8 10 20 40 60 80 100 ,... i MAINSTEM DISCHARGE AT GOLD CREEK (x IOOOcfs) Figure 7-3-24.Relationship between extrapolation range of Side Channel 10 model and ADF&G flow- versus-discharge curve. 7-3-45 .\! :Extrapolation range for model l I~·i ~ I •*-....- 400 600 800 11000200 LEGEND .-Rating curve from observed water surface 8.18vations and disch9rQe measurements at ADF8G staff gage 133.8$3. •Predicted water surface elevations from calibrated hydraulic model. 40 60 80 100206 8 1042 -<t- CD .!664-Z 662 0 660 li 658 >"I&J ..J I&J I&J 0 -....,J if I W 0:: I ::l~652 Q)(f) 0:: I&J ~651~ SIDE CHANNEL 10 DISCHARGE (cfa) Figure 7-3-25.Comparison between ADF&G rating curve and model predicted water surface elevations. I )1 J !I l .,I I I .-.'._.I 1 I J !~ .... .... A total of 33 of 343 (or 10%)of the predicted depths from the side channel 10 model were considered to be poor predictions (Appendix Figure 7-A-6).Predicted velocities were somewhat poorer (r=0.98),with 59 of 343 (or 17%)of the values outside the cutoff limits . 3.3.4.5 Application The study site in Si de Channel 10 was chosen to represent possi b1e spawni ng and reari ng habi tat in the free-fl owi ng porti on of the side channel from streambed station 5+00 to 23+00 (Estes and Vincent-Lang 1984:Chapter 2,Figure 2-4).In effect,the study site includes the entire free-flowing portion of the side channel and is suitable for forecasting hydraulic conditions for both breached and non-breached conditions.The model is based upon calibration flows of 8 and 80 cfs. It is capable of providing reliable estimates of depths and velocities for side channel flows between and 6 and 100 cfs which correspond to a range of mainstem discharge from 19,000 to 24,900 cfs.However,field observations and supporting data indicate that the gravel bar which separates the side channel from the mainstem is overtopped in two locations at mainstem discharges greater than 30,000 cfs.Consequently, the model is not applicable for this range of mainstem discharges. Caution should be exercised when applying the model to mainstem flows between 25,000 and 30,000 cfs. Field observations indicate that side channel flow is typically in the range of 3 to 5 cfs when the mainstem discharge is less than 19,000 cfs and not 1arge enough to breach the head of the side channel.Hence, another undefined area exists at this end of the calibration range. 3.3.5 Lower Side Channel 11 (River Mile 134.6) 3.3.5.1 Site Description The multiple cross section study site at Lower Side Channel 11 was established in June 1983 (Plate 7-2-5).The IFG-2 hydraulic model was selected for use of this site rather than the IFG-4 model because of the size of the channel,the uniform nature of hydraul ic conditions at mainstem discharges of 9,000 to 30,000 cfs and its cost-effectiveness (only one data set was needed for model calibration).Five cross sections were surveyed to describe the 1,416 ft study reach (Figure 7-3-26).A sixth cross section at streambed station 3+34 was generated by interpolation.Cross sections 2,3,4,5,and 6 describe a long run upstream from the hydraulic control which is delimited by cross section 1. 3.3.5.2 Data Collected On the dates that calibration data were collected at the Lower Side Channel 11 study site,mean daily discharge were determined for the Susitna River at Gold Creek.A site specific flow of 820 cfs with a corresponding Susitna River discharge of 9,400 cfs was collected and September 29,1983. 7-3-47 LOWER SIDE CHANNEL II ~~g;::~~~.~~E;l~ON _S#llI%A- $oR'"IU ...CROSS SECTION I .1.CROSS SECTION 4 Station 0 +00 Station 9 ....53.'"..10..::!•••••• Z Z 00666·~...~~C>III ...III ...oJ _!20cfloJIII III III III 662 :::>... :::>'"0:.. .1-..0 ••0 ~•6..6• .0 .0 ,.0 ,.0 .00 "0 '.0 >20 ••0 40 .0 120 ,.0 .00 >40 ••0 320 "0 HORIZONTAL DISTANCE (feet I HORIZONTAL DISTANCE'(l.otl .~ .1'CROSS SECTION 2 .72 CROSS SECTION S'ation 3....34 Station 11+98 6?'O 010;:.-:6se ••• Z Z 0 0 •••j:...~ C C>> III ...III ••4............••2 ..•••=>:::> 0:'"I-.60 I-'.0 .6..6' '0 '0 120 '.0 200 '40 '.0 ='60 40 .0 120 ,.0 200 "0 '.0 320 >60 HORIZONTAL DISTANCE (f••tl HORIZONTAL DISTANCE {f..11 ~ .12 CROSS SECTION 3 10 SiTE .1.CROSS SECTIO N 6 Stat ian 6+68 Station .41'16 '10 '10.... = M'!-'l,~•••••• z z 2 ...2 •••I-l-CC>_E'l20cr..>•••..........oJ ..-......,....2 =>:::>'""'l-••0I-••0 5~e .6. .0 '0 120 "0 200 240 '.0 >20 >00 40 .0 120 "0 200 240 2.0 320 '.0 HORIZONTAL DISTANCE II..tI HORIZONTAL DISTANCE ( l ••t I study at Figure 7-3-26.Cross sections for Lower Side Channel 11 site depicting water surface elevations calibration discharge of 820 cfs. 7-3-48 - ,.... I 3.3.5.3 Calibration A large gravel bar originates at the left bank facing upstream near .cross section 4 and extends diagonally 1,100 ft downstream.At discharges below 16,000 cfs,the gravel bar parallels the direction of flow and extends from cross section 1 upstream through cross section 3. The gravel bar divides the flow into two parallel streams between cross sections 1 and 3,and caused differences of 0.56 ft and 0.85 ft in right and left bank water surface elevations at each cross section, respectively (Figure 7-3-27).Since the IFG-2 model required a horizontal water surface elevation at each cross section,the differences in left and right channel water surface elevations had to be adjusted.The largest portion of flow occurred to the right of the gravel bar.Therefore,the water surface elevations for the right channel (looking upstream)were used as the representative elevation for the entire cross section.However,the depth of flow in the left channel had to be maintained.The mean difference between the right and left channel water surface elevation at a cross section were added to the surveyed streambed coordi nates for the 1eft channel.Thi s raised the streambed elevations for the left channel at the cross section so the measured depths in the left channel at the calibration flow would not change but a horizontal water surface was provided at the cross section.This procedure was repeated for cross sections two and three. The di stance between cross secti ons 1 and 3 appeared too 1arge to adequately define the flow conditions between these sections.A sixth cross section was added at streambed station 3+34.A linear transition in channel geometry was assumed to occur between cross sections 1 and 3 since the instream hydraulic conditions appeared constant.The slope of - the streambed was assumed to be approximately the same as that of water surface profile between cross sections 1 and 3. A rating curve was developed for a staff gage located at cross section 3 and then used to determine the water surface elevations at cross section 1 to forecast a range of flows.The velocity values were assigned by constructing isopleths between cross sections 1 and 3.Water surface profile and depth-velocity data collected at cross sections 1,3,and 6 were used as the basis for calibrating an IFG-2 model.The Manning's n values were adjusted for each cross segment using a modified version of Manning's equation for the study site: C R 2{3 n = v 7-3-49 11_.- 160 200 240 280 320 :360120.040 .12 CROSS SECTION I SI.tiD.0 +00-.10..:••• z 0 •••j:::: c>...III ~ III III ••2 :::> '"l-••0 ••• 160 2.otJ 240 280 320 360120.040 ."CROSS SECTION I S latlan °tOO 670•.: 668z 0 j::::•••~ III ~.... III III 56':::> II:~ ••0 .0. HORIZONTAL DISTANCE (f..l1 HORIZONTAL DISTANCE (f••t l 160 200 240 280 320 ~60'20 HORIZONTAL OISTANCE (to.II .040 .n CROSS SECTION "3 f 0 SITE Stat Ion 6t-68 .10 ••••• Z 0 •••j:::: C>•••III ~ III III ••2 :::> '"l-••0 6~e .72 CROSS SECTION :5 I Q STTE Slatian 6t68 .10..:... z 0 50'j:::: ~.o.III ~ III III 66~ :::> II: ~.60 .0. 40 .0 120 1110 200 240 2eo 320 ••0 HORIZONTAL OISTANCE (f••t) "... Figure 7-3-27.Comparison between measured and adjusted cross sections 1 and 3 for Lower Side Channel 11 study site. '"'"I 7-3-50 .... .... where: n =roughness coefficient for the cell C =1.49 x (the slope of the energy line between adjacent cross sections)1/2 R =hydraulic radii,ft V =mean cell velocity,ft/sec For a given flow,the slope of the energy line remains constant between adjacent cross sections.The Un"value for each segment of the cross section was adjusted until the predicted water surface elevation and the velocity distribution across the channel agreed with those observed at 820 cfs.Cell velocities were adjusted in a similar manner at those cross secti ons for whi ch detailed depth and velocity data were not available until the water surface elevations agreed with the predicted value at 820 cfs and the "nil values were similar to those for the adjacent upstream and downstream cross sections.The final water surface profile was plotted to scale (Figure 7-3-28). 3.3.5.4 Verification The hydraulic model for Lower Side Channel 11 has an extrapolation range from 400 to 2,000 cfs.This corresponds to Susitna River discharges at Gold Creek of 5,900 to 16,700 cfs (Figure 7-3-29). A comparison was made between water surface elevations predicted by the IFG-2 hydraulic models for selected flows at the ADF&G discharge cross section and the empirical rating curve developed from ADF&G data (Figure 7-3-30).Because only one calibration flow was used to calibrate the Lower Side Channel 11 model,a statistical analysis could not be made. Data points predicted by the model were plotted against the rating curve and appeared to be within the acceptable limits for habitat modelling. Depths and vel oci ti es input into the I FG-2 computer program do not necessarily have a one-to-one correspondence with measured depths and ve 1ociti es in terms of cross-secti on verti ca 1s (see Mil hous et a1• 1981).Accordingly,the comparison of observed versus predicted depths and velocities was not made for Lower Side Channel 11. 3.3.5.5 Application The study site in Lower Side Channel 11 was chosen to represent poten- tial spawning and rearing habitat in that portion of the side channel 7-3-51 666 LOWER 51 DE CHANNEL II - ----------- J= Extrapolation Ra.ge al HydrlJulic Ma~el------------ ------- LEGEND •Ob ••rvld Wat.r Surface Elevation -_.Simulat.d Wall'Su,la.,E'..aUa. ---E,t,apalatia.Wale,Su,la••EI ••aUa• ~Gra••I/Rubbl'~p,•••u "YORo,l.n -------------- ---- ---- --------~l?.0~----- -------- ..:~.',~,~-.._''-i~",0-• ~OOO 0"---------~- - 6611 664..••-~ z 6e1 0-... <C>662 1&1 ..J 1&1 -...,J 1&1 " (.oJ ;)661 I II:: U1 ... N 660 6B1t I I I I606'I I 2 :s 4 o 6 CROSS-SECTION NUMBER 0+00 :S+14 6+66 9+0:S 11+96 14+16 STREAMBED STATION (fUt) Figure 7-3-28.Comparison of observed and predicted water surface profiles from calibrated model at Lower Side Channel 11 study site. 1 J ~.~"I J ))J J I .~I i 1 I , ..... LEGEND •Coincident mainstem discharge and side channel f low at which calibrat.ion data were collected. Recommended Extra- polation Range of the '....__Hydraulic Models under Mainstem Con- trolled Discharges. ADF aG Flow Versus Discharge Curve for Lower Side Channel II QSC=I0·3.2278 (QMSI'OS4\ 1.000 900 ,. 800 700 600 500 2.000 300 5.000 4.000 10.000 .9.000 8.000 7.000 6.000 -J LIJ Z Z« J: (.) ILlo-en 0:: ILl 3=o -J ~o ..J IL -.,...o- - - 200 S ide channel flow determ i ned by .local runoff and upwelling for / main.tem discharge below a breach- ing discharg.of ~.900 eta. 100,_......_.....~.....,.__.....__.,......_...IIIIIIpII...,....., ....4 6 8 10 20 30 40 50 60 708090100 M AINST EM DISCHARGE AT GOLD CREEK (x IOOOcfs) Figure 7-3-29.Relationship between extrapolation range of Lower Side Channel 11 model and ADF&G flow- versus-discharge curve. 7-3-53 ----------------~---------~------- 661 ,iii iii ii',,I • I •II II I 670 669 668 687 666 ......... I <'0 I 01..p,. -..••....-zo ~>I&J .J IIJ I&Jo<t lL 0::: j tn 0::: IIJ ~ ~ 665 664 663 662 LEGEND -Rat ing curve from observed water surface e levat ions and discharge measurements at ADFaG staff gage 134.652. ..Predicted water surface elevations from calibrated hyd raulic mode I. r- 100 200 400 600 800 IPOO 2POO 4,000 6,000 8,000 10,000 LOWER SIDE CHANNEL II DISCHARGE (efa) Figure 7-3-30.Comparison between ADF&G rating curve and model predicted water surface elevations. ~J I ~)1 I I I 1 t I E .t I J •J ~ -which extends from cross section 1 upstream to the mouth of Slough 11;a distance of 1.1 miles.The model is based upon a calibration flow of 820 cfs and is capable.of providing rel iable estimates of depths ~nd velocities for side channel flows between 400 and 2,000 cfs.TT\is corresponds to mainstem discharge at Gold Creek ranging from 5,900 to 16,700 cfs. To extrapolate beyond this range,small changes in the roughness coeffi- cients can be made.Manning's n values could be adjusted in the model until the forecasted water surface elevations fit the water surface elevation-versus-discharge curve for the study site.Application of this procedure would give a reasonable app~oximation of depths and velocities within the study reach when mainstem discharges at Gold Creek were greater than 16,700. 3.3.6 Upper Side Channel 11 (River Mile 136.0) 3.3.6.1 Site Description The study site at Upper Side Channel 11 was established in June 1983 to obtain field data necessary to calibrate an IFG-4 hydraulic simulation model (Plate 7-2-6).Four cross sections were located to define channel geometry for the 1,040 ft study reach (Figure 7-3-31).Cross sections 1 and 2 describe the upper extent of the backwater zone;cross section 3 the transiti on area between the backwater zone and along ri ffl e;and cross section 4 the riffle. 3.3.6.2 Data Collected Mean daily discharge at Gold Creek on the dates calibration data were collected at the Upper Side Channel 11 study site were determined from provisional USGS streamflow data (Table 7-3-7). Table 7-3-7.Calibration data collected at Upper Side Channel 11 study site.* Date 830914 830712 830608 .Site Specific Flow (cfs) 2 54 107 Susitna River Discharge (cfs) 10,700 19,700 22,000 *Controlling discharge is 16,000 cfs. 7-3-55 ...,. -UPPER SIDE CHA....EL II !o-tAO..-aG CROSS SECTION '.. ,0.~::O SnF~......"""'-....~....._-..........=="""''I'r.f" .."..---SUS,rN", 6.0 CROSS SECTION I 6 ••Station 0+00. 6.'.; Z 6•• 0;::6.'...:>6.0... ..J...6'....".:::> 0:....74.,., .90 CROSS SECTION •••Station 4 +30·=... z ,.. 0;::•••~'.0... ..J =I~~~~:...,,, --1Z~1s...676:::> 0: i-a,. .,., ..... :'0 40 <50 eo lOO 120 HORIZONTAL DiSTANCE (loon IElO 200 ZC 40 60 80 100 12.0 140 160 IEle 2.00 HORIZONTAL DISTANCE 11001) 690 CROSS SECTION '"'Statton 2+00 !.86 Z 0;::,.,... :>..._1I0ch..J....,.-54eh -12eh...67.:::> 0:... ,n 2.0 40 60 80 100 1:2.0 140 160 180 200 ••0,,,··... z .,. 0 i=682 ~,.... ..J...678...".::> 0:...a,. 67' 0 CROSS SECTION 410 SITE Station 101'40 20 40 SO ElQ 100 120 140 160 I eo 200 HORIZONTAL DISTANCE (fool)HORIZONTAL DISTANCE (loolJ Figure 7-3-31.Cross sections for Upper Side Channe1 11 study site depicting water surface profiles at calibration discharge of 12,54,and 110 cfs. 7--3-56 ,~ 3.3.6.3 Calibration Three sets of fi e1 d data were co 11 ected at the study site for side channel flows of 2,54,and 107 cfs.These data were used to calibrate an IFG-4 model.Water surface elevations corresponding to the three calibration flows were forecast as well as the water surface profile for a side channel flow of 250 cfs.This flow was selected to evaluate the predictive capability of the model at the upper 1imit of the recommended extrapolation range for a three-flow IFG-4 model.The·streambed profil e,stage of zero flow,and observed and predi cted water surface elevations are plotted to scale in Figure 7-3-32.Differences between the observed and predicted water surface elevations at 2 cfswere as 1arge as 0.07 ft,and the predi cted water surface profi 1e for 250 ·cfs was not considered reliable.The field data were re-examined and it was determined that the 2 cfs data set was obtained at a side channel flow too small to be reliably used in the hydraulic model.Therefore,this data set was deleted and the model calibrated using only the 54 and 107 cfs data sets.Water surface profiles for flows of 10 and 250 cfs were forecast and plotted to scale.The predicted depths and velocities at 10 cfs were compared to the measured values in the 2 cfs data set. Velocity distribution patterns were similar to observed values and depths,as expected,were slightly greater than observed.Thus,the depths and velocities for a flow of 10 cfs was accepted as being a more reasonable estimate of hydraulic conditions near the low end of the cal ibrati on range for the model than the 2 cfs data set.The 10 cfs flow was therefore used as a synthesized calibration data set.In this manner sufficient data were obtained to calibrate a three-flow IFG-4 model for the study site.The water s~rface profiles forecast by the model are provided as Figure 7-3-33. To evaluate the reliability of the IFG-4 hydraulic model calibrated for .Upper Side Channel 11,observed and predicted water surface elevations, discharges,and velocity adjustment factors were reviewed (Appendix Table 7-A-15).The maximum difference in water surface elevations for each calibration flow was 0.01 ft at the four cross sections.Means of the di scharges predi cted by the model were 12,54 and 110 cfs,in comparison with input values of 10,54,and 107 cfs.The velocity adjustment factors for the model were in the range from 0.96 to 1.06. 3.3.6.4 Verification For Upper Side Channel 11,the three-flow hydraulic model (12,54 and 110 cfs),has an extrapo 1ati on range from 5 to 250 cfs.The channel breaches at a mainstem discharge of 16,000 cfs.The model is calibrated for Susitna River discharges ranging from 16,000 to 25,200 cfs,which corresponds to a side channel flow of 25 to 250 cfs (Figure 7-3-34). Side channel flow under unbreached conditions ranges from 5 to 25 cfs. A comparison was made between water surface elevations predicted by the IFG-4 hydraulic model for selected flows at'the discharge cross section and the rating curve developed by ADF&G (Figure 7-3-35).Both curves had equivalent slopes and intercepts as evaluated by analysis of covariance (Appendix Tables 7-A-16 and 7-A-17). 7-3-57 .... - "0 V>(lJ >-.!'-c..(lJ c.. "0 c.. s:::=:l to +-> "0 to(lJ >r- >-'(lJ (lJ"o III 0 .oEo "0 ~(lJ 0+-3 to s:::!'- 0.0 1Il'r- til(lJ .,.--or- .,... I..L. .,...ill ~+-> 0'""!'-til c.. >, (lJ"o U::l to+-> ~1Il !'- ::l..--l tIl..--l >-'r-(lJ(lJ +->s::: tOS::: 3tO J:: "0 U(lJ +->(lJ U"O .,...r- !'-to tOU c..I E s::: 00 us::: oo+ (\I oo+o 10.... ID z 2 ~acu..., ~ID I ::I..0::/ '"II :gZ .2 !!II:;;..U 0>a:~Q .. r.I ,...+G '""''':::>0 =-=en ~..,.<II>IJI II ..._.. Q r.I:!.. GO C ":t :a z ~"Cf 0..G- ILl ,.-1&- <.!)cn~0,.....ILl ie lD G -I _·-N ~<fIJI ,. 3:>0.0 .. .,,:;c:~1:D .c::oo ......:='S:::cn u ::;:~~~..-.-0 OCoUJIJIU:,ni•I I U?: I .---CD CD-- Z 0 ~ oct ~ (/) Q 0 ~ If)Q1 If)+~ oct..~a: ~en ........ ID CD.... ID o CD ID -J W Z Z« J: U W Cl en 0:: I.LJ Q.. Q.. ::::> \\'\.\~~~~~. \ \ \\..:9i;~. \\ \\\12;g.:~t.·~...\ \ \go:;?~:\ \ \ \'~.~.~c:>. \""\'.(j:~~. '\\\\~,~. \ \ \ \'1£;;@fc\ \ \ \.'o.~':l,. "\ \ \·:';6~\«\\\~~~~ \ \ \ \ ..'/0"0•."\ \ \ \.~~~~'Y.;f- \ \'q,;ei··\~\\\\\'O{~i-~~~ \ \ \ ,;;~b'=& \\\,\\·.t~~ \\\\ \\\, \\\\ \\ \ \ \\,\ \ \•·'1 \•r I I l I \ : I l \ I I I \ I I I , : I I \ , I I \ r I I \ J 1 I \ !I I \ , I 1 \ J I 1 \ I 1 I : I 1 \:•+\ 1 I 1 1 I I I 1 1 ,I I ~1 I ~: "";;it .:!~I '(;.~\;:;:CIl I NI 0 ~I ~ \I I ,I I ,I I \I I I ••I. (I 88!)NO I J.'11"3,3 .3 n ij J...,.., .." 7-3-58 1 1 }1 1 1 i 1 1 Extrapolation Range of H yd raulle Model CROSS-SECTION NUM-.ER4 10+40 ADFIlG/SU HY·DRO ,11183 LEG EN 0 •Observed Water Surface Elevation --Simulated Water Surface Elevation ---Extrapolated Water Surface Elevation ---Elevation of Zero Flow c=J Silt /Sand ~Cobble /Boulder .... /"... 3 4+-30 ---~ 2 2+00 //} .../ .-/ ////'.../,,:"";..O~Q·~ ,/'........~·{hoWt' ........:.!J":o~6'·.o'!;" oQ _.~~oD:O~D.:·:~""·{)·'{g(j-o:o,,orJJ·.,~·o~.J", .'0.':t'~ti~~~;F~·'r .••no<.o~.poo,)P.oQrdbglFi~~J~~f~~::,·;<or"' ",I''''.'O",·,·o",-·~.iio.:-u?'_2.i~:::(P.-O·~~t;.:o·o"f'· "'iJo..u.Q(jJ0"0'0.. 0 .,.oo.~o~:o~~;:Q~:o.•f} [\..:..o_cd~~o.o}.'t' 54cfs 250 cfs 110 cfs -------------~ UPPER SIDE CHANNEL II 0+0.0 677 681 680 679 675 678 676 ___Je.!!------- Point of Fio-;;::j i h·····..~Po....···,;..0-nr.:~~r.;; 674 I I I I I +- Gl /II.... ~ z 0-I- <t.> .......,W I ...J W W t U1 1.0 W :J a:: I- STREA MBED STATION (feet) Figure 7-3-33.Comparison of observed and predicted water surface profiles from calibrated mOdel at Upper Side Channel 11 study site. (25,200,250 ) Recommended Extra- potation Range of the ____Hydraulic Models under Mainstem Con- trolled Discho rges. LEGEND •Coincident mainshm discharge and side channel f lows at which calibration data were collected. (16,000,25) ADF 6:G Flow Versus Discharge Curve for Upper S ide Channel II Qsc =10~19.9340(QMS)5.0729 ~ so 40 30 zoo 400 soo 300 100 90 80 70 60 1000 900 800 700 600 -- ...J UJ Z Z« :I: () UJ C-en a: UJa.a. ::> 3=o .J LL -., tI- U- 20 Side channel flow determined by local runoff and upwell- ing for mainstem discharQe below a breach ino discharQe at 16,OOOch .. 10 -.._..,......_...-.,..."....op-__....._..,._op-............,...,.... 6 8 10 2 4 6 8 10 MAINSTEM DISCHARGE AT GOLD CREEK (xIOOOcfs) Figure 7-3-34.Relationship between extrapolation range of Upper Side Channel 11 model and ADF&G flow- versus-discharge curve. 7-3-60 1 1 1 J ])1 1 .-J -)J ] • LEGEND -Rating curve from observed water surface elevations and discharg.measur.ments at ADF8G stoff gage 136.251. •Pr.dict.d water surface elevations from calibrat.d hydraulic mod.I s. '"....' I I ,I I....Extrapolation range of mode I ~I I r • 690 689 688-687-e 686e'685....-684 Z 681 0 682~681> l&J 680..J l&J 678 l&J 0«678 lL 0::-...,J ::lI (/)w 677I 0'\ 0::I-' l&J...« ~ 676 -l j iii iii iii iii iii iii iii i i 4 6 8 10 20 40 60 80 100 200 400 600 800 ~OOO UPPER SIDE CHANNEL II DISCHARGE (cfe) Figure 7-3-35.Comparison between ADF&G rating curve and model predicted water surface elevations. Depths were predicted with a high degree of accuracy by the Upper Side Channel 11 model (Appendix Figure 7-A-7;r=0.99).Only 27 of a total of 414 (or 7%)predicted depths were considered poor.The velocities were also quite accurately predicted (r=O.99),with only 15 of 414 (or 4%) predicted values considered poor. 3.3.6.5 Application The study site in Side Channel 11 was chosen to represent a known chum salmon spawning area and possible salmon rearing habitat in the free-flowing portion of the side channel from streambed station 4+30 to 22+32 (Estes and Vincent-Lang 1984:Chapter 2,Figure 2-6).The model is based upon calibration flows of 12,54 and 110 cfs and is suitable for forecasting hydraulic conditions for both breached and non-breached conditions.It has been ca1"ibrated to reliably forecast depths and velocities associated with side flows between 5 and 250 cfs.This corresponds to mainstem discharge up to 25,200 cfs.Field observations indicate that side channel flow is approximately 2 cfs when the mainstem discharge is not large enough to control the side channel (less than 16,000 cfs).Duri ng side channe 1 flows,when the channel is fi rs t breached,a backwater area caused by the mainstem exists in the lower portion of the study site.Therefore,data from cross sections 1 and 2 should not be applied to any other segments in the side channel.Data from cross sections 3 and 4 can be applied to the free-flowing portion of the side channel from streambed station 4+30 to 22+32. 3.3.7 Side Channel 21 (River Mile 141.2) 3.3.7.1 Site Description A multiple cross section study site was established in the Side Channel 21 study reach in June 1983 (Plate 7-2-7).Five cross sections define the channel geometry for this 886 ft study reach (Figure 7-3-36).As explained in the description of the Slough 21 study site,the streambed stati ani ng for the Slough 21 Complex is referenced to the mouth of Slough 21.Therefore, the station of each cross section in the study reach represents its distance downstream from the mouth of Slough 21 and is reported as a negative value.Cross sections 1 and 5 describe pool areas.Cross secti ons 2 and 4 are located in the transiti all areas between the pools and the riffle that is defined by cross section 3. 3.3.7.2 Data Collected Mean daily discharge for the Susitna River on the dates that calibration data were collected at the Side Channel 21 study site were determined from provisional USGS streamflow data (Table 7-3-8). 7-3-62 - - """', ,.... SIDE CHANNEL 21 t---4A'DF aD CROSS SEcnON 6 ADF a;STAFF GAGE /702 CROSS SECTION 3-S'olion -35 +74 •748• Z 744 0 l-e 740>~;~~~::'"..l 73.'"IOOch........2.3ch III ::::l 73.II: I- 72. 30 60 90 120 150 teo :::IQ 240 270 '300 330 360 HORIZONTAL.DISTANCE (fnt) 732 752 •748 ~ CROSS SECTION Stolion -38+92 '---"'-"""1;'::======7 --776 c1 s--43Ich """-'_==~=====I ~~~:: 752-!148 z:2 744 l-e>140 III ..l III '"::::l II: I- CROSS SECTION 41 a SITE Stolion ·33 +42 728 -fpo.."I""P"...,...,..,"""',.,..P"""I"l"'~ 30 60 90 120 150 leo ,10 2.40 ,70 300 330 360 HORIZONTAL.DISTANCE (fnl) 7281-..r"""..,._.,......,......,.....1""'..,......,...""I"_.,......,...~ o 30 60 90 1'2.0 150 180 2.10 240 2.10 300 330 360 HORIZONTAL.DISTANCE (fnt) 72.+....'I"'I"'..,.......,......,....."T"""""'...,.,.."""''''''''I''l'''...,~.,..'"''''' CROSS SECTION 2 Station -37 +07 ..748 ~ Z 744 !:! I- ~740 III ..l 11,I ns III ::::l II:732 I- -""t;~~~~~~~~~_~~~~~.776-efs.----43Icfs IOOch 23eh 752 CROSS SECTION 5-Station·30 +06•1 ••:. z 744!:! l-e 740> III ..l III 73. III ::::l II:732I- 728 - 30 60 90 120 150 lao Z10 240 210 ~oo 330 3EiO HOR IZONTAL.DISTANCE (feet) 30 60 90 120 150 180 210 240 270 300 330 360 HORIZONTAL.DISTANCE (feet) Figure 7-3-36.Cross sections for Side Channel 21 study site depicting water surface profiles at calibration discharges of 23,100,431 and 776 cfs. 7-3-63 Table 7-3-8.Calibrition data collected at Side Channel 21 study site. *Controlling discharge is 12,000 cfs. 3.3.7.3 Calibration Calibration data were collected at side channel flows of 23,426,and 775 cfs.These data were used to cal ibrate an IFG-4 model.A gravel bar extends diagonally through the study reach and forms the riffle at cross section 3.At low side channel flows,the angle of flow is altered and differences as large as 0.60 ft occur between left and right bank water surface elevations.Since the IFG-4 model requires a horizontal water surface elevation at each cross section,the 0.60 ft difference in right and left bank water surface elevations had to be adjusted.The largest portion of"flow occurred to the right of the gravel bar,therefore the streambed elevations used in the IFG-4 model for cross section 3 were determined by subtracting the measured depth of flow at each vertical from the right bank water surface elevation associated with the 23 cfs discharge.The streambed profile,elevation of zero flow,and observed and predicted water surface elevations for the study reach were plotted to scale (Figure 7-3-37). The backwater effects at cross sections 1 and 2 can be observed for the 775 cfs flow.Because of the large gap between the 23 and 426 cfs data sets and the divergence between predi cted and observed water surface elevations,an additional data set was simulated.A side channel flow of 100 cfs was selected as approximating the side channel flow which fully wetted the streambed and served as the transition between low flow and high flow regimes. A two-flow IFG-4 model was prepared for high flow conditions based on the 426 and 775 cfs data sets and used to predi ct a water surface profile at 100 cfs (Figure 7-3-38).This profile was as much as 0.65 ft lower at cross section 1 than the profile forecast by the three-flow model previously calibrated using flows of 23,426,and 775 cfs. However,at the upstream cros s secti ons,both predi cted water surface profiles compared favorably.The mean of these two predicted water surface elevations were used as the representative profile for a 100 cfs synthesized data set.Little difference existed between the magnitude of the velocities simulated by either model for 100 cfs.Therefore,the velocities predicted by the three-flow model were used with the 100 cfs profile,thus forming a four-flow hydraulic model for the study reach. 7-3-64 - .... - - - 1 1 1 1 1 ]j 1 1 ~ 740-SIDE CHANNEL 21 738- •--- CROSS-SECTION NUMBER ... --. J'ij;iJilit -- LEGEND ---- • •--- •Obnrved Waler Surface EIIl/Olio" - - - -Prelihlil)orr Simulated Wale,SurfQc.Elevation ---Elevotiu!)of Zera Flow ~Grave'I Rubble ~Cobble/eould...AD'••SU HYDIO.1983 --_..........,,-- I' //~--- /" /" /""/ /"//\~;~---_/,,/ ",./ '!l("~~",,,/'1-_- ," .--,- --,,-- ____Jl~~!!•_/"",,/.----"...-,/ _~__1~8_cJ ~-/// •• ..,- 733 -+-Point 01 Z"o Flow IA~8.FJi~~rt"°l:~~o~D ~.,:oQ~t:-Pli llk' }."o$lfj.:O?8.~~Y J6,'l.":.tI,{'o'!iW 2 3 4 5730~J·;;d I I I I 736 - 732 731 ..737 -••... ~ Z 0 736 I-oa:> 111 oJ 1&1 7311 111 ::l II: I- 734 '-J I W Im U"I -38+92 -37t07 ·35+74 -33+42 -30"'06 STREAM B ED STAT ION I feet! Figure 7-3-37.Comparison of observed and predicted water surface profiles from non-calibrated model at Upper Side Channel 2f study site. 740 SIDE CHANNEL 21 CROSS-SECTION NUMBER ----....-- _.....~ ---.....-..... ADF8a SU HYDRO.1983 --- L.EGEND 4 II ..-"......----_r Observed Water Surface Elevation Prel iminarv Simulaled Wole,Surface Elevation Elevation of Zero Flow Gro.ell Rubble Cobblel Boulder • ~ ~ --- --- I2 I- I I I I I I I I I I I I ,~~~~--j .....,..-- ~ ~ ~ ~-•L~5~~~- ,...-- / / / / / / / / / a--__~~6_c.!..__-... 759 758 o.~:<'.>'--+--Poinl 01 Ze.o F]£OW.ll.·o·.·i>~~____."t~··.·o 01 -41 +15.~~o;b·~ ;ft.(!! ~Q,;;~i" Ii"'"730 J ~'ne I I I I 751 732 757 ~-lI> .:?758 ~ z 0 I- <X 7511> I1J ..I I1J I1J 734 -....,J ~ II:: W l- I 0\ 0\733 -38+92 -37+07 -3!it74 -33T42 -30+06 STREAMBED STATION (feet) Figure 7-3-38.Comparison of observed and predicted water surface profiles from non-calibrated model at Side Channel 21 study site. J I I J ~I »J _I J I I ~!!.~I;~ - - A 1,500 cfs flow was determined as the upper limit of extrapolation and its predicted water surface profile was plotted with the water surface profiles for the four calibration flows (Figure 7-3-39).The difference between the observed and predicted profiles at cross sections 1 to 3 was reduced by dividing the IFG-4 hydraulic model into two separate models to better simulate the backwater effect present at the mouth of the side channe 1 when side channel flow is 100 cfs or 1arger •.One model is for no backwater conditi ons with the 23 and 100 cfs data sets (Fi gure 7-3-40)and the other is for backwater conditions with 100,426,and 775 cfs data sets (Figure 7-3-41). To evaluate the reliability of the IFG-4 hydraulic models observed and predi cted water surface e1 evati ons,di scharge and velocity adjustment factors were compared (Appendix Tables 7-A-18 and 7-A-19).The maximum difference in water surface elevations for each calibration flow was 0.02 ft at the five cross sections.The mean calibration discharges predicted by the IFG-4 hydraulic models were 23,100,431,and 776 cfs, as compared to input values of 23,100,426,and 775.The vel oci ty aqjustment factors for both models ranged from 0.96 and 1.05. 3.3.7.4 Verification Two models were developed for this site because backwater effects were present at the mouth of the side channel and in the study site when side channel flows were 100 cfs or greater.Therefore,the upper extrapolation limit for the two-flow model and the lower limit for the three-flow model is 100 cfs.For Side Channel 21,the two-flow model (23 and 100 cfs)describing no backwater conditions has an extrapolation range from 20 to 100 cfs.This corresponds to Susitna River discharges below 12,000 cfs.The three-flow model (100,431,and 776 cfs) describing side channel flow with backwater conditions present at the mouth of the side channel has an extrapolation range from 100 to 1,500 cfs.This corresponds to Susitna River discharges at Gold Creek of 12,000 to 30,800 cfs (Figure 7-3-42). A comparison was made between water surface elevations predicted by the IFG-4 hydraulic models for selected flows at cross section 4 and the empirical rating curve developed by ADF&G (Figure 7-3-43).Results of the ana lysi s of covariance tests i ndi cated that the two curves had equivalent intercepts and slopes (Appendix Tables 7-A-20 and 7-A-21). Depths predicted by the low flow model for Side Channel 21 were similar to the observed values (Appendix Figure 7-A-8;r=0.94).A total of 77 predicted values out of a total of 171 (or 45%)were considered poor. The majority of these "poor"predi cti ons occurred for depths 1ess than 0.5 ft,and were extremely close to the cutoff bounds.Comparatively, the velocities were predicted better by the low flow model (r=0.94).A total of 49 predicted values out of 171 (or 29%)were considered poor predictions.However,an number of these poor predictions were considerably off of the observed values;and occurred at observed ve10cites of 0.0 ftjsec. The hi gh flow model predi cted depths with a hi gh degree of accuracy (Appendix Figure 7-A-9;r=0.99).Only 28 out of 704 (or 5%)predicted depths were considered poor predictions.Velocities were also predicted 7-3-67 740 SIDE CHANNEL 21 739 ---- '- CROSS-SECTION NUMBER5 -- -_.. -30+06 -- ,- --'--- ---~_.....- -,...- ~~.~;~~'fl.~iq~·~~;~~i"ff{~~,;,Q'.1'0!l.6·.~Jl"••. .,.~·:·po.•.si~~·oo . ---_......-,-,---- -' -- ---_....- LEGEND -- 4 -33+42 ---....- •ObSOfved Watsr Sur'ace Elevation Preliminary Simulated Waler Sur'ace Elevation ___Elevation of 7..fO Flow ~1 Gr •••1 I Rubbl. ~Cobble IBoulder ADFae SU HYDRO,1985 --------~~~~~~;---- 3 --- -35+74 2 -37t07 ___I:~O-C!..-__----- .....----- ------ I!.....~- - /~-_...------ ,,'------- ,,/~--- ",I..,,// ..]!~:'f':_.....__~""'""./ ,1,1 ,I ,I 431 eft,/'.-------------... 730 I tW '""I I I I -38+92 733 735 732 734 737 738 736 731 .. II II ~ Z ~... "l:> 111 ...J 111 111 -.....,I :J I Ir W ... I 0'1 CO STREAMBED STATION (feell Fi gure 7-3-39.Comparison of observed and predicted water surface profiles from non-calibrated model at Side Channel 21 study site. J J t 1 I J I ,,J J J J ,!J J J J I }1 J J J -,1 1 1 1 1 1 1 1 730'r-v"i'~>I I I I 739 738 737 -736••...-z 0 7.3~ .... -t>.... ..J '-J ....734 I W .... I =» 0'\ a: \D ....733 732 731 SIDE CHANNEL 2\ ] Extrapolation Range of Hydraulic Model ..--~11l!llf$1:f1;'ti'l,j~~,}j LEGEND •Observed We1er Surface ElevQ!ion S imuluI8a Watef Sutfoce Elevotion Elevation of Zero Flow E::l Gravel/Rubble ~Cobble /Boulder ADF"Q SO HYDRO,1981 4 ~CROSS-SECTION NUMBER -38+92 -37+07 -3li+74 -33+42 -30 ofl 06 Fi gure 7-3-40. STREAMBED STATION (teet) Comparison of observed and predicted water surface profiles from calibrated model at Side Channel 21 study site for low flow regime. L ltj~iJj,t:¥II. LEGEND --------}Eklropolotion __------~Ronge 01 ____~~~~~~~UliO •Observed Water surface Elevd'ion --Simulated Water Surfac.EI.Vdt ion ---Eklropolol.d Woter Surlo ••EI ••ol ion ---EI ••olion of Zero Flow ~Gro ••I/Rubbl. Ii!:S3 Cobbl./Boulder ADfaG SU HYDRO.1983 -------- 776.r. 431 e!s __1':000 I._______ SIDE CHANNEL 21 737 738 739 7311 736 734 732 733 731 730'f C.<V~i 3 4 CROSS-SECTIONIIiNUMBER ..••...-z 0 t-ee>w ..J W "-J W I ;:) W 0: I t- "-J 0 -38t92 -37+07 -35+74 -33+42 -30+06 STREAMBED STATION (feet) Fi gure 7-3-41.Comparison of observed and predicted water surface profiles from calibrated model at Side Channel 21 study site for high flow regime. J ~),I I .1 J •I j I I !I I J ] !"", ..,. -.,.. Co)- (\J ..J l&J Z Z <l ::z::: (.) l&J C-U) 10,000 9,00 8,00 7.000 6,000 5,000 4.000 AOF a G Flow Ve.nus Discharge Curve for Side Channel 21 ~ Qsc=IO-II.0238{QMS13.1632 ~ (12.000.76 ) Side channel flow determined by local runoff and upwelling for mainstem discharge below a breach- ing discharge of 12.000cfs. LEGEND •Coincident moinstem discharge and side channel flows at which cali bra!ion da!a were collected. Recommended Extra- poation Range of the ~Hydraulic Models under Moinstem Con- trolled Discharges. I0 ......---....-....-0111~......,...""""...---.....-..,.-...........~..,... 2 4 6 8 10 20 40 60 80 100 ---_.---.'----._-".-----,"". MAINSTEM DISCHARGE AT GOLD CREEK (x IOOOcfs) Figure 7-3-42.Relationship between extrapolation range of Side Channel 21 low and high flow models and ADF&G flow-versus-discharge curve. 7-3-71 ..__.•__•0.•_ 731 1 'ii', , ,"'ii', , , " , 7150 I Extrapolation range I Extrapolation range of high f low model I......"of low flow model -Rating curve from observed water surface elevations and discharge measurements at ADF8G staff gage 140.654. A Predicte-d water surface elevations from calibrated hydraulic mode 1s. .&.- •• LEGEND .I I &•a 733 732 740 739 738 737 736 735 734 zo-~~ -I I&J bJ (,) ~ 0:=» U) 0: I&J fc~ -..••It-- .. -.......J I W I -.......J N 10 20 40 60 80 100 200 400 600 800 IPO 0 2,000 SIDE CHANNEL 21 DISCHARGE (cfa) Figure 7-3-43.Comparison between ADF&G rating curve and model predicted water surface elevations. I J )1 I I J ,I J l j J I J )t ,) F"". ~ ! accurately by the high flow model (r=0.99),with 51 predicted velocites out of 704 values (or 7%)cons i dered poor.A few of these poor predictions were substantially different from the observed values and occurred at an observed velocity of 0.0 ft/sec. 3.3.7.5 Application The study site in Side Channel 21 was chosen to represent potential chum salmon spawning and juvenile salmon rearing habitat in the free-flowing portion of the side channel (Estes and Vincent-Lang 1984:Chapter 2, Figure 2-8).In general,this extends from station -50+00 to -4+57 for unbreached condi ti ons and -38+92 to -4+57 when the channel is rna i nstem controlled.Downstream of station -38+92 depths and velocities within the side channel are more significantly influenced by mainstem backwater effects than by side channel flow.Hence,the high flow hydraulic model for Side Channel 21 should not be applied to this portion of the side channel. Calibration data were available for side channel flows of 23,431,and 776 cfs.Prelimi'nary calibration runs indicated that the flow range between the 23 and 431 cfs data sets was too great to simulate with an acceptable degree of confidence.Therefore,it was assumed that the bed of the side channel became fully wetted at a flow of 100 cfs (the transition from low to high flow conditions)and a calibration data set for 100 cfs was simulated (Section 3.3.7.3).This assumption and cali- bration technique have greatly improved the plausibility of the hydrau- lic model throughout its calibration range.It must be remembered, however,that the calibration data for the 100 cfs flow were simulated and not measured values.Subsequent analysis suggests that the transition flow might be closer to 60 or 70 cfs rather than 100 cfs. Used in conjunction with one another,the Side Channel 21 hydraulic models will span a range of side channel flows between 20 and 1,500 cfs. Side Channel 21 is mainstem controlled via Channel A5 when mainstem discharge exceeds 12,000 cfs.During breached conditions,the side channel flows range from 100 to 1,500 cfs which corresponds to mainstem discharges of 12,000 to 30,800 cfs.At mainstem discharges less than 12,000,side channel flow is maintained by clear water inflow from Slough 21 and upwelling.Unbreached slough flows are generally in the range of 20 to 30 cfs and should be modelled by the low flow model. 3.4 DISCUSSION Ten hydraulic models were calibrated for seven slough and side channel locations.Several of these models were developed to account for a sma 11 amount of channel change (Slough 9)or varyi ng degrees of flow resistance present under high and low flow conditions (Slough 8A,Slough 21,and Side Channel 21).Comparisons between corresponding sets of forecasted and measured·hydrau 1ic parameters i ndi cate that the models provide reliable estimates of depths and velocities within their recommended calibration ranges. In three instances,field data were limited and synthetic data sets were used to calibrate models for Slough 9,Upper Side Channel 11,and Side 7-3-73 Channel 21.Although the forecasts of these calibrated hydraulic models cannot be compared to measured depths and velocities,the models appear to provide reasonable forecasts of depths and velocities. Relationships have also been defined between a site specific flow and mainstem discharge at the USGS stream gage at Gold Creek (Table 7-3-9). When the mainstem discharge is sufficient to control the channel flow, the flow rate through the study site is directly dependent upon the mainstem discharge. When the mainstem discharge is too small to control the channel flow, the flow rate through a study site is dependent upon local surface runoff or groundwater inflow.A correlation cannot be demonstrated with existing data between site specific flow and mainstem discharge when sloughs or side channels are not breached.Site specific flow rates for unbreached conditions can only be estimated on the basis of field observations and a limited number of instantaneous discharge measurements. The hydraulic models are intended to support an analysis of the effects of incremental changes in flow on the availability of salmon spawning and rearing habitat in side sloughs and side channels.The models may be used to forecast flows outside the recommended extrapolation ranges, however,the reliability of the models deteriorates outside these ranges. The utilization of various depth and velocity combinations by spawning salmon in slough habitat is discussed in the following section of this report. 7-3-74 - - - 1 ·1 -1 -J ]-.._J }-I J ]1 )····1 J ]j Table 7-3-9.Summary of comparison of mainstem discharges at Gold Creek for which extrapolation ranges of IFG models apply streamflow at IFG model sites (cfs)1 Mainstem Lower Side Discharge Channel 11 A B Side Channel 21 A B Upper Side Channel 11 A B Side Channel 10 A B Slough 9 A B Slough 21 A B Slough 8A A B -...,J I W I -...,J (J"l 8,000 10,000 12,000 14,000 16,000 18,000 20,000 22,000 24,000 26,000 28,000 30,000 32,000 34,000 400 640 I900 1,200 1,500.. 1,900 20002,200 2,600 3,100 3,500 4,000 4,400 4,900 5,500 6,000 20 30 30 76# 120 190 270 380 520 680 870 1,100 1,400 15001,700 2,000 5 5 5 5 5 25# 45 77 120 190 250290 420 600 830 1,100 5 5 5 5 5 5 5 16# 35 74150 100 280 500 870 1,500 5 5 5 5 5 5 5 14 34 75 160 300 570 1,000 600 1,800 5 5 5 5 5 5 10 10 10 10# 23 54 120 240480 400 4 10 10 10 10 10 10 10 10 10 10 10 10 10 28#70 Mainstem Controlled Discharge at Gold Creek *12,000 16,000 19,000 19,000 24,000 33,000 1 Slough and side channel flows determined by the ADF&G flow-versus-discharge curves. #Site specific flow becomes a function of mainstem discharge at Gold Creek. Channel A6 Upper in Slough 21 Complex breaches at 18,000 (Gold Creek). *Undefined at this time Extrapolation range of hydraulic models. A Flow associated with mainstem discharge. B Calibration range of models. - - .""F , I 4.0 FISH HABITAT CRITERIA ANALYSIS 4.1 Introduction This section presents the results of the second step of the IFIM PHABSIM modelling process.A discussion is presented of the spawning habitat data collected at chum and sockeye salmon redds in slough and side channel habitats in the middle reach of theSusitna River,the methods used to analyze the data,and the resulting suitability criteria developed for chum and sockeye salmon spawning in slough and side channel habitats of the middle reach. Fish habitat criteria studies were initiated in 1982 with the objective of collecting sufficient measurements of selected habitat variables (depth,velocity,substrate,and upwelling)at individual chum and sockeye salmon redd sites (henceforth referred to as util izati on data) to determi ne the behavi ora 1 responses of spawni ng chum and sockeye salmon to the various levels of these selected habitat variables.The collection of availability data,that is,the combinations of the various habitat variables which were available to spawners (Reiser and Wesche 1977;Baldrige and Amos 1982),was limited to the hydraulic simulation modelling study sites. Spawning utilization data collected in 1982 were inadequate to develop spawning suitability criteria due to low discharge and flow conditions 1 imiti ng access of adult chum and sockeye salmon into study sites.A summary-of the 1982 data and the modified analysis used to evaluate the utilization data is presented in AOF&G (1983b,Appendix 0). Additional utilization data were collected in 1983 which when combined with 1982 data,information from literature,and professional judgment of project biologists,were sufficient for developing chum and sockeye salmon spawning suitability criteria for use in the IFIM PHABSIM modelling process.All results and conclusions relating to chum and sockeye spawni ng su itabil ity ins 1oughs and side channels in the mi ddl e river reach which are presented in this chapter supersede those presented in earlier ADF&G Su Hydro reports. 4.2 METHODS 4.2.1 Site Selection Site selection for the collection of utilization data in sloughs and side channels of the mi dd 1e ri ver reach was based on the presence of spawning salmon and the ability to observe their activities.Data collection efforts were concentrated in the areas of the sloughs (Sloughs 8A,9,and 21)and side channels (Side Channels 21 and Upper 11)where hydraulic simulation modelling data were being collected to enable field staff to maximize the collection of combined utilization and availability data (used to evaluate preference).Other sloughs and side channels in the Talkeetna to Devil Canyon reach were also surveyed for spawning activity and if present,selected as additional study sites to extend the utilization data base.The non'-modelled sites included 7-4-1 Sloughs 9A,11,17,20,and 22 (Figure 7-4-1).Availability data were not collected at these non-modelled sites. Utilization data were also collected in tributary mouth habitat locations.These data were not included in this analysis due to their inapplicability to side slough and side channel habitats,but are discussed in Chapters 8 of this report,respectively,in relation to their associated habitat types. 4.2.2 Field Data Collection Spawning salmon were located at each study site by visual observation. Biologists observed fish activities from the stream bank for 10 to 30 minutes to determine active redd locations prior to entering the water for measurements.An active redd was defined by the fanning of a female at least twice during this period and the presence of a male exhibiting aggressive or quivering behavior.The type of behavior observed for each redd was noted.Detail ed descri pti ons of the criteri a used to identify active redds are presented in Estes et ale (1981)and Tautz and Groot (l975). Water depth and velocity measurements were collected at the upstream end of each active redd using a topsetting wading rod and a Marsh McBirney or Price AA meter.The typical substrate composition in the depression of each redd was visually evaluated using the size classification scheme presented in Table 7-4-1.A visual assessment of the presence of upwelling in the vicinity of the redd and the distance to the upwelling from the redd were also noted. For redds evaluated within hydraulic simulation modelling study sites, staff gage readings were also recorded.These were used to estimate the flow (via rating curves presented in Chapter 1 of this report)at the time redd measurements were obtained which were then used to simulate available depth,velocity,and substrate data which were used in the evaluation of preference and subsequent derivation of the spawning suitability criteria.~, -Table 7-4-l.Substrate classification scheme utilized to evaluate substrate composition at spawning redds. ~ Substrate Category Size Class Silt Very Fines Sand Fines Fine Gravel 1/8-1" Course Gravel 1-3 11 ~. Cobble 3-5" Rubble 5-10" Boulder greater than 1011 Fm 7-4-2 ~ 10 I SLOUGH 22 MILES o I UPPER SIDE- Figure 7-4-1.Side slough and side channel locations where fish habitat criteria data were collected. 7-4-3 4.2.3 Analytical Approach The primary objective of this portion of the study is the development of weighted habitat criteria for use in the IFI'M PHABSIM system models for calculation of WUA.Weighted habitat criteria representing microhabitat preferences of fish habitat are usually expressed in the form of "habitat curves".These curves describe the relative usability of different levels of a selected habitat variable for a particular species/life phase,with the peak indicating the greatest usability and the tails tapering towards less usable values.Curves are typically developed for each habitat variable considered to influence the selection of habitat for the species/life phase of interest (Bovee and Cochnauer 1977;Bovee and Milhous 1978). Three types of curves are commonly constructed:habitat uti 1i zati on, preference,or suitability curves.Habitat utilization curves typically consist of a plot of values obtained from field observations and represent the range of conditions utilized by the species/life phase under study without taking into consideration the range and amount of habitat present (Bovee and Cochnauer 1977).Habitat preference curves take into consideration the range and amount of habitat present for the species/life phase to use (available habitat)and weight the utilization information accordingly,as discussed in Reiser and Wesche (1977), Baldrige and Amos (1982),and ADF&G (1983b).Habitat suitability curves are a modification of either a utilization or preference curve based on results from literature and/or the professional opinion of biologists familar with the species/life phase under study in order to extend the usable range of the curve beyond the range determined based on utilization and/or preference data. Typically,these curves are constructed by plotting standardized scaled criteria index values indicating relative utilization,preference,or suitability (depending on the curve type being evaluated)on the y-axis versus the habitat variable to be evaluated 011 the x-axis.The criteria index is scaled between 0 and 1,with 1 denoting the greatest habitat utilization,preference,or suitability and 0 denoting no utilization, preference,or suitability. The criteria index values are then used in a habitat simulation model to calculate composite suitabiltiy factors to "weight"each cell (as defined by transects in the study area)in terms of its relative usability as habitat for the species/life phase under study.The weighted cell usabilities are then summed for the entire site at each evaluated flow level to calculate a total WUA for the site (see section 5.0). Depending on the available data base,utilization,preference,or suitability criteria indices can be input into the habitat simulation model to weight each cell.In this report,sUitability criteria indices for the habitat variables of depth,velocity,substrate,upwelling,and a composite index representing substrate and upwelling were developed 7-4-4 - - - - - all values which are less than or equal to 0.1,including all 0.0 values.Additional incremental plots of substrate are not appropriate because substrate data is not continuous. Following standardization,the various utilization curves developed from these data groupings were evaluated in order to select a "best" utilization curve based on the following criteria: 1.Minimal sample variance of frequency counts;that is,lower variability among the frequency counts; 2.Minimal coefficient of variation for the frequency counts (i.e.,the sample standard deviation of the frequency counts divided by the sample mean of the frequency counts); 3.Minimal irregular fluctuations,"meaning grouped values should continually increase to the maximum grouped value,then continually decrease",as defined by a series of four indices proposed by Baldrige and Amos (1982);and, 4.Minimal peakedness,meaning a minimal difference between the maximum grouped value (i .e.,increment)and the increments immediately below and above the maximum,as defined by a peakedness index described below. The first three evaluation criteria are the same as those described by Baldrige and Amos (1982).The fourth evaluation criterion is proposed as a method of quantifying a characteristic of the utilization curves which has been subjectively evaluated in previous studies (per.comm.D. Amos 1984).Subjective evaluation of curves would occur in previous studies if the first three criteria failed to indicate one IIbest ll curve. The four evaluation criteria were weighted in terms of their application as curve selection tools.The minimal variance and irregular fluctuation evaluation criteria were weighted most strongly while the coefficient of variation evaluation criteria was only used to separate curves which were otherwise indistinguishable.The peakedness evaluation criteria was intermediate in importance between the irregular fluctuations and the coefficient of variation evaluation criteria. The first of the above evaluation criteria,the minimal sample variance of frequency counts,is an adaptation of the chi-square criterion proposed by Bovee and Cochnauer (1977).Sample variance is used as opposed to chi -square criteri a in order to allow for compari son of histograms developed with non-count type data (e.g.,the ratio of utilized versus available counts).Although use of the chi-square criteria is possibly more appropriate in the case of the count data used here,the use of the sample variance of counts (or ratios)can be applied in a wider variety of circumstances.In general"this criterion should only be applied when the total number of different increments utilized is reasonably large,probably greater than 5 but at least greater than 2.If the sample size is so small that very large increment sizes (e.g.,0.5 ft or 0.5 ft/sec in this case)are necessary 7-4-7 Table 7-4-2.Summary of histograms used to evaluate depth and velocity utilization data. - ~ Histogram Increment Size Increment Starting Value 1*0.1 0.0 ~ 2 0.1 0.1 3 0.2 0.0 4 0.2 0.1 5 0.3 0.0 ~ 6 0.3 0.1 7 0.3 0.2 ,"""" *Histogram 1 was not developed for depth (see text for explanation). 7-4-6 """ - - - ~. - for chum and sockeye salmon spawning in slough and side channel habitats of the middle Susitna River following the methods described below. Depth,Velocity,and Substrate Spawning Suitability Criteria Development The first step in development of depth,velocity,and substrate spawning suitability criteria indices involved an evaluation of the depth, velocity,and substrate utilization data collected in slough and side channel habitats of the middle Susitna River.This was accomplished by plotting the depth,velocity,and substrate utilization data for each species as frequency histograms.The data were standardized by dividing the frequency of observations in each increment of the appropriate habitat variable by the frequency of observations in the increment with the highest occurrence.This standardization achieved a a to 1 scaling index for frequency on the y-axis.The resultant scaled frequency histograms represent the utilization "curves 'l described earlier. The original scale of the increments used in the frequency analysis corresponded to the measuring accuracy for the particular habitat variable of interest.Accordingly,depth and velocity histograms were initially divided into 0.1 ft and 0.1 ft/sec increments,respectively. Substrate hi stograms were divi ded into di screte substrate-cl ass increments (e.g.,silt,silt-sand,sand,etc). Additiona 1 hi stograms were constructed for depth and velocity utilization data in order to ensure development of utilization curves which did not exhibit spurious characteristics such as irregular fluctuations or multi-modal structures.Because utilization curves are developed for one species/life stage,it is assumed that there should only be one most utilized increment of a particular habitat variable and that the curves should be rel~tively smooth (i.e.,no irregular fluctuations).As sample size is increased,it is expected.that utilization curves developed from increments at the original measuring accuracy will approach the ideal of uni-modal structure and smoothness. Small sample sizes and the resultant large increments,however,often lead to curves exhibiting multi-modes and irregular fluctuations.For these reasons,additional scaled frequency histograms were developed for depth and velocity increments of size 0.2 ft and 0.2 ft/sec and 0.3 ft and 0.3 ft/sec. Several groupings of the data are possible if increment sizes of 0.2 and 0.3 are used,depending on the starting value of the increment.Because of thi s,a tota 1 seri es of six scaled hi stograms were developed for depth and seven for velocity as summarized in Table 7-4-2.The seventh scaled histogram (Histogram 1)was constructed for velocity such that the first increment consisted only of 0.0 ft/sec velocity measurements as velocities of 0.0 ft/sec were used for spawning.Construction of this histogram was not warranted for depth,as depths of 0.0 ft were not utilized for spawning.Histogram 1 differs from Histogram 2 only in .that Histogram 1 groups all observed values that are equal to 0.0 into the first increment,while the first increment in Histogram 2 contains 7-4-5 to reduce irregular fluctuations or avoid multi-modes~then the variance criterion should not be used as it may lead to artificially flat (i.e.~ heavy-tailed)curves. The minimal variance criterion was applied in only those instances when the difference between vari ances was stati st i ca lly si gnifi cant. Levene1s W test for homogeneity of variance (Brown and Forsythe 1974; Glaser 1983)was executed to evaluate the similarity of the variance of frequency counts between the various scaled frequency histograms.The test is robust since it does not require that the data be normally distributed.The hypotheses tested were: HO:All variances are equal; Ha :At least one of the variances are different. If the null hypothesis was rejected,then individual pairs of variances were compared.The ratio of the larger variance value to the smaller variance value provided an F statistic which could be evaluated for significance using standard F tables (Dixon and Massey 1969).The hypotheses tested were: One of the variances is the same as one particular variance of the other five (or six); "'"' - ~. A series of 15 to 21 possible pairwise comparisons were made.The comparisons between histograms with smaller variance values were those of primary interest (except in cases of violation of the third criteria above;that is~minimal irregular fluctuations). Evaluation of the third criterion was based on a series of four indices as described in Baldrige and Amos (1982): 1.Number of irregular fluctuations (number of times grouped va 1ues decreased pri or to the max imum value and increased after the maximum value); H •a"One of the variances is not the same as one particular variance of the other five (or six). - 2.Total magnitude of irregular fluctuations: M.V.* ~[group (i_l)-group(i)]+ i=2 L.G.* ~[group (i)-group(i_l)] i=M.V.+l where~ M.V.=maximum value L.G.=last group *=only when this difference is greater than 0 7-4-8 - - - 3.Maximum of the individual irregular fluctuations (largest difference computed in number 2 above prior to any summing); and, 4.Average fluctuation (total magnitude of fluctuations/number of irregular fluctuations). The best curve should have small values for all four indices. irregular The minimal irregular fluctuation criterion sometimes led to rejection of the histogram selected best with minimal variance criteria. Rejection of minimal variance histograms due to this criteria involved professional judgment as to the relative tradeoffs involved.These tradeoffs generally involved choosing between a non-smooth curve with many increments and a smooth curve with fewer increments (often with a hi gher variance).A non-smooth curve with many increments was often indicative of low numbers of observations (i.e.,frequencies). The peakedness criterion was evaluated using a peakedness index defined as: Index = where, (-F(m_l)+2(F(m))-F(m+l)) (F(m_l)+F(m)+F(m+l)) represents the frequency of the increment immediately below the maximum increment; represents the frequency of the maximum increment; and, represents the frequency of the increment immediately above the maximum increment. A modification of the above formula was implemented in cases where the peak occurred in the first or last increment of the curve.In this case the fonnula used was: Index = where, F(m)-F(x) F(m)+F(x) F(x)=F(m+l)when F(m)was the first increment of the curve, or F(X)=F(m_l)when F(m)was the last increment of the curve. 7-4-9 If more than one peak existed the max"imum index value was evaluated. This index has a range of O~indicating a gradual peak~to 2 indicating a sharp peak.Genera11y~the lower the index the better the curve. The peakedness criterion as defined above is a measure of the degree of difference between the most frequently occurring increment (i.e.~with a scaled frequency of 1)and the increments to either side of this increment.As such~it does not necessarily preclude curves which are highly peaked (i.e.~with large kurtosis 1eve1s)~but does ensure against artificially high peaks due to an arbitrary choice of the method of grouping.This criterion should be applied only in situations where the width of individual increments is sufficiently small (i.e.~when the total number of increments is greater than 5)such that the peak increment would be expected to be surrounded by increments which are of similarly high occurrence.For examp1e~if the increment size is 0.5 ft and the true optimal depth is 0.8 ft~then the increments of 0.0 to 0.4 ft and 1.0 to 1.4 ft might very well have very low values as compared to the increment of 0.5 to 0.9 ft. This criterion was established primari1y as a means of quantifying (and therefore a110wing for repeatability)a subjective criterion which had been previously used to evaluate curves which could not otherwise be distinguished.The criterion of minimal peakedness was only evaluated when the resulting best curve did not seriously violate the minimal irregular fluctuation criteria.Peakedness indices were evaluated to be Udistinguishab1e ll when they differed by +10%from each other.Specific decisions made during the selection of the best utilization curves are presented more fully in the results section. Caution is necessary when applying the above criteria for curve selection.Hypothetically~a curve which is radically different from the original observation curve (for example the median or mean variable value is altered greatly)might incorrectly be chosen as the best curve. Additionally,a curve which is artificially too flat (heavy-tailed) might be selected if sample sizes are very sma11.For these reasons~a comparison of the selected Ubest"curve with the original observations as well as a review by biologists familiar with the species evaluated were made.Specifi ca lly ~compari sons of the means and vari ances of the non-incremental data with the means and variances of the incremental data were made.In no instance of the analysis presented in this chapter was a Ubest ll curve judged to be unreal i sti c based on these considerations. The last step used in the development of suitab"ility criteria indices for depth~velocity,and substrate was to modify the best utilization curves selected for depth,ve10city~and substrate on the basis of habitat availability data (i.e.~evaluation of preference)and professional judgment using previously published data and the opinion of project biologists fami1ar with middle Susitna River chum and sockeye salmon stocks. Low escapement and low flow conditions during 1982 and 1983 limited collection of utilization data in areas which were evaluated with 7-4-10 ~ I "... --I I :1 hydraulic simulation models.As most of the additional utilization data were collected in areas outside of the hydraulic simulation modelling study sites where no availability data were collected,the analysis of preference for selected habitat variables could only be based on the limited amount of utilization and availability data collected within the modelled sites.For these reasons,the analysis of preference was only used to refine the best utilization curves based on professional judgement. Preference was evaluated by considering the scaled frequency of use of each habitat variable increment utilized in relation to the scaled frequency of that habitat variable increment available to select from. This was accomplished by comparing the utilization data collected within a specific study site at a particular flow with availabil ity data generated by the hydraulic simulation model for th.at site and flow,then compositing these data for all sites and flows.Because upwelling was assumed to be the controlling factor in selection of spawning areas (i.e.,spawning only occurs if upwelling is present),only availability data specific to areas of upwelling were used in this analysis. The configurations of water depths,velocities,and substrates available at upwelling locations within the modelled study sites were simulated for the flows at which within-site utilization data were collected. Availability data for each flow and site were then weighted according to the relative number of redd measurements taken and combined in the form of scaled histogram plots.The groupings of the avai'lability data corresponded to the increments specified by the associated best utilization histograms.The frequency of observations within each increment of the availability data were then compared with the corresponding values from the utilization data.. Because substrate availability data were collected at a finer level of resolution than substrate utilization data,a reduction in the level of resolution of the utilization data collected was necessitated in order to evaluate preference.This was accomplished by reclassifying substrate availability data size classes 1 and 2 as silt,classes 3 and 4 as sand,classes 5 and 6 as small gravel,classes 7 and 8 as large gravel,classes 9 and 10 as rubble,classes 11 and 12 as cobble,and class 13 as boulder (Table 7-4-3). Preference for each increment of a habitat variable was then evaluated as the ratio of utilized to available habitat within a study area,with values of less than 1.0 indicating a lesser degree of preference and values exceeding 1.0 reflecting a greater degree of preference (Voos 1981;Prewitt 1982;Baldrige and Amos 1982). The preference data were then subjectively evaluated in conjunction with additional field data,published information,and the professional opinions of project biologists familiar with middle Susitna River salmon stocks to modify the best utilization curves for'each habitat variable into suitability criteria as described in the appropriate results section. 7-4-11 Table 7-4-3.Grouping of substrate classification schemes used to evaluate substrate preference. -General Substrate Category Particle Size Detailed Substrate Classification Si lt Silt 1 2 f'!'" Sand Sand 3 4 ~ Small Gravel 1/8-1 11 5 6 .... Large Gravel 1-3 11 7 -8 Rubble 3-5 11 9 - 10 Cobble 5-10 11 11 """'! 12 Boulder 10"13 1I\IlI'9', 7-4-12 .~ .,... I The methodology described above was used to develop suitability criteria for the habitat variables of depth,velocity,and substrate for adult chum salmon spawning in sloughs and side channels of the middle Susitna River.The same methods were used to develop suitability criteria for adult sockeye spawning with the exception that the approach did not include an analysis of preference.Insuffic.ient utilization data were collected at hydraulic simulation modelling study sites to permit an analysis of preference for the habitat variables of depth,velocity,and substrate.For thi s reason,the suitabil ity criteria for adult sockeye spawning in side sloughs and side channels were derived from best utilization curves which were refined by professional judgment using previously published data and the opinion of project biologists familiar with middle Susitna River sockeye salmon stocks. Upwelling Spawning Suitability Criteria Development Due to the difficulty of measuring upwelling rates within the ranges detectable by spawning salmon,suitability criteria for the upwelling habitat variable for spawning chum and sockeye salmon were developed using a binary criteria approach (Bovee 1982).This was accomplished by assigning a suitability index value of 1.0 to lI upwe lling present ll and a suitability index value of 0.0 to lI upwe lling absent ll •The assignment of a suitability index value of 1.0 to upwelling present is predicated on extensive fi el d observati ons concerni ng the behavi or of spawni ng chum and sockeye salmon in sloughs and side channels of the middle Susitna River (ADF&G 1983b).Chum and sockeye salmon spawning has primarily been observed in areas of side sloughs and side channels where visual evidence frequently indicated that upwelling was present~Additionally, winter observations of spawning areas (used to locate upwelling by the presence of open water leads)generally confirmed the presence of upwelling in those areas where no visual evidence of upwelling existed at the time of spawning observations. Combined Substrate/Upwelling Spawning Suitability Criteria Development The hydraulic simulation models used to project usable area of spawning habitat (refer to section 5.0)can only accommodate a maximum of three habitat variables,two of which (depth and velocity),are integral to the operation of the model.Because substrate and upwelling are both considered important habitat variables for chum and sockeye salmon spawni ng,a combi ned substrate/upwell i ng suitabi 1ity criteri a index was developed for use in the habitat simulation model.This was accomplished by multiplying the weighting factors of each of the possible combinations of substrate and upwelling criteria.This resulted in a value of a being assigned when upwelling was absent and a value ranging from a to 1.0 when upwelling was present depending upon the substrate class suitability.The latter values are identical to those determined for substrate suitability criteria.The resultant data were plotted as scaled frequency histograms representing the suitability of the combined substrate/upwelling habitat variable function. Statistical Independence of Habitat Variables Evaluated An assumption applied in the development of the suitability criteria ;s 7-4-13 that the habitat variables evaluated act independently in affecting the selection of spawning areas by chum and sockeye salmon.To determine the independence of the habitat variables evaluated in this report,the re1~tionship between utilized depths versus velocities,utilized depths versus substrates,and utilized velocities versus substrates were evaluated.It was not possible to evaluate the relationship of utilized depths,velocities,and substrates to upwelling due to the limited nature of the upwelling data.However,because upwelling criteria were assigned using a binary approach,independence is not necessary. The independence of habitat vari ab 1es evaluated were determi ned by constructing plots of utilized depths versus ve1ocites,utilized depths versus substrates,and utilized ve10cites versus substrates for each species.The degree of correlation between each of these habitat variables was evaluated by determining the coefficient of linear correlation (r)for each relationship.Pruitt (1982)suggest that r values which are less than or equal to an absolute value of 0.2 do not cause significant interdependence of habitat variables to effect WUA analysis.Accordingly,the calculated r values were evaluated in terms of the following hypothesis: Ho :r=10.21 Ha :r>jO.21 The test statistic evaluated is that suggested by Snedecor and Cochran (1980): Zd =IZo-zhr l-/Y'1i"=3 where, Zd =standard normal deviate Zo =1 (ln (1 +r)-1n (1 -r)) Zh =t (In (1 +0.2)-1n (1-0.2)) =0.20273 n =sample size The standard normal deviate was then compared to standard statistical tables to determine probability values to evaluate the test hypothesis. Note that only large positive values of the standard normal deviate can lead to rejection of the null hypothesis due to the defining of Zd as an absolute value. 4.3 Results 4.3.1 Chum Salmon A total of 333 chum salmon redds were sampled during 1982 and 1983 for the habitat variables depth,velocity,substrate,and presence of upwelling groundwater (Table 7-4-4).Of this total,131 were within the hydraulic simulation modelling study sites and had associated 7 4-14 - - Table 7-4-4.Number of measurements made at chum salmon redds in sloughs and side channels of the middle Susitna River,1982 and 1983. Number of Redds 1982 Number of Redds 1983 Total Within Outside Within Outside Within Modeling Modeling Mod eli ng Modeling Modeling Total Site RM Site Site Site Site Site Slough 8A 125.3 36 15 52 Slough 9 126.3 45 31 76 76 Fourth of July Creek 131.0 -mouth 28 28 Slough 9A 133.3 24 24 Slough 11 135.3 15 19 34 Upper Side Channel 11 136.2 2 2 Indian River 138.6 -mouth 3 3 Slough 17 138.9 6 6 Slough 20 140.1 11 11 Side Channel 21 140.6 2 2 2 Slough 21 141.1 33 19 30 52 83 Slough 22 144.3 12 12 Totals 79 52 52 150 131 333 7-4-15 availability data.Because of the limited number of measurements in Side Slough 8A and Side Channel 21,only utilization (128 measurements) and availability data obtained in Side Sloughs 9 and 21 were used in the evaluation of preference.Raw field data are presented in Appendix 7-8-1.The derivation of the suitability criteria for chum salmon spawning for the habitat variables depth,velocity,substrate, upwelling,and a combined substrate/upwelling criteria index for use in the habitat simulation model are presented below by habitat variable. 4.3.1.1 Depth Spawning Suitability Critera The first step in the analysis of field data to develop depth suitability criteria for chum salmon spawning was to select a best depth utilization curve.Depth measurements at 333 chum salmon redds were grouped into six incremental groupings and plotted as histograms (Figure 7-4-2).Table 7-4-5 summarizes the statistics used to determine the llbest ll utilization curve from the six histograms.The histogram with the minimal variance is the histogram labelled A (see Appendix Table 7-C-1).However,histogram A had large indices of irregular fluctuations,and therefore was not selected as the best curve. Histograms B through F were not distinguishable in terms of the minimal variance criteria,however,the minimal irregular fluctuation criterion indicated that histograms C,D,and F had lower indices of irregular fluctuations than Histogram B.Of these three histograms,histogram F had the lowest di sti ngui shab 1e peakedness index and was chosen as the best depth utilization curve (Figure 7-4-3).Histogram F also had grouped mean and vari ance values whi ch compared favorably with the original non-grouped values (Appendix Table 7-C-2). The next step in the development of the depth spawning suitability criteria was to evaluate the best depth util ization curve in terms of depth availability data (i.e.,evaluate preference)and the professional opinion of project biologists familar with middle Susitna River chum salmon stocks.A plot comparing available depths to utilized depths for the subset of utilization data having availability data (Figure 7-4-4) reveals that depths less than 0.2 ft,although available,were not used for spawning.For this reason,depths less than 0.2 ft were assigned a suitability index value of 0.0.The plot also reveals a strong preference for depths between 0.8 and 2.3 ft;that is,the frequency of utilized is greater than the frequency of available.For this reason, these depths were assigned a suitability index value of 1.0.From a consideration of published data (Hale 1981)and the opinion of project biologists familiar with chum salmon in the middle Susitna River,it was decided that depth alone,if greater than 2.3 ft,would not likely limit chum salmon spawning within the range of conditions encountered in the study sites.The maximum predicted depth at all modelled study sites was 7.5 ft at Side Channel 21 at 1,500 cfs.Consequently,the suitability index value of 1.0,assigned to the depths from 0.8 to 2.3 ft,was extended out to 8.0 ft.For the depths from 0.8 to 2.3 ft,the plot revealed a relatively smaller ratio of utilized to available for the depth increment of 0.2 to 0.5 ft tha.n for the 0.5 to 0.8 ft increment.Therefore,it was assumed that the suitability of depth for 7-4-16 - - A INCREMENT I INCREIl'ENT 2 1.0 INTERVAL X~O.I 1.0 INTERVAL 0<a~0.2 0.9 0.9 M X 0.8 0.8 I lJJ i 0 0.7 0.7 !~0.6 0.6 Z 0 0.5 0.5 I-«0.4 0.4 ~0.3 0.3:::! I-0.2=> 0.1 0.1 0.0 0.0 0 1.0 2.0 3.0 4.0 5.0 0 1.0 2.0 3.0 4.0 5.0 DEPTH (ft 1 DEPTH (ft ) C INCREMENT 2 D INCREMENT 3 1.0 1.0 INTERVAL O<a~O.llINTERVAL0.I<a~0.3 0.9 0.9 X 0.8 0.8 lJJ 0 0.7 0.7 Z 0.6 0.6 Z 0 0.5 0.5 ~0.4 0.4« N :::i 0.3 0.3 I-0.2 0.2=> 0.1 0.1 0.0 0.0 0 1.0 2.0 3.0 4.0 5.0 0 1.0 2.0 3.0 4.0 5.0 DEPTH (ft )DE PTH (ft INCREMENT II INTERVAL 0.1<as.0.4 INCREMENT 3 INTERVAL 0.2<a~0.5 5.04.01.0 2.0 3.0 DEPTH (ft) F 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0 05.04.01.0 2.0 3.0 DEPTH (ft) E 1.0 0.9 X 0.8 lJJ 0 0.7Z 0.6 Z 0 0.5 ~0.4 N ::::i 0.3 ~0.2=> 0.1 0.0 0 Figure 7-4-2.Incremental plots of chum salmon spawning depth utilization data. 7-4-17 Table 7-4-5.Summary of statistics on various incremental groupings for chum salmon utilization depth histqgrams. 7-4-18 ~, .... ---I-~••-..-:.j ~----.::J ---] Figure 7-4-3.Best depth utilization curve for chum salmon spawning. CHUM SALMON UTILIZATION VS.AVAILABILITY DEPTH 8.07.06.03.0 4.0 5.0 DEPTH (FT) 2.01.0 -r-r--- -I---r-UTILIZATION~-I - -AVAILABILITY -I l-~i I-I I ",",- ~- I )- 1-- ,.- -~~1--1-- I !D I I I I0, o .1 .6 .8 .2 .9 .4 .5 .3 .7 1.0 >- <.) Zw ::>owu: l.1.. o W ..J« <.) en -....J I.po I No Figure 7-4-4.Depth utilization versus availability for chum salmon spawning used to evaluate preference. )J l )I ,~)J 1 I I'>..~)J l I I ~ for spawning increased in an exponential fashion over the range of 0.2 to 0.8 ft.This was reflected by assigning a suitability index value of 0.2 to a depth of 0.5 ft. The resultant depth suitabil ity curve and criteria for chum salmon spawning are presented in Figure 7~4-5. 4.3.1.2 Velocity Spawning Suitability Criteria The first step in the analysis of field data to develop velocity suitability criteria for chum salmon spawning was to select a best utilization curve.Velocity measurements at 333 chum -salmon redds were grouped into seven incremental groupings and plotted as histograms (Figure 7-4-6).Table 7-4-6 summarizes the statistics used to determine the "best"utilization curve from these seven histograms.The histogram with the minimal variance curve is the histogram labelled A (see Appendix Table 7-C-3).Histogram Bls variance was statistically larger than hi stogram AIS vari ance,but it was smaller than the other six curves.Histograms C and D both had variances which were significantly smaller than histogram GiS.Histograms A and B both had large indices of irregular fluctuations,and accordingly could not be chosen as the best curve.There were no clear alternatives between histograms C through F using the minimal variance criteria (note that curve G had a statistically large variance).Of these three histograms,histogram F had minimal indices of irregular fluctuations and the minimal distinguishable peakedness index and accordingly was chosen as the best velocity utilization curve for chum salmon spawning (Figure 7-4-7). Histogram F also had grouped mean and variance values which compared favorably with the original grouped values (Appendix Table 7-C-2). The next step in the development of the velocity suitability criteria was to assess the best utilization curve in light of availability data (i .e.,evaluate preference)and the professional opinion of project biologists familiar with middle Susitna River chum salmon stocks.A plot comparing available and utilized velocities for the subset of utilized data having availability data (Figure 7-4-8)reveals that a general preference was exhibited for velocities between 0.0 and 1.3 ft/sec.For this reason,a suitability index value of 1.0 was assigned to this range of velocities.Because no concurrent utilization/availability data were collected for velocities exceeding 1.3 ftjsec,suitability for higher velocities were subjectively determined.Since the maximum utilized velocity measured was 4.3 ftjsec (Appendix Table 7-B-1),a velocity of 4.5 ftjsec was chosen as an endpoint and assigned a suitability index value of 0.0.Comparatively greater utilization occurred between 1.3 ftjsec and 2.8 ft/sec compared to utilization recorded for the range from 2.8 and 4.5 ft/sec. Therefore,a higher suitability was assigned to this lower velocity range than for the higher velocity range.This was reflected by assigning a suitability index value of 0.2 to a velocity of 2.8 ftjsec. The resultant velocity suitability curve and criteria for chum salmon spawning are presented in Figure 7-4-9. 7-4-21 CHUM SALMON SUITABILITY CRITERIA CURVE DEPTH SUITABILITY CRITERIA 1.0 .9 .8 X w .70 z-.6'-l >-I I- .t;:. .5 I -N .-J N CO .4«I--.3::J U> .2 .1 O. 0 1.0 2.0 3.0 4.0 5.0 DEPTH (FT) DEPTH 00 0.2 0.5 0.8 80 6.0 SUITABILITY INDEX 00 0.0 02 1.0 1.0 7.0 8.0 Figure 7-4-5.Depth suitability curve for chum salmon spawning. .J J .J J .1 I !I ~J I ).~):1 1 INCREMENT I (15.11 INTERVAL O.l<x~O.z.1.0 0.' ~0.8 ~·0.7 ;0.6 goO., I- et 0.4 N ~0.3 ~O.2. 0.1 o. A 1.0 2.0 1...4.0 '.0 B1.0 0.' 0.8 0.7 0,8 0.' 0.4 0.5 0.' 0.1 0.0 0 1.0 lUI JIlICREMENT I (1.:0) INT'ERYAt.o(I ~0.1 '.0 5.0 VELOCITY (fll..e)VELOCITY (fll..e) INCA£M£NT 2 INTERVAL 0<_",,0.2 INCREMENT 2 I NTEA VAa..u.l<aS.,).~ '.0'.0'.02.0 o 1.0 0.' 0.8 0.7 0 .• '.0'.0'.02.0 C I." Ff i I VELOCITY (ftl.ee)VELOCITY (ft I.ee) INCREMENT :!l INTEfilVAL lJ.1<..0(0.4 rr : I 1.0 0.' ~0 .• ~0.7 Z o.e 2:(;.5 I- <[0.4 N .::J 0.3 ~0.2 0.1 E INCRE'f.ENT 3 INTERVAL 0<'KS-lJ.3 ""0.' 0.8 0.7 oa F 1-0 50 '.0 '.0 VELOCITY (fllsee) I NCRENE~IT 3 INTERVAL iJ.2<1IS,u..! 2.0 3.0 '.0 '0 VELOCITY (ftlsee) Figure 7-4-6.Incremental plots of chum salmon spawning velocity utilization data. -7-4-23 7-4-24 - "'" - ...... -} -....J I ..p. I N U1 1 ~ CHUM SALMON BEST UTILIZATION CURVE VELOCITY 1.0 .9 .8 Xw .7 0 z .6 z o .5 t- <lN .4 -.J-.3t- ::::> .2 .1 0-. . 0 1.0 2.0 3.0 4.0 5.0 VELOCITY (FT/SEC) ---1 ---.-l --~] Figure 7-4-7.Best velocity utilization curve for chum salmon spawning. CHUM SALMON UTILIZATION VS.AVAILABILITY VELOCITY 1.0..,-- "-l I +::> N 0"> .9- 8- >-u .7 -iZ W ::>.6-0wa:.5-lL. 0 .4-w -J II I-----«.3-u C1) 2~r".1 r-- 0 ---. 0 1.0 2.0 3.0 4.0 VELOCITY (FT/SEC) ---UTILIZATION - -AVAILABILITY I 5.0 Figure 7-4-8.Velocity utilization versus availability for chum salmon spawning used to evaluate preference. J i I t •1 I J )J .l )t I 1 ~I 1 1 1 ~-~=-1 L_ j ~~----]---~ CHUM SALMON SUITABILITY CRITERIA CURVE VELOCITY 1.0 1.0 0.2 0.0 VELOCITY 0.0 1.3 2.8 4.5 SUITABILITY CRITERIA SUITABILITY INDEX 1.0 2.0 3.0·4.0 5.0 VELOCITY (FT/SEC) 1.0 .9 .8 xw .70z .6- >- t-.5- ....J-m .4<i" I- .3 I - +=- ::) N (f)" .2 .1 O. 0 Figure 7·4-9.Velocity suitability curve for chum salmon spawning. 4.3.1.3 Substrate Spawning Suitability Criteria The first step in the analysis of field data to develop substrate suitability criteria for chum salmon spawning was to construct a plot of utilized substrates (Figure 7-4-10).Incremental plots of substrate are not appropri ate because substrate data is not conti nuous.Therefore, the utilization data plot was treated as the best substrate utilization curve. The next step in the development of the substrate suitability criteria was to assess the substrate utilization curve in ten11S of availability data (i.e.,evaluate preference)and the professional opinion of project biologists familiar with middle Susitna River chum salmon stocks.As previously stated in the methods section,substrate utilization data were collected at a lower level of resolution than substrate availability data.For this reason,substrate availability data were grouped in order to evaluate preference (Table 7-4-3).However,when assigning suitability index values to substrate data for use in the habitat simulation model,the higher level of resolution was once again used. A plot comparing utilized to available substrates for the subset of utilized data for which availability data exists (Figure 7-4-11)reveals that substrates ranging from large gravel to cobble appear to be preferred for spawning.However,a review of literature data (Hale 1981;Wilson et ale 1981)reveals that cobble ~ubstrates are a less preferred substrate for chum salmon spawning than are large gravels and rubbles.Furthermore,based on discussions with field personnel,there is a strong likelihood of a sampling bias for larger substrates since field personnel more likely overestimated substrate sizes.For these reasons,a suitability index value of 1.0 was assigned to substrate size classes 7 through 9 (corresponding to large gravel and rubble substrates)and suitability index values of 0.85 and 0.70 were assigned to substrate size classes of 10 and 11 (corresponding to large rubbles and small cobbles),respectively,based on assumptions concerning the sUitability of cobble as a spawning substrate.The largest two substrate size classes,12 (large cobbles)and 13 (boulders),were assigned index values of 0.25 and 0.0,respectively,after taking the noted sampling bias into account. The suitability indices for the smaller substrate size classes (1 through 6)were assigned as follows.Based on the lack of utilization in the substrate size classes 1 and 2 (silt),a suitability index value of 0.0 was assigned to these substrate classes.The small ratio of utilized to available for substrate size classes 3 and 4 (sand),in addition to literature information showing little preference for this substrate class (Hale 1981;Wilson et al.1981)resulted in low suitability index values (0.025 and 0.05,respectively)being assigned to these substrate size classes.Suitability "index values for the substrates size classes 5 and 6 were assigned by assuming a linearly increasing suitability of substrates between size classes 4 and 7. The resultant substrate suitability curve and criteria developed for chum salmon spawning are presented in Figure 7-4-12. 7-4-28 -, ~, - - - - 1 ]--~~--=l ~-=~-~ CHUM SALMON UTILIZATION CURVE SUBSTRATE ____-=:J LO l.9 .8 Ix.7w ""'-J 0 I Z-I::>.6I- N l.O Z 0 .5-I-«.4N--.J-.3I- ::> .2 .1 0 I '2 3 4 5 6 7 SI SA SG LG SUBSTRATE 8 9 RU CODE •10 II 12·13 CO 80 SUBSTRATE PARTICLE CODE SIZE I SI SILT 2 3 SA SAND 4 5 SG 1/8 _I" 6 7 LG 1_3" 8 9 RU 3-9" 10 II CO 5_10" 12 13 BO >10" Figure 7-4-10.Substrate utilization curve for chum salmon spawning. CHUM SALMON UTILIZATION VS.AVAILABILITY SUBSTRATE UTILIZATION - -AVAILABILITY SUBSTRATE PARTICLE CODE SIZE I SI SILT 2 . 3 SA SAND 4 5 SG 1/8 -I" 6 7 LG 1-3" 8 9 RU 3-9" 10 II CO 5-10" 12 13 BO >10" I 2 3 4 5 6 7 8 9 10 II 12 13 SI SA SG LG RU CO 80 SUBSTRATE CODE - r-., I I- -I I I I-I I:-I II--- I-I -I I I-1---I rl HI 1.0 .9 >-.8 0z .7w ::> a .6 w ~.5 '-I I.L I ..f::> 0 I W .4w 0 ...J <t .30 CJ) .2 .1 0 Figure 7-4-11.Substrate utilization versus availability for chum salmon spawning used to evaluate preference. J .1 )J I !I !..~)I J J J I J l .~ .~ J --1 --~-=1 ~---J -----3 CHUM SALMON SUITABILITY CRITERIA CURVE SUBSTRATE 1.0 .9 .8 X w .70z-.6 -....J >- I ~.5.j:::o -I --Jw-......m <:(.4 ~ ::>.3 (J) .2 .1 0 I 2 3 4 5 6 7 SI SA SG LG SUBSTRATE 8 9 RU CODE -.-- 10 II 12 13 CO BO SUITABILITY CRITERIA SUBSTRATE PARTICLE SUITABILITY CODE SIZE INDEX I SI SILT 0.00 2 0.00 3 SA SAND 0025 4 0.05 5 SG 1/8 -I"0.20 6 0.60 7 LG 1_3"1.00 8 1.00 9 RU 3-9"100 10 0.85 II CO 5-10"0.70 12 0.25 13 BO >10"000 Figure 7-4-12.Substrate suitability curve for chum salmon spawning. __t 4.3.1.4 Upwelling Spawning Suitability Criteria Suitability criteria for upwelling were assigned using a binary approach (see methods sections);that is,a suitability index of 1.0 was assigned to upwelling present and a suitability index of 0.0 to upwelling absent. This approach seems justified based on accumulated field data indicating that spawning chum salmon appear to key on upwelling (ADF&G 1983b). 4.3.1.5 Combined Substrate/Upwelling Spawning SUitability Criteria The combined substrate/upwelling suitability criteria developed for use in the"habitat simulation model are identical to the individual substrate suitabil ity criteri a when upwell ing is present except that when upwelling is not present y a suitability index value of 0.0 is assigned to each substrate class.Table 7-4-7 is a tabulation of the development of the suitability index for this combined habitat variable. The resultant suitability curve and criteria developed for the combined substrate/upwelling variable for chum salmon spawning are presented in Figure 7-4-13. 4.3.1.6 Statistical Independence of Habitat Variables Evaluated Plots depicting the relationship between utilized depths versus velocities,utilized depths versus substrates,and utilized velocities versus substrates for the chum salmon spawning utilization data are depicted in Figure 7-4-14.Included on each plot are the number of measurements and the coefficient of linear correlation (r)computed for each relationship.Computed r values and their derived statistics (Appendix Table 7-C-4)indicate that an acceptable level of independence as define by Pruitt (1982)occurs among these habitat variables. 4.3.2 Sockeye Salmon A total of 81 sockeye salmon redds were sampled during 1982 and 1983 for depth,velocity,substrate,and presence of upwelling groundwater (Table 7-4-8).Of this total,one was located within a hydraulic simulation modelling study site.For this reason,an analysis of preference could not be conducted on the sockeye salmon spawni ng util i zati on data base. Thus,the derived sockeye salmon spawning suitability criteria are based solely on the utilization data base as modified by the professional opinion of project biologists familiar with middle Susitna River sockeye salmon stocks using literature data and accumulated field observations. The raw field data are presented in Appendix 7-8-3.The derivation of the sockeye salmon spawni ng suitabil ity criteri a for each of these habitat variables from these raw field data for use in the habitat simulation model are presented below by habitat variable. 4.3.2.1 Depth Spawning Suitability Criteria The first step in the analysis of field data to develop depth 7-4-32 - 1 ~----J ----=--1---1 .-----1 _---l 1 Table 7-4-7.Data used to develop combined (substrate and upwelling)suitability curve for chum salmon. Description Code Weighting Factor Combined Factor Substrate ..!I Upwe 11 i ng 'l:./Substrate Upwell ing Substrate Upwell i ng Code Suitability Index SI A 1 a 0.00 0.00 1.0 0.00 SI P 1 1 0.00 1.00 1.1 0.00 SI/SA A 2 a 0.00 0.00 2.0 0.00 SI/SA P 2 1 0.00 1.00 2.1 0.00 .......,SA A 3 a 0.025 0.00 3.0 0.00 I SA P 3 1 0.025 1.00 3.1 0.025.+:0 I SA/SG A 4 a 0.05 0.00 4.0 0.00·w ·w SA/SG P 4 1 0.05 1.00 4.1 0.05 SG A 5 a 0.20 0.00 5.0 0.00 SG P 5 1 0.20 1.00 5.1 0.20 SG/LG A 6 a 0.60 0.00 6.0 0.00 SG/LG P 6 1 0.60 1.00 6.1 0.60 LG A 7 a 1.00 0.00 7.0 0.00 LG P 7 1 1.00 1.00 7.1 1.00 LG/RU A 8 a 1.00 0.00 8.0 0.00 LG/RU P 8 1 1.00 1.00 8.1 1.00 RU A 9 a 1.00 0.00 9.0 0.00 RU P 9 1 1.00 1.00 9.1 1.00 RU/CO A 10 a 0.85 0.00 10.0 0.00 RU/CO P 10 1 0.85 1.00 10.1 0.85 CO A 11 a 0.70 0.00 11.0 0.00 CO P 11 1 0.70 1.00 11.1 0.70 CO/BO A 12 a 0.25 0.00 12.0 0.00 CO/BO P 12 1 0.25 1.00 12.1 0.25 BO A 13 a 0.00 0.00 13.0 0.00 BO P 13 1 0.00 1.00 13.1 0.00 1/SI -Silt,SA -Sand,SG -Small Gravel,LG -Large Gravel,RU -Rubble,Co -Cobble,SO -Boulder 'l:./A -Absent,P -Present CHUM SALMON COMBINED SUITABILITY CRITERIA CURVE SUBSTRATE /UPWELLING 1.0 I 2DT3DT4'O~oT&oTloTa6T9~OTio.0 liLa [,'2'.0 !13'.6T 1.1 21 31 4.1 5.\6.1 7.1 81 9.\10.1 11.1 12.1 13.1 COMBINED SUBSTRATE /UPWELLING CODE I III ~I I SUITABILITY CRITERIA SUITABILITY COPE INDEX 1.0 0.00 1.1 0.00 2.0 0.00 2.\0.00 30 0.00 3.1 0025 4.0 0.00 4.1 0.05 5.0 0.00 5.1 0.20 60 0.00 6.1 0.60 7.0 0.00 7.1 1.00 8.0 000 8.1 1.00 9.0 0.00 9.1 1.00 10.0 0.00 10.1 0.85 11.0 0.00 II.I 0.70 12.0 0.00 12.1 0.25 13.0 0.00 13.1 0.00 Figure 7-4-13.Combined substrate/upwelling suitability curve for chum salmon spawning. J J ••J ....1 I I I I I .J J i I J )I J i 5 4 (J '"V1 3"-1; /: (j 2a..J '"> o o 00 CHUM SALMON o o o 0 o n'333 r •-0.21 'i I 0 00 0 2 DEPTH (FT) 14 13 00 0 0 0 0 12 11 lDC aJ:DIIII3 a::a:D1:IIIIJ C C C C []00 10 '"Q 9 C !iii CIIIIII:IC[JJ C 0 0a {J w a ~ '"7 t:Ilc:J::IID:IIIOOlIDaaDOIllCO IDO 0>- V1 In 6.:::J V1 5 00 CD D eoce 0 0 4 3 0 0 0 0 0 2 a 2 DEPTH (FT) 4 n .319 r •-O.O!! 4 2 4 VELOCITY (FTjSEC) 1 I ..,. I 13 ..0 00 12 11 ..-am:IDO 10 '"'"9a {J '"B>-« '"7>-V1 In 6:::J V1 5 pam 0 00 4 3 0 0 0 2 0 o co c cmc c:::J 1:1 [] o o o o o n'3/9 r •-0.08 o Figure 7-4-14.Plots depicting the relationship between utilized depths versus velociti~s,utilized depths versus substrates.and utilized velocities versus substrates for chum salmon spawning. 7-4-35 Table 7-4-8.Number of measurements made at sockeye salmon redds in sloughs and side channels of the middle Susitna River, 1982 and 1983. 7-4-36 ~- - - - - '1 .I 1'"1'" I .,.. I "'"' suitability criteria for sockeye salmon spawning was to select a best depth utilization curve.Depth measurements at 81 sockeye salmon redds were grouped into six incremental groupings and plotted as histograms (Figure 7-4-15).Table 7-4-9 summarizes the statistics used to determine the IIbest"utilization curve from the six histograms.The histogram with the minimal variance curve is the histogram labelled A (see Appendix Table 7-C-5).However,histogram A had large indices of irregular fluctuations and therefore was not chosen as the "best ll curve. Histograms B through F were not distinguishable in terms of the minimal variance criteria,however,the minimal irregular fluctuation criteria indicated that histograms D,E,and F had lower values of irregular fl uctuati on than hi stogram B.Of these three hi stograms,hi stogram E had the lowest di sti nguishable peakedness index and was accordi ngly chosen as the "bestfl utilization curve (Figure 7-4-16).Histogram E also compared favorably with the grouped data in terms of sample mean and standard deviation (Appendix Table 7-C-6). The next step in the development of the depth spawni ng suitabil ity criteria was to evaluate the best depth utilization curve in terms of professional judgment using published data and the opinion of project biologists familiar with middle Susitna River sockeye salmon stocks.No evaluation of preference could be made due to the lack of concurrent availability data collection. Depths ranging from 0.0 to 0.2 ft were not utilized for spawning and were therefore assigned a suitability index value of 0.0.Based on utilization patterns depicted in Figures 7-4-15 and 7-4-16,depths centering around 0.75 ft appear to be most often utilized.For this reason,a suitability index value of 1.0 was assigned to a depth of 0.75 ft.Based on the opinion of project biologists that depth alone,if greater than 0.75 ft,would not likely l-imit sockeye salmon spawning within the range of conditions in the study sites (i .e.,the maximum predicted depth at a study site was 7.5 ft in Side Channel 21 at 1,500 cfs),the suitability index value of 1.0 was extended out to 8.0 ft.It was felt that depths ranging from 0.2 to 0.5 ft would be less suitable for spawning than depths ranging from 0.5 to 0.75 ft.For this reason, a lower su itabi 1ity was ass i gned to the lower depth range than was assigned to the higher depth range.This was reflected by assigning a suitability index value of 0.9 to a depth of 0.5 ft . The resultant depth suitability curve and criteria for sockeye salmon spawning is presented in Figure 7-4-17. 4.3.2.2 Velocity Spawning Suitability Criteria The first step in the analysis of field data to develop the velocity suitability criteria for sockeye salmon spawning was to select a best velocity util ization curve.Velocity measurements at sockeye salmon redds were grouped into seven incremental groupings and plotted as histograms (Figure 7-4-18).Table 7-4-10 summarizes the statistics used to select the "best ll utilization curve from the seven histograms.The seven histograms were not distinguishable in terms of the minimal 7-4-37 INCREMENT I INTERVAL X~O.X ~0.1 A 1.0 O. X W Q ~ Z 0 ~ N :J;: ;:) 0.1 0.0 1.0 2.0 3.0 4.0 O. B 1.0 2.0 INCREMENT 2 INTERVAL.0 ~.~0.2 4.0 ~, DEPTH (ft) C D 1.0 INCRI!III!IlT 2 1.0 0.'INTI!RYAL 0.1<>~0.3 0.11 X 0 ..0.-W Q o.r fU~ Z 0 ..o. 0 0.5 0.5~0...0 •• N :J 0.3 '0.11 i=0.1 0..;:) 0.1 0.1 0.0 0.0 LO ZJ)3.0 4.0 s.o DEPTH (tt) DE PTH (ttl INCRI!III!NT 3 I NTI!IlYAL 0<>So 0.3 •.0 z.o !.O 4.0 s.o DEPTH (ft) lNCRl!lIEIlT I IIlTI!RYAL 0.1<•.s0.41.0 0.. ~0.' ~o.r z 0.' Q 0.5 ~NO•• :J 0.1 i=;:)0.2 0.1 0.0 E 1.0 ZJ)!.O DEPTH (H) 50 1.0 0.' o.r 0.' 0.5 0•• 0.3 0.2 0.1 0.0 F 1.11 INCREIII!NT 3 IIlTERYAL 0.2 <•.s0.5 z.o 3D DEPTH (ft) 5.0 - - Figure 7-4-15.Incremental plots of sockeye salmon spawning depth utilization data. 7-4-38 - ""'1' I I Table 7-4-9.Summary of statistics on various incremental groupings for sockeye salmon utilization depth histograms. HISTOGRAM LABEL INCREMENT SIZE INCREMENT START A 0.1 0.0 B 0.2 0.0 C 0.2 0.1 o 0.3 0.0 E 0.3 0.1 F 0.3 0.2 VARIANCE OF 8.5 29.1 29.4 63.9 61.4 53.8 FREQUENCY COUNTS 'i COEFFICIENT OF VARIATION OF FREQUENCY COUNTS 0.97 0.93 0.94 0.99 0.97 0.81 I"'f IRREGULAR : I FLUCTUATIONS Magnitude 16 8 4 1 1 3 Number 8 3 2 1 1 2 Mean 2.00 2.67 2.00 1.00 1.00 1.50 Maximum 3 6 3 1 1 2 PEAKEDNESS 0.25 0.42 0.59 0.67 0.33 0.58 -7-4··39 1.0 .9 .8 x .7w 0 ........Z .6 I - -l::>ZI -l::>0 .50-I-«.4N----J-.3I- :::> .2 .1 0 0 1.0 2.0 SOCKEYE SALMON BEST UTILIZATION CURVE DEPTH r ,--I --I , 3.0 4.0 5.0 6.0 7.0 8.0 DEPTH (FT) Figure 7-4-16.Best depth utilization curve for sockeye salMon spawning. I cl I J -J I I ,.1 J I J I J I J J ]1 SOCKEYE SALMON SUITABILITY CRITERIA CURVE DEPTH j ) 1.0 .9 .8 X w .7 0 SUITABILITY CRITERIAz .6 SUITABILITY ">-DEPTH INDEX I l ..j:::o r-.5 000 0.0-I -.J..j:::o 020 0.0p-m .4 0.30 0.2 <{ l-0.50 0.9-.3 0.75 1.0:::J (f)8.00 1.0 .2 .1 a . . ...a 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 DEPTH (FT) Figure 7-4-17.Depth suitability curve for sockeye salmon spawning. A '.0 0 .• x 0.• '"C>0.7~ 0.'Z 0 0._ i=«0.4 N :::i 0.' j::0.'~ 0.1 0.0 1.0'2..0 '.0 4.0 5.0 B o. 0.1 Q.T... 0 .. C).4 U D.lI 0.1 0.0 LO 4.0 1.0 ""'1 VELOCITY (ftlleel ,.0 a. 0.0 0.7 0.0 o.s o VELOCITY I ft/..~l INCRIII.IfT I ulITllI'VAL 0.1 zSO..5 """ VELOCITY If1l ..~1VELOCITY(ft/••~I ... 0.0 1.0 lUI 4.0 I.G - E INCREMENT!F 1.0 INT!"YAL.Oc.$O.1 I. 0.'O. ><0.''"0.'C> ~0.7 0.7 Z 0.'0..0 0._~o.e«0.4 C).4!i ,j 0.3 U~0.2~D.lI 0.1 0.' 0.0 1.0 '.0 '.0 4.0 _.0 VELOCITY lft/lee) INCREMENT !i INTERVAL 0.1<1 'S.D." 1.0 La 3D ....0 '!II.o VELOCITY Ift/loc) - G'.0 0.. ><0.0 '"Q O.T~ Z ... Q o.s !C OA N :::i 0 •• j::\U:> 0.' 0.0 '.0 2-D INCR ••lfT I I MTCItVAL G.2C ....,s,0.' .Figure 7-4-18. VELOCITY [flluc) Incremental plots of sockeye salmon spawning velocity utilization data. 7-4-42 - - Table 7-4-10.Summary of statistics on various incremental groupings for sockeye salmon velocity utilization histograms. 7-4-43 variance criteria (see Appendix Table 7-C-7).Histograms A and B both had comparatively large indices of irregular fluctuations and could not be chosen as the best curve,whereas hi stograms C through G had no irregular fluctuations.Of these five histograms,histogram F had the minimal distinguishable peakedness index and was selected as the "best" utilization curve (Figure 7-4-19).Histogram F also had grouped mean and variance values which compared favorably with values for the non-grouped data (Appendix Table 7-C-6). The next step in the development of the velocity spawning suitability criteria was to evaluate the best velocity utilization curve in terms of professional judgment using previously published data and the opinion of project biologists familiar with middle Susitna River sockeye salmon stocks.No evaluation of preference could be made due to the lack of concurrent availability data collection. Based on the best velocity utilization curve,a suitability index value of 1.0 was assigned to a velocity of 0.0 ft/sec.Based on a review of literature data (USFWS 1983)and the opinion of project biologists,the suitabil ity index value of 1.0 was extended out to a velocity of 1.0 ft/sec.A suitability index value of 0.0 was assigned to a velocity of 4.5 ft/sec as it was decided to establish the endpoint of the curve to be the same as the chum salmon curve.This was done because it was felt that velocities for sockeye salmon spawning could be no greater than for chum salmon spawning and that there was no data base to support lower velocities as an end point.Because it was felt that velocities ranging from 1.0 to 3.0 ft/sec would be more suitable for sockeye salmon spawning than velocities from 3.0 to 4.5 ft/sec,the lower range of velocities were assigned a higher suitability than were the higher range.This was reflected by assigning a suitability index value of 0.10 to a velocity of 3.0 ft/sec. The resultant velocity suitability curve and criteria for sockeye and salmon spawning are presented in Figu~e 7-4-20. 4.3.2.3 Substrate Spawning Suitability Criteria The first step in the analysis of field data to develop substrate suitability criteria for sockeye salmon spawning was to construct a plot of utilized substrates (Figure 7-4-21).Incremental plots of substrate are not appropriate because substrate data is not continuous. Therefore,the substrate utilization data plot was treated as the best substrate utilization curve. The next step in the development of the substrate spawning suitability criteria was to evaluate the substrate utilization curve in terms of professional judgment using literature data and the opinion of project biologists familar with middle Susitna River sockeye salmon stocks.No evaluation of preference could be made due to the lack of concurrent availability data collection. As previously stated in the methods section,substrate utilization data were collected at a lower level of precision than substrate data 7-4-44 - - "'"', - ~, - I ] SOCKEYE SALMON BEST UTILIZATION CURVE VELOCITY 3 ::> ...... I ~ I ~ U1 .2 .1 5.01.0 2.0 3.0 4.0 VELOCITY (FT/SEC) o f"Ii:':'''''i"I'':''':':':':''':::::::::'::::\I I I I o Figure 7-4-19.Best velocity utilization curve for sockeye salmon spawning. SOCKEYE SALMON. SUITABILITY CRITERIA CURVE VELOCITY SUfTABI U TV CRITERIA '-J I .j:::. I .j:::. Q') 1.0 .9 .8 Xw .70 z- >- .6 l--.5 -.J- OJ«.4 l--::>.3 (f) .2 .1 0 0 .1.0 2.0 3.0 4.0 5.0 VELOCITY (Fl/SEC) VELOCITY 0.0 1.0 2.0 3.0 4.5 SUITABILITY INDEX 1.0 1.0 0.5 0.1 0.0 Figure 7-4-20.Velocity suitability curve for sockeye salmon spawning. J J J J i I :I1\1 I I J )J _J 1 I I --1 ._~ SOCKEYE SALMON UTILIZATION CURVE SUBSTRATE ] 1.0 .9 .8 Xw .7 0 z .6 "-J z I 0 .5+::>-I t-+::> "-J <l N .4 --J t-.3 ::> .2 .1 a I 2 3 4 5 6 7 8 9 \0 II 12 13 SI SA SG LG RU CO 80 SUBSTRATE CODE SUBSTRATE PARTICLE CODE SIZE 1 SI SILT 2 3 SA SAND 4 5 SG 1/8 -I" 6 7 LG 1-311 8 9 RU 3-9" 10 II CO 5 -lO" 12 13 80 >1011 Figure 7-4-21.Substrate utilization curve for sockeye salmon spawning. collected for input into the hydraulic simulation model.For this reason,the higher level precision was used when assigning suitability criteria for substrate (Table 7-4-3).However,when assigning suitability -index values to substrate data for use in the habitat simulation model,the lower level of precision was once again used. The plot of utilized substrates reveals that large gravel and rubble substrates appear to be most often utilized for sockeye salmon spawning. Because this agrees with literature information (USFWS 1983),these substrates (classes 7,8,and 9)were assigned a suitability index value of 1.0.Further analysis of the utilization plot reveals that cobble (substrate classes 11 and 12)and boulder (substrate class 13) substrates were also utilized for spawning but to a lesser extent than were large gravels and rubbles.It was felt,however,that the apparent uti 1izati on of the 1arger substrate si ze cl asses was based more on a sampling bias toward larger substrates than smaller substrates;that is, field personnel more likely noted larger substrate sizes than smaller substrate sizes.This combined with information available in the literature (USFWS 1983)which show that cobble and boulder substrates are not as preferred a substrate as large gravels and rubbles for spawning lead to substrate class 10 (large rubbles)being assigned a suitability index value of 0.90,substrate class 11 (small cobbles)a value of 0.25,and substrate class 12 (large cobbles)a value of index 0.10.Substrate cl ass 13 (boul der)was ass i gned a suitabil ity index value of 0.0 based on the noted sampling -bias and the judgment that substrates consisting of only boulders would not be suitable for spawning. The plot of utilized substrates also reveals no utilization of silt (substrate classes 1 and 2)substrates and only limited utilization of sand (substrate classes 3 and 4)substrates for spawning.Based on this and the judgment that pure silt and sand substrates would not be suitable for sockeye salmon spawning,a suitability index value of 0.0 was assi gned to substrates cl asses 1 through 3.The plot also reveals moderate utilization of small gravel substrates (substrate class 4 through 6)for spawning.Based on accumulated field experience and literature information (USFWS 1983),it was felt that the larger substrates in this range would be more suitabl~for spawning than would the smaller substrates.For these reasons,the larger substrates in this range were assigned a higher suitability index value than were the smaller substrates.This was done by assigning a suitability index value of 0.10 to substrate class 4,a value of 0.50 to substrate class 5,and a value of 0.95 to substrate class 6. The resultant substrate suitability curve and criteria for sockeye salmon spawning is presented in Figure 7-4-22. 4.3.2.4 Upwelling Spawning Suitability Criteria Suitability criteria for upwelling were assigned using a binary approach (see methods sections);that is,a suitability index value of 1.0 was assigned to upwelling present and a suitability index value of 0.0 was assigned to upwell ing absent.These assignments were predicated on accumulated field observations which showed that sockeye salmon appeared to key on upwelling for spawning (ADF&G 1983b). 7-4-48 - - - - - I 1 )--1 --1 »]---1 i I 1 J SOCKEYE SALMON SUITABILITY CRITERIA CURVE SUBSTRATE 1.0 .9 .8 X w .7 0z .6- >-r .5 .............J-I CD .4+:> I <t .f::;o rI.D -::J .3 (f) .2 .1 0 I 2 3 4 5 6 7 SI SA SG LG SUBSTRATE 8 9 10 II 12 13 RU CO BO CODE SUITABILITY CRITERIA SUBSTRATE PARTICLE SUITABILITY CODE SIZE INDEX I SI SILT 0.00 2 0.00 3 SA SAND 0.00 4 0.10 5 SG 1/8 -I"0.50 6 ()95 7 LG 1-3"1.00 8 1.00 9 RU 3-9"100 10 0.90 II CO 5 -10"O.25 12 0 10 13 80 >10"0.00 Figure 7-4-22.Substrate suitability curve for sockeye salmon spawning. 4.3.2.5 Combined Substrate/Upwelling Spawning Suitability Criteria The combined substrate/upwelling suitability criteria developed for use in the habitat simulation model are identical to the individual substrate suitabi 1ity criteri a when upwell i ng is present except that when upwelling is not present,a suitability index value of 0.0 is assigned to each substrate class.Table 7-4-11 is a tabulation of the development of the sUitability index for this combined variable.The resultant suitability curve and criteria developed for the combined substrate/upwelling variable for sockeye salmon spawning are presented in Figure 7-4-23. 4.3.2.6 Statistical Independence of Habitat Variables Evaluated Plots depicting the relationship between utilized depths versus ve lociti es,util i zed depths versus substrates,and util i zed velocites versus substrates for the sockeye salmon spawning utilization data are depicted in Figure 7-4-24.Included on each plot are the number of measurements and the coefficient of linear correlation (r)computed for each relationship.Computed r values and their derived statistics (Appendix Table 7-C-4)indicate that an acceptable level of independence as defined by Pruitt (1982)occurrs among these habitat variables. 4.4 DISCUSSION 4.4.1 Assumptions and Limitations of the Data Base The techniques used in the derivation of the habitat suitability criteria presented in this report are an adaptation of those presented in Baldrige and Amos (1982)and Bovee and Cochnauer (1977).Several underlying assumptions are made in developing and applying suitability criteria as they relate to chum and sockeye salmon spawning.These include: 1)Depth,velocity,substrate,and upwelling are the most critical habitat variables affecting the selection of spawning areas by chum and sockeye salmon; 2)These habitat variables are mutually independent;that is, the degree of suitability of a particular level of each habitat variable is not affected by varying levels of the other habitat variables; 3)A sufficiently large random sample was obtained to accurately represent the range of utilized and available habitat conditions found in sloughs and side channels; 7-4-50 p.:m!!, ,~ - .... .... I ---)~~1 .1 I ]--, Table 7-4-11.Data used to develop combined (substrate and upwelling)suitability curve for sockeye salmon. Description Code Weighting Factor Combined Factor Substrate 11 Upwe 11 i ng ?:-I Substrate Upwell ing Substrate Upwell ing Code Weight Factor .SI A 1 0 0.00 0.00 1.0 0.00 SI P 1 1 0.00 1.00 1.1 0.00 SI/SA A 2 0 0.00 0.00 2.0 0.00 SI/SA P 2 1 0.00 1.00 2.1 0.00 SA A 3 0 0.00 0.00 3.0 0.00 '.J SA P 3 1 0.00 1.00 3.1 0.00ISA/SG A 4 0 0.01 0.00 4.0 0.00.p, SA/SG P 4 1 0.01 1.00 4.1 0.10(Jl.....SG A 5 0 0.05 0.00 5.0 0.00 SG P 5 1 0.05 1.00 5.1 0.50 SG/LG A 6 0 0.95 0.00 6.0 0.00 SG/LG P 6 1 0.95 1.00 6.1 0.95 LG A 7 0 1.00 0.00 7.0 0.00 LG P 7 1 1.00 1.00 7.1 1.00 LG/RU A 8 0 1.00 0.00 8.0 0.00 LG/RU P 8 1 1.00 1.00 8.1 1.00 RU A 9 0 -1.00 0.00 9.0 0.00 RU P 9 1 1.00 1.00 9.1 1.00 RU/CO A 10 0 0.90 0.00 10.0 0.00 RU/CO P 10 1 0.90 1.00 10.1 0.90 CO A 11 0 0.25 0.00 11.0 0.00 CO P 11 1 0.25 1.00 11.1 0.25 COIBO A 12 0 0.10 0.00 12.0 0.00 COIBO P 12 1 0.10 1.00 12.1 0.10 BO A 13 0 0.00 0.00 13.0 0.00 BO P 13 1 0.00 1.00 13.1 0.00 11 SI -Silt,SA -Sand,SG -Small Gravel,LG -Large Gravel,RU -Rubble,Co -Cobble,BO -Boulder ?:-I A -Absent,P -Present COMBINED SUBSTRATE /UPWELLING CODE 0.00 000 000 0.00 0.00 0.00 0.00 0.10 0.00 0.50 0.00 0.95 0.00 1.00 0.00 1.00 0.00 1.00 0.00 0.90 0.00 0.25 0.00 0.10 0.00 0.00 SUITABILITY INDEXCODE 1.0 1.1 2.0 2.1 3.0 3.\ 4.0 4.1 5.0 5.1 6.0 6.1 70 7.1 8.0 8.1 9.0 9.! 10.0 10.1 11.0 11.1 12.0 12.1 13.0 13.0 SUITABILITY CRITERIA I I lill illi1jll.!: I 4.0 15.0 16D17oT8~OI-9'.01l~13.OT 4.1 5.1 6.1 7.1 8.1 9.1 10.1 11.1 121 13.1 SOCKEYE SALMON COMBINED SUITABILITY CRITERIA CURVE SUBSTRATE /UPWELLING 1.0 .9 .8 Xw .7 0z .6 -....J >-I t---P .5!- (Jl .-J N -aJ .4<t t---.3:Jen .2 .1 .0 Figure 7-4-23.Combined substrate/upwelling suitability curve for sockeye salmon spawning. I I J I 1 I 1 I I I I J J I I ) SOCKEYE SALMON 0.9 0 n'61 r •-0.28 O.B 0 0.7 0 "u '"In 0.6'-t 0.5 0f0 0 (J OA-a 0 0 ...l W>0.3 0 00 0q, 00 0.2 ""0 0 "'9 00 o 0 0 0.1 0 o 0 ""0 0 80",,0 0 0 0 ~.~ 0 2 4- DEPTH (FT) 14- 13 =0 n'77 12 r •-0.31 11 00 ""0 10 w '"9 C1Cl:JCC IElCIJ:IJJ:I I:J[]C 0a (J ~8 « ll<7 0 o lCllIIIIJ"em 0 co c c co Cf- In II!6:::J In 5 00 00 0 0 4- :3 0 0 2 0 2 4- DEPTH (FT) 14 13 0 0 ""n -61 r •-0.09 12 ;~11 0 """"" 10 w '"9 C "" c "c ""0 (J w 8 ~Ie o::c::m:Jll<7 "C tl 0 0f- In II!6:::J In 5 "0 0 0 4- :3 " 2 0 ".2 OA 0.6 0.8 VElOCITY (FT/SEC) Fi gure 7-4-24.Plots depicting the relationship between util i zed depths versus velocities.util i zed depths versus....substrates,and util i zed vel ociti es versus substrates for sockeye salmon spawning. 7-4-53 5) 4)The suitability of a selected set of habitat variables for spawning is based on an actual preference of a set of habitat variables at a site; Suitability criteria developed.from data collected at representative study site can be assumed to be representative of suitability of habitats in other areas. In the present analysis,it is assumed that the suitability,in terms of spawning habitat at a specific location within a slough or side channel, can be accurately determined if all the variables affecting the behavior of a spawning fish are known.Since this is not likely,we have identified four habitat variables which appear to be the most critical variables for chum and sockeye salmon spawners:depth,velocity, substrate,and the presence of upwelling.Although other habitat variables,notably water quality and temperature,may also potentially affect the suitability of a site for chum and sockeye salmon spawning, they are believed to exert only a limited influence under prevailing conditions. It is questionable,however,whether the four habitat variables evaluated are of equal relative importance as critical habitat variables affecting the selection of spawning areas by chum and sockeye salmon in sloughs and side channels of the middle Susitna River.Assuming passage depth requirements are met,the presence or absence of upwelling appears to be the key habitat variable affecting selection of spawning areas by chum and sockeye salmon.This is especially apparent in slough habitats,where the available depth,velocities,and substrates are often suitabl e for spawni ng,but where spawni ng is only observed to occur in areas of upwelling.It is less apparent in side channels habitats where unsuitable depth,velocity,or substrates may make upwelling areas unusable spawning habitat. The question as to whether these habitat variables act independent of one another in'terms of salmon spawning utilization was addressed by statistically analyzing the relationship between each of these habitat variables.It was not possible to statistically analyze the relationship of utilized depths,velocities,or substrates to upwelling due to the limited nature of the upwelling data.However,because upwelling was assigned using a binary approach,independence is not necessary.Based on computed correlation values and their derived statistics there appears to be an acceptable level of independence,as defined by Pruitt (1982),amoung these habitat variables for both chum or sockeye salmon;that is,they appear to act independent of one another.This analysis does not,however,imply that the habitat variables evaluated are independent as they occur in the studied sloughs and side channels.It merely demonstrates that salmon which spawn in these sites select redd locations which are characterized by depth, velocity,and substrate conditions which appear to be uncorrelated. Although random sampling of the entire spawning population was attempted,portions of the population were undoubtedly overlooked. Turbid water conditions accompanying high flows during spawning periods 7-4-54 ~, - ~l made it difficult to locate active chum and sockeye salmon redds. Because of this,redds in side channel habitats are likely to be underrepresented in the analyses.For this reason,the suitability criteria developed in this chapter may better represent chum and sockeye salmon spawning in sloughs than in side channels of the middle Susitna River.It is our opinion,however,that the suitability criteria developed in this chapter are sufficiently broad to represent chum and sockeye salmon spawning habitat in side channels of the middle Susitna River. The number of utilization measurements obtained within hydraulic simulation modelling study sites where availability data were collected was 1imited by low escapement and low flow conditi ons duri ng 1982 and 1983.Sample sizes,therefore,to analyize preference for a particular habitat variable were limited.This problem was partially circumvented by collecting additional utilization data in areas outside of the availability modelling sites.However,since availability data were not collected in these areas,it could not be determined whether the spawning habitat utilization data collected outside of modelling areas reflect a preference for that habitat variable. In summary,the inherent assumptions used in the development of the sui tabi 1ity criteri a presented in the chapter genera 11y appear justified,although specific assumptions may have been violated under certain circumstances.The extent to which these violations influence our analyses is difficult to evaluate,however,it is believed that such violations exert only a limited influence. 4.4.2 SUitability Criteria 4.4.2.1 Chum Salmon The suitability criteria developed in this section for the habitat variables depth,velocity,substrate,and upwelling represent our best estimation of the suitability of these habitat variables for chum salmon spawning in sloughs and side channels in the middle reach of the Susitna River where spawni ng currently occurs.The criteri a are based on an evaluation of utilization of these habitat variables as modified using an evaluation of preference and professional judgment based on literature information and the opinion of project biologists familiar with middle Susitna River chum salmon stocks. These data and analyses may be compared with information available in the literature.Two literature sources were located summarizing chum salmon spawning data which could be used to evaluate the suitability criteria developed in this study.These include the literature survey by Hale (1981)and the Terror Lake environmental assessment by Wilson et al.(1981).Utilization data collected within the Susitna River drainage are similar to the ranges summarized in the literature survey by Hale.However,since the author di d not develop criteri a curves, comparisons of suitability criteria could not be made.Hale did however emphasize the importance of upwelling groundwater to chum.salmon spawning which lends credence to the binary criteria developed for upwelling in this study. 7-4-55 In the Terror Lake study,Wilson et al.(l981)developed suitability curves for chum salmon spawni ng.Although the ranges of the curves described in this study fall within the range of the Terror Lake data, differences between the two sets of criteria emphasize the importance of developing curves specific to the drainage and stock being considered. For example,the chum salmon velocity suitability curves developed for the Susitna River indicate a peak suitability in much slower waters than do the Terror Lake curves.The upper limits of the two curves,however, differed by only 0.5 ftjsec.This difference may be attributed to the fact that upwelling was not taken into account in the Terror Lake curves.The substrate suitability curves for chum salmon spawning for the two studies were similar,although the Susitna River curve had a slightly wider range than the Terror Lake curve. 4.4.2.2 Sockeye Salmon The suitabil ity criteri a developed in thi s secti on for the habitat variables depth,velocity,substrate,and upwelling represent our best estimation of the suitability for these habitat variables for sockeye salmon spawning in sloughs and side channels in the middle reach of the Susitna River which currently support spawning.The criteria are based on a limited utilization data base without correspondil1g availability data to support a preference analysis.Professional judgment based on 1i terature data and the opi ni on of project bi 01 ogi sts fami 1 i ar with middle Susitna River sockeye salmon stocks was used to modify the utilization data. Studi es whi ch presented sockeye salmon spawni ng habitat cri teri a were summarized in a literature review by the U.S.Fish and Wildlife Service (USFWS 1983).The ranges of depth,velocity,and substrate conditions observed in sloughs and side channels of the middle Susitna River were within the ranges outlined in the USFWS review.Preference or suitab"ility curves were not developed,however,making these data of minimal value for comparison. 4.4.3 Recommended Apelications and Limitations of the Suitability Crlteria The suitability criteria developed in this chapter represent the suitability of several critical habitat variables important for chum and sockeye salmon spawning (depth,velocity,substrate,and upwelling)in modelled sloughs and side channels of the middle Susitna River reach. They represent a synthesis of limited utilization and availability data using statistical analyses,literature information,and the professional opinion of project biologists famil iar with middle Susitna River chum and sockeye salmon stocks.The criteria were developed for input into the habitat simulation modelling portion of the IFIM PHABSIM models to cal cul ate composite suitabi 1ity factors to be used to project usabl e areas of spawning habitat at study sites (see Section 5.0). Application of these criteria to areas outside of hydraulic simulation modelling study sites must be determined on a case-by-case basis.For example,although it is likely that the criteria presented in this 7-4-56 ..... ~, chapter can be applied to other non-modelled slough and side channel habitats in the middle reach of the Susitna River which currently support spawning (as discussed in section 2.D),it must first be determined whether the underlying assumptions.used in the derivation of these criteria can be applied to such habitats.Prior to such uses,it is recommended that additional field data be obtained to verify the use of the criteria in such other non-modelled slough and side channel habitats.It is not,however,recommended that the criteria developed in this chapter by applied to non-modelled slough and side channel habitats whi ch do not currently support chum/sockeye salmon spawni ng or other habitat types unless it is determined that the habitat variables of depth,velocity,and substrate composti on actually 1imit the spawni ng that may occur in such habitats. 7-4-57 -- 5.0 SPAWNING HABITAT PROJECTIONS 5.1 Introduction Thi s section presents the results of the thi rd and fi na 1 step of the IFIM PHABSIM modelling system:the projection of weighted usable area (WUA),an index of spawning habitat usability.A discussion is presented of the final processes for linking the hydraulic simulation models (developed in Section 3.0)with the spawning habitat criteria (developed in Section 4.0)via a habitat simulation model (HABTAT)to project WUA of chum and sockeye salmon spawning habitat as a function of flow at the hydraulic simulation modelling study sites. 5.2 Methods 5.2.1 Analytical Approach and Methodology The final stage in calculating weighted usable area of spawning habitat using the IFIM PHABSIM modelling system involves linking the output of the hydraulic simulation models with the fish habitat criteria via the HABTAT habitat simulation computer model (Milhous et al.1981).In the initial step of this process,habitat suitability criteria index values derived from the spawning habitat suitability criteria presented in section 4.0 are assigned to each of the three habitat variable values determined for each cell within the study site for a given flow using the hydraulic simulation models presented in section 3.0. Two of the habitat variables,depth and velocity,are integral to the operation of the model.The third habitat variable can represent any other habitat variable (or combination of habitat variables)considered important for spawning that acts independent of flow;that is,the habitat variable value and the corresponding suitability criteria index value assigned to the cell must remain constant for all flows evaluated. Substrate,upwelling,and cover are the most common habitat variables used in conjunction with depth and velocity in the model.In this study,the model was run using a combined sUD'strate/upwelling criteria function to represent the third habitat variable as both these habitat variables are of importance in terms of spawning at the study sites evaluated. Depth and velocity values for each cell were provided by runs of the hydraulic simulation models presented in Section 3.0.The combined substrate/upwelling habitat variable value was assigned to each cell using a two digit code.The first digit represented the substrate classification value and the second digit indicated the presence or absence of upwelling.Each cell was assigned a second digit value of either 1 for upwelling present or 0 for upwelling absent.This upwelling classification was based on accumulated field data and observations as supplemented by interpretations of aerial photography of open winter thermal leads (see Section 4.0). After habitat suitability values were determined and assigned to the three habitat variable values for each cell,the model calculates a Joint Preference Factor (JPF)for that cell which is a function of the 7-5-1 habitat suitability values determined for that cell.In this chapter, the JPF was calculated using the standard calculation method (Bovee and Cochnauer 1977);that is,the JPF for each cell was calculated as the product of the habitat suitability values determined for each of the three habitat variables predicted to be present in that cell at an evaluated flow. Alternative methods for computing the JPF (the geometric mean and lowest limiting parameter methods)were judged inappropriate,although the use of binary criteri a for upwell i ng impl i citly acknowl edges the 1imiti ng factor concept.Output from habitat simulation model runs using alternative computational methods (Tabl~7-5-1)are on file at the ADF&G Su Hydro Office,2207 Spenard Road,Anchorage,Alaska 99503. After calculation of the JPF was completed for each cell,the HABTAT model computes a WUA of the cell.The model calculates WUA of a cell 2Y multiplying the JPF value of a cell by the area of the cell (ft) derived from the output of the hydraulic simulation model.The WUA values for all .cells are then summed by the model to obtain the total WUA for the modelling study site for the particular flow being evaluate~.The final WUA value is expressed as square feet per 1,000 feet (ft /1000 ft)of channel the model is defined as representing.The entire process is then repeated for other flows to assess the influence of flow on WUA at the study site.In this report,the WUA projections only apply to modelled areas of the study sites and have not been extrapolated to the overall study site.The applicability and limitations of such extrapolations are discussed in Sections 2.0 and 5.4.3. In this chapter,the HABTAT model was used to calculate WUA of chum and sockeye salmon spawning habitat for the four hydraulic simulation modell i ng study sites that currently support chum and sockeye salmon spawning (Sloughs BA,9,and 21,Upper Side Channel 11,and Side Channel 21)and for the two modelling sites which did not currently support spawning (Side Channel 10 and Lower Side Channel 11).Runs of the model were made for the range of flows within the recommended extrapolation range of the hydraulic simulation model (Table 7-3-14).Because spawning was not documented at the Side Channel 10 and Lower Side Channel 11 study sites,tne WUA projections for these study sites were not used as an index of usable spawning habitat at these study sites.Instead, these projections were only used for comparison with model projections at sites which currently support spawning (refer to section 5.2.2.). Output of the habitat simulation model runs were then entered into a microcomputer worksheet program so additional analyses of the data could be performed.Plots comparing WUA of spawning habitat to gross surface area as a function of site flow were constructed for each study site. Additional plots of WUA as a function of site flow using an expanded WUA scale were also constructed for each site to better depict and compare trends of WUA as a function site flow within and between study sites. The controlling discharge (i.e.,the mainstem discharge at which the site flow becomes directly controlled by mainstem discharge)was superimposed on each of these plots. 7-5-2 ~, - ~. Table 7-5-1.Runs of the habitat simulation model completed using other. computational methods. JPF Computgt~onal Method ' Standard Calculation Standard Calculation Geometric Mean Geometric Mean Lowest Limiting Factor Lowest Limiting Factor Lowest Limiting Factor Thi rd Habitat Component Evaluated Substrate Upwell ing Substrate Upwell ing Substrate Upwelling Combined Substrate/Upwelling a Output from these additional runs of the model are on file at the ADF&G Su Hydro Office,2207 Spenard Road,Anchorage,Alaska 99503. b The HABTAT model was not run using the geometric mean computational method with the combined substrate/upwelling as the third habitat variable.The model assumes three variables are being input and therefore calculates the cube root of the products of the suitability factors for each variable:-rather than correctly calculating the fourth root of the product.Accordingly,this calculation method is not appropriate in the case of a combined substrate/upwelling "third" variable component. 7-5-3 The relationships between WUA and gross surface area to mainstem discharge were also plotted for periods when the site flow was directly controlled by mainstem discharge during the months of peak spawning (August and September).Additional plots using an expanded WUA scale were constructed for each site to better depict and compare trends of WUA as a function of mainstem discharge at and between study sites.The x-coordinate values on these plots were derived using site-specific flow/mainstem discharge rating curves (Table 7-5-2). From these dat~~predictions of WUA of chum and sockeye salmon spawning habitat that corresponded·to the mean daily discharge levels observed from August 1 to September 30 (the period of peak spawning activity in these habitats)for the years 1981~1982~and 1983 were interpolated from the WUA/mainstem discharge relationship.These data were used to construct a time series plot of WUA at each of the study sites.If the mainstem discharge for a particular day exceeded the recommended extrapolation range of the hydraulic simulation model~a WUA value of 0 was entered into the time series.For days when the mainstem discharge did not control the site flow,a WUA value associated with an average base flow present during uncontrolled conditions at each site was entered into the time series (Table 7-5-3).The mainstem discharge record for the USGS Gold Creek gagi ng stati on #15292000 for the same period was superimposed on each of these plots for comparative purposes. 5.2.2 Model Validation To test the hypothesis that sites which do not currently support chum/sockeye salmon spawning should have lower WUA projections than do sites which currently support chum/sockeye salmon spawning,projections of chum and sockeye salmon spawning WUA were completed for the two study sites at which chum/sockeye salmon spawning has not been observed (Side Channels 10 and Lower 11).These projections were used for comparison with the projections of WUA of chum and sockeye salmon spawning habitat calculated for the study sites'which currently support chum/sockeye salmon spawning. To compare the relative amounts of projected upwelling area and usable spawning habitat available at each study site to the relative spawner use of each study site,the ratios of projected total upwelling area and chum and sockeye salmon spawning WUA to gross surface area at a mainstem discharge of 16,500 cfs were calculated for each study site.To determine the degree of correlation between these variables,a Spearman rank correlation coefficient was calculated for each relationship (Dixon and Massey 1969).These ratios were used as a relative indicator of the amount of upwelling area and usable spawning habitat at study sites. The ratios were calculated at a mainstem discharge of 16,500 cfs as this discharge represents the average mean monthly discharge for the months of August and September based on the historical flow record.For study sites at which the site flow was control.led by mainstem discharges exceeding 16,500 cfs~the typical base level values of ·WUA and gross surface area present during non-controlled conditions at each study site were used in the calculation (Table 7-5-3), 7-5-4 - - ,~ Table 7-5-2.Relationships of site flow to mainstem discharge used to derive plots of WUA of spawning as a function of mainstem discharge for each site when the site flow was directly controlled by mainstem discharge (Estes and Vincent-Lang 1984:Chapter 1). Study Site Site Flow/Mainstem Discharge Relationship Slough 8 Qs =10-19.2034 (Qms)4.6359 Slough 9 Qs ::::10-37.7897 (Qms)9.0556 ~Slough 21 Qs 10-48.6021 (Qms)11.3182= Side Channel 10 Qs ::::10-35.5566 (Qms)8.5446 Lower Side Channel 11 Qs =10-3.2278 (Qms)1.5460 Upper Side Channel 11 Qs ::::10-19.9340 (Qms)5.0729 "":' Side Channel 21 Qs =10-11.0238 (Qms)3.1632 Key:Qs =Site Flow Qms =Mainstem Discharge 7-5-5 Table 7-5-3.Typical base flows and associated WUA 1 s (ft2/1000 ft)for non-controlled flow conditions at study sites. ~) Study Site Site Base Flow (cfs)Chum WUA (xl000) Sockeye - Slough 8A 10 2.5 3.7 ~ Slough 9 5 2.4 5.0 Slough 21 5 5.2 6.8 m" Upper Side Channel 11 5 3.3 5.2 -Side Channel 21 25 2.3 4.5 Side Channel 10 5 0 0 ***lower Side Channel 11 *This side channel was controlled by mainstem discharge during August and September 1981,1982,and 1983. - - ..." 7-5-6 5.3 Results 5.3.1 Weighted Usable Area Projections 5.3.1.1 Chum Salmon Projections of gross surface area and WUA of chum salmon spawning habitat as a function of site flow for the modelling study sites at which chum/sockeye salmon spawning has been documented (Sloughs 8A,9, and 21,Upper Side Channel 11,and Side Channel 21)are presented in Figures 7-5-1 through 7-5-5.For the range of flows at each study site that are directly controlled by mainstem discharge,the gross surface area and WUA projections as a function of mainstem discharge are also presented.Data used to develop these plots are presented in Appendix Table 7-D-1 through 7-D-5. Typically,projections of gross surface area at each of the study sites increase with increasing site flow and mainstem discharge.The most rapid increases in surface area generally occurs at the lower site flows prior to the site flow becoming .controlled by the mainstem.Subsequent to the flows at the study sites becoming controlled by mainstem discharge,the increase in gross surface area begins to level off. Projections of WUA of chum salmon spawning habitat at each study site generally follow similar trends as the projections of gross surface area,with the exception that projections of WUA peak or level off at some site flow/mainstem discharge.Overall,the projections of WUA are less than 20%of the projected gross surface area at a given study site. Typically,the peaks in WUA of spawning habitat occur when the site flow is directly controlled by mainstem discharge,usually in the range of mainstem discharges from 20,000 to 35,000 cfs.An exception to this trend is Side Channel 21 where two peaks in WUA of spawning habitat occur (Figure 7-5-5).The first peak coincides with overtopping by the mainstem and the second at a mainstem discharge greater than 30,000 cfs. The bimodal shape of the WUA curve for this site is likely linked to the specific channel geometry and hydraulic characteristics of this side channel. Although peaks in chum salmon spawning WUA typically occur when the site flow is directly controlled by mainstem discharge,these conditions generally prevail less than 40%of the time in August and September for slough study sites and 75%of the time for side channel study sites (Table 7-5-4).This indicates that whereas high values for WUA may be projected for a particular study site,these projected values occur only infrequently under the existing mainstem discharge 2regime.For example,comparatively high WUA values exceeding 7,800 ft /1000 ft are possible for Slough 8A at mainstem discharges exceeding 33,000 cfs; however,based on the historical 30 year discharge record,these discharges occur only 4%of the time during the period of peak spawning (August through September). Time series plots of chum salman spawning WUA projections as a function of mainstem discharge (for the period August through September during 7-5-7 SLOUGH 8A CHUM SALMON SPAWNING ~J .~ ---SITE FLOW AT I 80 CONTROLLING DISCHARGE •~80 ---g~~~~~~~NG MAIN STEM r 1 70~I 70 1~I ~I t 60 .::1 t 60 iiilil~';:1 O~0 1 ~R "'I ~R 01 i!i ~50 I i!i ~50 ~1 ~~I ~~"'I wl!40 1 wl!40 1 ~t:.1 ~t:.I 0:30 I 0:30iilI::J Im1 20 I 20 I I I 10 -I I 10 I ..a B B ..I..B ~~B 1 I o 0 o 20 40 60 80 0 10 20 30 40 SITE FLOW (CFS)MAINSTEU" h 81'§'C'l.;',&6E (CFS) .......26 26 I I IU124---SITE FLOW AT 24 ---CONTROLLING MAINSTEM I I 22 CONTROLLING DISCHARGE I 22 DISCHARGE ..I CO .:1 ~ 20 ul 20 I~:l 81 t 18 £18 ~I g~16 o~16 "'I~~I~~14 i!i~14 I «~12 ~!!l 12·1~~Ii1:~10 i1:~10 I ~B V ~B l-.a_---"_--e---....,,'!m r 6 6 I 4 4 I "I 2 "2 I o 4 G3 0o20406080 0 10 20 30 40 SITE FLOW (CFS)MAINSTEU"h81'§'CD~t':6E(CFS) Q GROSS SURFACE AREA 0 WUA :CALIBRATION FLOWS (MIN.a MAX.) Figure 7-5-1.Projections of gross surface area and WUA of chum salmon spawning habitat as a function of site flow and mainstem discharge for the Slough 8A modelling site. iJ J I 0'J J I !)I J I })J J 5 I ) ~-J } SLOUGH 9 CHUM SALMON SPAWNING 1.J,c:8 8 8 B --e----e-------e-----...-e-----.--a--------a---------s---_fJ 40 1 I I I I, I I ·1 ':;1 81~I -L.".....~ I .1 ':;1 8V\' !!!I 1 . 1 I 10 20 30 MAINSTEU1jl~~~A~aE(eFS) ~I"i I I I 10 20 30 40 MAINSTEUh81~~~~RaE (eFS) :CALIBRATION FLOWS (MIN.8 MAX.) ---CONTROLLING MAINSTEM DISCHARGE - - -CONTROLLING MAINSTEM DISCHARGE '50 '40 130 '20 110 f 100a 90Ul~ ~~ L5g aD "'~70«'0 "Lc 60~b '"50::J Ul 40 30 20 10 0 0 26 24 22 20 f 'a a '6Ul-~. L5g 14"'.«'120 1.LI..t:Ul-10«~ '"'"a::J Ul 6 4 2 0 0 600 -----., o WUA 600 ---SITE FLOW AT CONTROLLING DISCHARGE 400 SITe FLOW reFS) '"" 200 ~_..--.--....-+------'€> -~--.....---....-.,.-------SITE FLOW AT CONTROLLING DISCHARGE o GROSS SURFACE AREA Figure 7-5-2.Projections of gross surface area and WUA of chum salmon spawning habitat as a function of site flow and mainstem discharge for the Slough 9 modelling site. SLOUGH 21 CHUM SALMON SPAWNING 40 40 y 1 .,I-:;1 0 181.;~ 10 20 30 (ThoU15Qnds) MAINSTEM DISCHARCE (CFS) ---CONTROLLING MAINSTEM OISCHARGE ---CONTROLLING MAINSTEM DISCHARGE --+-------r-I I I I I I I 10 20 30 (Thousands) MAINSTEM DISCHARCE (CFS) 100 :CALIBRATION FLOWS (MIN.a MAX.) Figure 7-5-3.Projections of gross surface area and WUA of chum salmon spawning habitat as a function of site flow and mainstem discharge for the Slough 21 modelling site. 100 ~-- 90 -j I -----&-----90 80 I!!80v~~---SITE FLOW AT CONTROLLING DISCHARGE ;=-70 E 70 L a 0 ~~60 1Il~60~~ u u ~§50 ;:;'i6 50rr."'~-1 ,«3 0 I a l..d .c:W-c Uf-40 Of-40«-I «~ I,L. '"I '"::J 30 :::J 30IIII1Il 20 I 20 10 -Ir-e-s-------------s-------------<l-----10 -----£] o I I I ---,--I 0 0 100 200 300 400 0 SITE FLOW (CFS) 26 ---------------.__..-26 .......24 ---SITE FLOW AT 24 I CONTROLLING OISCHARGE 01 22 22 I 20~,20 0 E E 1818 0 16 0 161Il~1Il~ ~~~~ <5 11 14 ~";:;'i~14",g ~"'~..,12 «'12wl!aW-c Uf-------~--~-~Uf-10«~10 «~ L.L. '"'"::J B :::J 8 1Il ~---------I:J 1Il 6 6 4 2 2 0 II!?I I·--·--~------r-I I 0 0 100 200 300 400 0 SITE FLOW ICFS) o GROSS SURFACE AREA o WUA J J t I I J J I 1 1 1 1 J J I J J } -=--1 =~~l --~1 J 1 -----------~--1 140 40 40 :!I~I &1'91 ~a..., v ---CONTROLLING MAIN STEM DISCHARGE 10 70 90 40 100 110 130 120 20 0 0 10 20 30 26 - MAIN5TFUh&~}~"ttAF (CFS) 24 ---CONTROLLING MAINSTEM DISCHARGE 22 20 E 1 18 I 0 16 1U1~~..-0 or.1i<14o:~til.., 0 12 °1W.c UI-&1,,~10..ll!0: :::>8U1 6 I 4 1 2 1 1 0 0 10 20 30 MA'NSTE\JhD"§C"..;'A~2:E (eFS) :CALIBRATION fLOWS (MIN.a MAX.) 30 oU1~ .......r1 810.1i~o:~",I.JJ~sa~G 50 0::::> U1 E 240 240 200 a WUA ~ 160 ---SITE FLOW AT CONTROLLING DISCHARGE 120 '> '" SITF FlOW (CF5) ao40 o GROSS SURFACE AREA 1 I I ..I til lGl I 1 I I '>'1 "11 1 12 I l---------r--,.--r 110 I I I ----.-I I I I o 40 80 120 160 200 51Tt FLOW reFS) 120 110 100 90 E 80 0 U1~ 70;1 600:. ·00 W.c •50m- ,,~ I.: 400: :J U1 30 20 10 0 0 -.....J 26 I 01 24 f-'22 f-' 20 E 18 0 16U1~~. .1i]14 0:.",12W~ UI-10,,~.. 0: :J 8 U1 6 4 2 0 Figure 7-5-4.Projections of gross surface area and WUA of chum salmon spawning habitat as a function of site flow and mainstem discharge for the Upper Side Channel 11 modelling site. 40 40 ---CONTROLLING MAINSTEM DISCHARGE 10 ---CONTROLLING MAINSTEM DISCHARGE I I I Inl 0 1~I~I I I I ~~~~----r---~J-----r----·-··--,L __."..r--·'·~---2TO ,30 10 (Thousands6E (CFS) MAINS rEM DISCHAR 240 260 220 200 f lBO a 160VI-~-1l ~g 140 a:_ "-'1200liLc UI-100.,-- L-a: :J BOVI 60 40 20 0 0 26 24 22 20 f lB a 16VI~--U~c 14cd.,-,120 I"LUI-10.,-~ L- et: :J BVI 6 4 2 0 1.6 01.4 ---SITE fLOW AT CONTROLLING DISCHARGE ---SITE fLOW AT CONTROLLING DISCHARGE SIDE CHANNEL 21 CHUM SALMON SPAWNING ~_4--'"I ----&-----y-,,--......r---.----....-----~ B o -fE.I Y.,....,.,TJ3djl.a,-.."'!'·"'"1jI 1jI 'i'r----1'T JF-'-4l- o 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 sl~lh~~~~np~~S) 14 16 12 10 24 26 r I 22 j .=1 20 ~I 1B 1-1 I I 1 I 1 I ~ I ..g__-g__'6kt _Et---•..--'..a--I4·~"a----G----,-r':-"'Sss'5-e-s-.B-B----B-'"-,----.----T 2 .'"I _--'--""'--",716';1 1.2 ----y---~6 O.ds o 023 -0.4 O.(rhOU6~"(cfs)ci 0.2 SI((FL f a ~n ~-~ a:_.,-, .,2 Uf- .,-~ L-a: :J VI 260· 240 220 200 ;::- L-lBO a VI~160 ~~140 et:".,-~ w O u;O.,-- U. et: .CJ VI 60 40 20 '-J I Ul I I-' N o GROSS SURFACE AREA a WUA ~CALIBRATION FLOWS (MIN.a MAX.) Figure 7-5-5.Projections of gross surface area and WUA of chum salmon spawning habitat as a function of site flow and mainstem discharge for the Side Channel 21 modelling site. J J }I J J J J ]t .1 J J I i I J 1 ,) Table 7-5-4.Range of WUA (ft 2/1000 ft)of chum salmon spawning habitat during non-controlling and controlling mainstem discharges and the percent of time the sites are not controlled and controlled by mainstem discharge during August and September. NOT CONTROLLED BY MAINSTEM Q CONTROLLED BY MAINSTEM Q Study Site Controlling Discharge (cfs) %of Days in August & September a Range of WUA (xl000) %of Days Range in August &of WUA September a (xl000) Slough 8A 33,000 96 2.4-7.8 4 7.8-8.3 Slough 9 19,000 60 2.4-4.3 40 4.3-9.1 Slough 21 24,000 84 5.2-8.5 16 6.6-16.4 Upper Side Channel 11 16,000 47 3.3-8.2 53 8.2-14.4 Side Channel 21 12,000 27 2.1-3.9 73 1.2-3.8 a Based on 30 year historical record. 7-5-13 the years 1981,1982,and 1983)are presented in Figures 7-5-6 through 7-5-10.These plots depict the temporal variability of chum salmon spawning WUA at each study site during the months of peak spawning activity.In general,sites which have lower controlling discharges provide more WUA for chum salmon spawning over time (e.g.,Slough 9 and 21)than do sites which have higher controlling discharges (e.g.,Slough 8A).The exception to this trend is Side Channel 21,which has a low controlling discharge and low projections of WUA of chum salmon spawning habitat.Additionally,sites which have lower controlling discharges such as Slough 21 and Upper Side Channel 11 exhibit larger variations in chum salmon spawning WUA over time than do sites which have higher controlling discharges as does Slough 8A. The projections of available chum spawning WUA were generally greater in 1983 than in 1982.The reason for this is likely linked to mainstem discharge levels.Mainstem discharges during the months of August and September were higher in 1983 than in the previous year (Figure 7-5-11). Insufficient data are available for the 1981 time series plots,due to the occurrence of hi gh f1 ows above the upper extra po 1ati on*range,to compare the 1981 WUA projections to 1982 or 1983 projections.However, based on the historical discharge record (Figure 7-5-11),it appears that usable habitat in the relatively high flow year of 1981 would have exceeded that available in either 1982 or 1983.Information presented in Figures 7-5-11 and 7-2-2 indicates that the 1983 period of measurement most closely approximates the historical 30 year period of measurement. 5.3.1.2 Sockeye Salmon Projections of gross surface area and WUA of sockeye salmon spawning habitat as a function of site flow for the modelling study sites at which spawning has been documented (Sloughs 8A,9,and 21,Upper Side Channel 11,and Side Channel 21)are presented in Figures 7-5-12 through 7-5-16.The gross surface area and WUA projections as a function of mainstem discharge are also presented for the range of flows at each study site that are directly controlled by mainstem discharge.Data used to develop these plots are presented in AppendiX Tables 7-0-1 through 7-0-5. *Models were calibrated to assess changes in WUA at naturally occurring discharges within the range of discharges expected to resu It from development of the proposed hydroe 1ectri c facil ity. Consequently,upper extrapolation ranges are often lower than naturally occurring discharges.Therefore,projections of WUA could not be made for high discharge events. 7-5-14 - - - SLOUGH 8A CHUM 26 60 24 1981 .. 22 -u 20 0 0 5?18 40 .. 16 III~.."D""c 14 II::::l~C[ ::I:;I:~12 t)0.<:..t:.10 C 20 :28III I- 6 .. Z 4 Ci ;( 2 0 0 AUG-01 AUG-16 AUG-.31 SEP-15 SEP-.30 ---------------------- ...-----------------------r'60 1982 III.. II: C[ :l: t).. C 20 :E III...... Z Ci ;( o SEF'-.30SEP-15 g 5? 40 .. ..u AUG-.31AUG-16 2 o AUG-01 26 24 22 20 18 -;;-16 "D""C 14:::l~ ;I:~120.<:t:.10 8 6 4 --------------------~- .,....-----------------------,-6026 24 22 20 18 -;;-16 """C 14 :::l:l-;I:~12 " I 0.<: , !t:.10 !I 8 6 4 2 III.. II: C[ ::I: t).. C 20 ;( III I-.. Z Ci ;( o SEP-.30 UPPER MODEl.EXTRAPOI.ATION I.IMIT CONTROI.I.ING BREACHING DISCHARGE SEP-15 1983 ..-u o ~40 .. AUG-.31AUG-16 o AUG-01,"'"i Figure 7-5-6.Time series plots of chum salmon spawning WUA as a function of mainstem discharge for the months of August through September,1981,1982,and 1983 for the Slough 8A modell ing site. 7-5-15 SLOUGH 9 CHUM o SEP-30 1981 SEP-1S 4 2 0..J,-.~,.J,lI,l~~~,...........~""",,,,, AUC-01 AUC-16 AUC-31 26...-------------------------,-60 24 ·n g 20 g 9 18 40 ~ 16 ~ ~ 14 ~ :t:12 0 III 10 Q 8 J--....g.-------tll;.",...~~--------____f"20 ~ I- 6 ~ ~:a ""'" - ·-g oo 2 40 o SEP-30 1982 SEP-1SAUC-3'AUC-,S 6 4 ~ ~ ~ <I :t:o III Q 8 ..R-~---------__:----_t11:rft;;;;;_\_-..,-20 ~ I- III Z ~:a 2 o AUG-01 26..,.....----------------------,-'60 24 :2.0 18 16 14 12 10 :2.2 - 8 9 ·!i 1983 18 22 20 26..,.....----------------------,-110 :2.4 40 UPPER MODEL EXTRAPOLATION LIMIT CONTROLLING BREACHING DISCHARGE - o SEP-30SEP-1S .......---------..,-20 AUG-31AUC-'6 4 6 :2. a AUG-a' 16 14 12 '0 8J----l:IIt-fi;;tIl:lf:l1.....d'-otri:t--c Figure 7-5-7.Time series plots of chum salmon spawning WUA as a function of mainstem discharge for the months of August through September.1981,1982,and 1983 for the Slough 9 modelling site. 7-5-16 SLOUGH 21 CHUM 26 60 24 1981 22 .. <> 20 0 0 111 52 40 .. 16 -~·... ."~<"14 a::>~..;I:~12 :l:a r.>-'=rnt;.10 i5 II 20 2... ~ 6 rnz 4 .. :::E 2 0 0 AUG-OT AUG-16 AUG-31 SEP-15 SEP-30 ... ~a:.. :l:r.>.. 5 20 :::E... ~rnz <i :::E ... ~a:.. :l:r.>rn 5 20 :::E... ~.. Z ;( :::E .. <> oo 52 40 .. .. <> oo 5240JC o SEP-30 o SEP-30 1983 1982 SEP-15 SEP-15AUG-31 AUG-31AUG-T6 AUG-Til ..,.------------------------.-60 ..,.------------------------.-60 2 0 AUG-Ol 26 24 22 20 III ~T6·." <"14:>ll ;I:~12•E 10 II 6 4 2 0 AUG-Ol 211 24 22 20 111 ....16 ." <"14:>ll ;I:~12a-'=t;.10 II 6 4 'i I I "T I UPPER MODEL EXTRAPOLATION LIMIT CONTROLLING BREACHING DISCHARGE Figure 7-5-8.Time series plots of chum salmon spawning WUA as a function of mainstem discharge for the months of August through September.1981.1982.and 1983 for the Slough 21 "modelling site. 7-5-17 UPPER SIDE CHANNEL 1 1 CHUM ..,...------------------------r60 - - .... ., u oo 40 ~ o SEP-30 1981 SEP-'5 ..., '"It:... :I: ---------~~~~---------~~ is 20 ::E I=-..,.......-----~~ '"Z;;: ::E 2 o-',....~~~~......,,............~~~ AUG-a'AUG-,6 AUG-3' 26 24 22 20 'B '6~ ."<c 14:::l~ ;t~'2Q.ct-'a B 6 4 ,"" - -. - :... oo S! 40 .. ..., '"a:... :I:o <II is 20 ::E..., :- '"z <i ::E :.u oo S! 40 .. o SEP-30 198~ 1982 SEP-,5AUG-3'AUG-16 2 a AUG-O' B 4 6 26..,-------------------------,60 24 22 20 'B '2 '0 26 ~ 24 22 j20 'B '6 '4 '6 4 2 o AUG-O'AUG-,6 AUG-3,SEP-'5 ..., '"a:... :I:o <II is 20 ::E..., :- '"z <i::E o SEP-30 - UPPER MODEL EXTRAPOLATION L.IMIT CONTROL.L.ING BREACHING DISCHARGE Figure 7-5-9.Time series plots of chum salmon spawning WUA as a function of mainstem discharge for the months of August through September.1981, 1982,and 1983 for the Upper Side Channel 11 modelling site. 7-5-18:,~ SIDE CHANNEL 21 CHUM 26 ...,....------------------------,-60 .. ~., oo 2 40 .=. '... "a: c[ :J: <.l til Q 20 ::E...... til Z C( ::E o SEP-30 1981 SEP-1SAUG-31AUG-16 :-l.JlL~...,....-...JJ6wwmlll AUG-01 61------------------"'''''-''''''_.......;;:---1 4 B 10 14 12 22 20 lB 16 24 ,Ff' I I I .... I i 26...,....------------------------,-60 24 1982 22 20 lB 16 14 12 10 B 6 4 2 o AUG-C'AUG-'6 AUG-!1 SEP-1S oo 2 40 .=.... "a: c[ :J: <.l til is 20 ::E...... til Z C( ::E o SEP-30 26 -,-------------------------,-60 24 1983 22 .:.. oo 240.. ... "a: c[ :J: <.l tilo 20 ::E...... til Z C( ::E o SEP-!O UPPER MODEL EXTRAPOLATION LIMIT CONTROLLING BREACHING DISCHARGE SEP-1SAUG-31AUG-16 4 6l----------------"'''''-=---r-..----i :-aat[illijmflOOf~Wi!8WU~~WiW AUG-01 10 B 14 '2 'i' I I T I Figure 7-5-10.Time series plots of chum salmon spawning WUA as a function of mainstem discharge for the months of August through September,1981,1982,and 1983 for tne Side Channel 21 modelling site. 7-5-19 e 6 - 4.. ~o 3- 6 AUGUST Mean Monthly Discharge (USGS Gaoino Station 15292000) •=1981 A =1982 •=1983" .., 4 o 10 20 30 40 50 60 70 80 90 100 - %OF TIM E DISCHARGE EQUALLED OR EXCEEDED SEPTEMBER Mean 'Monthly Discharge (USGS Gat;ling Stat ion 15292000) •=1981 •=1982 •=1983'" 6 4-..~3 o- 6 4 o 10 30 40 50 60 70 80 90 100 -. - %OF TIME DISCHARGE EQUALLED OR EXCEEDED ·Prov is ional Data Figure 7-5-11.Flow duration curves and mean monthly discharges for August and September based on the 30 year record of Susitna River discharge at Gold Creek.Sources: time duration curves -Bredthauer and Drage (1982); mean monthly discharges -USGS (1982),Lamke et al. (1983),and USGS (provisional data). 7-5-20 I 1 -1 ~~---1 _--,::.1 SLOUGH SA SOCKEYE SALMON SPAWN ING::r-----~~90 -___-..0-_--_._- ---CONTROLLING MAINSTEM P___....--.__~_.-(0 Bo DISCHARGE~----_.-I 70 ~.I 70 I f 60 ---SITE FLOW AT ..I f BO I a CONTROLLING DISCHARGE ';;1 a ~IU1~U1~ ~"~"glu50:Ill i1j-g 50i1ig",g ~I"'"I«'«, 0 40 W~40 "'IW.e IUt-Uf-"'-«~ 1...I IL '"3D '"3D :J I :J 1VIU1 20 I 20 I I 110.-j 10 I'-"a---0 B B I B 0 []--__-e-------e---a--B B 0 0 0 20 40 60 Be 0 10 20 30 40 -...,J Uhousondsd: I SITE FLOW rCFS)MAINSTE OISCRAR E rCFS) <r'26 ---------_._--------------26 N 24 ---SITE FLOW AT I 24 ---CONTROLLING MAINSTEM Pol CONTROLLING DISCHARGE DISCHARGE 22 I 22, J5120120 f .1 f 01 lB lB §Ia16 ':;1 aU1~:Ill (II~16 "'I~"~"i1j~14 I i1ig 14 1",g "'"1«'12 I «'12w~W~w-10 1 Ut-I«~«-10ILIL '""~-e-----<J '"Ira:J B :J BU1.~I (II 166~_-.r I I4V'a--'--I 4 IA 2 I 2 I 0 I 0 ,I 4 -.-,I ----,-----,53 ,,,-.--"--~I 0 20 40 60 BO 0 10 20 30 40 UhOLJsandS6~ITF FI OW rCFS)MAINSTE OISCHAR E rCFS) o GROSS SURFACE AREA o WUA :CALIBRATION FLOWS (MIN.a MAX.) Fig~re 7-5-12.Projections of gross surface area and WUA of sockeye salmon spawning habitat as a function of site flow and mainstem discharge for the Slough SA modelling site. SLOUGH 9 SOCKEYE SALMON SPAWNING ,50 •.•_•.___•0.'_'__,___".150 140 l 140 '3D --------<>130 ~---CO~TROl-L1~G MAI~STEM DISCHARGE 120 -.-----'20--110 ---SITE Fl-OW AT '10 f 100 CO~TROl-L1~G DISCHARGE f 'DO a a ~~90 U1~90~{l ~'.!80 ~~80 "'~"'.<0 70 <t'70 ",J!c"'I ~t:.60 Uf-60<t~ "-"- '"50 '"50 ::J OJ U1 40 U1 40 30 30 20 20 10 ':L r----l=--T~~e---a """""EJ 0 I 0 200 400 600 0 '0 20 30 40 SITE FLOW (eFS)MAIN~TEUh~I~~~.s:AE (CFS) 26 ---_._.__._-------26 "'"-.l 24 I -'--SITE fl-OW AT 24 1 - - -CONTROl-UNG MAI~STEM I I CONTROl-U~G DISCHARGE DISCHARGE 01 22 22 I IiiN20 20 N f I'"f18 '8 a 16 I a '6!!!,n-I ~n ~§14 L:i§14 I"'.I "'.<t'12 <t,'2 ill",J!I ",j! ~c.10 Uf- '0 01<t~ "-I "-81'"'"::J 8 ::J 8 <Ii U1 Q U1 -1'6 "6 4 ~~4 2 O~---,232 --------r -----T-------------,-----·f I 0 0 200 400 600 0 10 20 30 40 SITE FLOW (eFS)MA'NSTEUhD/~~H:R6E (CFS) o GROSS SURFACE AREA o WUA ~CALIBRATION FLOWS (MIN.a MAX.) Figure 7-5-13.Projections of gross surface area and WUA of sockeye salmon spawning habitat as a function of site flow and mainstem discharge for the Slough 9 modelling site. J J 1 1 I I ~I )I ,I J I J ~I 1 ~ j --~-=---l ---~.~ SLOUGH 21 SOCKEYE SALMON SPAWNING 40 1 I ..I'tl 81 ~~:tl~ 20 30 (Thou9Qnd!ll )MAINSTE~DISCHAR{;E rCfS) 10 I \J ---",---__",,---'1",-----,,--------,- 10 20 30 40 MAINsTEUhD,~cHt~6E (CfS) ---CONTROLLING MAINSTEM DISCHARGE ---CONTROLLING MAINSTEM DISCHARGE 90 BO E 70 a Ul-60~"";,;,;c"'~50.., 0W.c~t.40 "-'":J 30Ul 20 10 0 0 26 24 22 20 E 18 a 16Ul~~""14iliij "'"<f'12wi! Ot-10<f~ "-'":J 8Ul 6 4 2 0 0 400 400 --<> 100 200 300 SITE fLOW (CfS) 100 II ~~-..---...----y _-------SITE FLOW AT=CONTROLLING OISCHARGEIU IQ I . I I I I I 1~--~--B --£ 1 I I I I I I .-. o o o r----o-------,-------~____..sT I I I ~i I o 100 200 300 • SITE fLOW rCfS) 1B 16 ------------'-1 ---SiTE FLOWNAGT DISCHARGE- -CONTROLLI 26 •1 I I 1=I~I- I 14 rl , 12 1 .v ':I •"'~"'~""""--'--"<fl6"I 4 1 I 2 I 20 22 24 100 90 BO E 70 a ~:;-60 ";,;,;c,d 50.., 0W.c ~C 40 lL '":J 30Ul 20 10 E aUl~~"";';';5 ~~ wi! Uf--..~ lL '":J Ul -.....J 1 (.J"] I N W o GROSS SURFACE AREA o WUA :CALIBRATION FLOW~(MIN.flMAX.) Figure 7-5-14.Projections of gross surface area and WUA of sockeye salmon spawning habitat as a function of site flow and mainstem discharge for the Slough 21 modelling site. 403020 MAINSTEUh81't;~aH~~6E (CFS) --------.-._----- V I til 81 ~I-, I r-~ -~----,------~<-'-----.-----.-- 10 ---CONTROLLING MAINSTEM DISCHARGE ---CONTROLLING MAINSTEM DISCHARGE o o 10 - 22 20 - 26 40 24 50 3D 20 130 '4(1 240 -&----E- ..-- 200 -- UPPER SIDE CHANNEL II SOCKEYE SALMON SPAWNING " 120 110 f 'DO a 90 U1~-~80i'fj~a:III 70"',~&60"'-I>- 0: ::J UI 160 ---SITE FLOW AT CONTROLLING DISCHARGE 120 SITE FLOW (eFS) 80 --T 40 I I Itil ..----~-...-<>-...---- tr ",IO/y'-----SITE FLOW ATCONTROLLING OISCHARGE I I I I I I I I ......!aaaBa-a-e-tr'I a-e--B-<>--a a 8 B a -,-----r---_r--u .. 24 20 22 120 110 100 - 90 f 80a U1~ ;~70 n:~60.., ",2 50 -Uf-..-LLn:40::J UI 3D 20 10 0 0 26""'-l I ()1 I N.po f a U1~~"lJ i'fj'n:~.., w~UI-..~ LLn: ::J UI 18 16 4 2 o 40 240 SITE:rLOw (eFS) f 18 I a I U1~16 I-"i'fj1!14 (\"'~..'12",2 Uf-10..-LL '"::J 8 -::1III 6 "I 4 81 !il 2 I 0 .~----,---,,-1 0 10 20 30 MAINSTElih~I~'b~~~6E (eFS) ~o o GROSS SURFACE AREA a WUA :CALIBRATION FLOWS (MIN.a MAX.) Figure 7-5-15.Projections of gross surface area and WUA of sockeye salmon spawning habitat as a function of site flow and mainstem discharge for the Upper Side Channel 11 modelling site. I J J 1 ,I J )J I !)J J :1 I j J ] I SIDE CHANNE L 21 SOCKEYE SALMON SPAWNING 240 1~_1Y/~-~-~--~240 I ..--220 I/J ...-$--__.---~~-220 200 01 .----SITE FLOW AT 200 f '80 y-"""""",.""~,,f 180 a 160 -0 160tIl-~:-;--~u uLlJ~140 LlJ~140 "'""'~,.",120 <i,120w~w~Uf-100 Uf-<i-<i~100l>-I I>-'"'":J 80 I :J 80tiltil 60 I 60 40 I 40 20 I 20 0 o£F-ff11iil I li!I'iJ fjI IjI ---4'T \1 'r T=='t=4'0 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 0SI,'~h?~8wnr~fS) 26 -------~--_._------'-.--_._"---26-....,J II24 ---SITE FLOW AT 24 U1 I CONTROLLING DISCHARGEI22 22 N I U1 20 1'i1 20 f 18 lei f 18 a 16 I 0 16~W1 ~n~~14 I ~~14 "'~I "'~<i'12 <i'120Iwi!w.J: Uf-Uf-<i'-10 I <i~10I>-4-lI:'":J 8 I :J 8tiltil 6 "I 6 4 ~~~-8 4 2 2 0 I ~.", 0.023 ~r·-I--l ·----,-----ry76T---------r-~~-T~~ 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 0SI1(~hF~~~n?~fS) o GROSS SURFACE AREA o WUA ~CALIBRATION FLOWS (MIN.a MAX.) 40 40 I I .:!I~I &1 ~I I I 10 20 30 MA,NSTEUhD,~~cHnAdR6E (CFS) I I I 1 i ,el ~I 81 ~I I ~ ·-T---·------1~1--.._______._I --r--~........,-----I I 10 20 30 (ThoU50nQs) MAINSTEM DISCHARGE (CFS) ---CONTROLLING MAINSTEM DISCHARGE ---CONTROLLING MAIN STEM DISCHARGE 260260~- Figure 7-5-16.Projections of gross surface area and WUA of sockeye salmon spawning habitat as a function of site flow and mainstem discharge for the Side Channel 21 modelling site. Projections of gross surface area and WUA for sockeye salmon spawning at study sites follow trends similar to the WUA projections for chum salmon spawning,with the exception that projections of sockeye salmon spawning WUA are generally higher than are the projections of chum salmon spawning WUA during site flows which are not controlled by mainstem discharge.For example,the WUA of s~ckeye salmon spawning habitat at Slough 9 ranges from 5,000 to 6,100 ft /1000 ft for site flows which are not controlled by mainstem discharge as compared to WUA of chum ~almon spawning habitat at this site which ranges from 2,400 to 4,300 ft /1000 ft under similar non-controlled site flow conditions.In comparison, projections of WUA of sockeye salmon spawning habitat for site flows which are directly controlled by mainstem discharge are generally lower, and occur at lower flows or discharges,than do the projections of WUA of chum salmon spawnin~habitat at the same site.For example,a peak WUA value of 16,400 ft /1000 ft occurs for chum salmon spawning habitat at Slough 21 at a mainsiem discharge of 28,700 cfs as compared to a peak WUA value of 13,700 ft /1000 ft for sockeye salmon spawning habitat at this slough at a mainstem discharge of 27,200 cfs.Such differences may partially be linked to the difference in velocity suitability criteria for these two species (see Section 4.0). As with the chum salmon WUA projections,peaks in WUA of sockeye salmon spawning habitat occur when the site flow is directly controlled by mainstem discharge.As previously noted,however,these discharge conditions generally occur less than 40%of the time in August and September for slough study sites and 75%of the time for side channel study sites (Table 7-5-5). Time series plots of WUA of sockeye salmon spawning habitat as a function of mainstem discharge for the period of peak spawning activity (August through September)during the years 1981,1982,and 1983 (Figures 7-5-17 through 7-5-21)also follow trends similar to the time series plots for WUA of chum salmon spawning habitat.However,WUA of sockeye salmon spawni ng habitat occurs during non-controll i ng rna i nstem discharges and less during controlling mainstem discharges than for chum salmon spawning WUA a given study site. 5.3.2 Model Validation To test the hypothesis that sites which do not currently support chum and sockeye salmon spawning should have low WUA projections as compared to sites which support chum and sockeye salmon spawning, projections of gross surface area and WUA for chum and sockeye salmon spawning as a function of site flow were made for the study sites at which spawning has not been documented (Side Channel 10 and Lower Side Channel 11)(Figures 7-5-22 through 7-5-25).The gross surface area and WUA projections as a function of mainstem discharge are also presented for the range of site flows at each of these study sites that are· directly controlled by mainstem discharge.Data used to develop these plots are presented in Appendix Table 7-0-6 and 7-0-7 .. 7-5-26 - ~I .... '~ - ,.... i I I f"'I' i I I 1 Table 7-5-5.Ranges of WUA (ft2/lOOO ft)of sockeye salmon spawning habitat during non-controlling and controlling mainstem discharges and the percent of time the sites are not controlled and controlled by mainstem discharge during August and September. Study Site Controlling Discharge (cfs) NOT CONTROLLED BY MAINSTEM Q %of Days Range in August &of WUA September 1 (xl000) CONTROLLED BY MAINSTEM Q %of Days Range in August &of WUA September 1 (xl00G) TI 1 Slough 8A 33,000 96 3.7-8.3 4 8.3-8.4 Slough 9 19,000 60 5.0-6.1 40 6.1-7.0 Slough 21 24,000 84 6.8-9.2 16 3.5-13.7 Upper Side Channel 11 16,000 47 5.2-11.3 53 11.3-14.4 Side Channel 21 12,000 27 4.0-4.8 73 0.7-4.0 1 Based on 30 year historical record. 7-5-27 SLOUGH 8A SOCKEYE 26 60 24 1981 22 .:.. 20 0 0 18 !2 40 • "ii'16 1&1.""..:C '4 lZ::I~c(~~12 X0U.<:.,C.10 Q 20 8 2 1&1 I-6 ., z 4 ;« 2 2 0 0 AUG-O'AUG-16 AUG-3,SEP-15 SEP-30 ~! ...,----------------------.....,...6026 24- 22 20 18 "ii'16 ." ..:5 14- ::In ~~120 t-10 8 6 4 2 1982 =.. oo!2 40 • ---------------------- o SEP-30 ""'" - ..,-------------------~--__._60 ---------------------- 26 24 22 20 18 7 16 ."..:C 14::I~~~120 .<: C.10 l!l 6 4 2 o AUG-01 AUG-16 AUG-31 SEP-'5 1983 .:.. oo !2 40 • 1&1 "a:: c( ::l: U., Q 20 2 1&1 I- l/I Z Ci" ::Ii o SEP-30 UPPER MODEL EXTRAPOLATION LIMIT CONTROLLING BREACHING DISCHARGE Figure 7-5-17.Time series plots of sockeye salmon spawning WUA as a function of mainstem discharge for the months of August through September,1981 1982,and 1983 for the Slough 8A il10de 11 i ng site. 7-5-28 SLOUGH 9 SOCKEYE ~.. o ~ "10 .. o SEP-30 1981 SEP-1SAUG-31AUG-16 l&l.., a: -------------c:z: <J., aJ--"'..--20 :II '"~., Z C :II ..,------------------------r6026 24 22 20 18 ~16 ~ "D:§~14 1 ~::J 120.r: C-10 I B 6 4 2 0 AUG-01 ..,.-------------------------,-60 1982 o SEP-30 o SEP-30 1983 SEP-1S SEP-1S AUG-31 AUG-31 AUG-16 AUG-16 ---------------------,60 ~.. oo 52 40 .: '"'"a:c:z:o., C ~--'--------..:'=''------~-------:--....,20 ~ ~., Z C :Ii ~.. o ~ 40 .: '"'"a:c:z: <J., isj-...l>o::---------------+----r--r20 :II '"~., Z C :Ii 2 0 AUG-01 26 24 22 20 18 ~16 ~ "D:§~14 ~::J 120 t 10 B 6 4 2 0 AUG-01 28 24 22 20 18 ...16 "D ~~14 ~::J 120.r: C-10 8 6 4 1 UPPER MODEL EXT"APOLATION LIMIT CONTROL.L.ING BREACHING DISCHARGE Figure 7-5-18.Time series plots of sockeye salmon spawning WUA as a functi on of rna i nstem di scha rge for the Illonths of August through September,1981,1982,and 1983 for the Slough 9 modelling site. F"" !7-5-29 - - - -~u oo 40 2 ... Cla:...::c<.>... is 20 :E......... Z ~ :E o SEP-30SEP-'!5 60 1981 ~u 0 052 40 .. ... Cla: C[::c<.>... 15 20 :E......... Z C:E 0 SEP-l!5 SEP-30 60 1982 AUG-3'AUG-'6 .2 o AUG-O' SLOUGH 21 SOCKEYE 26 24 22 20 18 ...16 '0<co '4::>ll ~~'2Dt-ID 8 6 4 2 0 AUG-O'AUG-16 AUG-3' 26 24 22 20 18 ...16 'tI<co '4 ::>ll ~~'2D.t: C 10 8 6 ..,..-------------------------r-60 1983 -----------------------/',..., / -~ .u oo 52 40 .=... Cla: C[::c<.> III is 20 :E......... Z ~ :E \IV 6 26 24 22 20 '8 ...'6 'tI <"'4 ::>ll ~~'2D.t: C 10 8 2 o AUG-O'AUG-,6 AUG-3'SEP-'5 o SEP-30 .." UPPER MODEL EXTRAPOLATION LIMIT CONTROLLING BREACHING DISCHARGE Figure 7-5-19.Time series plots of sockeye salmon spawning WUA as a function of mainstem discharge for the months of August through September,1981, 1982,and 1983 for the Slough 21 modelling site..... 7-5-30 UPPER SIDE CHAt\INEL 11 SOCKEYE =., oo S! 40 .. ... '"a:: <I: ::l:r.> UI is 20 ::Ii... l- UIz i ... '"a:: <I: ::l:r.> UI is 20 ::I... l- UI Z C ::I o SEP-30 o SEP-30 o SEP-30 1981 SEP-1S SEP-1S SEP-1SAUG-31 AUG-31 AUG-31 '"'"a:: <I: ::l:-tllbI-...........I~- - - - - -~ is 20 ::I H~~-----,w,-___1 ~ UI Z C ::I AUG-16 . "o ~ 40 .. 1983 AUG-16 1982 . u oo S! 40 .. AUG-16 ..,.------------------------.-60 ..,..------------------------,-60 26 ..,....:------------------------;-60 24 22 18 'ft 16.., ~~14 ~~120 i§.10 8 6 4 2 0 AUG-01 26 24 22 20 18 16 ~.., <co 14~i: ~~120 i§.10 8 6 4 2 0 AUG-01 26 24 22 20 18 'ft 16.., «"14::Ii: ~~120 i§.10 8 6 4 2 0 AUG-01 UPPER MODEL EXTRAPOl.ATION l.IMIT CONTROl.l.ING BREACHING DISCHARGE Figure 7-5-20.Time series plots of sockeye salmon spawning WUA as a function of mainstem discharge for the months of August "through September,1981,1982,and 1983 for the Upper Side Channel 11 modelling site. 7-5-31 SIDE CHANNEL 21 SOCKEYE 26 60 24 1981 ..22 -.. 20 0 0 S!'13 40 ~ -;;-'6 UJ <lI"lII:«c '4::J~-------------<l :E:~~'2 Ucm.<:t:.'0 C 20 :I13UJ ~ 6 m Z 4 ~ :I 2 a 0 AUG-a'AUG-'6 AUG-3'SEP-'5 SEP-30 .-u o ~ 40 .: ... <lI '"<l :E: Um is 20 :I... ~mz:c :I o SEP-30 1982 .-u 0 0 S! 40 .. ... <lI '"<l :E: Um is 20 :I UJ I-mz:c :I 0 SEP-30 1983 160 SEP-Hi SEP-15AUG-31 AUG-31AUG-16 AUG-16 2 a .@OOrxJOOjlomjQOfll:ij;lij:Jcli....I:1oo~WItIJt AUG-01 6l--------------.",.,,~;;::_-_r--'~_j 4 8 2 o AUG-O' 18 16 14 12 10 26 J24 22 20 :'<b 24 22 20 Ie -;;-'6 "~~14 ~~12c.<:t:.10 13 6 4 UPPER MODEL EXTRAPOL.ATION L.IMIT CONTROL.LING BREACHING DISCHARGE Figure 7-5-21.Time series plots of sockeye salmon spawning WUA as a function of mainstem discharge for the months of August through September,1981,1982, and 1983 for the Side Channel 21 modelling site. 7-5-32 i 1 -.-----s -~ SIDE CHANNEL 10 CHUM SALMON SPAWNING 100 ..------------------------------------...--.-120r--- 90 -1 I 110 ---CONTROLUNG MAINSTEM DISCHARGE I 100 BO d 90 .!)f 70 "I fQ1---SITE FLOW AT BO 0 CONTROLUNG DISCHARGE 0 VI~60 I VI~~n ~n 70~1I 155 'tl o::ll 50 O::n 60 814;'1 4;'w~W~0.1Uf-40 1 Uo-50 !!!l4;-4;~u:I u: 0::0::40 I:l 30 I :l VI VI 1!30 20 I 20 I 10 -1 I I I10 B ~~---e-----£I I o I B •I T -I ---,--,I I 0 0 20 40 60 110 100 0 10 20 30 40 SITE FLOW (CPS) UhCU,.I!lQl1d!la -....J MAIN5TE DISCHAR E (CPS) 26 -------26 I c..n 24 ---SITE FLOW AT 24 ---CONTROLLING MAINSTEM I I CONTROLLING DISCHARGE DISCHARGE W 22 22 W I 120120I f 111 -EI f 111 I 0 16 21 0 16 IVI-(/I~ ~n 1 ~n ofl15111415514 o::ll I O::n "I«'12 1 «'12 81w~w~ Uf-I uo-~I4;~10 4;~10u:I u:I0::0:: :l II I :l II VI VI 1 6 I ~6 j/4 I ..4I 2 I 2 Vo -3 ,I I I -0 I , 0 20 40 60 110 100 0 10 20 30 40 SITE PLOW (CPS) (ThoL,H5CmdSa MAINSTEM OISCHAR E (CPS) o GROSS SURFACE AREA o WUA ~CALIBRATION FLOWS (MIN.a MAX.) Figure 7-5-22.Projections of gross surface area and WUA of chum salmon spawning habita t as a function of site flow and mainstem discharge for the Side Channel 10 mode 11 i ng site. 40 4030 ---CONTROLLING MAINSTEM DISCHARGE 20 MAINSTEUh8ISCa~~~w~F.:(CFS) 10 '0 20 30 MA'NSTEUhDt~~~n:~6E (eFS) 11 --~--------=-""::":~ONT~LL1~AINSTEM - ..DISCHARGE 'tl 81~I I I I 1~8~ I I I I I o 20 40 80 60 140 120 100 160 240 220 200 lBO 260 280 320 300 f o "'~~-Il i55It:.«,oWL U~«-... It: :J '" 0 26 24 22 20 f 18 0 16"'-~-ll l:ili 14"'...'12wJ! ~t:.10... '":J 8'"6 4 2 0 0 .---.- 2.4 LOWER SIDE CH AN NEL II CHUM SALMON SPAWNING ._-----_.._.__... 4::~UI gl '" BOOBBBS B 88 BEl I I i I I i I ---SITE FLOW AT CONTROLLING OISCHARGE ......---r-------,---------1 1.2 1.6 2 51~lh~L6:tJnrC~S)0.8 f3BBB8Ei1B B B a-------a------- 0.4 4:1 /_-~_--/---+--------" U ---SITE FLOW AT011CONTROLLINGDISCHARGE ~I I ~I 011~I I I I I V I " I I I I-1---,--L-1'---r ---"T.ft-------r--_-".,m I I ,--~r- 0.4 D.B 1.2 1.6 2 2.4 S,~~n~~~wn?~fS) 320 300 280 260 240 f 220 0 200"'~~. lBOl:i~"'.160..'WJ!140 u~..~,20... '"100:J '"80 60 40 20 0 0 ........26I Ul 24I W 22.;;. 20 f 18 0 16"'~~Il l:ili '4"'...,12wJ!U~10«~... '"8:J '"6 4 2 0 0 o GROSS SURFACE AREA a WUA ~CALIBRATION FLOW Figure 7-5-23.Projections of gross surface area and WUA of chum salmon spawning habitat as a function of site flow and mainstem discharge for the Lower Side Channel 11 modelling site. I J I 1 !j l 1 ~I 1 1 J J J 1 1 1 J ~l J ~-=1 ----1 ---I -==1 ~ SIDE CHANNEL 10 SOCKEYE SALMON SPAWNING 100 ]------_._-------------_.._------~120 110 ---CONTROLLING MAINSTEM90I-------) DISCHARGE 100 60 I -tl 90 t 70 f .:JQI---SITE FLOW A7 60 0 CONTROLLING DISCHARGE 0 III~60 I III~ ~~~~70L5~L5-g ~Io::~50 ~~60 -0:'~IwiIwi50Uf-40 Of-!!!I-0:-I <C~ '""-0:0:40 I:0 30 I :0 III III 30 I20I 1 20 I 10 -j I ::B 10 !~~O+B~:-<r--<J I 0 ,I 0 20 40 60 eo 100 0 10 20 30 40 UhOLJSandS6 ""-J SITE FLOW (eFS)MAINSTE DISCHAR E (eFS) I 26 -.-._---~26 Ul 24 ---SITE FLOW AT 24I ---CONTROLLING MAINSTEM W I CONTROLLING DISCHARGE DISCHARGE2222UlI I2020 t d t I 18 ~I 18 .100 III~16 III~16 '1;1~~I ii."81L5~14 I 14 o:~~~<C,12,12 iltl~I w.l! Uf-I-o:~10 I -o:~10"-"-I0:0: :0 8 I :0 8IIIIII if'"6 I "-g 6 4 I 4 2 "I 2 0 I I I 0 I ,I ,,, 0 4 20 40 60 80 100 0 '0 20 30 40 (fhOLJSand!l6SITEFLOW(CFS),.MAINSTE DISCHAR E (CFS) o GROSS SURFACE AREA o WUA :CALIBRATION FLOWS (MIN.a MAX.) Figure 7-5-24.Projections of gross surface area and WUA of sockeye salmon spawning habitat as a function of site flow and mainstem discharge for the Side Channel 10 modelling site. LOWER SIDE CHANNEL II SOCKEYE SALMON SPAWNING 40 4030 ---CONTROLLING MAINST6M DISCHARGE ---CONTROLLING MAINSTEM DISCHARGE 20 30 MAINSTEUh81~G't'tR6E(CFS\ 20 MAINsTElihDI~c~tR6E (eFS) 10 10 I I £1 01~I "'I I I I l~ I I 1 o o 6 4 2 o I I I I j I I j I 8 10 12 14 18 16 22 20 26 I I 24 80 -----~---~--,--,--"--- 320 --T/-~300 I 280 -nl 260 81 240 ctl f 220 ~I lil-200 1 ~~lBO I~l 160 I..'W~140 I ~t:.120 I ~100 I Ul I "J I40I ,I --------j2~:GBBBe~BBBBiBC i I f o·enL5~It:~..'ow"~~ "-It: i1l 2.4 2.42 ---SITE FLOW AT CONTROLLING DISCHARGE '.82 I -,--I O.B 1.2 1.6 s,~JhFU)~nr~fs) _~---+--_--(l ~---SITE FLOW AT /CONTROLLING DISCHARGE 0.4 I I -til 211 "'I I I I I I I I I I I I o o o J I I I ,- 6 2 4 22 24 -_._-----,26 -,------- 80 1 :!I~I ::ill 1 1 I I I I I 6°L I .~I . 20 !~B ~B ~B?~~~"B JoIIiI-----r-- 0.4 0.8 1.2 1.6 2 SI~l{lf~~~nr~fS) 320~---------,--.'_..-_.. 300 280 260 240 f 220 ~n 200 L5 -g 180 ~~160 wl?140 UI-l!:-120 It: ::J 100 Ul 20 f 18 St-.16- ~~ L5~14 It:~:i 12 ~c.10 '"ii:8 -....,J I U'1 I W 0'1 o GROSS SURFACE MEA o WUA ~CALIBRATION FLOW Figure 7-5-25.Projections of gross surface area and WUA of sockeye salmon spawning habitat as a function of site flow and mainstem discharge for the Lower Side Channel 11 modelling site. ~)J J 1 I )I 1 I I 1 )~J I J ) 1 1 Genera lly,the projections of gross surface area and chum and sockeye spawni ng WUA at the sites whi ch do not currently support chum and sockeye salmon spawning follow trends which are similar to the projections for sites at which spawning has been observed with specific exceptions.Projections of WUA of chum and sockeye salmon spawning habitat at Side Channel 10 are generally lower over the range of flows evaluated than are the WUA projections for the study sites which currently support chum and sockeye sa lmon spawni ng,i ndi cati ng that relatively less usable habitat is available at this study site over the range of flows evaluated.The projecti ons of chum and sockeye salmon WUA at Lower Side Channel 11,however,are generally higher over the range of flows evaluated than for the sites which support chum/sockeye salmon spawning,indicating that relatively more usable spawning habitat is available at this study site over the range of flows evaluated.The reason for this apparent discrepancy is likely linked to the relatively large surface area of this study site.A comparison of the ratio of chum and sockeye salmon spawning WUA to gross surface area at a mainstem discharge of 16,500 cfs (Table 7-5-6)shows that the relative amount of projected chum and sockeye salmon spawning habitat as a function of gross surface area at this study site is low as compared to sites which support chum and sockeye salmon spawning. The time series plots of WUA of chum and sockeye salmon spawning habitat at Side Channel 10 (Figures 7-5-26 and 7-5-27)indicate that projections of WUA of chum and sockeye salmon spawni ng habi tat as a functi on of mainstem discharge follow trends similar to the projections of WUA at sites which .currently support spawning;that is,peaks in WUA occur subsequent to site overtopping by the mainstem.These plots show, however,that the quantity of usable spawning habitat which occurs over the range of discharges which typically occur during the period of peak spawning (August through September)is substantially less.The projections of chum and sockeye salmon spawning WUA over time for Lower Side Channel 11 (Figures 7-5-28 and 7-5-29)may be overestimated due to error involved in inputting upwelling into the model develped for this site.Upwelling at this site was input into the model using limited fi e 1d data and wi nter aeri a 1 photography.Areas of open 1eads not judged (based on discussion with field biologists)to be associated with velocity were assigned upwelling presence codes.As a result,the presence of upwelling at this site was likely overestimated due to assignment of upwelling presence codes to areas of velocity leads, resulting in abnormally high upwelling and WUA projections. To compare the relative amount of projected upwelling area and usable spawning habitat at each study site to the relative spawner use of that habitat,comparisons were made of the ratio of projected upwelling area and chum and salmon spawni ng WUA to gross surface area at each study site at a mainstem discharge·of 16,500 cfs (Table 7-5-6 and Figure 7-5-30 and 7-5-31).These comparisons indicate that sites which have relatively higher upwell ing to gross surface area and WUA to gross surface area ratios generally have relatively higher utilization by spawning chum and sockeye salmon;that is,there appears to be a positive correlation of spawner util ization to area of upwell ing and WUA as indexed by Spearman rank correlation coefficients. 7-5-37 Table 7-5-6.Comparisons of gross surface areas;upwelling areas;upwelling to gross surface area ratios;WUA; WUA to gross surface area ratios;and relative chum/sockeye salmon spawner utilization for modelled study sites at a mainstem discharge of 16,500 cfs. Chum Salmon Sockeye Salmon Gross Upwelling Relative WUA to Relative WUA to Surface Upwelling Gross Area Spawner WUA Gross Area Spawner WUA Gross Area Study Site Ar!a Are~Ratio Utilization (ft2/1000 ft) Ratio Util i zati on (ft2/1000 ft) Ratio (ft )(ft )(%)(116)(116) Slough 8A 68780 12080 18 ++3290 5 +++4450 6 Slough 9 64480 15790 24 ++2370 4 ++5010 8 Slough 21 48140 37960 79 +++5230 11 +++6820 14 Side Channel 10 44520 14630 33 0 00 0 0 0 Lower Side Channel 11 301880 11090 4 0 8060 3 0 5560 2 ........ I Upper Side Channel 11 81320 22830 28 +9210 11 +12130 15(Jl Iw Side Channel 21 157410 9620 6 +3090 2 +2480 2.co - 1/+++High .++Moderate +Low +Absent .1 J ))~~I I ~]~I J ))I SIDE CHANNEL 10 CHUM .:., oo S! 40 .. 1981 ... <:Ia: c( % () f1l is 6 +--------------''"-..:===----------1 20 ~ I- 8 f1l Z 4 ~ 10 12 16 18 14 22 20 26.,.....-------'----------------,-60 24 2 O"""""~~~~.......,,.......-~~~....,.,.......~~~~,......~~~~....,...O AUG-01 AUG-16 AUG-31 SEP-1 S SEP-30 26..,....------------------------,-60 ..-., oo 40 ; 1982 ... "a: c( % () f1l is 8 +-"o;::::----------,..------t----T---1 20 ~ I- f1l Z:;;: 2 6 4 12 10 14 16 16 2 O..y,........~.............~,........~~~~....,...,~-........~...,.I,lT"'"'.......,lI,lI,l~~......,..O AUG-01 AUG-16 AUG-31 SEP-1S SEP-30 24 22 20 "'''.,....----------------------r60 24 22 20 18 1983 ..u oo S!40 .. 4 14 ... <:Ia: c( % () f1l is 8 +----.:V:....-~------r_---120 ~ I-6 f1l Z:;;: 2 16 10 12 2 o I,ll,l[,ll,I.,.~.,J,J.,..,..,..1~~.l,Il,lI,.....,.,.J,J4y.,..,.l,ll,l.,-,.~~~,......~~~~...._+O AUG-01 AUG-16 AUG-31 SEP-15 SEP-30 UPPER MODEL EXTRAPOLATION LIMIT CONTROLLING BREACHING DISCHARGE Figure 7-5-26.Time series plots of chum salmon spawning WUA as a function of mainstem discharge for the months of August through September,1981,1982, and 1983 for the Side Channel 10 modelling site. 7-5-39 LOWER SIDE CHANNEL 1 1 CHUM 26 60 24 1981 22 .:u 20 0 0 18 g 40 .. ~16 1>1ft..,c:> ~i 14 II: C ~~12 :I: 0 <J E.en HI Q 8 20 :I------------'"l- S enz """I 4 :4 i :I 2 0 0 AUG-Ol AUG-16 AUG-31 SEF'-H5 SEF'-30..., 26 60 24 1982 22 .. "20 0 0 18 Q 40 .. 16 -~ "'"..,'"~~14 0:: C~~12 :I:0 <Jf-en10Q S 20 :I '"l- S '"Z 4 :4 :I 2 0 0 AUG-Ol AUG-IS AUG-31 SEF'-lS SEF'-30 26 60 'i 24 1983 !22 .. ';; 20 0 0 ""'t'18 2 ! 40 " 'ii'16 I '"..,'"<c 14 0:::J~C~~12·:I:0 <Jf-'"10 is 20 :IB'"l-e enZ· 4 :4 :I 2 0 0 AUG-Ol AUG-16 AUG-31 SEP-1S SEP-30 UPPER MODEl.EXTRAPOLATION LIMIT CONTROl.LING BREACHING DISCHARGE Fi gure 7-5-28.Time series plots of sockeye salmon spawning WUA as a function of mainstem di scharge for the months of August through September,1981,1982,and 1983 for the Lower Side Channel 11 modell i ng site. ,$'iI~ 7-5-41 "'"' LOWER SIDE CHANNEL 11 SOCKEYE . '; ~ 40 .. ... "II: C:z:u.. is 20 ::E...+-.. Z<::E o SEP-30 1981 8 6 4 2 OJ,..,.~_"""""""""""",,,,,,,~,,,,,,,,,,,,,,l'""""'''''''I,I.,.,.I,Il,II,JI, AUG-01 AUG-16 ....UG-31 SEP-1S 18 16 14 12 10 22 20 26 ~------'-------------------r-1lO 24 ... "II:«:z:u.. is 20 ::E... +- III Z<::E ~u oo Q 40 .. o SEP-30 1982 SEP-15AUG-31AUG-16 6 4 8 2 o .J...~..,.l,II,J.,.I,Jl, AUG-01 12 14 10 18 16 26 ------------------------.-60 24 22 20 - .-"oo Q 40 .. ... "II:«:z:u.. is 20 ::E...+- III Z<::E o SEP-30 1983 SEP-15AUG-31AUG-16 8 2 o..l,..,~~~~~.............~......~......~,..,.l, AUG-01 4 6 22 20 HI 16 14 12 10 26 ------------------------,.60 24 UPPER MODEL EXTRAPOLATION LIMIT CONTROLLING BREACHING DISCHARGE Figure 7-5-29.Time series plots of sockeye salmon spa\iming WUA as a function of mainstem discharge for the months of August through September,1981,1982,and 1983 for the Lower Side Channel 11 modelling site. 7-5-42 CHUM 80 •SLOUGH 21 0-1..--...,.-...,.-...,.-.,......__ 40 20 +-t-+ G3} •UPPER SIDE CHANNEL II •SLOUGH 9 •SLOUGH SA ++ (2) + (I) •SIDE CHANNEL 10 •SlOE CHANNEL 21 •LOWER SIDE CHANNEL II o CO} <UJa:::« ~60oa:: (!) o I- (!) z :J ...J UJ 3:a.. ::) ~o o ~a:: ."""1 I 1 [2 2 6 8 •SLOUGH 21 •SLOUGH SA •SLOUGH 9 •UPPER SIDE CHANNEL II •LOWER SIDE CHANNEL II •SlOE CHANN EL 21 4 <UJ a:::10< en (J)oa::: (!) o.... <t :;:) 3: ~o o .... <t a: "'l' :I o-'-__.....;S;,;;IO:;,;E;;..;;C;,;,,;H;,;,,;A~N~N_=E_=L..:IFO------r__-----__-- o ++ ++++ (O)(1 )(2)(3) RELATIVE CHUM SPAWNER UTILIZATION Figure 7-5-30.Comparisons of the ratio of upwelling area and chum salmon spawning WUA to gross surface area at modelled study sites projected at a mainstem discharge of 16,500 cfs for each of the modelled study sites (See Table 7-5-6 for key to spawner utilization);r s =Spearman rank correlation coefficient. 7-5-43 SOCKEYE - •SLOUGH 8A •SLOUGH 21 •SlOE CHAN NEL 21 •SIDE CHANNEL 10 •UPPER SIDE CHANNEL \I •SLOUGH 9 •LOWER SIDE CHANNEL 11O-L.._.....,.~.::::.:.:.:.::.::.::.~--r------r-----~-- 20 80 40 « UJa:« enen 60oa: C) 12 C) Z ...J ...J U.I 3=a. ~ lJ..o o ~a: o (0) + (1) ++ (2) +++ (3) ~:, •LOWER SIDE •SlOE CHANNEL 21 CHANNEL II SIDE CHANNEL \0 «16 UJa::14« en 12en 0a::10C) 0 l-S « ~63= lJ..40 0 21-.«a::0 •UPPER SIDE CHANNEL II •SLOUGH 9 •SLOUGH 21 •SLOUGH 8A ~J o ++++++ (0)(I)(2)(3) RELATIVE SOCKEYE SPAWNER UTILIZATION Figure 7-5-31.Comparisons of the ratio of upwelling area and sockeye spawning WUA to gross surface area projected at a mainstem discharge of 16,500 cfs for each of the modelled study sites (See Table 7-5-6 for key to spawner utilization);rs =Spearman rank correlation coefficent. 7-5-44 - 5.4 Discussion 5.4.1 Assumptions used in the Application of the Habitat Simulation Models Weighted usable area,as used in this report,is a habitat index of the capacity of a site to support chum or sockeye salmon spawning.Several underlying assumptions are made in calculating WUA using the IFIM study approach (Orth and Maughan 1982).In regard to this study these assumptions may be stated as follo~s: 1)Depth,velocity,substrate,and upwelling are the most important habitat variables affecting chum and sockeye salmon spawning under varying flow conditions; 2)Depth,velocity,substrate,and upwelling independently affect the selection of spawning by chum and sockeye salmon; 3)The channel of the study site is not altered significantly by the ranges of flow modelled; 4)The study reach can be modelled by evaluating selected study transects;and, 5)There is a positive correlation between WUA and habitat use. , The first assumption is difficult to evaluate since flow related changes at a study site may have significant effects on many interrelated habitat conditions used for spawning.In the derivation of WUA,it is as.sumed that the usability of spawning habitat within a site can be accurately indexed if all the variables affecting spawning are known. Since this is not l'ikely,we have identified four habitat variables which appear to be most critical for spawning at the sites.Other habitat variables,notably water quality and temperature,may also potentially affect the spawning usability of a site,but are believed to exert only a limited influence on chum and sockeye salmon spawning in sloughs and side channels of the middle Susitna River under current conditions.For these reasons,these first assumptions appears justified for all of the study sites evaluated with the exception of Side Channel 10 and Lower Side Channel 11,where it is believed that some other habitat variable is limiting spawning. It is questionable whether the four habitat variables evaluated are of equal relative importance as critical habitat vari abl es affecti ng the selection of spawning areas by chum and sockeye salmon in sloughs and side channels of the middle Susitna River.Assuming passage depth requirements are met,the presence or absence of upwelling appears to be the key habitat variable affecting selection and utilization of spawning areas by chum and sockeye salmon.This especially apparent in slough habitats,where the available depth,velocities,and substrates are often suitable for spawning,but where spawning is only observed to occur in areas of upwelling.It is less apparent in side channels habitats where unsuitable depth,velocity,or substrates may make 7-5-45 upwelling areas unsuitable spawning habitat.This is evident in a review of ratios of upwelling area to gross surface area and WUA to gross surface area at the slough and side channel study site.The difference in these ratios shows that not all areas of upwelling in sloughs or side channels provide usable habitat for chum and salmon spawning (e.g.,Side Channel 10).This indicates that although upwelling is a key habitat variable affecting selection of spawning areas,that other habitat variables ultimately determine the overall suitability of an upwelling area for spawning. As discussed in Section 4.0,the second assumption also appears to be justified;that is,depth,velocity,and substrate appear to act as independent variables in the selection of spawning sites by salmon.It is not possible to analyze the relationship of depth,velocity,or substrate to upwelling due to the limited nature of the upwelling data. However,since upwelling was assigned using a binary approach, only the other three habitat variables impact WUA (and thus spawner utilization)when upwelling is present.Therefore,correlation between the other three habitat variables and the two upwelling variables (i.e., absent or present)would not impact WUA projections.Such correlation is accounted for in the "counting"of the other three habitat suitability factors if upwelling is present and the "discounting"of them if upwelling is absent. The third assumption also appears justified on a general level.Channel geometry and morphology at each of the study sites remained relatively stable during the period of study although specific changes in channel geometry and morphology did occur.For example,large amounts of silt were deposited along two transects in the Slough 9 modelling study site during a flood event in September of 1982.Such changes show that both short and long term changes in channel geometry and morphology on a site-specific basis are possible.However,such changes probably refl ect a dynami c,but genera lly stable equ i 1i bri urn and are therefore believed to exert only a limited influence on the long-term habitat availability within the system. Transects that were both cri ti ca 1 in terms of spawni ng and representative in terms of habitat usability were selected for evaluation at each study reach.For this reason,the results from the transects sampled are believed to be representative of the associated study reach and the fourth assumption appears justified.The issue of overall study site representativeness is addressed in Sections 2.3 and 5.4.3. The fifth assumption also appears to generally hold true.Based on cornpari sons of rel ative spawni ng habitat usabil ity to spawni ng utilization at modelling study sites (Figure 7-5-30 and 7-5-31),there appears to be a positive relationship between projected WUA and habitat use at study sites;that is,sites with relative high utilization by spawning chum and sockeye salmon (e.g.,Sloughs 21 and SA)exhibit higher projected WUA to gross surface area ratios than do sites with little or no spawner utilization (e.g.,Lower Side Channel 11 and Side Channel 10). 7-5-46 .... I I I ,~ In summary,the inherent assumptions of the IFIM study approach of habitat analysis as applied in this study appear generally justified although specific assumptions were violated under isolated conditions. The extent to which the effects of such violations biased our results is difficult to evaluate;however,it is believed that such violations exerted only limited influence. 5.4.2 Weighted Usable Area Projections WUA projections at slough and side channel study sites generally exhibit similar trends for chum and sockeye salmon spawning habitat as a function of site flow and mainstem discharge with one notable exception: due to higher controlling discharges in sloughs,spawning WUA's peak at higher mainstem discharges in slough habitats than in side channel habitats which were modelled.Chum and sockeye salmon spawning WUA projections also generally follow similar trends among study sites,with the excepti on that WUA of sockeye salmon spawni ng habitat typi ca lly peaks at lower mainstem discharges than do the WUA projections for chum salmon spawning habitat.The reason for this is that velocities become limiting to sockeye salmon spawning at lower mainstem discharges than they do for chum salmon spawning (see Section 4.0)• Weighted usable area projections of chum and sockeye salmon spawning habitat in modelled sloughs and side channels in the middle reach of the Susitna River generally peak at mainstem discharges ranging from 20,000 to 35,000 cfs.The controlling factor appears to be the overtopping of the sites by mainstem discharge and the subsequent controlling of the site flows by mainstem discharge.If it is assumed that these modelled sloughs and side channels are representative of other non-modelled sloughs and side channels in the middle reach which currently support spawning,than the theoretical maximum spawning WUA for slough and side channel habitats in the middle river reach would occur slightly after the mainstem discharge overtops and controls the hydraulics at a maximum number of these habitats. Although peak WUA projections of chum and sockeye salmon spawning habitat in modelled sloughs and side channels generally occurs at mai nstem di scharges in the range from 20,000 to 35,000 cfs,typi ca 1 mainstem discharges during the period of peak spawning activity (August through September)are much lower such that peak WUAls values are only rarely attained.Average monthly discharges based on the historical discharge record for the months of August and September are 22,000 and 14,000 cfs,respectively.As a result,the actual WUA of spawning habitat is much lower at study sites duri ng the range of mai nstem discharges typically present during the period of peak spawning.Sites which have relatively low controlling discharges (Slough 9 and Side Channel 21)typically have observed maximum WUA values which more closely approximate the theoretically predicted maximum WUA values than do sites with higher controlling discharges (Slough 8A). Based on a review of the time series plots,flows at study sites which currently support chum and sockeye salmon spawning are only infrequently controlled by mainstem discharge.For this reason,the actual usable 7 --5-4 7 area of chum and sockeye salmon spawning habitat at study sites remains relatively low and stable during the period of peak spawning activity (August through September),except during flood events. Projections of WUA of chum and sockeye salmon spawning habitat were also made for the two study si tes whi ch do not currently support chum and sockeye salmon spawning.With specific exceptions,these projections follow similar trends as do the projections for sites which currently support chum and salmon spawning.A review of the WUA time series plots for these sites indicates,however,that flows at these study sites rarely provide a significant quantity of usable spawning habitat at the study sites,causing the actual usable area of chum/sockeye salmon spawning habitat at these sites to be extremely low during the period of peak spawning activity.Such sites may represent other "low-quality" slough and side channel habitats of the middle river reach. In summary,WUA projections for chum and sockeye salmon spawning habitat in sloughs and side channels exhibit certain species-specific and habitat-specific trends.It should be stressed,however,that the projections of spawning WUA must be carefully evaluated in conjunction with other conditions at the site as is discussed below in order to determine their overall utility as an index of spawning habitat usability. 5.4.3 Recommended Applications and Limitati'ons of the Data The WUA projections developed in this report represent a synthesis of our current understanding of the relationship between usable spawning habitat (as indexed by WUA)and flow/discharge within several modelled slough and side channel study sites.As used in this report,WUA is a habitat index of the capacity of a site to support chum or sockeye salmon spawning.As such,it only represents an index of the relative usability of potential spawning habitat at a site in terms of four selected habitat variables (depth,velocity,substrate,and upwelling). It does not represent and should not be used as an est"imate of fish numbers or production at a site,nor as a confirmation that fish will util ize an area projected as being suitable for spawning at a study site. Because of this,application of the WUA projections to describe usable spawni ng habitat at study sites must be done on a case-by-case basi s during which other variables influencing the habitat are considered. For example,WUA indices are only valid for the species evaluated if all other required habitat conditions,such as temperature or water quality, at the site are also within acceptable ranges.Additionally,the various habitat variables affecting other 1ife stages (i .e.,passage, incubation,and rearing)affecti ng overall reproducti ve success of the species under study must also be considered (Withler 1982). A better understanding of the relationship between unbreached mainstem discharge conditions and slough flows,including the relative contribution of various water sources (e.g.,groundwater upwelling, seepage,and surface waters)to slough and side channel flows are also 7-5-48 '"'" - - _. - ..... ,1""'\ I ! """ needed.Frequency analysis of local flows and better quantifications of upwelling conditions are also recommended.Further,a better understanding of the influences of backwater on these analyses is required.For these reasons,the WUA projections presented in this report should not be the sole describing factor used to evaluate the relative usability of chum/salmon salmon spawning habitat conditions at modelled study sites. Application of these WUA projections to areas outside of modelled areas of study sites must be approached with caution.For example,although it is likely that the WUA projections presented in this section can be extrapolated to areas outside of the modelled areas of study sites and to other non-modelled sloughs and side channels in the middle reach of the Susitna River that currently support spawning,it must first be determined whether the underlying assumptions used in the derivation of the projections can be applied to such non-modelled habitats.Prior to such uses,it is recommended that additional field data be collected to justify the application of the WUA projections to such other non-modelled habitats. 7-5-49 ,~ I""t I T 6.0 SUMMARY This chapter presents an evaluation of the suitabil ity of selected slough and side channel habitats of the middle reach of the Susitna River for spawning by chum and sockeye salmon as a function of flow. Section 1.0 described the rationale and objectives of this evaluation. as well as a general description of the Instream Flow Incremental Methodology (IFIM)study approach used in this evaluation. Section 2.0 described the general concepts and rationale used in the selection of slough and side channel study sites.Three sloughs (8A.9 and 21)and four side channels (l0,lower and Upper 11.and 21)were selected for evaluation.Additionally,the representativeness of selected study sites were discussed and general descriptions of selected study sites were presented. Section 3.0 described the data collection and analysis required for the development of hydraulic simulation models for the three sloughs and four side channels selected for evaluation.Ten hydraulic simulation models were calibrated to simulate depths and velocities associated with a range of si te-speci fic flows at the seven study sites.Compari sons between corresponding sets of simulated and measured hydraulic parameters indicate that the models provide reliable estimates of depths and velocities within their recormnended calibration ranges. Section 4.0 presented the habitat util ization data col.lected for chum and sockeye sa lmon spawni ng ins1oughs and side channe 1sin the mi dd 1e river reach and the methods used to analyze the data to develop spawning habitat suitabil ity criteria.The habitat suitabil ity criteria were developed for the habitat variables of depth,velocity,substrate,and upwelling for input into the habitat simulation models discussed in Section 5.0.The spawning suitability criteria developed for chum salmon were based on an analysis of utilization data as modified using limited preference data,literature information,and the opinion of project biologists.familiar with middle Susitna River chum salmon stocks.The spawning suitability criteria developed for sockeye salmon were developed using the same analytical approach used in the chum salmon analysis with the exception that no analysis of preference could be made due to the lack of concurrently collected availabi 1ity/uti Hzation data. Section 5.0 presented a discussion of the linking of the hydraulic simulation models (developed in Section 3.0)with the spawning habitat suitability criteria (developed in·Section 4.0)usin9a habitat simulation model (HABTAT)to project weighted usable area {WUA)of chum and sockeye salmon spawning habitat as a function of flow for the modelled study sites.Using these relationships and relationships between site flows and mainstem discharge presented in Chapter 1 of this report,the relationships between chum and sockeye salmon spawning habitat as a function of mainstem discharge for the period of controlled site flows were also determined for each modelled study site.These projections of chum and sockeye spawning WUA made at study sites 7-6-1 indicate that spawning habitat in sloughs and side channels exhibits certain species-specific and site-specific trends.Generally, projections of WUA at study sites peak in the range mainstem discharges from 20,000 to 35,000 cfs,with the controlling factor appearing to be the overtopping of the site by mainstem discharge and the subsequent control of the site flow by mainstem discharge.Assuming that the modelled sloughs and side channels are representative of other non-modelled sloughs and side channels in the middle reach which currently support spawning,the theoretical maximum WUA for slough and side channel habitats in the middle river reach would occur slightly after the mainstem discharge overtops and controls the hydraulics at a maximum number of these habi tats.Based on a revi ew of time seri es plots of WUA overtime of each study site,however,flows at study sites which currently support chum and sockeye spawning are only infrequently controlled by mainstem discharge.For this reason,the WUA at study sites remains relatively low and stable during the period of peak spawning activity (August through September),except during flood events.There appears to be a general positive correlation between projected WUA and habitat use at study sites. In conclusion,the IFIM study approach was used to successfully evaluate the suitability of selected slough and side channel habitats of the middle reach of the Susitna River for spawning by chum and sockeye salmon as a function of flow.Conditions whi~h should be satisfied prior to application of these data are also discussed in each respective section. 7-6-2 - - "i I """:, 7.0 GLOSSARY Availability Data:Data collected,or synthesized by a computer model, which represents the range and frequency of selected environmental conditions present which are available to be used by a particular species/l i fe phase. Best Curve:Utilization curve,usually with grouped increments,which represent the distribution with the least variability,lowest level of irregular fluctuations,minimal peakedness,and minimal coefficient of variation. Binary Criteria:Evaluation of the suitability of a particular habitat component for a selected species/life phase using only two (b.inary) options (e.g.,present to absent).. Breaching:The overtopping of the head of a side channel or side slough by the mainstem river (also called overtopping). Cell:The surface area surrounding each vertical between adjacent -verti ca 1s and transects whi ch is·assumed to have the same habitat characteristics as the vertical at the center of the cell. Coefficient of Variation:The sample standard deviation divided by the sample mean. Computer Models:See PHABSIM,IFG-2 (WSP),IFG-4,HABTAT. Controlling Discharge:The mainstem discharge at Gold Creek required to directly govern the hydraulic characteristics within a side slough or side channel. Critical Reaches:Sites at which microhabitat characteristics are generally atypical of the microhabitat in the associated river segment.The two criteria used to define a critical reach are: .1.The microhabitat characteristics of the critical reach are controlling or limiting to the evaluation species (such as limiting migration or spawni ng);and 2.These microhabitat characteristics are unavailable or in short supply in the representative reaches. Curve Types:See spawning habitat curve types. Data Tbpes:See availability data,utilization data,measured data, o served data,synthetic data,predicted data,and forecast. Discharge:Water volume passing a fixed point per unit time.In this report,the term specifically refers to mainstem habitat. Elevation of Zero Flow~The streambed elevation of a hydraulic control at which no flow occurs.See also point of zero flow. 7-7-1 GLOSSARY (continued) Fish Curve:Generic name,used interchangeably with habitat curve, applied to suitability/preference/utilization curves for fish;see also habitat curve. Flow:The movement of a volume of water from place to place passing a --fixed point per unit time.In this report,the term specifically refers to non-mainstem habitats. Forecast:Trend or conclusion drawn from the interpretation of predicted valu~s. Habitat:The surroundingen¥irOnmental conditions to which a particular species and life stage of fish responds both behaviorally and physi ologica lly. Habitat Curve:Generic name,used interchangeably with fish curve, applied to suitability/reference/utilization curves for fish;see also fish curve. Habitat Variable:One element of the total spectrum of elements (physical and chemical conditions)needed to support the life functions of a particular species and life stage (e.j.,streamflow, channel geometry,depth,velocity,substrate,upwelling,etc.). HABTAT:A computer model which is part of the IFG's PHABSIM model used to combine hydraulic models output and suitability criteria curves in order to determine habitat usability (weighted usable area)for a particUlar species and life stage of interest. Hydraulic Control:A channel section with a specific relationship between stage and discharge. IFG:Cooperative Instream Flow Service Group of the United States Fish and Wildlife Service. IFG-2 Model:A computer model based on theory used to simulate hydrau li c condit ions wi thin a study site.The mode 1 is ca 1i bra ted using a minimum of two or preferably three or more sets of hydraulic measurements. IFG-4 Model:A computer model based on empirical data used to simulate hydraulic conditions within a study site.The model is calibrated using a minimum of two or preferably three or more sets of hydraulic measurement. Initial Breachin~Discharge:The mainstem discharge at Gold Creek (USGS gaging statlon #152~2000)which represents the initial point when mainstem water begins to enter the upstream head (berm)of a side slough or channel. 7-7-2 4 mAN q "'"'!, ~, .GLOSSARY (continued) Joint Preference Factor (JPF):A function which quantifies a species preference or tolerance for combined suitability criteria (e.g., combined veloc.ity,depth,substrate,and upwelling suitability criteria). Maximum GrOU¥ed Value:The x-value associated with the increment in a scaled requency histogram plot which has an associated y-value of 1.0;that is,the increment with the maximum scaled frequency. Measured Data:Values derived through the process of obtaining a direct measurement. Middle Reach (of the SusHna River):The segment of the Susitna River between the Chulitna River confluence and Devil Canyon. Minimal Irregular Fluctuations:Grouped values in a frequency histogram plot should continu.al1y increase to the maximum grouped value,then continually decrease,as defined by a series of four indices proposed by Baldridge and Amos (1982).. Minimal Peakedness:Meaning a minimal difference between the maximum grouped value (i.e.,.increment 0 and the increments immediately below and above the maximum,as defined by a peakedness index. Minimal Sample Variance:The condition of a minimal variability in the frequency counts used to denote a nbest curve n •. Observed Data:Values derived through a visual estimate or evaluation. Peakedness Index:A measure of the di fference between the maximum grouped value or increment (e.g.,in a scaled frequency histogram plot)and the increments to either side of the maximum grouped value or increment.The index ranges from zero,indicating no peak,to two,indicating a maximum peak. Physical Habitat Simulation Model (PHABSIM):A collection of computer models,developed by the Cooperative Instream Flow Service Group of the USFWS (IFG),used to simulate hydraul ic habitat conditions for fish,benthic invertebrates,and recreational value. Point of Zero Flow:The 1ocati on along the thalweg where no flow occurs.See also elevation of zero flow. Predicted Data:Individual numbers or'sets of numbers that result from a computer model simulation run. Preference:An apparent behavioral selection for a particular habitat component value as indicated by observed or measured data. 7 7-3 GLOSSARY (continued) Preference Curve:A utilization curve modified to account for selection of a particular value within the available range of habitat conditi ons.Preference curves can be constructed by divi di ng the utilized values by values of available habitat in each increment. The x and y axes are established in the same manner as the utilization curves. Representative Reaches:Sites selected through a random or uniform sampling process which are used to describe the typical microhabitat in a segment. Scaled Frequency:The label for the y-axis indicating data which has been standardize to a 0 to 1 scale. Side Channel Habitat:Consists of those portions of the Susitna River that normally convey water during the open water season but become appreciably dewatered during periods of low mainstem discharge. Si de channel habitat may exi st either in we 11 defi ned overflow channels,or in poorly defined reaches flowing through partially submerged gravel bars and islands along the margins of the mainstem river.Side channel streambed elevations are typically lower than the mean monthly water surface elevations of the mainstem river observed during June,July,and August.Side channel habitats are 'characterized by shallower depths,lower velocities,and smaller streambed materials that the adjacent habitat of the mainstem ri ver. Si de Slough Habi tat:These habitats are located in overflow channels between the edge of the floodplain and the mainstem and side channels of the Susitna River.They are usually separated from the mainstem and/or side channels by well vegetated bars.An exposed alluvial berm often separates the head of the side slough from mainstem discharge or side channel flows.The controlling streambed/bank elevations at the upstream end of the side sloughs are sl ightly less that the water surface elevations of the mean monthly discharges of the the mainstem Susitna River observed for June,July,and August.At intermediate and low-side charge periods,the side sloughs convey clear water from small tributary and/or upwelling groundwater.These clear water inflows are essential contributors to the existence of this habitat type.The water surface e 1evati on of the Sus itna Ri ver generally cau ses a backwater area to extend well up into the slough from its lower end.Even though this substantial backwater area exists the sloughs function hydraulically very much like small stream systems and several hundred feet of the slough channel often conveys water independent'of mainstem backwater effects.At high discharges the water surface elevations of the mainstem river is sufficient to overtop the upper end of the slough.Surface water temperatures in the side sloughs during summer months are principally a function of air temperature,solar radiation,and the temperature of the local runoff. 7-7-.4 .... --I GLOSSARY (continued) Spawning Habitat Curve Types:See utilization curve,preference curve, suitability criteria curve,habitat curve,and fish curve. Suitability:How well a particular habitat condition meets the life stage needs of a particular species. Suitability Criteria Curve:A utilization or preference curve,modified by additional information (e.g.,observations,professional judgement,field and literature data,etc.)to represent the suitability of habitat for a particular species and life/stage over the range of habitat components expected to be encountered.The x and y axes are established in the same manner as the utilization curves. Suitability Curve:See suitability criteria curve. Suitability Index:The label for the y-axis indicating standardization to the 0 to 1 scale for a suitability curve.Suitability index can also be used to denote a value determined from a suitability curve. Syntheti c Data:Estimated data sets based on professi ona 1 judgement used in the hydraulic modeling calibration process to fill indata gaps. Utilization Curve:Habitat data (e.g.,depth,velocity,substrate, upwelling,etc.),collected during selected periods of life stage activity (i.e.,passage,spawning,incubation,and rearing)plotted to show distribution of actual field measurements.The scale on the x-axis corresponds to the accuracy of the measuring device and is often grouped into increments to smooth the distribution.The relative number of observations representing each increment is standardized to a 0 to 1 scale by setting the largest increment to 1 and dividing each increment by this maximum to assign a proportional value. Utilization Data:Data collected at an active life stage site (e.g., depth,velocity and substrate data collected at an active salmon redd)• Velocity Adjustment Factor (VAF):The ratio of predicted to observed (input)discharges computed for an IFG-4 hydraulic model.The IFG considers a model acceptably calibrated when the VAF is between 0.9 and 1.1. Vertical:The point on a transect where a measurement is made (the measurement is perpendicular to the horizontal plane defined by the water surface). Water Surface Profile (WSP)Model:See IFG-2 Model. 7-7-5 Weighted Usable Area (WUA):An index of the capacity of a site in terms of both quantity and quality of habitat to support the species a~d life stage being considered.WUA is expressed as square feet (ft ) or percentage (%)of wetted surface habitat area predicted to be available per 1,000 linear feet of habitat reach at a given flow. 7·7.-6 ~, - """1' I ! ..,. ! I ,.,.. .... GLOSSARY OF SCIENTIFIC NAMES Sci entifi c Name Oncorhynchus keta (Welbaum) Oncorhynchus nerka (Walbaum) 7-7-7 Common Name Chum salmon Sockeye salmon 8.0 CONTRIBUTORS Aquatic Habitat and Instream Flow Studies (AH)Project Leader and Principal Contact AH Fish Habitat Utilization Subproject Leader Hydraulic Engineering Data Processing Project Leader Data Reduction and Graphics Coordinator Graphics Typing Staff Editors Data Collection Data Analysis Physical Modelling 7-8-1 Christopher Estes Andrew Hoffmann E.Woody Tri hey &Associates Allen E.Bingham Camille Stephens Sally Donovan Carol Hepler Carol Kerkvliet Ann Reilly Vicki Cunningham r~ary Gressett Bobbie Sue Greene Doug Vincent-Lang Allen E.Bingham Christopher Estes Andrew Hoffmann Cleve Steward Steve Cruml ey Jeff Blakely Christopher Estes Diane Hilliard Andrew Hoffman Issac Queral Sheryl Salasky Gene Sandone Joe Sautner Don Seagren Kathy Sheehan Rick Sinnot Kim Sylvester Woody Trihey Len Vining Diane Hilliard Kim Syl vester Woody Trihey Allen E.Bingham CONTRIBUTORS (continued)-Fish Habitat Criteria Analysis Allen E.Bingham Doug Vincent-Lang Christopher Estes ~Andrew Hoffmann Weighted Usable Area Analysis Doug Vincent-Lang A11 en E.Bingham -, Christopher Estes Andrew Hoffmann ~ Text Physical Modelling Diane Hilliard E.Woody Trihey ~ Allen E.Bingham Fish Habitat Criteria Allen E.Bingham ~ Doug Vincent-Lang Christopher Estes Andrew Hoffmann ~Cleve Steward Steve Crumley Usable Habitat Analysis Doug Vincent-Lang Allen E.Bingham Christopher Estes Andrew Hoffmann ~ Cleve Steward Steve Crumley - WM'. 7-8-2 I'''''' .i 9.0 ACKNOWLEDGEMENTS The authors express their appreciation to the following for their assistance in preparing this report: The other ADF&G Su Hydro Aquatic Studies Program staff who provided their support to this report.Special appreciation is extended to T.Quane and the Instream Flow Evaluations study team for assisting with the data collection and analyses processes. D.Amos,ADF&G Sport Fish/Biometrics,for her assistance in developing the analytical approach for the suitabil ity criteria curves. 7-9-1 """' r 10.0 LITERATURE CITED Alaska Department of Fish and Game (ADF&G).1974.An assessment of the anadromous fi sh popul ati ons in the upper Sus itna Hi ver watershed between Devil Canyon and the Chulitna River.Alaska Department of Fish and Game.Anchorage,Alaska. ·1976.Fish and wildlife studies related to the Corps of --Engineers Devil Canyon,Watana Reservoir Hydroelectric Project. Alaska Department of Fish and Game.Anchorage,Alaska. ·1977.Preauthorization assessment --Hydroelectric Projects:preliminary quality and aquatic species composition. and Game.Anchorage,Alaska. of the proposed Susitna investigations of water Alaska Department of Fish """ .., I ·1978.Preliminary environmental assessment of hydroelectric -development on the Susitna River.Alaska Department of Fish and Game.Anchorage.Alaska. 1981a.Phase 1 final draft report.Volume 1.Subtask 7.10. Aquati c Habi tat and Instream Flow Project.Al aska Department of Fish and Game.Anchorage,Alaska. 1981b.Phase 1 final draft report.Volume 2.(2 parts). Subtask 7.10.Aquatic Habitat and Instream Flow project.Alaska Department of Fish and Game.Anchorage.Alaska. _._._1982.Phase 1 final draft report.Subtask 7.10.Aquatic studies program.Alaska Department of Fish and Game.Anchorage, Alaska. •1983a.Susitna Hydro aquatic studies phase II basic data report. -Volume 4 (3 parts).Aquatic habitat and instream flow studies, 1982.Alaska Department of Fish and Game.Anchorage,Alaska. ·1983b.Susitna Hydro Aquatic Studies Phase II Report.Synopsis --of the 1982 aquatic studi es and ana lysi s of fi sh and habitat relationships (2 parts).Alaska Department of Fish and Game.Susitna Hydro Aquatic Studies.Anchorage.Alaska. Amos.D.1984.Personal Communication,Alaska Department of Fish and Game.Sport Fish/Biometrics Division.Anchorage,Alaska. Baldridge.J.E.and D.Amos.1982.A technique for determining fish habitat suitabil ity criteria:a comparison between habitat and utilization and availability.Paper presented at the symposium on Acquisition and Utilization of Aquatic Habitat Inventory Information.Sponsored by American Fisheries Society.Oct.28-30, 1981.Portland.Oregon. Baldridge,J.E.and E.W.Trihey,1982.Potential effects of two alternative hydroelectric developments on the fisherey resource of the lower Tazimina River,Alaska.Arctic Environmental Information and Data Center.Anchorage,Alaska. 7-10-1 LITERATURE CITED (continued) Barrett,B.M.,F.M.Thompson,and S.N.Wick.1984.Adult Anadromous Fish Investigations:fo.1ay-October 1983.Alaska Department of Fish and Game Susitna Hydro Electric Studies.Anchorage,Alaska. - - Beauchamp,D.A.,et ale 1983. environmental requirements USFWS.Washington,DC. Species profiles:Life histories and (Pacific Northwest),chinook salmon. Bovee,K.D.and T.Cochnauer.1977.Development and evaluation for we.ighted criteria,probability-of-use curves for instream flow assessments:fisheries.Instream Flow Information Paper No.3. Instream Flow Service Group.USFWS.Ft.Collins,Colorado. ·ann R. -studies: No.5. Colorado. Milhous.1978.Hydraulic simulation in instream flow theory and techniques.Instream Flow Informati on Paper Instream Flow Service Group.USFWS.Ft.Collins, ·1982.A guide to stream habitat and analysis using instream flow -incremental methodology.Instream Flow Informati on paper No.12. Coop.Instream Flow Service Group.USFWS.Colorado. Brown,M.B.,and A.B.Forsythe.1974.Robust tests for the equal ity of variances.Journal of the American Statistical Association. 69:364-367. Buchanan,T.J.,and W.P.Somers.1969.Techniques of water resources investigations of the United States Geological Survey.Chapter AS. Discharge measurements at gaging stations.USGS.Washington DC. Estes,C.C.,K.R.Hepler and A.G.Hoffmann.1981.Willow and Deception Creeks instream flow demonstration study.Vo1.1.Prepared for the U.S.Department of Agriculture,Soil .bonservation Service, Interagency Coop.Susitna River Basi n Study.Al aska Department of Fish and Game.Habitat and Sport Fish Divisions.Anchorage, Alaska. Dixon,W.J.,and F.J.Massey,Jr.1969. analysis.McGraw-Hill Book Company. Introduction to statistical New York,New York.- •D.S.Vincent-Lang,(eds.)1984.Aquatic Habitat and Instream Flow --Investigations.Alaska Department of Fish and Game.Su Hydro Aquatic Studies Report Series No.3.Alaska Department of Fish and Game.Anchorage,Alaska. 7-10-2 r- ! - ..... .-. LITERATURE CITED (continued) Francisco,K.1976.First interim report of the Commercial Fish-Technical Evaluation study.Joint State/Federal Fish and Wildlife Advisory Team.Special Report No.4.Anchorage,Alaska. Glaser,R.E.1983.Levene1s robust test of homogeneity of variances. In S.Katz and N.L.Johnson,editors.Encyclopedia of statistical sci.ences,Volume 4.Pages 608 -610.John Wiley and Sons.New York, New York. Hale,S.S.1981.Freshwater habitat relationships:chum salmon (Oncorhynchus ketal.Alaska Department of Fish and Game.Habitat Division.Resource Assessment Branch.Anchorage,Alaska. Instream Flow Group (IFG).1980.The incremental approach to the study of instream flows.USFWS.W/IFG-8)W31.Ft.Collins~Colorado . Kleinbaum,D.G.and L.L.Kupper.1978.Applied Regression Analysis and other Multivariable Methods.Duxbury Press.North Scituate~ Massachusettes. Kogl ~D.R.1965.Springs and grounwater as factors affecting survival of chum salmon spawn in a sub-arctic stream.M.S.thesis. University of Alaska.Fairbanks,Alaska~ Krueger,S.W.1981.Freshwater habitat relationships:pink salmon~ (Oncorhynchus gorbuscha).Alaska Department of Fish and Game. Habitat Division.Resource Assessment Branch.Anchorage~Alaska . Levanidov,V.Y.1954.Ways of increasing the reproduction of American chum salmon.(Transl.from Russian).Akademiya.Nauk SSSR, Ikhtiologicheskaya Komissya,Trudy Soveschanii,~lo.4:120-128.Israel Program for Scientific Translations.Cat.No.8.Office of Tech. Service.U.S.Dept.of Commerce.Washington,D.C. McMahon~T.E.1983.Habitat suitability index models:coho salmon. USFWS.Fort Co 11 ins,Colorado. Milhous,R.T.,D.L.Wegner,and T.Waddle. physical habitat simulation system. Paper No.11.Report FWS/OBS 81/43. USFWS.Washington DC. 1981.User 1 s guide to the Instream Flow Information Instream Flow Service Group. Ott;L.1977. analysis. An introduction to statistical methods and Duxbury Press,North Scituate,Massachusetts,USA. data Orth,D.J.and D.E.Maughan.1982.Evaluation of the incremental methodology for recommending instream flows for fishes. Transactions of the American Fisheries Society.111:413-445. Prewitt,C.G.1982.The effect of depth-velocity correlations on aquati c phys i ca 1 habitat usabil ity estimates.PhD di ssertati on, Colorado State University,Fort Collins,Colorado.83 pp. 7-10-3 LITERATURE CITED (continued) R&M Consultants,Inc.1982.Alaska Power Authority Susitna Hydroelectric Projects;task 2 -surveys and site facilities;1982 hydrographic surveys.Report for Acres American Inc.Anchorage, Alaska. Reiser,D.W.and T.A.Wesche.1977.Determination of physical and hydraulic preferences of brown and brook trout in the selection of spawning locations.Water resources Series No.64.Water Resources Research Institute.University of Wyoming.Laramie,Wyoming. Sano,S.1966.Salmon of the North Pacific Ocean -Part III.A review of the life history of North Pacific salmon.3.Chum salmon in the Far East.International North Pacific Fisheries Commission Bull.No.18.pp.41-57.Vancouver,V.C.,Cananda. Schmidt,D.C.,S.S.Hale,and D.L.Crawford (eds.).1984.Resident and Juvenile Anadromous Fish Investigations (May =October 1983). Alaska Department of Fish and Game.Su Hydro Aquatic Studies Report Series No.2.Alaska Department of Fish and Game. Anchorage,Alaska. Snedecor,G.W.and W.G.Cochran.1980.Statistical Methods.Seventh Edition.The Iowa State University Press.Ames,Iowa. SPSS,Inc.1984.SPSS/PC:SPSS for the IBM PC/XT.SPSS Incorporated, Chicago,Illinois,USA. Tautz,A.F.and G.Groot.1975.Spawning behavior of chum salmon (Oncorhynchus ketal and rainbow trout (Salmo gairdneri).J.Fish. Res.Board Can~:633-642. Trihey,E.W.1979.The IFG incremental methodology.In G.l.Smith, ed.Proceedings of the Instream Flow Criteria and Modeling Workshop.Colorado Water Resources Research Institute,Colorado State University.Pages 24-44.Information Series No.40.Fort Collins,Colorado. . •1980.Field data reduction and coding procedures for use the ----IFG-2 and IFG-4 hydraulic simulation models.Instream Flow Service Group,USFWS.Fort Collins,Colorado. - - - ""'" •and D.L.Wegner. -wi th the physi ca 1 Group.Instream Colorado. 1981.Field data collection procedures for use habi tat s;mlll ati on system of the Instream Flow Flow Service Group.lJSFWS.Fort Collins, U.S.Fish and Wildlife Service (USFWS).Unpublished draft:Habitat Suitability index models:Sockeye Salmon.USFWS.Anchorage, Al a_ska. 1/oos,K.A.1981.Simulated use of the exponential polynomial/maximum likelihood technique in developing suitability of use functions for di~R.habitat.Ph O.dissertation.Utah State University.Logan, 7-10-4 LITERATURE CITED (continued) Wesche,T.A.and P.A.Rechard.1980.A summary of instream flow methods for fisheries and related research needs.Eisenhower Consortium Bulletin.No.9.Water Resources Research Institute. University of Wyoming.Laramie,Wyoming. Withler,F.C.1982.Transplanting Pacific salmon.Can.Tech.Rep.Fish Aquati c Sci.1079.Department of Fi sheri es and Oceans.Nai namo, B.C.Cananda. Wilson,W.J.,E.W.Trihey,J.E.Baldridge,C.D.Evans,J.G.Thiele and D.E.Trudgen.1981.An assessment of envi ronmenta 1 effects of construction and operation of the proposed Terror lake hydroelectric facility,Kodiak,Alaska.Instream Flow Studies final report.Arctic Environmental Information and Data Center.University of Alaska. Anchorage,Alaska. 7-10-5 r r \ i r, i r I. 11.0 APPENDICES Appendix 7-A Calibration Data for Hydraulic Simlation Models 7-A-l Appendix Table 7-A-l.Comparison between observed and predicted water surface elevations,discharges,and velocities for 1983 Slough 8A low flow hydraulic model. - -'@.' Streambed Water Surface Station Elevation Discharge Velocity Observed Predicted Observed Predicted Adjustment -(ft)(ft)(ft)(cfs)(cfs)Factor 28+14 565.47 565.48 4 4 1.00 ~i; 29+25 565.48 565.49 4 4 0.95 30+15 565.52 565.53 4 4 0.99 31+47 565.84 565.,85 4 4 1.00 32+36 566.01 566.01 4 4 0.96 33+02 566.06 566.06 4 4 1.00 33+43 566.31 566.31 4 4 1.01 34+46 566.62 566.62 3 4 1.00 ""'" 36+22 567.20 567.20 4 4 1.00 .37+35 567.20 567.20 4 4 1.00 38+23 567.21 567.20 3 4 1.00 -Qo =4 Qp =4 28+14 565.59 565.57 8 7 1.01 29+25 565.59 565.58 7 7 0.99 30+15 565.64 565.62 8 7 0.99 31+47 566.01 565.99 7 7 1.00 32+36 566.13 566.13 8 7 0.99 ~l 33+02 566.15 566.15 7 7 1.01 33+43 566.36 566.36 7 7 0.99 34+46 566.68 566.68 8 7 1.03 36+22 567.28 567.28 7 7 1.01 ~ 37+35 567.28 567.28 7 7 1.00 38+23 567.28 567.29 8 7 1.02 Qo =7 Qp =7 -, 28+14 565.75 565.76 18 19 1.00 29+25 565.75 565.76 19 20 1.00 30+15 565.80 565.81 17 18 0.99 31+47 566.25 566.26 19 19 1.00 32+36 566.36 566.36 20 21 0.99 33+02 566.36 566.36 19 20 0.99 33+43 566.49 566.49 20 21 1.00 34+46 566.79 566.79 19 20 0.98 36+22 567.44 567.44 20 20 1.00 -37+35 567.45 567.45 21 20 1.00 38+23 567.46 567.46 19 20 0.98 Qo =19 QP~ ~ Qo is the mean observed calibration discharge.-Qp is the mean predicted calibration discharge. 7-A-2 Appendix Table 7-A-2.Comparison between observed and predicted water surface elevations,discharges,and velocities for 1983 Slough 8A high flow hydraulic model. ,~, Streambed Water Surface Station Elevation Discharge Velocity Observed Predicted Observed Predicted Adjustment (ft)(ft)(ft)(cfs)(cfs)Factor 28+14 565.75 565.75 17 17 1.00 P'"29+15 565.75 565.75 19 19 1.00 30+15 565.80 565.80 16 16 1.00 31+47 566.25 566.25 19 19 1.00-,32+36 566.36 566.36 19 19 1.00 33+02 566.36 566.36 20 20 0.99 33+43 566.49 566.49 18 18 1.00 ~34+46 566.79 566.79 18 18 0.99 36+22 567.44 567.44 20 20 1.00 37+35 567.45 567.45 20 20 1.00 38+23 567.46 567.46 19 19 1.00 fIP!II!II Qo =19 Qp =19 28+14 566.76 566.76 54 54 1.00 29+15 566.76 566.76 53 53 1.00 30+15 566.78 566.78 59 59 1.00 31+47 566.84 566.84 52 52 0.99 32+36 566.85 566.85 53 53 1.00 33+02 566.86 566.86 53 53 0.96 33+43 566.88 566.88 54 54 0.98 34+46 567.10 567.10 52 52 0.97 36+22 567.70 567.70 54 54 0.99 37+35 567.76 567.76 50 50 1.00 38+23 567.77 567.77 50 50 0.95 I-"Qo =53 Qp =53 Qo is the mean observed calibration discharge. Qp is the mean predicted calibration discharge. 7-A-3 Appendix Table 7-A-3.Analysis of covariance table,testing for equivalent slopes between rating curve relationship developed from hydraulic model versus curve from R&M staff gage data,Slough 8A. a Corrected Degrees Approximate Source of Sums of of Mean Significance Variation Squares Freedom Square F of F Data Set 0.001 1 0.001 Intercept (A) Level of (.001 1 0.001 Flow (B 1) Interaction <.001 1 0.001 0.011 0.922 (B 2) Explained 0.011 3 0.004 Residual (.001 4 0.001 Total 0.011 7 a See section 3.2.4,model number one for explanation of symbols. 7-A-4 - - .... I - Appendix Table 7-A-4.Analysis of covariance table,testing for equivalent intercepts between rating curve relationship developed from hydraulic model versus curve from R&M staff gage data,Slough SA. Source of a Corrected Degrees Approximate Sums of of Mean Significance Variation Squares Freedom Square F of F Data Set 0.011 1 0.011 3587 .000 Intercept (A) Level of .001 1 .001 Flow (B 1 ) Explained 0.011 2 0.005 Res.idua 1 .001 5 .001 Total 0.011 7 a See section 3.2.4,model number two for explanation of symbols. 7-A-5 ~ Appendix Table 7-A-5.Comparison between observed and predicted water -surface elevations,discharges and velocities for 1983 Slough 9 hydraulic model.,- Streambed Water Surface Station Elevation Discharge Velocity -. Observed Predicted Observed Predicted Adjustment (ft)(ft)(ft)(cfs)(cfs)Factor 16+47 592.40 592.40 8 8 0.99 ,jIIIfJ~, 19+42 592.60 592.60 8 8 1.01 20+00 592.75 592.75 8 8 0.99 21+77 593.37 593.36 8 8 0.98 -22+93 593.46 593.46 8 8 0.99 24+80 593.46 593.46 8 8 0.99 26+48 593.50 593.50 8 8 0.99 ~~\ 28+06 593.53 593.53 8 8 0.99 Qo =8 Qp =8 16+47 593.19 593.18 89 89 1.02 19+42 593.35 593.35 86 89 1.04 20+00 593.41 593.41 88 91 1.03 21+77 593.96 594.00 89 90 1.02 22+93 594.05 594.05 86 88 1.02 24+80 594.08 594.08 90 89 1.02 26+48 594.10 594.11 90 88 1.02 28+06 594.11 594.13 88 90 1.02 - Qo =88 Qp =89 16+47 593.43 593.45 148 148 1.00 ~, 19+42 593.59 593.58 150 148 1.01 20+00 593.63 593.66 153 151 1.02 21+77 594.15 594.18 151 150 0.99 22+93 594.20 594.23 148 146 1.00 24+80 594.24 594.26 145 148 1.01 26+48 594.28 594.29 144 146 1.01 28+06 594.33 594.31 147 149 1.00 -Qo =1"48 Qp =1"48 16+47 593.74 593.73 233 232 0.96 19+42 593.82 593.83 232 230 0.97 20+00 593.96 593.93 242 238 0.99 21+77 594.42 594.36 237 237 0.96 22+93 594.43 594.40 232 229 0.98 ~, 24+80 594.47 594.45 234 230 0.99 26+48 594.49 594.47 230 229 0.98 28+06 594.49 594.49 238 232 0.98 ~ Qo =234 Qp =232" Qo is the mean observed calibration discharge.-Qp is the mean predicted calibration discharge. 7-A-6 a See section 3.2.4,model number one for explanation of symbols. 7-A-7 Appendix Table 7-A-7.Analysis of covariance table,testing for equivalent intercepts between rating curve relationship developed from hydraulic model versus curve from ADF&G staff gage data,Slough 9. Corrected Degrees Approximate Source of a Sums of of Mean Significance Variation Squares Freedom Square F of F Data Set .001 1 .001 1.051 0.332 Intercept (A) Level of 0.037 1 0.037 Flow (B 1) Explained 0.037 2 0.019 Residual 0.003 9 .001 Total 0.040 11 a See section 3.2.4,model number two for explanation of symbols. 7-A-8 Appendix Table 7-A-8.Comparison between observed and predicted water surface elevations,discharges,and velocities for 1983 Slough 21 low flow hydraulic model. 7--A-9 Appendix Table 7-A-9.Comparison between observed and predicted water surface elevations,discharges,and velocities for 1983 Slough 21 high flow hydraulic model. Streambed Water Surface Station Elevation Discharge Velocity Observed .Predicted Observed Predicted Adjustment (ft)(ft)(ft)(cfs)(cfs)Factor -4+57 744.58 744.58 10 10 1.00 ,~ -3+57 744.59 744.59 10 10 1.00 -2+16 744.60 744.59 10 10 0.99 -1+84 744.73 744.73 10 10 1.01 -0+95 744.88 744.87 9 9 1.00 ~: Qo =10 Qp =10 -4+57 745.32 745.34 76 75 1.01 ~, -3+57 745.33 745.35 74 74 1.02 -2+16 745.35 745.38 76 74 1.03 -1+84 745.38 745.41 75 74 1.00 -0+95 745.53 745.56 70 72 1.02 Qo =----r4 Qp =74 -4+57 745.79 745.77 157 159 0.99 ~, -3+57 745.80 745.78 158 158 1.00 -2+16 745.85 745.82 154 157 1.00 -1+84 745.86 745.83 155 157 0.97 --0+95 745.99 745.96 156 154 0.98 Qo =156 Qp =157 Qo is the mean observed calibration discharge. Qp is the mean predicted calibration discharge.~ 7-A-1O Appendix Table 7-A-10.Analysis of covariance table,testing for equivalent slopes between rating curve relationship developed from hydraulic model versus curve from ADF&G staff gage data,Slough 21. Source of a Variation Corrected Sums of Squares Degrees of Freedom Mean Square F Approximate Significance of F Data Set <.001 Intercept (A) 1 <.001 Level of Flow (B 1 ) Interaction (B 2 ) Explained Residual Total 0.001 <.001 0.026 0.001 0.027 1 1 3 6 9 0.001 <.001 0.009 0(.001 0.395 0.553 a See section 3.2.4,model number one for explanation of symbols. 7-A-11 Appendix Table 7-A-11.Analysis of covariance table,testing for equivalent intercepts between rating curve relationship developed from hydraulic model versus curve from ADF&G staff gage data,Slough 21. a Corrected Degrees Approximate Source of Sums of of Mean Si gnifi cance Variation Squares Freedom Square F of F Data Set .001 1 .001 0.230 0.646 Intercept (A) Level of 0.025 1 0.025 Flow (B 1) Explained 0.026 2 0.013 Residual 0.001 7 .001 Total 0.027 9 a See section 3.2.4,model number two for explanation of symbols. 7-A-12 ..... - ~, - Appendix Table 7-A-12.Comparison between observed and predicted water surface elevations,discharges,and velocities for 1983 Side Channel 10 hydraulic model. Streambed Water Surface Station Elevation Discharge Velocity Observed Predicted Observed Predicted Adjustment (ft)(ft)(ft)(cfs)(cfs)Factor 11+25 651.27 651.27 8 8 0.87 13+65 652.16 652.16 8 8 0.99 18+57 653.53 653.53 8 8 1.00 20+85 654.39 654.39 8 8 1.00.-23+21 654.72 654.72 8 8 0.99 Qo =8 Qp =8 11+25 651.90 651.90 79 79 0.95 13+65 652.70 652.70 84 84 1.01 18+57 654.35 654.35 78 78 0.97 20+85 655.10 655.10 79 79 1.01 23+21 655.57 655.57 79 79 1.01 Qo =80 Qp =80 r- Qo is the mean observed calibration discharge. Qp is the mean precited calibration discharge. 7-A-13 Appendix Table 7-A-13.Analysis of covariance table,testing for equivalent slopes between rating curve relationship developed from hydraulic model versus curve from ADF&G staff gage data,Side Channel 10. a Corrected Degrees Approximate Source of Sums of of Mean Significance Variation Squares Freedom Square F of F Data Set <.001 1 <.001 Intercept (A) Level of <.001 1 <.001 Flow (B 1) Interaction <.001 1 <.001 0.755 0.449 (B 2) Explained 0.013 3 0.004 Residual <"•001 3 <.001 Total 0.013 6 a See section 3.2.4,model number one for explanation of symbols. 7-A-14 '"'" ,~ - ,- Appendix Table 7-A-14.Analysis of covariance table,testing for equivalent intercepts between rating curve relationship developed from hydraulic model versus curve from ADF&G staff gage data,Side Channel 10. a Corrected Degrees Approximate Source of Sums of of Mean Significance Variation Squares Freedom Square F of F Data Set .001 1 .001 0.095 0.774 Intercept (A) Level of 0.012 1 0.012 Flow (B 1) Explained 0.013 2 0.007 Residual .001 4 .001 Total 0.013 6 a See section 3.2.4,model number two for explanation of symbols. 7-A-15 Appendix Table 7-A-15.Comparison between observed and predicted water surface elevations,discharges,and velocities for 1983 Upper Side Channel 11 hydraulic model. - -Streambed Water Surface Station Elevation Discharge Velocity Observed Predicted Observed Predicted Adjustment fI1I'JJ!'A (ft )(ft)(ft)(cfs)(cfs)Factor 0+00 677 .38 677.38 13 13 0.98 2+00 677 .51 677.51 11 11 1.00 ,lJ&J\ 4+30 677.60 677.60 12 12 0.99 10+40 680.95 680.95 11 11 1.00 00 =---rz Qp =12 0+00 678.00 677.99 55 55 1.06 2+00 678.04 678.03 55 54 1.01 4+30 678.11 678.10 55 55 1.02 -10+40 681.35 681.34 53 52 1.01 Qo =55 Qp =54 ~ 0+00 678.35 678.36 106 107 0.96 2+00 678.35 678.36 113 114 1.00 4+30 678.44 678.45 112 112 0.98 IlPfti 10+40.681.63 681.64 107 108 0.99 Qo =110 Qp =110 - Qo is the mean observed calibration discharge. Qp is the mean predicted calibration discharge...,.. 7-A-16 Appendix Table 7-A-16.Analysis of covariance table,testing for equivalent slopes between rating curve relationship developed from hydraulic model versus curve from ADF&G staff gage data,Upper Side Channel 11. Source of a Variation Corrected Sums of Squares Degrees of Freedom Mean Square F Approximate Significance of F Data Set <.001 Intercept (A) 1 <.001 Level of Flow (B 1) Interaction (B 2 ) Explained Residual Total <.001 <.001 0.005 <.001 0.005 1 1 3 5 8 <.001 <.001 0.002 <.001 1.299 0.306 a See section 3.2.4,model number one for explanation of symbols. 7-A-17 Appendix Table 7-A-17.Analysis of covariance table,testing for equivalent intercepts between rating curve relationship developed from hydraulic model versus curve from ADF&G staff gage data,Upper Side Channel 11. Source of a Corrected Degrees Approximate Sums of of Mean Significance Variation Squares Freedom Square F of F Data Set .001 1 .001 0.152 0.710 Intercept (A) Level of 0.004 1 0.004 F1 ow (B 1) Explained 0.005 2 0.002 Residual .001 6 .001 Tota 1 0.005 8 a See section 3.2.4,model number two for explanation of symbols. 7-A-18 - ~, - Appendix Table 7-A-18.Comparison between observed and predicted water surface elevations,discharges,and velocities for 1983 Side Channel 21 low flow hydraulic model. Streambed Water Surface Station Elevation Discharge Velocity Observed Predicted Observed Predicted Adjustment (ft)eft)(ft)(cfs)(cfs)Factor -38+92 733.28 733.28 22 22 0.99 I"""-37+07 733.81 733.81 23 23 0.99 I -35+74 735.68 735.68 25 25 0.96 -33+42 736.09 736.09 23 23 0.90 -30+06 737.08 737.08 24 24 1.00 Qo =23 Qp =23 -38+92 733.64 733.64 100 100 0.99 -37+07 734.12 734.12 99 99 1.01 -35+74 735.90 735.90 100 100 1.00 -33+42 736.28 736.28 100 100 1.00 -30+06 737.61 737.61 100 100 1.00 Qo =100 Qp =100 Qo is the mean observed calibration discharge. Qp is the mean predicted calibration discharge. 7-A-19 Appendix Table 7-A-19.Comparison between observed and predicted water surface elevations,discharges,and velocities for 1983 Side Channel 21 high flow hydraulic model. - Streambed Water Surface Station Elevation Discharge Velocity Observed Predicted Observed Predicted Adjustment (ft)(ft)(ft)(cfs)(cfs)Factor -38+92 733.64 733.64 100 100 0.98 "'"' -37+07 734.12 734.12 99 100 0.99 -35+74 735.90 735.90 100 100 1.00 -33+42 736.28 736.28 100 100 1.00 JlID~, -30+06 737.61 737.61 100 100 1.00 Qo =100 Qp =100 ~ -38+92 734.99 735.01 431 431 1.05 -37+07 735.18 735.18 433 433 1.01 -35+74 736.55 736.57 430 430 1.00 -33+42 737.06 737.07 4,31 430 1.00 -30+06 738.29 738.28 430 430 1.02 Qo =431 Qp =431 --38+92 735.98 735.96 775 775 0.98 -37+07 736.02 736.02 783 783 0.99 -35+74 736.97 736.95 775 777 1.00 ~-33+42 737.54 737.53 773 774 1.OC -30+06 738.63 738.63 773 773 1.00 Qo =776 Qp =776 ~ Qo is the mean observed calibration discharge. ~, Qp is the mean predicted calibration discharge. 7-A-20 ~' Appendix Table 7-A-20.Analysis of covariance table,testing for equivalent slopes between rating curve relationship developed from hydraulic model versus curve from AOF&G staff gage data,Upper Side Channel 21. Corrected Degrees Approximate Source of a Sums of of Mean Significance Variation Squares Freedom Square F of F Data Set <.001 1 <.001 Intercept (A) Level of 0.001 1 0.001 Flow (B 1) Interaction <.001 1 <.001 3.560 0.101 (B 2 ) Explained 0.014 3 0.005 Residual <.001 7 <.001 Total 0.014 10 a See section 3.2.4,model number one for explanation of symbols. 7-A-21 Appendix Table 7-A-21.Analysis of covariance table,testing for equivalent intercepts between rating curve relationship developed from hydraulic model versus curve from ADF&G staff gage data,Upper Side Channel 21. a Corrected Degrees Approximate Source of Sums of of Mean Significance Variation Squares Freedom Square F of F Data Set .001 1 .001 0.948 0.258 Intercept (A) Level of 0.014 1 0.014 Flow (8 1) Explained 0.014 2 0.007 Residual 0.001 8 .001 Total 0.014 10 a See section 3.2.4,model number two for explanation of symbols'. 7-A-22 ""'" ~, - ~'l -]]] SLOUGH SA La -HYDRAULIC MODEL 1 I 1 1 6 I n=1I15 I r =0.99 5 n. +'--4v l: l- IIW ........0 I :3 ::D-o I W N I- W 0 0 Iii 2n: 1L 0- o x 2 4 OBSERVED DEPTH (tt) 2 1.9 1.8 1.7 1.6 '"1.5•';>1.4 0 1.3 ~1.2U1.191w>0.9~0.8 0.7a0.6It:0.5n. 0.4 0.3 0.2 0.1 0 06 n=1I15 r =0.99 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 OBSERVED VELOCITY Ut/s) Appendix Figure 7-A-l.Scatter plots of Slough 8A low flow observed and predicted depths and velocities.The diagonal line in each plot represents the theoretical one-to-one relationship (i.e.observed=depth);the lines bounding the one to-one line represents cutoff limits as defined in the methods section. SLOUGH SA HI -HYDRAULIC MODEL 2 1.9 i 0=811l.B r =0.97 1.7 1.6 '"'1.5rJ ""1.4....'+-v 1.3 ~1.2 U 1.10 -l 0;Iw xX x> 0w O.B x f-Xu0.7Ci Xw0.6 lr Xa.0.5 0.4 0.3 0.2 0.1 0 6 0 0.2 0.4 0.6 O.B 1 1.2 1.4 1.6 l.B 2 OBSERVED VELOCITY (1l/5) 42 X OBSERVED DEPTH (Il) o ~..I I I I I I o 6 I 0=811 r =0.99 5 '"'<, '+-4v I f-a. W 0 -....J 3 I 0 :l::>W I f- N U +:>0w 2lra. Appendix Figure 7-A-2.Scatter plots of Slough 8A high flow observed and predicted depths and velocities.The diagonal line in each plot represents the theoretical one-to-one relationship (i.e.observed=depth);the lines bounding the one-to-one line represent cutoff limits as defined in the methods section. I .~J )I )1 )I •i 1 1 I j , ]1 --~l J ]]I 1 1 j SLOUGH 9 -HYDRAULIC MODEL , ~' 5 1 7/1 3 n =1485 2.81 n =1485 r =0.99 r =0.98 2.6 4i 2.4 r. 2.211 r."'-..............2\J 'V I :5 ~1.8l-n.Uw0 1.6-.....J a ..J I W ~a >1.4 I w N I-a U1 0 2 w 1.2~f- U 0:6n.w 0::0.8r!lx 0.6 x.. x 0.4 0.2 o ,....I 0IIII 0 2 4 0 0.4 0.8 1.2 1.6 2 2.4 2.8 OBSERVED DEPTI-I (ft)OBSERVED VELOCITY (ftjs) Appendix Figure 7-A-3.Scatter plots of Slough 9 low observed and predicted depths and velocities. The diagonal line in each plot represents the theoretical one-to-one relationship (i.e.observed=depth);the lines bounding the one-to-one line represents cutoff limits as defined in the methods section. SLOUGH 21 LO HYDRAUUC MODEL 3 1.5 2.8 n =251 1. 4 1 n =251 2.6 r =0.97 1.3 r =0.99 2.4 1.2 2.2 "1.1II ""-+'+'...2 ... 'J 'J I 1.8 ~0.9f-a.uw1.6 0 0.8"'-.J 0 .J I 0 W ):;,1.4 >0.7 I w N f-0 (J')U 1.2 w 0.60f- W 1 u It:0 0.5 a.w 0.8 It:0.4II 0.6 XX 0.3 0.4 0.2 0.2 0.1 0 0 0 0.4 O.B 1.2 1.6 2 2.4 2.8 0 0.2 0.4 0.6 0.8 1 1.2 1.4 OBSERVED DEPTH (It)OBSERVED VELOCITY (Il/s) Appendix Figure 7-A-4.Scatter plots of Slough 21 low flow observed and predicted depths and velocities. The diagonal line in each plot represents the theoretical one-to-one relationship (i.e.observed=depth);the lines bounding the one-to-one line represent cutoff limits as defined in the methods section. J I 1 I 1 J 1 ~.~I )J J 1 I I J J "I ~~-J '1 1 J -j --n -)J ) 2.82.41.2 1.6 2 OBSERVED VELOCITY (lt/s) SLOUGH 21 HI HYDRAULIC MODEL 3 2.8 i n=484 2.6 r =0.98 2.4 ,.... II 2.2"... "<-2'oJ (:1.8 U 0 1.6.Jw>1.4 0w 1.2I-u 0w I XII':0.81L 0.6 0.4 0.2 0 2 3 4 0 0.4 0.8 OBSERVED DEPTH (It) o~"I I I I I I I o 0.5 4 35 1 n=484 r =0.98 3 ,....... "<- 'oJ I 2.5 l- II W .........0 I 2 );:>0 WIl-N U......... 0 1.5w II': 1L Appendix Figure 7-A-5.Scatter plots of Slough 21 high flow observed and predicted depths and velocities. The diagonal line in each plot represents the theoretical one-to-one relationship (i .e.observed=depth);the lines bounding the one-to-one line represents cutoff limits as defined in tile methods section. SIDE CHANNEL 10 HYDRAULIC MODEL 43 x x 2 OBSERVED VELOCITY (lt/s) x n=343 r =0.98 '2 ,'7 ...4 1.9 1.B 1 n =343 r =0.98 /F I 3,5 1.7 1.6 1.5 x r-3il r-1.4 "-............... '--'1.3 '--' I 1.2 ~2.5 l- II 1.1 u'-.J W 0I0--l :D 1 w 2 I 0 >N w 0.9 x 00 I-0uO.B w 0 I-1.5 w 0.7 0 rr 0 Il 0.6 wrr 0.5 Il Il 0.4 0.3 ,I "'f,Jl1>U.0.5 0.2 0.1 O~-'I I aIIIIIIIII I I I I I I I I a 0.2 0.4 0.6 O.B 1 1.2 1.4 1.6 I.B 2 a OBSERVED DEPTH (It) Appendix Figure 7-A-6.Scatter plots of Side Channel 10 observed and predicted depths and velocities. The diagonal line in each plot represents the theoretical one-to-one relationship (i .e.observed=depth);the lines bounding the one-to-one line represent cutoff limits as defined in the methods section. J I I ,I J I I .J 1 I J )I ) ••I ,J 1 1 1 --1 ~l ---1 I 1 2.82.41.2 1.6 2 OBSERVED VELOCITY (tt/s) SIDE CHANNEL 11 UPPER HYDRAULIC MODEL 3 2.81 n =411 r =0.992.6 2.4 ,.... 2.2n "-.... 0 2 ~1.8 u 0 1.6.Jw>1.4 0w 1.2f-u 0 W 0::0.8n. 0.6 0.4 0.2 0 2 3 4 0 0.4 0.8 OBSERVED DEPTH (ft) o j-, I I J I I I I o 0.5 4 I n =411 3.5...j r =0.99 3 ,............. '-' I 2.5 f-n.w D "'-J 2 I 0 )::>W I f- N U l.D 0 1.5w 0::n. Appendix Figure 7-A-7.Scatter plots of Upper Side Channel 11 observed and predicted depths and velocities. The diagonal line in each plot represents the theoretical one-to-one relationship (i .e.observed=depth);the lines bounding the one-to-one line represent cutoff limits as defined in the methods section. SIDE CHANNEL 21 LO HYDRAULIC MODEL 1.5 1. 4 1 n =171 r =0.941..3 1.2 r, ~1.1',,- +' 0 ~0.9 0 0 0.8-lw>0.7 0w 0.6f- 0 Ci 0.5 wa::0.4[l 0..3 0.2 0.1 0 4 0 0.2 0.4 0.6 0.8 1 1.2 1.4 OBSERVED VELOCITY (ft/s) .32 OBSERVED DEPTH (ft) o P'q I I I I I I I I o 0.5 4 I n =171 .3.5 -1 r =0.94 .3 r, +'.......... I 2.5 f- [L W --.,J 0 I 2 :t;>0 I W W f- a 0 0 1.5wa::n. Appendix Table 7-A-8.Scatter plots of Side Channel 21 low flow observed and predicted depths anJ velocities.The diagonal line in each plot represents .the theoretical one- to-one relationship (1.e.observed=depth);the lines bounding the one-to-one line represents cutoff limlts as defined in the methods section. t J I J J I I ),J I i J J J )~I ]II ]l 'J J 1 ]1 1 42 OBSERVED VELOCITY (ft/s) o~I I I I I o64 OBSERVED DEPTH (fl) 2 o ~---I ,--,---,I I I o SIDE CHANNEL 21 HI HYDRAULIC MODEL 7 1----------------77 5 I n =704n=704 r =0.99 6 1 r =0.99 4 "II "5 ""-...;::0'---' I ~3I-U0-4w 0 '-l 0 ..J WI0>:P WII-3 0w0w 2.....0 I- 0W 0It: 0-W2It:n. Appendix Figure 7-A-9.Scatter plots of Side Channel 21 high flow observed and predicted depths and velocities.The diagonal line in each plot represents the theoretical one- to-one relationship (i.e.observed=depth);the lines bounding the one-to-one line represent cutoff limits as defined in the ~ethods section. .... APPENDIX 7B Salmon Spawning Utilization Data 7-B-1 •,~.._~..L_....."....r·~~·v'~~~<"'. Table 7-8-1 Habitat data collected at chum salmon redds. --------------------------------------------------------------------------------------------------------------------------------- WATER VELO-.SUBSTRATE WATER TEMPERATURE (C)DI STANCE DEPTH .CITY ----------------------------------------------REDD (FT)TO LOCATION DATE (FT)(FT/S)PRlHARY SECONDARY INTRAGRAVEL SURFACE NO.UPWELLING UPWELLING --------------------------------------------------------------------------------------------------------------------------------- SLOUGH 9 830906 .90 .30 COBBLE LARGE GRAVEL S.6 6.3 1 PRESENT 6 SLOUGH 9 830906 1.30 .02 .RUBBLE LARGE GRAVEL S.2 6.3 2 PRESENT 3 SLOUGH 9 830906 1.00 .2S COBBLE LARGE GRAVEL 4.7 6.2 3 PRESENT 10 SLOUGH 9 830906 1.30 .35 RUBBLE LARGE GRAVEL 4,3 6.6 4 PRESENT 3 SLOUGH 9 830906 1.10 .10 COBBLE SAND 4.6 6.5 5 PRESENT 3 '-J SLOUGH 9 830906 1.00 .3 S SAND LARGE GRAVEL 4.3 6.7 6 UNKNOWN I SLOUGH 9 830906 1.20 .35 SHALL GRAVEL RUBBLE 4.3 6.8 7 UNKNOWNOJ I SLOUGH 9 830906 1.10 .30 LARGE GRAVEL RUBBLE 4.1 6.8 8 UNKNOWNNSLOUGH9830906.70 .OS LARGE GRAVEL SHALL GRAVEL 4.1 5.9 9 PRESENT 4 SLOUGH 9 830906 .6S .80 RUBBLE SHALL GRAVEL 4.0 7.4 10 UNKNOWN SLOUGH 9 830906 .70 .SO RUBBLE SMALL GRAVEL 4.1 7.4 11 UNKNOWN SLOUGH 9 830906 .60 .70 RUBBLE SMALL GRAVEL 4.2 7.4 12 UNKNOWN SLOUGH 9 830906 .75 1.1 ~RUBBLE SHALL GRAVEL 4.0 7.5 13 UNKNOWN SLOUGH 9 830906 .90 1.10 COBBLE SHALL GRAVEL 3.9 7.5 14 UNKNOWN SLOUGH 9 830906 .60 1.20 LARGE GRAVEL SHALL GRAVEL 4.1 7.6 15 UNKNOWN SLOUGH 9 830906 1.00 .5S RUBBLE SMALL GRAVEL 4.0 7.8 16 UIfl(NOWN SLOUGH 9 830906 .80 .60 SAND RUBBLE 4.0 7.9 17 UIfl(NOWN SLOUGH 9 830906 .50 .55 SHALL GRAVEL RUBBLE 4.6 7.9 18 UNKNOWN SLOUGH 9 830906 .50 .45 COBBLE SHALL GRAVEL 3.6 7.6 19 UNKNOWN SLOUGH 9 830906 .90 .45 COBBLE SHALL GRAVEL 3.9 7.7 20 UNKNOWN SLOUGH 9 830906 1.00 .45 RUBBLE SHALL GRAVEL 3.9 8.0 21 UNKNOWN SLOUGH 9 830906 .60 .10 SAND RUBBLE 4.4 8.2 22 UNKNOWN SLOUGH 9 830906 .75 0.00 RUBBLE SHALL GRAVEL 4.8 8.8 23 UNKNOWN SLOUGH 9 830906 .60 0.00 LARGE GRAVEL SHALL GRAVEL 4.7 8.8 24 UNKNOWN SLOUGH 9 830906 1.00 .25 RUBBLE LARGE GRAVEL 6.2 7.1 25 Ut:KNOWN SLOUGH 9 830906 1.50 .20 LARGE GRAVEL RUBBLE 5.9 7.1 26 UNKNOWN --------------------------------------------------------------------------------------------------------------------------------- I J I J J J J ~J !]J J ~J J 1 J J »1 1 J J 1 )1 J }1 .__..._~..,_-._~_._"._...._._--~-,. Table 7-&-1 Continued --------------------------------------------------------------------------------------------------------------------------------- WATER VELO-SUBSTRATE WATER TEMPERATURE (C)DISTANCE DEPTH CITY . ----------------------REDD (fT)TO------------------------ LOCATION DATE (FT)(fT/S)PRIMARY SECoNDARY INTRAGRAVEL SURFACE NO.UPWELLING UPI.IELLING ---------------------~----------------------------------------------------------------------------------~------------------~----- SLOUGH 9 830906 .40 0.00 SMALL GRAVEL RUBBLE 5.7 6.9 27 UNKNOWN SLOUGH 9 830906 .70 .70 SMALL GRAVEL RUBBLE 5.2 7.3 28 UNKNOWN SLOUGH 9 830906 .60 .40 LARGE GRAVEL SMALL GRAVEL 5.5 7.3 29 UNKNOWN SLOUGH 9 830906 .55 .55 RUBBLE SHALL GRA vn 6.9 8.8 30 UNKNOWN SLOUGH 9 .830906 .60 .15 LARGE GRAVEL SHALl.GRAVEL 5.6 7.3 31 UNKNOWN -.....J SLOUCH 8A 830815 lo60 .23 RUBBLE LARGE GRAVEL 6.0 9.2 1 I SLOUGH SA 830815 1.30 .25 RUBBLE LARGE GRAVEL 6.2 9.3 2OJ I SLOUGH SA 830815 1.40 .25 RUBBLE LARGE GRAVEL 5.2 9.1 3wSLOUGH8A8308151.40 .30 RUBBLE LARGE GRAVEL 5.0 9.6 4 SLOUGH 8A 830815 1.30 .50 RUBBLE LARGE GRAVEL 5.6 9.1 5 SLOUGH 8A 830S15 1.00 .45 RUBBLE LARGE GRAVEL 6.4 9.1 6 SLOUGH SA S30815 1.10 .65 RUBBLE SMALL GRAVEL 5.4 9.1 7 SLOUGH SA 830816 lo55 0.00 RUBBLE LARGE CRAVEL 5.3 10.0 8 UNKNOWN SLOUGH SA 830816 1.50 .08 SMALL GRAVEL RUBBLE 5.8 10.3 9 UNKNOWN SLOUGH SA S30902 .90 .05 LARGE GRAVEL RUBBLE 4.7 9.7 10 UNKNOWN SLOUGH SA S30902 .90 0.00 LARGE GRAVEL RUBBLE 4.9 9.8 11 UNKNOWN SLOUGH SA 830902 1.00 0.00 LARGE GRAVEL RUBBLE 5.8 9.4 12 UNKNOWN SLOUGH SA 830902 1.20 .05 RUBBLE SHALL GRA VI::L 5.9 10.2 13 UNKNOWN SLOUGH SA 830902 1.00 .20 RUBBLE LARGE GRAVEL 7.2 10.3 14 UNKNOWN SLOUGH SA 830902 2.80 0.00 LARGE GRAVEL SMALL GRAVEL 10.2 15 UNKNOWN 4TH OF JULY CREEK MOUTH 830817 1.00 .60 LARGE GRAVEL RUBBLE 10.6 11.6 1 UNKNOWN 4TH OF JULY CREEK MOUTH 830817 lo70 .75 COBBLE RUBBLE 11 .5 11.6 2 UNKNOWN --------------------------------------------------------------------------------------------~------------------------------------ ."-,,",~->,,~-,,,~.,....,~.-'.~ Table 7-&-1 Continued ------------------------------~----------------------------~--------------~------------------------------------------------------WATER VELO-.SUBSTRATE ~ATER TEMPERATURE (c)DISTANCE DEPTH CITY -----------------------~----------------------REDO (FT)TO LOCATION DATE (rr)(FT/S)PRIMARY SECONDARY INTRAGRAVEL SURFACE NO.UPWELLING UP\.IELLING -------------------------------------------------------------------------------------------------------------~----------------~-- 4TH OF JULY CREEK HOUTH 830817 1.60 .10 LARGE GRAVEL RUBBLE 11.2 11.6 3 UNKNOWN 4TH OF JULY CREEK HOUTH 830811 2.20 .60 LARGE GRAVEL RUBBLE 10.2 11.6 4 4TH OF JULY CREEK HOUTH 830817 2.00 .60 LARGE GRAVEL RUBBLE 10.8 11.1 5 4TH OF JULY CREEK HOUTH 830811 2.30 .60 LARGE GRAVEL RUBBLE 10.1 11.6 6 4TH OF JULY CREEK HOUTH 830811 2.10 .10 COBBLE RUB BLE 11.0 11.9 1 4TH OF JULY CREEK HOUTH 830811 1.00 .25 SMALL GRAVEL LARGE GRAVEL 11.3 11.9 8.......4TH OF JULY CREEK HOUTH 830811 1.00 .25 RUB BLE LARGE GRAVEL 11.3 11.9 9I OJ 4TH OF JULY CREEK HOUTH 830811 1.10 .20 RUBBLE LARGE GRAVEL 11.2 11 .8 10I +:> 4TH OF JULY CREEK HOUTH 830818 2.10 1.35 RUBBLE COBBLE 11 .8 12.2 12 UNKNOWN 4TH OF JULY CREEK HOUTH 830818 1.50 .10 SMALL GRAVEL SAND 10.4 12.0 13 UNKNOWN 4TH OF JULY CREEK MOUTH 830818 1.10 2.10 LARGE GRAVEL SMALL GRAVEL 1 .5 12.3 14 UNKNOWN 4TH OF JULY CREEK MOUTH 830818 1.90 4.50 RUBBLE COBBLE 8.1 12.3 15 UNKNOWN 4TH OF JULY CREEK HOUTH 830822 2.20 1.30 RUBBLE LARGE GRAVEL 9.1 11.2 16 4TH OF JULY CREEK MOUTH 830822 2.00 1.00 RUBBLE LARGE GRAVEL 11.1 11.3 11 4TH OF JULY CREEK HOUTH 830822 1.80 1.40 RUBBLE SAND 11.0 11.3 18 4TH OF JULY CREEK HOUTH 830822 2.00 1.80 RUBBLE LARGE GRAVEL 9.3 11.3 19 4TH OF JULY CREEK HOUTH 830822 1.30 2.20 RUBBLE LARGE GRAVEl.9.8 11.2 20 4TH OF JULY CREEK HOUTH 830822 .90 2.00 RUBBLE LARGE GRAVEL 11.4 11.3 21 UNKNOWN 4TH OF JULY CREEK MOUTH 830822 1.20 3.10 RUBBLE .LARGE GRAVEL 11.3 11.3 22 UNKNOWN 4TH OF JULY CREEK HOUTH 830822 1.10 2.00 RUBBLE COBBLE 11.4 11.3 23 UNKNOWN 4TH OF JULY CREEK HOUTH 830828 .10 .40 9.5 10.T 24 4TH OF JULY CREEK HOUTH 830828 1.10 2.50 9.4 10.1 25 4TH OF JULY CREEK HOUTH 830828 .90 .80 9.0 10.6 26 .1 I J !I 3 .~,J j .1 I J J )1 I ,]J J 1 1 i 1 1 1 }1 -«-~------~----_._--_._.".....__.__. Table 7-B-1 Continued ---------------------------~--------------------------------------------------------~--------------------------------------------WATER VELO-SUBSTRATE WATER TEMPERATURE (c)DISTANCE DEPTH CITY ----------------------------------------------REDO (FT)TO LOCATION DATE (rt)(FT/s)PRIMARY SECONDARY INTRAGRAVEL SURFACE NO.UPWELLING UPWELLING -----------------------------------------------------------------------------------------------------------------------_.-------- 4TH OF JULY CREEK HOUTH 830828 .70 .75 8.7 10.6 27 4TH or JULY CREEK HOUTH 830828 .60 1.20 10.1 10.7 28 4TH OF JULY CREEK HOUTH 830828 1.10 .10 5.7 10.8 29 SIDE CHANNEL 250 FT 830823 1.60 2.40 LARGE GRAVEL RUBBLE 8.8 1 UNIWOWN ABOVE 4TH OF JULY "-J SLOUGH 9A 830910 .93 .60 RUBBLE LARGE GRAVEL 6.7 6.0 1 PRESENT 20I 03 SLOUGH 9A 830910 1.12 0.00 RUBBLE LARGE GRAVEL 6.3 6.1 2 UNKNOWNISLOUGH9A8309101.30 .40 LARGE GRAVEL 6.4 6.0 3 PRESENT 15(Yl RUBBLE SLOUGH 9A 830910 .90 .62 LARGE GRAVEL RUBBLE 6.2 6.3 4 UNKNOWN SLOUGH 9A 830910 .60 1.80 LARGE GRAVEL RUBBLE 5.8 6.0 5 UNKNOWN SLOUGH 9A 830910 1.45 0.00 COBBLE LARGE GRAVEL 5.1 6.7 6 PRESENT 30 SLOUGH 9A 830910 1.63 .62 RUBBLE LARGE GRAVEL 5.1 6.7 7 PRESENT 10 SLOUGH 9A 830910 1.20 .28 RUBBLE LARGE GRAVEL 4.3 8.2 8 UNKNOWN SLOUGH 9A 830910 1.30 .10 RUBBLE LARGE GRAVEL 4.6 7.5 9 UNKNOWN SLOUGH 9A 830910 1.38 0.00 LARGE GRAVEL SMALL GRAVEL 4.4 7.0 10 UNKNOWN SLOUGH 9A 830910 1.41 0.00 LARGE GRAVEL SHALL GRAVEL 4.7 7.1 11 UNKNOWN SLOUGH 9A 830910 1.31 0.00 LARGE GRAVEL SMALL GRAVEL 4.6 6.9 12 UNKNOWN SLOUGH 9A 830910 1.10 0.00 LARGE GRAVEL RUBBLE 4.7 6.9 13 UNKNOWN SLOUGH 9A 830910 1.00 0.00 RUBBLE COBBLE 4.7 6.9 14 UNKNOWN SLOUGH 9A 830910 .90 .50 RUBBLE LARGE GRAVEL 4.4 8.4 15 UNKNOWN SLOUGH 9.~830910 1.40 .10 RUBBLE LARGE GRAVEL 5.8 8.5 16 UNKNOWN SLOUGH 9A 830910 1.54 .10 COBBLE RUBBLE 8.2 8.7 17 UNKNOWN SLOUGH 9A 830910 1.10 .20 RUBBLE LARGE GRAVEL 4.8 8.6 18 UNKNOWN SLOUGH 9A 830910 1.10 .10 RUBBLE LARGE GRAVEL 4.0 8.5 19 UNKNOWN SLOUGH 9A 830910 1.30 .15 RUBBLE COBBLE 5.3 8.5 20 UNKNOWN --------------------------------------------------------------------------------------------------------------------------------- ....."..__~..-'.._.._.,______~__•._"_.__•.~____.___._._~_'_._.____.~_,__~.._,~n_.··___'.____,....._........_.~._.___..___.._.'__.".__....."_..__......_-----,..._."- Table 7-fl-l Continued -------------------------------------------------------------------------------------------------------------------------------- WATER VELO-SUBSTRATE WATER TDIPERATURE (C)DISTANCE DEPTH CITY ----------------------------------------------REDO (FT)TO LOCATION DATE (FT)(FT/S)PRI"HARY SECONDARY I NTRAGRA VEL SURFACE NO.UPWELLING UPWELLING -------------------------------------------~--------------------------------------------------------.._-------------------------- SLOUGH 9A 830910 1.48 .08 RUBBLE COBBLE 4.1 8.5 21 UNKNOWN SLOUGH 9A 830910 1.80 .15 COBBLE BOULDER 1.3 8.1 22 UNKNOWN SLOUGH 9A 830910 1.00 0.00 RUBBLE LARGE GRAVEL 4.8 8.1 23 PRESENT 10 SLOUGH 9A 830910 .90 0.00 RUBBLE LARGE GRAVEL 3.9 8.5 24 PRESENT 10 SLOUGH 11 830811 1.60 .18 SMALL GRAVEL RUBBLE 6.2 7.2 21 '-J SLOUGH 11 830816 1.95 .20 RUBBLE LARGE GRAVEL 4.4 9.2 8 UNKNOWNIcoSLOUGH118308162.10 .20 RUBBLE SMALl.GRAVEL 7.2 9.1 9 UNKNOWN I SLOUGH 11 830816 1.20 .20 LARGE GRAVEL SMALL GRAVEL 4.6 8.9 10 UNKNOWNCJ"l SLOUGH 11 830816 1.20 .20 LARGE GRAVEL SMALL GRAVI::L 5.4 8.9 11 UNKNOWN SLOUGH 11 830816 .65 .10 LARGE GRAVEL SMALL GRAVEl.5.4 8.3 12 UNKNOWN SLOUGH 11 830820 .45 .20 LARGE GRAVEL SMALL GRAVEL 3.7 5.3 1 UNKNOWN SLOUGH 11 830820 .60 .40 LARGE GRAVEL RUBBLE 4.3 5.6 2 UNKNOWN SLOUGH 11 830820 .60 1.40 LARGE GRAVEL RUBBLE 5.0 5.6 3 UNKNOWN SLOUGH 11 830820 .50 .20 LARGE GRAVEL RUBBLE 3.8 5.4 4 UNKNOWN SLOUGH 11 830820 .70 .05 LARGE GRAVEL RUBBLE 3.8 4.8 5 UNKNOWN SLOUGH 11 830820 2.20 0.00 LARGE GRAVEL RUBBLE 3.2 5.9 6 UNKNOWN SLOUGH 11 830820 2.10 0.00 LARGE GRAVEL RUBBLE 3.1 5.9 7 UNKNOWN SLOUGH 11 830820 2.10 0.00 LARGE GRAVEL RUBBLE 3.2 5.9 13 UNKNOWN SLOUGH 11 830820 1.70 0.00 LARGE GRAVEL RUBBLE 3.2 5.8 14 UNKNOWN SLOUGH 11 830820 1.40 .18 LARGE GRAVEL RUBBLE 3.5 5.1 15 UNKNOWN SLOUGH 11 830820 .80 0.00 LARGE GRAVEL RUBBLE 3.2 5.0 16 UNKNOWN SLOUGH 11 830820 1.20 0.00 LARGE GRAVEL S~~LL GRAVEL 3.1 4.5 11 UNKNOWN SLOUGH 11 830820 2.10 .08 RUBBLE LARGE GRAVEL 2.9 4.6 18 UNKNOWN ------------------------------------------------------------------------------------------------------~-------------------------- 1 J I I J ,J J I !~1 i J I J I J ]1 1 1 ..~-]-1 1 1 J ]1 ..~.----"-._---_.,._-.,-.,",.--_.-._"-"----_.--_. Table 7-&-1 Continued -------------~------------------------------------------------------------------------------------------------------------------- WATER VELO-SUBSTRATE WATER TEMPERATURE (C)DISTANCE DEPTH CITY ----------------------------------------------REDD (FT)TO. LOCATION DATE (FT)(FT/S)PRlHARY SECONDARY INTRAGRAVEL SURFACE NO.UPWELLING UPWELLING ------------------------------------------------------------------------------------------------------------------------~-------- SLOUGH 11 830820 1.90 .OB SHALL GRAVEL LARGE GRAVEl.2.9 4.6 19 UNKNOWN SLOUGH 11 830820 1.90 .10 LARGE GRAVEL RUBBLE 2.9 4.7 20 UNKNOWN SLOUGH 11 830827 .95 .10 8.0 22 UNKNOWN SLOUGH 11 830827 1.00 .10 8.0 23 UNKNOWN SLOUGH 11 830827 .60 .05 8.5 24 UNKNOWN -....J SLOUGH 11 830827 1.50 .10 8.0 25 UNKNOWN I SLOUGH 11 830827 1.00 .OS 8.0 26 UNKNOWNOJ I SLOUGH 11 830827 2.00 .05 8.0 27 UNKNOWN-....J SLOUGH 11 830827 2.10 .OS 8.0 28 UNKNOWN SLOUGH 11 830827 2.60 0.00 8.0 29 UNKNOWN SLOUGH 11 830827 .60 0.00 7.0 30 UNKNOWN SLOUGH 11 830827 1.S0 0.00 8.5 31 UNKNOWN SLOUGH 11 830827 I.S0 0.00 8.0 32 UNKNOWN SLOUGH 11 830827 2.00 .OS 8.0 ))UNKNOWN SLOUGH 11 830827 1.90 0.00 8.0 34 UNKNOWN SLOUGH 11 830827 2.S0 0.00 9.S 3S UNKNOYN SLOUGH 11 830910 1.55 0.00 RUBBLE LARGE GRAVEL 3.6 7.2 36 UNKNOWN SLOUGH 11 830910 1.40 0.00 RUBBLE LARGE GRAVEL 3.7 6.6 37 UNKNOWN SLOUGH 11 830910 1.63 0.00 RUBBLE LARGE GRAVEL 3.S 6.9 38 UNKNOWN SLOUGH 11 830910 1.S0 0.00 RUBBLE COBBLE 4.0 7.0 39 UNKNOWN SLOUGH 11 830910 2.00 0.00 COBBLE BOULDER 40 UNKNOWN SLOUGH 11 830910 .70 .15 SHALL GRAVEL LARGE GRAVEL 41 UNKNOWN SLOUGH 11 830910 .96 .10 COBBLE RUBBLE 42 UNKNOYN SLOUGH 11 830910 .60 0.00 COBBLE RUBBLE 43 UNKNOWN --------------------------------------------------------------------------------------------------------------------------------- .~,_"_,__,,_,,__._•__,_~.'_"_'__.·F ..__._...•__._ Table 7 -8-1 Continued -------------------------------------------------------------------------------------------------------------------------------- WATER VELO-SUBSTRATE WATER TEMPERATURE (c)DISTANCE DEPTH CITY ----------------------------------------------REDD (rr)TO LOCATION DATE (FT)(rr/s)YRIHARY SECONDARY I NTRAGRA VEL SURFACE NO.UPWELLING UPWELLING -----------------------------------------------------------------------"-------------------~------------------------------------ SLOUGH 11 830910 1.52 0.00 RUBBLE COBBLE 44 UNKNOWN SLOUGI1 11 830910 1.10 0.00 RUBBLE COBBLE 45 UNKNOWN SLOUGH 11 830910 1.18 0.00 'RUBBLE COBBLE 46 UNKNOWN SLOUGH 11 830911 .40 .75 LARGE GRAVEL SMALL GRAVEL 47 UNKNOWN SLOUGH 11 830911 .24 .35 LARGE GRAVEL SMALL GRAVEL 48 UNKNOWN '-J SLOUGH 11 830911 .90 0.00 RUBBLE COBBLE 49 UNKNOWN I SLOUGH 11 830911 1.20 .05 LARGE GRAVEL RUBBLE 50 UNKNOWNco I SLOUGH 11 830911 1.70 0.00 RUBBLE LARGE GRAVEL 51 PRESENTcoSLOUGH118309112.90 0.00 RUBBLE LARGE GRAVEL 52 PRESENT 10 SLOUGH 11 SIDE CHANNEL (UPPER)830823 1.50 2.10 RUBBLE LARGE GRAVEL 9.1 1 UNKNOWN SLOUGH 11 SIDE CHANNEL (UPPER)830823 2.30 2.40 SAND RUBBLE 9.1 2 UNKNOWN INDIAN RIVER (HOUTH)830820 1.40 .60 RUBBLE LARGE GRAVEL 8.5 8.2 1 INDIAN RIVER (HOUTH)830820 1.20 .1.5 RUBBLE LARGE GRAVEL 8.4 8.7 2 INDIAN RIVER (HOUTH)830820 1.90 .42 RUBBLE LARGE GRAVEL 8.8 8.2 3 SLOUGH 17 830820 .70 .20 LARGE GRAVEL RUBBLE 5.0 5.4 1 PRESENT 60 SLOUGH 17 830820 .80 .40 LARGE GRAVEL RUBBLE 5.1 5.2 2 PRESENT 6.5 SLOUGH 17 830901 1.70 0.00 LARGE GRAVEL RUBBLE 4.8 .5.0 4 UNKNOWN SLOUGH 17 830901 1..50 0.00 LARGE GRAVEL SHALL GRAVEL 4.7 4.8 5 UNKNOWN SLOUGH 17 830901 1.90 0.00 RUBBLE COBBLE 4.1 4.8 6 UNKNOWN SLOUGH 17 830901 2.60 0.00 RUBBLE COBBLE 5.0 7 UNKNOWN ••J I I J I I !••J J I ]I J I I ,I ----,1 )--1 J 1 -J -~~I ---1 -1 --1 1 1 .] -,._._-_._.-~.- Table 7-8-1 Continued --------------------------------------------------------------------------------------------------------------------------------- WATER VELO-SUBSTRATE WATER TEMPERATURE (c)DISTANCE DEPTH CITY ----------------------------------------------REDO (FT)TO LOCATION DATE (FT)(FT/S)'PRIHARY SECONDARY INTRAGRAVEL SURFACE NO.UPWELLING UPWELLING -----------------------------------------------~-------------------------_._----------------------------------------------------- SLOUGH 20 830819 .60 1.00 .RUBBLE LARGE GRAVEL ~.8 9.8 1 PRESENT 10 SLOUGH 20 830819 .10 .90 RUBBLE SHALL GRAVEL ~.~10.1 2 PRESENT IS SLOUGH 20 830819 .10 1.10 LARGE GRAVEL SHALL GRAVEL 6.1 9.2 3 UNKNOWN SLOUGH 20 830819 .60 1.10 LARGE GRAVEL SHALL GRAVEL S.8 9.2 4 UNKNOWN SLOUGH 20 830819 .10 1.00 LARGE GRAVEL SHALL GRAVEL 6.4 9.2 ~UNKNOWN SLOUGH 20 830819 .10 1.00 SHALL GRAVEL.LARGE GRAVEL 6.0 9.2 6 UNKNOWN SLOUGH 20 830819 .90 LOS LARGE GRAVEL SHALL GRAVEL 1.1 9.2 1 UNKNOWN -.....J SLOUGH 20 830819 .SO 1.60 LARGE GRAVEL SHALL GRAVEL 8.1 9.6 8 UNKNOWNIco I SLOUGH 20 830904 .10 .SO 4.1 9 20\0 RUBBLE LARGE GRAVEL 6.8 PRESENT SLOUGH 20 830904 .90 .20 RUBBLE LARGE GRAVEL 6.~6.6 10 UNKNOWN SLOUGH 20 830904 1.10 .~O LARGE GRAVEL SHALL GRAVEL 6.9 6.S 11 UNKNOWN SLOUGH 21 (SLOUGH ONLY)830831 .40 .~O LARGE GRAVEL SHALL GRAVEL 4.8 ~.8 31 UNKNOWN SLOUGH 21 (SLOUGH ONLY)830831 .40 .10 LARGE GRAVEL SHALL GRAVEL 4.0 ~.9 32 UNKNOWN SLOUGH 21 (SLOUGH ONLY)830831 .40 0.00 RUBBLE SHALL GRAVEL 4.0 S.1 JJ UNKNOwN SLOUGH 21 (SLOUGH ONLY)830831 .~O .6S COBBLE BOULDER 4.3 6.1 34 UNKNOWN SLOUGH 21 (SLOUGH ONLY)830831 .60 .2 ~RUBBLE LARGE GRAVEL S.8 6.1 3S UNKNOWN SLOUGH 21 (SLOUGH ONLY)830831 .10 .H LARGE GRAVEL RUBBLE ~.O 6.0 36 UNKNOWN SLOUGH 21 (SLOUGH ONLY)830831 .60 .40 RUBBLE SHALL GRAVEL 4.1 6.0 31 UNKNOWN SLOUGH 21 (SLOUGH ONLY)830831 .3 S .2S COBBLE LARGE GRAVEL 4.5 6.3 38 UNKNOWN SLOUGH 21 (SLOUGH ONLY)830831 .80 .05 RUBBLE LARGE GRAVEL 4.3 6.3 39 UNKNOWN SLOUGH 21 (SLOUGH ONLY)830831 .95 .08 RUBBLE LARGE GRAVEL 4.0 6.3 40 UNKNOWN SLOUGH 21 (SLOUGH ONLY)830831 .6S .10 COBBLE LARGE GRAVEL 4.1 6.0 41 UNKNOWN SLOUGH 21 (SLOUGH ONLY)830831 .65 .08 RUBBLE LARGE GRAVEL 4.1 5.9 42 UNKNOWN SLOUGH 21 (SLOUGH ONLY)830831 1.00 .03 RUBBLE LARGE GRAVEL 4.0 6.1 43 UNKNOWN --------------------------------------------------------------------------------------------------------------------------------- .....~-•.,------. Table 7 -&-1 Continued --------------------------------------------------------------------------------------------------------------------------------- WATER VELO-SUBSTRATE WATER TEMPERATURE (c)DISTANCE DEPTH CITY -------~-~------------------------------------REDD (FT)TO LOCATION OATE (FT)(FT/S)PRl MARY SECONDARY INTRAGRAVEL SURFACE NO.UPWELLING UPWELLING --------------------------------------------------------------------------------------------------------------------------------- SLOUGH 21 (SLOUGH ONLY)830831 .50 .10 LARGE GRAVEL RUBBLE 4.1 6.2 44 UNKNOWN SLOUGH 21 (SLOUGH ONLY)830831 .60 .50 RUIlBLE LARGE GRAVEL 4.2 6.1 45 PRESENT SLOUGH 21 (SLOUGH ONLY)830831 .50 .30 LARGE GRAVEL SHALL GRAVEL 4.3 6.2 46 UNKNOWN SLOUGH 21 (SLOUGH ONLY)830831 .80 .30 BOULDER SAND 4.2 6.2 47 UNKNOWN SLOUGH 21 (SLOUGH ONLY)830831 .65 .35 SHALL GRAVEL RUBBLE 4.1 6.0 48 UNKNOWN SLOUGH 21 (SLOUGH ONLY)830831 .65 .35 LARGE GRAVEL BOULDER 4.3 6.1 49 UNKNOWN '"'-J SLOUGH 21 MODELING SITE 830819 1.20 .08 RUBBLE LARGE GRAVEl.3.9 8.2 1 PRESENT 6I OJ SLOUGH 21 MODELING SITE 830819 1.90 .05 COBBLE RUBBLE 4.3 8.9 2 UNKNOWNI t-'SLOUGH 21 MODELING SITE 830819 .90 .09 COBBLE RUBBLE 4.8 7.5 3 PRESENT 15 0 SLOUGH 21 MODELING SITE 830819 1.20 .09 LARGE GRAVEL RUBBLE 3.7 7.4 4 PRESENT 4 SLOUGH 21 MODELING SITE 830819 1.20 .20 RUBBLE LARGE GRAVEL 3.8 5.7 5 PRESENT 5 SLOUGH 21 MODELING SITE 830819 .50 .10 COBBLE RUBBLE 3.6 5.7 6 PRESENT 3 SLOUGH 21 MODELING SITE 830819 1.60 .12 COBBLE RUBBLE 4.2 8.7 7 UNKNOWN SLOUGH 21.MODELING SITE 830819 1.20 .32 COBBLE RUBBLE 3.8 9.1 8 UNKNOWN SLOUGH 21 MODELING SITE 830819 1.20 .25 LARGE GRAVEL RUBBLE 3.8 9.5 9 UNKNOWN SLOUGH 21 MODELING SITE 830819 .80 .50 RUBBLE LARGE GRAVEL 4.4 9.5 10 UNKNOWN SLOUGH 21 MODELING SITE 830819 .80 .42 RUBBLE LARGE GRAVEL 4.7 9.7 11 UNKNOWN SLOUGH 21 MODELING SITE 830819 1.20 .40 RUBBLE LARGE GRAVEL 5.3 9.7 12 UNKNOWN SLOUGH 21 MODELING SITE 830819 1.10 .40 RUBBLE LARGE GRAVEL 4.0 9.1 13 UNKNOWN SLOUGH 21 MODELING SITE 830819 .80 .40 RUBBLE LARGE GRAVEL 4.5 9.0 14 UNKNOWN SLOUGH 21 MODELING SITE 830819 1.52 .10 LARGE GRAVEL RUBBLE 4.4 8.9 15 UNKNOWN SLOUGH 21 MODELING SITE 830819 1.00 .10 RUBBLE LARGE GRAVEL 4.4 10.5 16 PRESENT 3 SLOUGH 21 MODELING SITE 830819 2.30 .15 COBBLE -RUIlBLE 3.9 9.0 17 PRESENT 18 SLOUGH 21 MODELING SITE 830819 .92 .20 RUBBLE LARGE GRAVEL 4.6 8.6 18 UNKNOWN SLOUGH 21 MODELING SITE 830819 .90 .12 RUBBLE COBBLE 4.1 8.7 19 UNKNOWN --------------------------------------------------------------------------------------------------------------------------------- J ;J I ]I j I I I J J j I I J I B 1 C~1 1 ]cJ I ]C]-1 cc-1 --]1 J J ] ••__~~___~••__._~___•__•_____•_____,_~.~__._-.0"_..••__~._._____"_.~.___~________,__>_"_.,___'..__•__~__.___._".~_·___.______or __'•._~<_,_,____.,_..'_____~....___ Table 7-la-l Continued -----------------------------------------------------------------------------------------------------_._------------------------- WATER VELO-SUBSTRATE WATER TEMPERATURE (C)01 STANCE DEPTH CITY ----------------------------------------------REDO (FT)TO LOCATION DATE (FT)(FT/S)·PRlMARY SECONDARY 1NTRAGRA VEL SURFACE NO.UPWELLING UPWELLING --------------------------------------------------------------------------------------------------------------------------------- SLOUGH 21 MODELING SITE 830819 .75 .2 :i LARGE GRAVEL RUBBLE 4.6 9.5 20 UNKNOWN SLOUGH 21 MODELING SITE 830819 1.12 .32 LARGE GRAVEL RUBBLE 4.3 9.0 21 UNXNO\lN SLOUGH 21 MODELING SITE 830819 1.15 .22 LARGE GRAVEL RUBBLE 4.7 8.8 22 UNKNOWN SLOUGH 21 MODELING SITE 830819 2.40 .09 SMALL GRAVEL RUBBLE 5.5 11 .0 23 UNXNOWN SLOUGH 21 MODELING SITE 830819 1.70 .09 SMALL GRAVEL RUBBLE 4.5 10.0 24 UNKNOWN SLOUGH 21 MODELING SITE 830819 1.40 0.00 SMALL GRAVEL LARGE GRAVEL 4.7 10.6 25 UNKNOWN SLOUGH 21 MODELING SITE 830819 1.19 .10 SMALL GRAVEL LARGE GRAVEL 5.3 10.2 26 UNKNOWN "'"'-J SLOUGH 21 MODELING SITE 830819 1.73 .10 LARGE GRAVEL RUBBLE 5.6 11.0 27 .UNXNO\lNI OJ SLOUGH 21 MODELING SITE 830819 1.19 .09 RUBBLE SMALL GRAVEl.4.3 10.9 28 UNKNOWNI830819.60f-'SLOUGH 21 MODELING SITE .20 LARGE GRAVEL RUBBLE 5.4 10.4 29 UNKNOWN I-'SLOUGH 21 MODELING SITE 830819 1.10 .20 RUBBLE LARGE GRAVEL 4.1 9.2 30 PRESENT 15 SLOUGH 21 SIDE CHANNEL 830824 1.10 4.30 RUBBLE COBBLE 6.7 9.2 1 PRESENT SLOUGH 21 SIDE CHANNEL 830824 1.10 2.60 COBBLE RUBBLE 7.1 9.1 2 PRESENT SLOUGH 22 830819 .50 .65 LARGE GRAVEL SMALL GRAVEL 5.8 7.4 1 UNKNOWN SLOUGH 22 830819 .60 .60 LARGE GRAVEL RUBBLE 6.2 7.5 2 UNKNOWN SLOUGH 22 830819 .80 .:i5 RUB BLE LARGE GRAVEL 6.1 7.0 3 UNKNOWN SLOUGH 22 830819 1.00 .55 RUBBLE COBBLE 5.2 6.9 4 UNKNOWN SLOUGH 22 830819 1.20 .50 RUBBLE COBBLE 5.9 7.0 5 UNXNOWN SLOUGH 22 830819 1.00 .55 LARGE GRAVEL RUBBLE 5.2 7.1 6 UNXNOWN SLOUGH 22 830819 1.00 .5:i RUBBLE COBBLE 5.1 8.6 7 UNKNO\lN SLOUGH 22 830819 1.20 .55 LARGE GRAVEL COBBLE 5.8 8.6 8 UNKNOWN SLOUGH 22 8)0819 1.10 .:i5 RUBBLE LARGE GRAVEL 6.1 8.9 9 UNXNO\lN SLOUGH 22 830819 1.70 .55 COBBLE BOULDER 5.6 9.2 10 UNKNOWN SLOUGH 22 830819 1.90 .5:i COBBLE RUBBLE 5.6 9.2 11 UNXNOWN --------------------------------------------------------------------------------------------------------------------------------- Tab le 7 -8-1 Continued ...~._~.-.--._--~.....'_._"--'-"'-'._._._~,_.~-~.~-..--'---.-._.-..-_._--_..~'"~-~----~._._...-,-~--~.~. --------------------------------------------------------------------------------------------------------------------------------- LOCATION DATE DEPTH (FT) \.lATER VELO- CITY (FT/S) SUBSTRATE WATER TD-IPERATURE (C) --~-------------------------------------------REDOPRI~RY SECONDARY INTRAGRAVEL SURFACE NO.UPWELLING DISTAnCE CrT)TO UP\.IELLlNG '-J I o:J I t---' i-:J SLOUGH 22 830819 1.70 .55 COBBLE RUBBLE 5.3 9.4 12 UNKNOWN )J ,J I I J B B )J ....!J I J l J I ]1 -'I ")-,-1 J ])1 _.._"'"'_.__________.•__........__...._.__.,....__0 ,__•.••._~~...~._._.~•..._..~__'."__"~_'_·.'._.•_.•·,._·'.·_M_·.'••~,_._r_'_>__",_~, •__" .__~.~• _ Table 7-a-~Habitat data collected at sockeye salmon redds. --------------------------------------------------------------------------------------------------------------------------------- WATER VELO-.SUBSTRATE WATER TEMPERATURE (c)DISTANCt DEPTH CITY ----------------------------------------------REDD (FT)TO LOCATION DATE (FT)(FT/s)PRIMARY SECONDARY INTRAGRAVEL SURFACE NO.UPWELLING UPWELLING --------------------------------_.-----------------------------------------------------------_.---------------------------------- SLOUGH 8A W.FORK BI L TR.11 830909 .60 RUBBLE COBBLE 5.9 10.4 1 UNKNOWN SLOUGH 8A W.FORK BI L !R.,11 830909 .70 RUBBLE COBBLE 5.7 10.5 2 UNKNO'rIN SLOUGH 8A W.FORK BIL TR.11 830909 .75 LARGE GRAVEL COBBLE 4.7 7.2 )UNKNOWN SLOUGH 8A 1/.FORK BIL TR.11 830909 .90 LARGE GRAVEL RUBBLE 6.6 9.3 4 UNKNOWN SLOUGH 8A W.FORK BIL TR.11 830909 .70 LARGE GRAVEL RUBBLE 5.0 9.3 5 UNKNOWN --.J SLOUGH 8A W.FORK BIL TR.11 830909 .60 RUULE COBBLE 6.5 9.8 6 UNKNOWN I SLOUGH 8A W.FORX BI L TR.11 830909 .60 LARGE GRAVEL RUBBLE 5.1 9.8 7 UNKNOWNOJ I SLOUGH 8A W.FORK BIL TR.11 830909 .60 RUBBLE COBBLE 4.4 9.5 8 UNKNOWN.....SLOUGH 8A U.FORK BIL TR.11 830909 .40 RUBBLE BOULDER 5.0 8.8 9 UNKNOWNw SLOUGH 8A W.FORK BI L TR.11 830909 .90 SMALL GRAVEL LARGE GRAVEL 5.7 8.0 10 UNKNOWN SLOUGH 8A W.FORK BIL TR.#1 830909 1.00 LARGE GRAVEL RUBBLE 6.1 7.9 11 UNKNOWN SLOUGH 8A W.;ORK BIL TR.11 830909 1.50 RUBBLE COBBLE 6.5 8.9 12 UNKNOWN SLOUGH 8A W.FORK BI L TR.11 830909 1.00 LARGE GRAVEL RUBBLE 5.1 8.9 13 UNKNOWN SLOUGH SA W.FORJ(BIL TR.#1 830909 1.00 LARGE GRAVEL RUBBLE 5.3 8.7 14 UNKNOWN SLOUGH 8A 1/.FORK BIL TR.11 830909 1.10 RUBBLE COBBLE 6.4 9.0 15 UNKNOWN SLOUGH 8A 1/.FORK BI L TR.11 830909 1.90 LARGE GRAVEL COBBLE 5.1 9.0 16 UNKNOWN SLOUGH 11 830910 1.68 0.00 IIUB BLE COBBLE 1 UNKNOWN SLOUGH 11 830910 1.10 0.00 SAND LARGt GIlAVEL 2 PREstNT 15 SLOUGH 11 830910 .92 0.00 RUBBLE COBBLE 3 UNKNOWN SLOUGH 11 830910 .92 .20 RUBBLE SAND 4 UNKNOWN SLOUGH 11 830910 .62 .70 LARGE GRAVEL SMALL GRAVEL 5 UNKNOWN SLOUGH 11 830911 2.00 0.00 RUBBLE COBBLE 6 UNKNOWN SLOUGH 11 830911 .60 0.00 LARGE GRAVEL SAND 7 UNKNOWN SLOUGH 11 830911 .50 0.00 RUBBLE LARGE GRAVEL 8 UNKNOWN ....._~c____•__••-----'..'---------~.--"._'-'---.---"- Table 7-8-6..Continued -------------------------------------------------------------------------------------------------------------------------------_. WATER VELO-SUBSTRATE WATER TEMPERATURE (c)DISTANCE DEPTH CITY ----------------------------------------------REDO (FT)TO LOCATION DATE (FT)(FT/S)PRIMARY SECONDARY I NTRAG RA VEL SURFACE NO.UPWELLING UPWELLING- -------------------------------------------------------------------------------------------------------------------------------- SLOUGH 11 830911 1.20 .10 RUBBLE LARGE GRAVEL 9 PRESENT SLOUGH 11 830911 .80 .05 LARGE GRAVEL NUBBLE 10 UNKNOWN SLOUGH 11 830911 .60 0.00 RUBBLE COBBLE 11 UNKNOWN SLOUGH 11 830911 1.30 0.00 LARGE GRAVEL RUBBLE 12 PRESENT SLOUGH 11 830911 1.60 0.00 RUBBLE LARGE GRAVEL 13 PRESENT SLOUGH 11 830911 1.30 0.00 LARGE GRAVEL SAND 14 PRESENT SLOUGH 11 830911 1.00 0.00 SMALL GRAVEL SAND 15 UNKNOWN '-l SLOUGH 11 830911 .10 0.00 LARGE GRAVEL RUBBLE 16 UNKNOWNI OJ SLOUGH 11 830911 .90 0.00 SHALL GRAVEL LARGE GRAVEL 11 UNKNOWNI......SLOUGH 11 830911 .60 0.00 SMALL GRAVEL RUBBLE 18 UNKNOWN .j:::, SLOUGH 11 830901 2.30 0.00 LARGE GRAVEL SHALL GRAVEL 4.0 4.9 1 UNKNOWN SLOUGH 11 830901 2,30 0.00 LARGE GRAVEL SHALL GRAVEL 4.5 5.0 2 UNKNOWN SLOUGH 21 (SLOUGH ONLY)830831 .40 .20 RUBBLE LARGE GRAVEL 5.0 5.6 2 UNKNOWN SLOUGH 21 (SLOUGH ONLY)830831 .40 .90 COBBLE LARGE GRAVEL 4.6 6.3 3 UNKNOWN SLOUGH 21 (SLOUGH ONLY)830831 .30 .01 RUBBLE LARGE GRAVEL 4.3 1.0 4 PRESENT SLOUGH 21 (SLOUGH ONLY)830831 .50 .10 LARGE GRAVEL SHALL GRAVEL 4.1 6.6 5 UNKNOWN SLOUGH 21 (SLOUGH ONLY)830831 .25 .30 LARGE GRAVEL SHALL GRAVEL 4.3 6.1 6 UNKNOWN SLOUGH 21 (SLOUGH ONLY)830831 .45 .20 BOULDER LARGE GRAVEL 4.0 6.4 1 UNKNOWN SLOUGH 21 (SLOUGH ONLY)830831 .50 0.00 BOULDER SHALL GRAVEL 4.1 5.1 8 PRESENT SLOUGH 21 (SLOUGH ONLy)830831 .80 .05 COBBLE LARGE GRAVEL 4.1 6.2 9 UNKNOWN SLOUGH 21 (SLOUGH ONLY)830831 .90 .15 RUBBLE LARGE GRAVEL 4.6 6.1 10 UNKNOWN SLOUGH 21 (SLOUGH ONLY)830831 .40 .40 RUBBLE LARGE GRAVEL 4.4 6.1 11 UNKNOWN SLOUGH 21 (SLOUGH ONLY)830831 .10 .15 BOULDER LARGE GRAVEL 4.1 6.1 12 UNKNOWN SLOUGH 21 (SLOUGH ONLY)830831 .10 .10 BOULDER LARGE GRAVEL 4.2 6.2 13 UNKNOWN -------------------------------------------------------------------------------------------------------------------------------- I ~...])!1 J )•)I J ~J I ~J I ]-~1 J .J J -~j --I J B ] Table 7-B-a...Continued --------------------------------------------------------------------------------------------------------------------------------- \,lATER VELO-SUBSTRATE WATER TEMPERATURE (c)DI STANCE DEPTH CITY r---------------------------------------------REDD (n)TO LOCATION DATE (FT)(fT/s)PRIMARY SECONDARY I NTRAGRA VEL SURFACE NO.UPWELLING UPWELLING --------------------------------------------------------------------------------------------------------------------------------- SLOUGH 21 (SLOUGH ONLY)830831 .50 .15 BOULDER SHALL GRAVEL 4.1 6.0 14 PRESENT SLOUGH 21 (SLOUGH ONLY)830831 .40 .1 S RUlIBLE LARGE GRAIIEL 4.5 6.1 IS UNKNOWN SLOUGH 21 (SLOUGH ONLY)830831 .40 .20 COllBLE LARGE GRAVEL 4.3 6.0 16 UNKNOWN SLOUGH 21 (SLOUGH ONLY)830831 .50 .25 COBlILE SMALL GRAVEL 4.3 6.2 17 UNKNOWN SLOUGH 21 (SLOUGH ONLY)830831 .40 .25 1I0ULDER LARGE GRAIIEL 4.1 6.3 18 UNKNOWN SLOUGH 21 (SLOUGH ONLY)830831 .50 .45 COllllLE LARGE GRAVEL 4~1 6.4 19 PRESENT SLOUGH 21 (SLOUGH ONLY)830831 .50 .45 LARGE GRAVEL SHALL GRAIIEL 4.6 6.1 20 UNKNOWN SLOUGH 21 HODELING SITE 830819 1.30 .15 RUBBLE COllllLE 4.0 8.7 1 UNKNOWN -....J I (J:l I....'un __ .... APPENDIX 7C Summary Of Statistics And Tests For Various Groupings Of Chum And Sockeye Salmon Utilization Histograms 7-C-1 Table 7-(-1 Summary of variance statistics and tests for various groupings for chum salmon util"ization depth histograms_ HISTOGRAM INCREMENT LABEL SIZE INCREMENT START VARIANCE df A 0.1 0.0 106.9729 28 B 0.2 0.0 405.8857 14 0.2 474.7967 13 ~C 0.1 0 121.3 121.0 892.9000 9 E 0.3 10.1 916.0111 9 F 0.3 0.2 828.8182 10 LEVENE"S TEST F STATISTIC 6.103012100 df 5,83 PROS ~, PAIRWISE COMPARISONS PAIR df F VALUE PROS A,S 14,28 3.794285 0.0013 A,C 13,28 4.438476 0.01211215 A,D 9,28 8.346974 0.0010 l2I A,E 9,28 8.563132121 0.000121 A,F 10,28 7.747927 10.012100 B,C 13,14 1.169779 0.390121 B,D 9,14 2.199880 0.109010 B,E 9,14 .2.256820 0.0830 B,F 1O,14 2.1041999 10.1100 C,O 9,13 1.880594 13.151010 C,E 9,13 1.9292710 0.1410121 C,F 110,13 1.745628 0.1700 D,E 9,9 1.025883 10.49010 D,F 9,1121 1.12177317 121.451010 E,F 9,10 1.105201 121.44100 7-C-2 --I ----~)1 ---]1 1-1 1 ], Table 7-C-2.Comparison of incremented mean and standard deviation values with non-incremented values for various groupings for chum salmon depth and velocity histograms. Percent Percent Deviation Deviation Non-From Non-Non-Fron Non- Histogram Incremented Incremented Incremented Incremented Incremented Incremented Variable Label Mean Mean Mean Stand.Dev.Stand.Dev.Stand.Dev. Depth A 0.97 1.11 12.6 0.53 0.52 0.9 (ft )B 1.07 1.11 3.7 0.53 0.52 0.8 C 0.89 1.11 19.6 0.51 0.52 2.9 ""-J D 1.09 1.11 1.4 0.56 0.52 7.1InE0.78 1.11 30.0 0.54 0.52 3.6IwF1.10 1.11 0.9 0.56 0.52 7.7 Velocity A 0.28 0.30 5.8 0.44 0.44 0.1 (ft/sec)B 0.29 0.30 2.5 0.43 0.44 1.4 C 0.46 0.30 56.7 0.44 0.44 0.1 0 0.30 0.30 1.3 0.43 0.44 1.2 E 0.57 0.30 94.7 0.46 0.44 3.7 F .0.30 0.30 2.3 0.44 0.44 0.7 G 0.31 0.30 4.7 0.43 0.44 1.7 Tabl e 7·C-$Summary of variance statistics and tests for various- groupings for chum salmon utilization velocity histograms. HIST06RAM INCREMENT LABEL SIZE INCREMENT START·VARIANCE df A 0.1 0.l2I 330.5182 44 B 0.1 0.1 605.9720 43 C 0.2 0.0 1114.7900 21 D 0.2 0.1 1289.5519 21 E 0.3 l2I.0 2004.1714 14 F 0.3 0.1 1949.3625 15 G 0.3 0.2 2948.0286 14 LEVENE"S TEST - F STATISTIC 3.09000121 df 6,172 PROB 0.0068 PAIRWISE COMPARISONS --~------------------------------------------ PAIR df F VALUE PROB - A,B 43,44 1.833400 0.0240 A,C 21,44 3.372855 0.0003 A,O 21,44 3.901606 0.001211 A,E 14,44 6.063725 0.0000 A,F 15,44 5.897898 0.0000 A,G 14,44 8.919414 0.0000 B,C 21,43 1.839672 0.0450 B,D 21,43 2.128072 0.0180 B,E 14,43 3.307366 0.0013 B,F 15,43 3.216918 0.0014 8,6 14,43 4.864958 0.0000 C,D 21,21 1.156767 121.3700 C,E 14,21 1.797802 121.11'1.10 C,F 15,21 1.748637 0.1200 e,G 14,21 2.644470 121.0220 O,E 14,21 1.554161 0.1800 D,F 15,21 1.511659 l2I.190121 0,6 14,21 2.286088 0.0150 E,F 14,15 1.028116 0.4800 E,G 14,14 1.470946 0.241210 F,G 14,15 1.512304 121.2200 7-(-4 - Appendix Table 7-C-4.Bivaraite correlation statistics for evaluating independence of habitat variables used in the development of suitability criteria curves for chum and sockeye salmon. Approximate Comparison n r Zd Probabil ity* Chum Depth Vs.333 -0.21 0.23 0.41 Velocity Substrate Vs.319 0.05 -2.65 1.0 F Depth Substrate Vs.319 -0.08 -2.26 0.99 """Velocity Sockeye Depth Vs.65 -0.28 0.65 0.26 Velocity Substrate Vs.81 -0.31 1.03 0.15 Depth Substrate Vs.65 0.09 -0.89 0.81 -Velocity *Probabilities associated with the hypothesis that Ho : p O.2l...... Note that low values ov probability lead to rejection of Ho . 7·C-5 Tabl e 7-C-s Summary of variance statistics and tests for various groupings for sockeye salmon utilization depth histograms. HISTOGRAM INCREMENT LABEL SIZE INCREMENT START VARIANCE df A 0.1 0.0 8.5385 26 B 0.2 0.121 29.1l2144 13 C 0.2 0.1 29.4121 13 D l2I.3 0.l2I 63.8778 9 E 121.3 0.1 61.4333 9 F l2I.3 0.2 53.7500 8 LEVENE"S TEST F STATISTIC 5.470121l21l21 df 5,78 PROB 0.12112102 PAIRWISE COMPARISONS PAIR A,S A,C A,D A,E A,F B,C B,D B,E B,F C,D C,E C,F D,E D,F E,F df 13,26 13,26 9,26 9,26 8,26 13,13 9,13 9,13 8,13 9,13 9,13 8,13 9,9 9,8 9,8 7-C-6 F VALUE 3.408623 3.444659 7.481181 7.194895 6.295045 1.l2I10572 2.194781 2.11121792 1.8468121121 2.171821 2.12188710 1.827480 1.03979121 1.188424 1.142946 PROB 0.012138 0.012135 0.0121121121 0.0121121121 0.0002 121.49121121 0.0960 0.110121 0.160121 0.l2I990 0.110121 0.160121 0.48121121 121.411210 121.43121121 ]1 ]1 j 1 1 1 J Table 7-C-6.Comparison of incremented mean and standard deviation values with non-incremented values for various groupings for sockeye salmon depth and velocity histograms. Percent Percent Deviation Deviation Non-From Non-Non-Fron Non- Histogram Incremented Incremented Incremented Incremented Incremented Incremented Variable Label Mean Mean Mean Stand.Oev.Stand.Dev.Stand.Dev. Depth A 1.00 1.04 3.2 0.64 0.62 2.4 (ft )B 1.01 1.04 2.8 0.65 0.62 3.6 C 1.00 1.04 3.6 0.63 0.62 1.8 -.....J D 1.01 1.04 2.7 0.64 0.62 2.1, n E 1.00 1.04 3.8 0.66 0.62 5.9I -.....J F 1.01 1.04 3.1 0.63 0.62 1.7 Velocity A 0.15 0.17 10.4 1.00 0.99 0.3 (ft/sec)B 0.17 0.17 1.7 0.99 0.99 0.1 C 0.34 0.17 100.2 0.95 0.99 4.5 D 0.16 0.17 2.7 0.99 0.99 0.1 E 0.43 0.17 153.7 0.91 0.99 8.3 F 0.18 0.17 8.3 0.99 0.99 0.3 G 0.19 0.17 14.3 0.99 0.99 0.5 Tabl e 7-'-7 Summary of variance statistics and tests for various groupings for·sockeye salmon utilization velocity histograms. HISTOGRAM LABEL INCREMENT SIZE INCREMENT START VARIANCE df A 121.1 121.0 50.2778 9 B 0.1 0.1 136.1944 8 C 0.2 0.0 113.3667 5 0 0.2 0.1 223.012100 4 E 121.3 0.121 217.5833 3 F o -"121.1 250.9167 3....,) G 121.3 0.2 452.9167 3 LEVENE~S TEST - -~ F STATISTIC 1.250000 7-C-8 df 6,35 PROB t21.3l2135 .... - - - - Appendix 7-0 Weighted Usable Area Projection Data 7-D-1 Appendix Table 7-0-1.Projections of gross area and WUA (ft 2/1000 ft)of chum ad sockeye salmon spawning habitat at Slough 8A. Chum Sockeye Site Flow Mainstem Discharge WUA Gross WUA Gross (cfs)(cfs) 5 --2363 66218 3713 66218 10 --3285 68778 4451 68778 15 --3975 69863 4833 69863 20 --4549 70912 5272 70912 25 --5438 74188 6042 74188'-J I 30 --5900 75248 6572 752480 I 35 --6240 76142 7066 76142N 40 --6486 77064 7486 77064 45 --6782 77938 7810 77938 50 --7126 78754 8001 78754 60 33565 7749 80273 8279 80273 70 34700 8316 81711 8398 81711 site flow not controlled by mainstem discharge J J B I i ]1 I ~J I I I J J I I J ---._.]-~··l 1 j ]j ]1 1 -]1 ] Appendix Table 7-0-2.Projections of gross area and WUA (ft 2/1000 ft)of chum and sockeye salmon spawning habitat at Slough 9. Chum Sockeye Site Flow Mainstem Discharge WUA Gross WUA Gross (cfs)(cfs) 5 --2367 64481 5011 64481 10 19209 4327 70947 6089 70947 15 20089 5594 74170 6356 74170 20 20737 6277 78065 6508 78065 25 21254 6702 80268 6625 80268 ""-J 30 21687 6966 83525 6702 83525I 0 35 22059 7135 85352 6727 85352Iw4022387724687186674287186 45 22680 7365 88402 6762 88402 50 22945 7481 89986 6781 89986 60 23412 7707 92398 6829 92398 70 23814 7910 96544 6895 96544 80 24167 8107 98312 6946 98312 90 24484 8244 100229 6992 100229 100 24770 8378 101929 7014 101929 125 25388 8679 105280 6959 105280 150 25905 8925 108189 6823 108189 175 26349 9062 110150 6677 110150 200 26741 9030 111734 6571 111734 250 27408 8965 114982 6393 114982 300 27965 8591 118473 6081 118473 350 28446 8168 120769 5543 120769 400 28868 7643 122670 5172 122670 450 29246 7051 124344 4840 124344 500 29588 6429 128544 4487 128544 550 29901 5982 129888 4131 129888 600 30190 5603 131216 3848 131216 --site flow not controlled by mainstem discharge Appendix Table 7-0-3.Projections of gross area and WUA (ft 2/1000 ft)of chum and sockeye salmon spawning habitat at Slough 21. Chum Sockeye Site Flow Mainstem Discharge WUA Gross WUA Gross (cfs)(cfs) 5 --5231 48143 6821 48143 10 24127 .8453 55374 9179 55374 15 25007 10134 58055 10772 58055 20 25651 11175 58996 12235 58996 25 26162 12064 60280 13136 60280 -....J 30 26587 12885 60942 13544 60942I CJ 35 26951 13774 62571 13640 62571I +::>40 27271 14609 65457 13726 65457 45 27556 15323 67779 13714 67779 50 27814 15840 70378 13611 70378 60 28266 16430 71364 13271 71364 70 28653 16433 73227 12869 73227 80 28993 16171 75853 12420 75853 90 29297 15851 77232 11906 77232 100 29571 15485 78424 11413 78424 200 31438 11512 86757 7382 86757 300 32585 8674 89749 5032 89749 400 33424 6636 92325 3533 92325 --site flow not controlled by mainstem discharge )I J I )...~I )J t I J l I J .J )I J -1 1 ·1 J ]J I l 1 ]- -j ] Appendix Table 7-0-4.Projections of gross area and WUA (ft 2/1000 ft)of chum and sockeye salmon spawning habitat at Upper Side Channel 11. Chum Sockeye Site Flow Mainstem Discharge WUA Gross WUA Gross 5 --3287 55198 5198 55198 10 --4769 64423 7328 64423 15 --5899 70364 9142 70364 20 --6968 74134 10516 74134 25 16035 8186 78120 11319.78120 30 16622 9208 81321 12130 81321 -.....J 35 17135 10115 85287 12723 85287I 0 40 17592 10818 86115 13066 86115I U1 45 18005 11329 86902 13296 86902 50 18383 11794 87618 13389 87618 60 19056 12531 91321 13624 91321 70 19644 13087 94446 13876 94446 80 20168 13371 96357 14209 96357 90 20641 13511 99027 14429 99027 100 21075 13705 100245 14335 100245 110 21474 13933 103388 13950 103388 120 21846 14066 104770 13576 104770 130 22193 14204 106149 13151 106149 140 22520 14334 107433 12713 107433 150 22828 14414 108614 12247 108614 175 23533 13990 111336 11122 111336 200 24160 13354 113641 10234 113641 225 24728 12762 115707 9513 115707 250 25247 12142 117635 8902 117635 --site flow not controlled by mainstem discharge ----,---~--~-._--------_..._.._•._-._._._,...,-~_._,,,--_..._--_..~,,-- Appendix Table 7-0-5.Projections of gross area and WUA (ft 2/1000 ft)of chum and sockeye salmon spawning habitat at Side Channel 21. Chum Sockeye Site Flow Mainstem Discharge WUA Gross WUA Gross (cfs)(cfs) 20 --2057 106368 4288 106368 25 --2288 109661 4523 109661 30 --2510 113907 4699 113907 35 --2764 115687 4766 115687 40 --3001 118383 4797 118383'-l I 45 --3231 120994 4755 1209940 I 50 --3434 126143 4694 126143CJ) 60 --3744 128198 4454 128198 70 --3856 131926 4217 131926 80 12208 3846 134739 3963 134739 90 12671 3773 137226 3712 137226 100 13100 3688 139614 3495 139614 110 13501 -3719 144085 3413 144085 120 13878 3683 145555 3287 145555 125 14058 3656 146260 3225 146260 130 14233 3628 147685 3167 147685 150 14892 3491 151934 2949 ,151934 175 15636 3307 154915 2703 154915 200 16310 3094 157407 2481 157407 225 16929 2871 163901 2281 163901 250 17502 2662 167758 2097 167758 275 18037 2469 172210 1927 172210 300 18540 2290 179309 1771 179309 350 19466 ]971 188071 1488 188071 400 20306 1762 195412 1243 195412 450 21076 16]8 198723 1037 198723 --site flow not controlled by mainstem discharge ,~I )J ~J I )~1 !J J )I .1 ~ ]I 1 1 --1 -J -]-)1 Appendix Table 7-0-5.Continued. Chum Sockeye Site Flow Mainstem Discharge WUA Gross WUA Gross (cfs)(cfs) 550 22456 1412 209182 813 209182 600 23083 1325 211216 747 211216 700 24235 1172 213197 640 213197 800 25280 1191 216461 1046 216461 900 26240 1274 221721 1873 221721 1000 27128 1382 226073 2792 226073 -....J 1100 27958 1620 231116 3446 231116 I 1200 28738 2171 233790 3548 233790Cl I 1300 29474 2719 242382 3622 242382-....J 1400 30173 3249 245228 3695 245228 1500 30838 3760 248203 3718 248203 Appendix Table 7-0-6.Projections of gross area and WUA (ft 2/1000 ft)of chum and sockeye salmon spawning habitat at Side Channel 10. Chum Sockeye Site Flow Mainstem Discharge WUA Gross WUA Gross (cfs)(cfs) 5 --0 44519 0 44519 10 --241 51396 587 51396 15 19904 668 57069 1911 57069 20 20585 1049 60975 3291 60975 "-J 25 21130 1377 63253 4654 63253 I 30 21586 1675 64655 .5715 646550 I 35 21979 2034 66581 6485 6658100 40 22325 2400 67914 7017 67914 50 22916 3273 70782 7305 70782 60 23410 4065 73925 7106 73925 70 23836 4727 78243 6624 78243 90 24547 5738 85177 5796 85177 100 24852 6068 88501 5588 88501 ~-site flow not controlled by mainstem discharge 5 __J I I )I I J I ~I J J I .J I I J 1 1 ~·l '1 1 .-)····1 I 1 Appendix Table 7-0-7.Projections of gross area and WUA (ft2/1000 ft)of chum and sockeye salmon spawning habitat at Lower Side Channel 11. Chum Sockeye Si te Flow Mainstem Discharge WUA Gross WUA Gross (cfs)(c fs) 400 5901 9218 204918 9513 204918 500 6817 9590 224059 9302 224059 600 7671 9822 242666 8892 242666 700 8475 1-0064 260310 8551 260310 800 9239 10170 266575 8251 266575 ........,900 9971 10149 271267 7979 271267I 0 1000 10674 9931 275754 7743 275754I \.0 1200 12010 9458 292958 7217 292958 1400 13269 8986 296307 6759 296307 1600 14466 8509 299213 6318 299213 1800 15612 8061 301882 5903 301882 2000 16713 7686 304367 5558 304367 - - APPENDIX 7E Flow Chart And Outline Of Salmon Spawning Habitat Analysis 7-E-l ALASKA DEPARTMENT OF FISH AND GAME I SU HYDRO AQUATIC HA81TAT AND INSTREAM FLOW {A H] FY 8 4 AP PROACH FOR EVALUATING SALMON SPAWNING HA81TAT UTILIZATION IN SLOUGHS AND SIDE CHANNELS FLOW R,l,.In ',,,II;n~,n .D,.~.~<t" r- I I L .••" •...-D~..."<>'n-.,l,,•.,•• [=:::J -H,,~,'ar UI,J'I,u",n ~I~dl c:J -rn~~I.:',~:"~~:;:':~~"'G~ c:J -H"~lf"l :,j,Cf'.HY ::;1~dT ~I - Appendix Figure 7-E-l.Flow diagram of salfl10n spawning habitat analysis. 7-E-2 - - I~",.-....;~t- ~ i I ~ I - - FLOW CHART ATTACHMENT ALASKA DEPARTMENT OF FISH AND GAME/SU HYDRO AQUATIC HABITAT AND INSTREAM FLOW (AH) FY 84 APPROACH FOR EVALUATING SALMON SPAWNING HABITAT UTILIZATION IN SLOUGHS AND SIDE CHANNELS r.Availability Model Assessment (Includes An Assessment Of Flow Related Velocity,Depth,And Substrate Characteristics.)1 A.Hydraulic Model Data Sites. 1)Slough Models (IFG-4) a)Slough 8A b)Slough 9 c)Slough 21 2)Side Channel Models (IFG-4) a)'Side Channel 10 b)Upper Side Channel 11 c)Side Channel 21 3)Side Channel Model (IFG-2) a)Lower Si de Channel 11 B.Calibration by EWT&A and ADF&G. C.Evaluate Whether Model Output Corresponds To The Range Of Flows Which Occurred When Spawning Habitat Utilization Conditions Were Measured. 1)Determine slough flows which occurred during the periods when redd measurements were recorded at each modeling site (see II-A-2). 1 See also IV-2 7-E-3 FLOW CHART ATTACHMENT 2)Determine if hydraulic model output for these flows can be generated in order to determine available depth,velocity,and substrate characteristics,or whether additional data must be collected. D.Collect The Following FY85 Availability Data If Required: 1)velocity,depth,and substrate; 2)surface and intragravel water temperature;and, 3)upwelling presence or absence. E.Develop Scatter Plots Of Available Habitat Which Illustrate Depth Versus Velocity With Substrate Indicated As Acceptable (+)Or Unacceptable (-). 7-E -I-j ...., .... - - - - ,.. FLOW CHART ATTACHMENT II.Spawning Habitat Utilization Assessment (Includes An Assessment Of Point Specific Velocity,Depth·,Substrate,Temperature And Upwelling" Characteristics At Redd Locations.) A.Spawning Habitat Utilization Data Base Source Evaluation To Assess Which Spawning Habitat Utilization Data Sets Can Or Should Be Used And/Or Combined To Develop Adult Salmon Spawning Habitat Curves. 1)Sites and data sets are listed below.Number in parenthesis indicates the number of redd observations.An asterisk (*) indicates that a hydraulic model is available for the site. Chum Sockeye 1982 Field Data -Slough 9*(45) -Slough 8A*(37) -Slough 21*(34) -Slough 11 (15) 1983 Field Data -Slough 9*(31) -Slough 8A*(15) -Slough 21*(49) -Side Channel 21*(2) -Upper Side Channel 11*(2) -Slough 11 (15) -Other sloughs (sloughs 9A(24), 17(6),20(11),22(12)] -Mouth of 4th of July Creek (28) -Mouth of Indian River (3) 1982 Fi e 1d Data -510ugh 8A*(l) -Slough 11 (23) 1983 Field Data -Slough 8A*(I6) -Slough 21*(20) -Slough 11 (22) -Slough 17 (2) (136) (125) 1983 Field Data -Portage Creek -Indian River 1982 and 1983 Field Data -Insufflclent Data (is) Coho 1982 and 1983 Field Data -Insufflclent Data to) Pink Chinook -! i Other Literature Data -Bradley Lake -Terror Lake -Chakachamna -Willow Creek-Other sources if available .FLOW CHART ATTACHMENT 2)Compile spawning habitat utilization data from ADF&G Su Hydro mOdeling sites (*)and reduce above data into a scatter plot format for evaluation and overlay on scatter plots of ~vai1ab1e habitat from section I-E above.,~ a)Scatter plots of spawning habitat utilization data wi 11 be developed which illustrate:-i)depths vs velocities with acceptable {+}or unacceptable substrate (-);-in depths vs differences in surface and intragrave1 water temperature and; iii)depths vs velocities with upwelling presence (+)~or absence (-). b)Spawning habitat utilization scatter plots from a-i above will be overlayed on scatter plots of available habitat from I-E above. 3)Evaluate trends shown by scatter plots. 4)Evaluate whether spawning habitat utilization data from modeling sites above {II-A-2}are sufficient to develop adequate curves; or,will it be necessary to combine these data with non-modeling site (II-A-5)and/or literature data (I-A-6)?If data are sufficient,continue to Step II-A-7 or if insufficient proceed to step II-A-5 following solid line processes only .. 5)Compile ADF&G spawning habitat utilization data for non-modeled sites to evaluate whether these data can be combined with data from modeling sites for use in developing spawning habitat curves. a)Develop scatter plots of non-modeling sites data. b)Evaluate trends shown by scatter plots. c)Compare the above (II-A-5-a)spawning habitat utilization scatter plots to scatter plots of ADF&G Su Hydro modeling sites (II-A-2)to determine whether these data can be combined;and,if so,continue to step 5-d.If the data can not be combined,proceed to step II-A-6 to evaluate the use of literature data. d)Determine if the combined data bases are adequate and if they are,continue to step II-A-7.If they are insufficient,proceed to step II-A-6 to consider the use of literature data. 6)Compile spawning habitat utilization data from literature sources to evaluate whether these data can be combined with data from modeling sites for use in developing habitat curves. 7-E-G - --...~.~-Q--_.'••- FLOW CHART ATTACHMENT .... - a)Develop scatter plots of literature data. b)Evaluate trends shown by scatter plots . c)Compare the above (II-A-6-a):spawning habitat utilization scatter plots to scatter plots of ADF&G Su Hydro modeling sites (II-A-2)to determine whether these data can be combined and if so continue to step 6-d.If they cannot be combined,additional field data must be collected if FY85 (II-A-10). d)Determine if the combined data bases are adequate and if they are,continue to step II-A-7.If they are insufficient,collect additional field data in FY85 (II-A-lO). 7)Overlay utilization scatter plots of temperature and upwelling from II-A-2-a-ii and iii above and velocity,depth and substrate scatter plots of utilized and available spawning habitat from II-A-2-b (II-A-5-d and II-A-6-d data would also be included if these loops were required)above. 8)Evaluate trends shown by these scatter plots to determine if temperature and/or upwelling are limiting.If they are limiting,proceed to step II-A-9 and if not,continue to II-B. 9)Evaluate whether a portion or all of the: a)temperature,upwell ing,velocity,depth and substrate ~pawning habitat utilization data are adequate; r b)whether temperature and upwelling availability data are requ ired;and ~c)whether to continue to the combined step II-A-10 and 1-0 or to II-B. 10)Collect FY85 spawning habitat utilization data if required: a)velocity,depth and substrate; B. b)surface and intragravel water temperature;and c)upwelling presence or absence. Evaluate Whether the Following Approaches or a Combination of Them Can or Should Be Used to Develop Spawning Habitat Curves: Standard U.S.Fish and Wildlife Service IFG approach (Bovee and Cochnauer 1977); -Baldrige and Amos (1982); -Voos (1980; Prewitt (1982); -ADF&G (1983)AH technique;and -Other possible approaches or combinations of the above. 7-E-7 ·-._~-'-:-. FLOW CHART ATTACHMENT C.If data base appears adequate continue to step 11-0;if data are. inadequate.proceed"to step II-A-5 following solid line process only.This only applies if II-A-5 and II-A-6 were not incorporated into development of curves at step II-A-4. .j D.Develop Spawning Habitat Curves.. E.'If data from II-A-5 and II-A-6 Were Not Incorporated Into Initial Development Of Curves Proceed to Step II-A-5 Following Dashed Line Processes Only To Determine If These Data Can Be Used To Refine Curves.If Previously Used Or If 'It Is Detennined That These Data Should Not Be Used For This Purpo~e.Continue To Step III-A. 7-E-8 .... - - ·FLOW CHART ATTACHMENT III.Habitat Model [Combination of Spawning Habitat Curves and Calibrated Hydraulic Models To Oet~rmine Weighted Usable Area (WUA)] A.Evaluation of Linkage Approaches of Spawning Habitat Curves with Hydraulic Models. 1)WUA Calculation Technique Evaluation a)IFG WUA calculations: i)standard calculation with three matrices iO lowest limiting factor iii)Geometric mean b)Multi-variate calculation 2)Consider calculation of WUA using optimum,preferred, utilized,and available categories of AOF&G AH,1983 analysis. B.Use Habitat Model to Generate WUA. 7-E-q ·FLOW CHART ATTACHMENT IV.Miscellaneous (These Items Are Not Included In Flow Chart.) 1)Assess whether spawning habitat utilization behavior criteria can be evaluated and combined with other spawning habitat utilization data,i.e.,Fanning (F),Quivering (Q),Aggression (A)and Holding (H).This task has been assigned a low priority but may be useful for determi ni ng Uoutli ers li in spawni ng habi tat utilization data sets (II-A-3). 2}Availability data sets for temperature and upwelling are not available.Cost effective methods for collecting and analyzing these data are being evaluated in the event it is necessary to input these data into the model in the future. 3)The evaluation of tributary mouth hydraulic and spawning habitat availability and utilization data will be treated independently of this analysis. 4)Develop changes in hydraulic and habitat models to enable the RJ staff to incorporate juvenile habitat data for their analysis. 7 -E-IO mm, - A technique for determining fish A comparison between habitat American Fisheries Society,Portland. - - 'FLOW CHART ATTACHMENT Bib 1i ography Alaska Department of Fish and Game (ADF&G).1983a.Susitna Hydro Aquatic Studies,Phase II basic data report;Vol.4"Appendix B.ADF&G Su Hydro Aquatic Studies Program.Anchorage,Alaska. 1983b.Susitna Hydro Aquatic Studies.Phase II report;Synopsis of the 1982 aquatic studies and analysis of fish and habitat relationships.Appendix D.AOF&G Su Hydro Aquatic Studies Program. Anchorage.Ataska. Baldrige,J.E.,and D.Amos.1981. habitat suitability criteria: utilization and availability. Oregon. Bovee,K.D.,and T.Cochnauer.1977.Development and evaluation of weighted criteria,probabi1ity-of-use curves for instream flow assessments:fisheries.Instream Flow Information Paper No.3. Cooperative Instream Flow Group,Fort Collins.Colorado. Prewitt.C.G.1982.The effect of depth-velocity correlations on aquatic physical habitat usability estimates.Ph.D.Thesis.Colorado State University.Fort Collins,Colorado. Voos.K.A.1981.Simulated use of the exponential polynomial/maximum likelihood technique in developing suitability of use functions for ,~fish habitat.Ph.D.Thesis.Utah State University,Logan.Utah. 7-E-O