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HomeMy WebLinkAboutSuWa Talkeetna to devil canyon river 1985< o'?RZAcEBASCO 4 F472 *no.2945 SUSITNA , HYDROELECTRIC PROJECT FEDERAL ENERGY REGULATORY COMMISSION | PROJECT No.7114 co ||5000444612-ND3375|aceeeee_RESPONSE OF AQUATIC HABITAT SURFACE AREAS TO ©MAINSTEM DISCHARGEIN THE TALKEETNA-TO-DEVIL_CANYON SEGMENT OF THE SUSITNA RIVER,ALASKA | PREPARED BY Bet Trihey&_ fiele-"S-Associates |Oe |7 | ,||a S a | Aquatic Resource | ' |7 | a FINAL REPORT Specialists || . . | ||ee NNER CONTRACT TO a . |_NOVEMBER 1985 1425,TNA JOINT VENTURE | } a |DOCUMENT No.2945 {1 $8 . . . | . | Alaska Power Authority EeBeewtcd|warcwnrtdZe|enedirewsacsasKroner20thbeARLIS ;Alaska ResourcesLibrary&Information ServicesAnchorage,Alaska SUSITNA HYDROELECTRIC PROJECT Response of Aquatic Habitat Surface Areas to Mainstem Discharge [n the Talkeetna-to-Devil Canyon Segment of the Susitna River,Alaska By Sharon A.Ki inger-Kingsley LaMoyne Reynolds E.Woody Trihey Trihey and Associates Under Contract To Harza-Ebasco Susitna Joint Venture Prepared For Alaska Power Authority Final Report November 1985 ARLISAlaskaResourcesLibrary&Information ServicesLibraryBuilding,Suite 1113211ProvidenceDriveAnchorage,AK 99508-4614 Document No.2945 Susitna File No.4.3.1.3 OVRAALD TK INAS Sy FUL NO.Quy a4 Fy cS 33 it NOTICE ANY QUESTIONS OR COMMENTS CONCERNING THIS REPORT SHOULD BE DIRECTED TO THE ALASKA POWER AUTHORITY SUSITNA PROJECT OFFICE. 33755000444612ACKNOWLEDGEMENTS This work was undertaken In cooperation with the Alaska Department of Fish and Game Susitna Hydro Aquatic Study Team and R &M Consultants, Inc.,Anchorage,Alaska.ADF &G SuHydro personnel participated in the derivation of definitions for the various habitat types and the development of the aquatic habitat classification key.The aerial photography misslons were scheduled through Mr.Steve Bredthauer,R&M Consultants,Inc.He did an exceptional job given the highly varfable nature of streamflow and weather conditions.Aerial photography was flown and photo mosaics and enlargements prepared by Air Photo Tech, Inc.,and North Pacific Aerfal Surveys,Inc.,Anchorage,Alaska,under contract to the Harza-Ebasco Susitna Jofnt Venture. TABLE OF CONTENTS Page INTRODUCTION..0.cccecesceesseceecesseveeceesseesesensesceneess METHODS...cccccccccccccccccccncccrcccccccncenscesscccesesecese Habitat Types Designatlons..ccccccccccccccccccccccscsevens Field Methods.cccccvcccvcccvvcccsccccccvscevesveeseseseces Office PrOCedureS.ssscseceecceccecceccececenccecaeececeacs Photo Plates and Enlargements....cccccccccccccvevecces Habitat Type Boundar leS..scesseseceeccceaesccseseeees DIQITIZINGscceeecececeeeserereeccveeecccceeccresecece D&ta BASC.ccucceccccrcccvccccevevcvesccccccccvesscces Analysis ProcedureS....ccccecccccccccccccscccccrcccece RESULTS.ccc ccc cc ccc ccc ccc r ccc cre sence cece cen cee rece seesesesees DISCUSSION...cccccccccccccccecc cs ccccccccenrcccenccescccsesevce REFERENCES...ccc cc ccc ccc cece ceca cece cece reece c cence eee etseeeens APPENDICES 1 7 8 15 19 ba ay PREFACE The goal of the Alaska Power Authority In fdentifyIng environmentally acceptable fiow regimes for the proposed Susitna Hydroelectric Project Is the maintenance of existing fish resources and levels of production. This goal Is consistent with mitigation goals of the U.S.Fish and Wildlife Service and the Alaska Department of FlIsh and Game. Maintenance of naturally occurring fish populations and habitats [Is the preferred goal In agency mitigation policies. In 1982,followIng two years of baseline studies,a multi-discip!Inary approach to quantify effects of the proposed Susitna Hydroelectric Project on existing fish habitats and to identify mitigation opportunities was Initiated.The Instream Flow Relationships Studies focuses on the response of fish habitats In the middle Susitna River to Incremental changes in mainstem discharge,temperature and water qual Ity.As part of this multi-disciplinary effort,a technical report serfes was planned that would (1)describe the existing fish resources of the SusIitna River and Identify the seasonal habitat requirements of selected species,and (2)evaluate the effects of alternative project designs and operating scenarlos on physical processes which most Influence the seasonal avallability of fish habitat. The summary report for the IFRS,the Instream Flow Relationships Report (IFRR),(1)Identiffes the biologic significance of the physical processes evaluated in the technical report serles,(2)Integrates the findings of the technical report series,and (3)provides quantitative relationships and discussions regarding the Influences of Incremental changes in streamfiow,stream temperature,and water quality on fish habitats In the middle Susitna River on a seasonal basIs. The IFRR consists of two volumes.Volume |uses project reports,data and professfonal judgement available before March 1985 to identify evaluation species,important life stages,and habitats.The report ranks a varlety of physical habitat components with regard to their degree of Influence on fish habitat at different times of the year. This ranking considers the biologic requirements of the evaluation species and life stage,as well as the physical characteristics of different habitat types,under both natural and anticipated with-project conditions.Volume |!of the IFRR will address the third objective of the IFRR and provide quantitative relationships regarding the Influences of incremental changes in streamflow,stream temperature and water quality of fish habitats in the middle Susittna River on a seasonal basis. The Influence of Incremental changes in streamflow on the avallability and quality of fish habitat Is the central theme of the IFRR Volume II analysis.Project Induced changes in stream temperature and water quality are used to condition or qualify the forecasted responses of fish habitat to Instream hydraulics.The influence of streamflow on fish habitat wlll be evaluated at the microhabitat level and presented at the macrohabitat level In terms of a composite welghted usable area curve,This composite curve wil!describe the combIned response of fish habitat at ail sites within the same representative group to Incremental changes In mainstem discharge. aA AR aon a4 Four technical reports are belng prepared by E.Woody Trihey and Assoclates In support of the IFRR Volume II analysis.The function of each report is depicted In a flow diagram and described below. 1.Quantify Wetted 2.Assess the Representa-3.Determine Site Surface Area tiveness of Modeled Specific Hydraulic Response and Non-modeled Sites Conditions 4.Quantify Streamfiow Dependent Habitat 'Response Functions for Juvenile Chinook and Spawning Chum Salmon RESPONSE OF AQUATIC HABITAT SURFACE AREAS TO MAINSTEM DISCHARGE IN THE TALKEETNA-TO-DEVIL CANYON SEGMENT OF THE SUSITNA RIVER,ALASKA This report Identifies five aquatic habitat types within the middie Susitna River directly influenced by changes in mainstem discharge and presents the necessary photography and surface area measurements to quantify the change in wetted surface area associated with Incremental decreases fin malnstem discharge between 23,000 and 5,100 cfs.The report also -describes the Influence of mainstem discharge on habitat transformations and tabulates the wetted surface area responses for 172 specific areas using the ten representativegroupspresentedintheHabitatCharacterizationReport. Surface area measurements presented In this report provide a basis for extrapolating results from Intensively studied modeling sites to the remainder of the middle Susitna River. -iii- CHARACTERIZATION OF AQUATIC HABITATS IN THE TALKEETNA-TO-DEVIL CANYON SEGMENT OF THE SUSITNA RIVER,ALASKA -This report describes the characterization and classification of 172 specific areas [nto ten representativegroupsthatarehydrologically,hydraulically and morphologically similar,Emphasis fis placed on the transformation of specific areas. from one habitat type to another In response to incremental decreases in mainstem discharge from 23,000 cfs to 5,100 cfs. Both modeled and non-modeled sites are classiffed and a structural habitat index Is presented for each specific area based upon subjective evaluation of data obtained through field reconnaissance surveys.Representative groups and structural habitat Indices presented in this report provide a basis for extrapolating habitat response functions developed at modeled sites to non-modeled areas within the remainder of the river., HYDRAULIC RELATIONSHIPS AND MODEL CALIBRATION PROCEDURES AT 1984 STUDY SITES IN THE TALKEETNA-TO-DEVIL CANYON SEGMENT OF THE SUSITNA RIVER,ALASKA This report describes the Influence of site-specific hydraulic conditions on the availability of habitat for juvenile chinook and spawning chum salmon.Two aquatic habitat models are applied to quantify site-specific.habitat responses to Incremental changes In depth and velocity for both steady and spatially varied streamflow conditions.Summaries of site- specific stage-discharge and flow-discharge relationships are presented as well as a description of data reduction methods and model calibration procedures.Weighted usable area forecasts are provided for juvenile chinook at eight side channel sites and for spawning chum salmon at 14 side channel and mainstem sites.These habitat response functions provide the basis for the instream flow assessment of the middle Susitna River. RESPONSE OF JUVENILE CHINOOK AND SPAWNING CHUM SALMON HABITAT TO MAINSTEM DISCHARGE IN THE TALKEETNA-TO-DEVIL CANYON SEGMENT OF THE SUSITNA RIVER,ALASKA This report Integrates results from the surface area mapping, habitat characterization,and hydraulic modeling reports to for juvenile chinook and spawning chum salmon.Wetted surface area and weighted usable area are the principal determinants of habitat indices provided in Part A of the report for juvenile chinook at each specific area and the ten representative groups Identifled In the habitat characterization report.Part B of this report provides wadraehabitat response functions for existing chum salmon spawning sites.The habitat response functions contained [In this report will be used for an Incremental assessment of the rearing and spawning potential of the entire middie Susitna River under a wide range of natural and with-project streamf lows. -iv- meeees--4adINTRODUCTION The proposed Susitna hydroelectric project will after the natural streamflow regime of the Susitna River downstream of River Mile 232,the upstream most extent of the Watana Impoundment.The river segment upstream trom the Chulitna River confluence (Talkeetna)at River Mile 98 would experfence notable alterations in naturally occurring streamflow patterns due to its proximity to the proposed dam sites and the IImited amount of Influence that tributary inflows have on total discharge In this river segment.With-project discharges are expected to be flower than naturally occurring flows during summer and higher than naturally eccurring flows In the winter.These altered flows are expected to affect the amount and seasonal avallability of aquatic habitats. This report Identifies the location and describes the areal extent of varfous aquatic habitat types within the Talkeetna-to-Devi!Canyon segment of the Susitna River (hereafter referred to as the middle Susitna River)at different mainstem discharges.These data,In combination with the results of other studies focusingonblological aspects of aquatic habitats withIn this river segment,will facltiitate forecasting the effects of project-induced changes to natural streamflows on the availability of aquatic habitat for anadromous and resident fish. Aertal photography Interpretation,along with fleld reconnalssance,Is belng used to Identify and map varlous aquatic habitat types In the middle Sus!tna River.In 1984 initial work on aquatic habitat mapping \ and surface area measurements determined the Jocation and amount of varfous aquatic habitat types.Four sets of aerial photographs were taken at mainstem discharges of 23,000;16,000;12,500;and 9,000 cfs, as measured at the U.S.Geological Survey (USGS)Gold Creek gaging station (Klinger and Trihey 1984).These photos are discussed In this report (with the exception of the 9,000 cfs photography)together with the surface area measurements at four additional streamflows:18,000, 10,600,7,400,and 5,100 cfs.The 18,000 cfs discharge falls within the 16,000 to 23,000 cfs range,where several side sloughs and side channels become inundated by malnstem water.The lower three discharges provide a good basis for evaluating low flow conditions In the river. The surface area measurements obtained In 1984 from the 9,000 cfs photography were omitted from this report because the presence of snow and ice in the 9,000 cfs photography made It difficult to accurately determine the water's edge and measure the wetted surfaces (Klinger and Trihey 1984)(also see Discussion).The adverse influence of shorelIne Ice and snow cover on the accuracy of the 9,000 cfs data set was confirmed In a comparison between the 1984 surface area measurements obtained from.the 9,000 cfs photography and the 1985 surface area data obtained at 7,400 and 10,600 cfs (Klinger 1985). Surface area measurements for the seven discharges evaluated In this report provide an adequate basis for identifying the transformation of specific areas from one habitat type to another as a result of reductions In streamflow,as well as for quantifying the response of wetted surface area for habitat types and speclfic areas over the range of streamflows between 5,000 and 23,000 cfs.However,although wetted surface area may be used as an Indicator of habitat avallability,It a a PR does not represent habitat quality.This report,therefore,does not contain any statements concerning the suitability of the varfous habitat types for fish,nor does it contain concluslons regarding the response of habitat quality to changes in mainstem discharge. METHODS HabitatTypeDesignations The total wetted surface area of the middle Susitna River was classified Into six general aquatic habitat types:'mainstem,side channel,side slough,upland slough,tributary mouth,and tributary.These habitat types were established during ice-free conditions from physical characteristics of the environment visually evident In aerlal photography or helicopter overflights and do not necessarlly depend upon any particular degree of utilization by fish (Figure 1)._A description of the types follows. The following brief descriptions were used to Identify the s!x aquatic habitat types evaluated In this study.These definitions are limited to visually recognizable physical characteristics present during ice-free conditions that are easily Identiffed during helicopter reconnalssance flights. Mainstem habitat types are those channels of the river that normally convey streamflow throughout the entire year.They are visually recognizable by their turbid,glacial water and high velocities.In general,they convey more than 10 percent (approximate)of the total flow passing a given location. Side Channel habitat types are also characterized by turbld, glacial water.Velocities often appear lower than In malnstem sites.In general,they convey less than 10 percent (approximate) of the total flow passing a given location.Side channel habitat may exist In well-defined channels or In areas possessing numerous islands and submerged gravel bars.When the upstream berms of side channels are dewatered and the channels contain clear water,they are classified as side sloughs. Side slough habitat types contain clear water.Small tributaries, upwelling groundwater,and local surface runoff are the primary sources of clear water for these areas.Side sloughs have non- vegetated upper thalwegs that are overtopped during perfods of moderate to high mainstem discharge.When these areas are overtopped they convey turbid water and are then classified as side channels. Upland slough habitat types also contain clear water and depend on small streams,upwelitng,and local surface runoff for their water supply.Upland sloughs possess vegetated upper thalwegs that are rarely overtopped by malnstem discharge. ot bas 7 FY 4 Ed "4 i es wa4 Tributary mouth habitat types are clear water areas that exist where tributaries flow Into mainstem or side channel habitats.This habitat type is manifest as a clear water plume extending out Into the turbid receiving water.Tributary mouth habitat also extends upstream Into the tributary to the upper extent of any backwater Influence that might exist.The surface area of tributary mouth habitat Is affected both by tributary discharge and mainstem stage. Iributary habitat types are those reaches of tributary streams upstream of the tributary mouth habitats.Tributary habitat types have not been evaluated In this analysis because tributary habitat is not Influenced by mainstem discharge. Non-wetted areas were classified as either vegetated Islands or gravel bars.Areas within the control corridor that were quantified but not relevant to the surface area analysis were classified as "background." For a more detailed description of each aquatic habitat type see the Alaska Department of Fish and Game SusItna Hydro Aquatic Studies (1983). Eield Methods For the seven mainstem discharges studied In the middle SusIitna River, black-and-white aerial photographs were obtained at an approximate scale of 1 Inch =1000 feet,with a 60 percent overiap between adjacent photos.The dates of the photography and mainstem discharges as measured at the USGS Gold Creek gaging station (No.15292000)at the time of photography are presented In Table 1. Table 1.Dates and mainstem discharges at which aerlal photography of the middle Susitna River was obtalned. Date Discharge (cfs) 6-1-82 23,000 8-24-80 18,000 9-11-83 16,000 9-6-83 12,500 9-9-84 10,600 10-4-84 7,400 10-14-84 5,100 Helicopter reconnalssance flights were conducted over the middie Susitna River at mainstem discharges similar to those at which the aerial photography was obtained.During each of these reconnaissance flights, aquatic habitat types were Identifled using the key presented as Figure 1,and their locations were mapped on 1 Inch =1000 feet scale blueline prints of the Susitna River.Dewatered gravel bars and streambank areas were sketched on the blueline prints as were boundaries of the various habitat types. aaad"aaeda meres:otSsaipswane,"3mwwedweDattaatorClear Total Wetted Surface Area Total Surface Area of River Corridor on Photo Mosaics Water | Distinguishable Surface Water Source of Some Significance | | Clearwater flow not likely to be infiuenced by mainstem water surtace elevation Clearwater plume or flow likely influenced by mainstem water surtace elevation Surface area of tributary habitat Surface area of tributary mouth habitat Figure 1. | Indistinguishable or insignificant Surface Water Source Vegetated Non-vegetated upper upperthalwegthalweg Surtace Surface area of .area of upland side slough sloughhabitathabitat Key to aquatic habitat classification for the middle Susitna River (RM 101 to 149). Turbid,Glacial Water Channel conveys <10%of total flow Surface area of sidechannel habitat , Channel conveys >10%of total flow Surface area of mainstem habitat Surface Area Total Non-wetted [ Surface area vegetated islands and river corridor _| Surtace area exposed streambanks and gravel bars WW aR TY at Photo Plates and Enlargements Photographic mosaics were prepared from the overiapping black-and-white photos to provide continuous 1 Inch =1000 feet coverage for each of the seven discharges.The photo mosaics were subdivided Into elghteen sections of approximately the same length,with a small amount of overlap between adjoining river sectlons and a set of eighteen 4-1/2 Inch by 15 Inch photoplates was printed for each of the seven discharges. (Appendix 1).For the sets of photography taken at 23,000;18,000; 16,000;and 12,500 cfs,each photo plate was carefully examined and areas that were too small in size to provide detailed resolution were enlarged to a scale of 1 Inch =250 feet.Entire sets of photography taken at 10,600;7,400;and 5,100 cfs,were enlarged to a scale of1 Inch =250 feet. HabitatTypeBoundarfes Aquatic habitat boundarles mapped on blueline prints during the helicopter reconnalssance flights were transferred to corresponding sets of photographs.Figure 2 provides an example of the technique used for the photography taken at 23,000;18,000;16,000;and 12,500 cfs.The technique used for the photography taken at 10,600;7,400;and 5,100 cfs was essentially the same,with the exception that enlargement areas were not required because the entire set of photography was printed at the scale of1 Inch=250 feet.Matchlines were drawn on adjoining photo plates to ensure that habitat areas within overlapping sections near the edges of the plates were not counted twice.The boundary of each enlargement area was established using prominent topographic features In the photography and drawn on both the plate and the individual enlargement.This ensured that areas within the enlargement could be summed and compared with the enlargement area on the plate. The external boundaries of the total area to be Included in the surface area analysts (control area)were defined on each plate,so that sub- areas within the control area could be totaled and compared with the total control area of that plate.In many cases,It was necessary to go beyond the river channel boundarles to establish an [dentiftable constant control]area boundary.The area located between the control area boundary and the river channel was digitized (see below)as "background"(refer to Figure 2b). In addition to delineating habItat type boundartes,Individual channels, referred to as "specific areas,"were also delineated and digitized. This enabled the habitat type at a given location to be tracked at different mainstem discharges.Close examination of the habitat type mapping revealed that habitat type ata given location may not remain the same over a range of discharges.In general,the geographical location and persistence of certain habitat types,such as tributaries and thelr mouths,are fixed,although their surface areas may respond significantly to changes in discharge.In other cases,transformations of one habitat type Into another may occur as river stage Increases or decreases.For more detailed description of the methodology and results of the habitat transformation analysIs see AppendIx 2. wraeereaAI [LIME hg Fg AESbsSpeeFeRacecaryWeaeesat:ep ete l eSSeeaRSobpeanae ve stheHsesein AI dn, Mi A Fg Me"ee UaENEones eee ,. secrawestanat nia segs NLT ERR CDE ty Se TN TE TE 2 Be EN ieWyteQeSNC,mata BY SRO PSS,Se ey ve ag a chek tagEe SOCENE aaRVeegsiSkPatre45 ,ca :ie !S5hataWOee'=.aSeed "pe oboe:«%, tekreyomheanereeaceSx,tas ; een Ae ae *sf Ii,apne. oe mag Saeeeolggner *? a4 aywe Olgitizing In this report,digitizing refers to the process of calculating the area within a perimeter circumscribed on the aerfal photographs.Area calculations were made using a Numonics Model 2400 DigiTablet and Electronic Graphics Calculator connected to an Epson HX-20 Notebook Computer.Prior to digitizing each photo plate and enlargement, boundarjes were drawn around each wetted and non-wetted habitat element. By tracing the perimeter of a given area with the Numonics DigiTablet cursor,the area circumscribed Is calculated by the Graphics Calculator to an accuracy of 0.01 square Inch.This accuracy Is greater than that of delineation and operator tracing error. Digitizing strategy consisted of digitizing the control area,the enlargements (if any)and elements within the control area If enlargements were present,the total area of the enlargement was digitized,followed by the elements within It.Each area calculation was performed twice.If the percent error between the two measurements was greater than five percent,the area was redigitized until the percent agreement was less than five.An Interactive computer program was developed for the HX-20 which prompted the digitizing operator for the plate number,flow code,control area number,enlargement number (If any),enlargement factor,habitat code,element number,specific area river mile number,and the digitized area (transferred from the Graphics Calculator).The program checked percent agreement for each measurement and performed the summation of elements for comparison with the Initial 'control area measurement. Surface area measurements that had been stored on the Epson magnetic tape cassettes were transferred into a computerized data base for storage,sorting,and subsequent analysis.Each Individual surface area measurement was entered as a separate record that enabled Identification by discharge,photograph (corresponding to a river mile Index), Individual area number,and specific area river mile number,If appropriate. Correction factors were entered to standardize to a common scale of1 inch =1000 feet.Due to prevailing weather factors at the time of the aerial photography flights,slight variations in scale occurred in the various photo sets.Surface areas within enlargement areas and for those sets of photos printed entirely at the enlarged scale were divided by a factor of 16 to account for the fourfold difference in scale between 1 inch =250 feet and 1 inch =1000 feet, Analysis Procedures Surface areas were summed by habitat type for the entire river corridor between Talkeetna and Devil Canyon for each of the seven discharges. Percentages of the total river surface area represented by each aquatic habitat type were calculated.Surface areas of Individual channels (specific areas)were also determined. ay Ty BY Localized changes In channel geometry which occurred as a result of high flow events in 1981 (Klinger-Kingsley and Trihey 1985)resulted in some inconsistent surface area measurements for the 18,000 cfs photography. 'These Inconsistencles were considered an artifact of using photography obtained before and after a major flood event.The 18,000 cfs photography Is the only pre-1981 condition analyzed,whereas post-1981 conditions are represented.by six sets of photography with flows.ranging from 5,100 to 23,000 cfs. Because the change In surface area of aquatic habitat is a function of discharge and channel geometry,the middie Susitna River was subdivided Into four subsegments,each possessing somewhat different geomorphological characteristics.RM 101 to 113 (Talkeetna-to-Lane Creek)is a relatively channelized subsegment of the middie river with few mid-channel vegetated Islands or gravel bars and few side channels branching off from the mainstem.RM 113 to 122 (Lane Creek-to-Curry)Is a more braided subsegment with mid-channel islands and side channels branching from the mainstem.RM 122 to 138 (Curry-to-Gold Creek)Is a bralded subsegment with large mid-channel Islands and gravel bars and numerous side channels branching off from the mainstem.RM 138 to 149 (Gold Creek-to-Devil Canyon)Is a more channelized subsegment with some large slde channels branching off from the mainstem.Total surface areas of each habitat type within these subsegments were determined to focus attention on the diversity of habitat types and surface area responses among subsegments with different morphologic characteristics. The percent change In habitat type surface area between that present at 23,000 cfs and at the other discharges of Interest was calculated. Average monthly discharges for the Susitna River at Gold Creek range from 1,500 cfs In winter to 28,000 cfs during summer with an average annual discharge of 9,700 cfs (Figure 3a).Snowmelt runoff during June and early July accompanied by glacial melt and rainfall runoff during July and August provide stable and persistent high summer discharges (Figure 3b,c,d).From an analysis of the hydrologic data,it was determined that the aerfal photography obtained at a mainstem discharge of 23,000 cfs represents a typical mid-summer discharge for the middle SusItna River.Therefore,this photography was used to depict baseline mid-summer conditions. RESULTS Total surface areas for aquatic habitat types In the middle Susitna River are presented in Table 2.In some cases,such as for tributaries and thelr mouths,habitat type Is associated with specific geographical location and the habitat type persists over a broad range of streamflows -even though the surface areas may respond significantly to changes In discharge.In other instances,specific geographic locations transform from one habitat type Into another as river stage Increases or. decreases. AY ay mn ms wadwrenDischarge(cfs)A.B. 30,000 108 8 6 4 " 25,090 + Pd 2 ee Average Monthly --»10820,000 -8a7}6 @ 42 15,000 s 3 2 a A e Annual 10? vera10,000-4_"verageoneSe 8 4 5,000 2 JUNE 102 14 0 10 20 30 40 50 60 70 80 90 100 1 54 T %of Time Discharge Equalled or Exceeded ON DJS FMANMJ J A S Months Cc..OD. 5 10538 6 6 44- 10410¢ 8 8 2 2S6ky 6 e 4 2 4 «a£=So 2 $2 ra a 3 10338 6 6 4 4 2 2 JULY AUGUST 102 jt 102 tk 0 10 20 30 40 50 60 70 80 90 100 0 10 20 30 40 50 60 70 80 90 100 %of Time Discharge Equalled or Exceeded %of Time Discharge Equalled or Exceeded Figure 3.Average annual discharge and average monthly dischargesfortheSusItnaRiveratGoldCreek(adapted from Scully,Leveen,and George 1978);b,c,d.Monthly flow durationcurvesfortheSusitnaRiveratGoldCreek(adapted from Acres American Inc.1983). Surface area values presented in Table 2 were plotted to [Illustrate the surface area responses of Individual habitat types in response to changes in malnstem discharge (Figure 4).Surface areas of mainstem and side channel habitats were smaller at lower discharges.Concurrently, exposed gravel bar surface areas were larger at lower discharges. Side slough surface area Increased with decreasing discharge down to a malnstem discharge of 7,400 cfs,and then decreased at 5,100 cfs. Upland slough surface area remalned relatively constant over the range of mainstem discharges,decreasing somewhat at 5,100 cfs.Surface area of tributary mouth habitat was largest at Intermediate flows of 16,000 and 12,500 cfs.Vegetated bar surface area remained relatively constant over the range of mainstem discharges. Examination of the data reveals Inconsistent surface area measurements for side channel and side slough habitat types for the 18,000 cfs photography.Side channel surface area Is lower and side slough surface area Is higher than values expected from Interpolation between data points at 16,000 and 25,000 cfs.Examination of flow records for the middie Susitna River reveal that July and August 1981 were periods of relatively continuous high flow events (KI inger-KIingsley and Trihey 1985).In addition,comparison of stage-discharge relationships prepared before and after July-August 1981 shows a 0.25 ft.reduction In stage for equivalent discharges (USGS 1972,1982).This suggests that scouring occurred during the high flow events of 1981.This Is consistent with the observation of less side slough and more side channel habitat surface area measured on post-1981 photography.As channels were scoured,lower mainstem discharges would be required to AY wh aE 2 overtop the head berms,resulting in more sIde channel surface area and less side slough surface area at a given discharge after 1981 than prior to 1981. Table 3 presents the percentage of the total river corridor represented by each habitat type for each of the seven mainstem discharges.Table 4 presents the percent change In the surface area of each habitat type at each discharge as calculated from a baseline discharge of 23,000 cfs. The middle Susitna River was divided Into four subsegments based upon differing geomorphological characteristics.These subsegments extend from approximately river miles (RM)101 to 113,113 to 122,122 to 138, and 138 to 149.Because of differences In the amount of surface area within each river subsegment and the desire to accent the response of habitat surface areas within the river subsegments,surface areas for the varltous habitat types are reported as the percentof total area In the subsegment river corridor (Figure 5).Figure 6 presents a relative comparison of total surface areas calculated for varlous habitat types within the entire Talkeetna-to-DevI|Canyon segment and within the four subsegments In response to changing malnstem discharge. -10- fe 7 7 44 a3 a 7 Bxa?a zy " Table 2.Total surface areas by habitat type within the middie Susitna River. Habitat Type 2,100 cfs 1,400 cfs 10,600 cfs 12,500 cfs 16,000 cfs 18,000 cfs 23,000 cts Mainstem Stde Channel Stde Slough Upland Slough Tributary Mouth Gravel Bar Vegetated Bar 2453.0 768 .2 118.8 16.4 15.6 2522 .9 1958.5 2595.1 854.0 145.6 20.8 15.5 2299.6 2140.3 surface Area (acres)byDischarge 2789 .8 982 .9 134.8 21.5 18 .6 1852.4 2079 .3 2850.4 1095.5 118.1 22.0 26.2 . 1727.7 1919.1 3158.5 1222.2 85.8 22.6 25.3 1419.2 2011.4 3316.0 952.0 116.1 24.6 18.4 1249.4 1985.2. 3737.2 1240.7 52.5 24.4 12.1 815.8 1718.4 -l1- §000 1000 500 SurfaceArea(acres)100 50 10 Figure 4. MAINSTEM 7 GRAVEL BAR 4 SIDE CHANNEL °4 °o .SIDE SLOUGH q Le Sao TRIBUTARY MOUTH 1 1 4 op f yy y gg yy -45 y¥5 5 |YF 4g 4 -3MainstemDischargeatGoldCreek(x10 cfs) Surface area responses to mainstem discharge In the "middie Susitna River (RM 101 to 149). Table 3.Surface areas by habitat type within the middie Susitna River Table 4,Percent change In digitlzed surface areas relative to expressed as a percentage of the total river corridor area.corresponding areas present at 23,000 cfs. Percentage by Discharge .PercentageChangebyDischarge Habitat Type 2.100 cfs 21400 cfs 10,600 cfs 12,500 cfs 16,000 cfs 18,000 cfs 25,000 cfs Hab ltat Type 18,000 cfs 16,000 cfs 12,500 cfs 10,600 cfs 1.400 cfs 5,100 cfs cay Malinstem 31.2 32.2 35.1 36.7 39.7 43.3 49.1 Malnstem -11.3 -15.5 -23.7 -25.4 -30.6 -34.4 Side Channel 9.8 10.6 12.5 14.1 15.4 12.4 16.3 Side Channel -23 3 -1.5 "11.7 -20.8 -31.2 38.1 Side Slough 1.5 1.8 1.7 1.5 1.1 1.5 0.7 Stde Slough 121.1 62.8 124.1 155.8 176.3 125.4 Uptand Stough 0.2 0.3 0.2 0.3 0.3 0.3 0.3 Uptand Slough 0.8 -7.4 -9.8 -11.9 -14.8 -32.8 Tributary Mouth 0.2 0.2 0.2 0.3 0.3 0.2 0.2 Tributary Mouth 52.1 109.1 116.5 53.7 28.1 28.9 Gravel Bar 32.1 28.5 23.5 22.2 17.9 16.3 10.7 Gravel Bar 53.2 74.0 111.8 127.1 181.9 209.3 Vegetated Bar 24.9 26.5 26.4 24.7 25.3 25.9 22.6 -12- xnaa Figure 5.PercentTotalRiverCorridorSurfaceAreaPercentTotalRiverCorridorSurfaceAreaTalkeetna-to-Lane Creek RM 101 to 113 TY T T ¥TTF tT T T T TvTTqq T 60f- MAINSTEM 40r 4 30+GRAVEL BAR 4 20 t-4 SIDE CHANNEL 10F SIDE SLOUGH la i i A I 4 T -a {ote re rm {de he 10 15 20 +3MainstemDischargeatGoldCreek(x10 cfs) _Lane Creek-to-Curry RM 113 to 122 tT v 7 Li v qT v v TT v J v v OT v ]Lom |1 60 ' 4 Sor MAINSTEM 30 GRAVEL BAR 20 1k SIDE CHANNEL? SIDE SLOUGH Seer Ge GE Gy Oar ae Gas ee ee we ee ee 5 10 15 20 -3MainstemDischargeatGoldCreek(x10 cfs) Surface area responses to malnstem discharge expressed as a percentage of the total river corridor surface area within each of four river subsegments. 13-PercentTotalRiverCorridorSurfaceAreaPercentTotalRiverCorridorSurfaceArea60 50 40 30 20 Curry-to-Gold Creek RM 122 to 138 - Teer Tyr rrr Tr rr ry rr. MAINSTEM GRAVEL BAR SIDE CHANNEL 10 f-ae SIDE SLOUGH . a as a bo a kt a gk dt dt CUOY 5 10 15 20 .:-3MainstemDischargeatGoldCreek(x10 cfs) Gold Creek-to-Devil Canyon RM 138 to 149 T vT Y T TT ¥v YF T ]y TT T FT q Tr ¢v 60 }-4 sol MAINSTEM 40+4 30 4 GRAVEL BAR 20--4 SIDE CHANNEL 10 --com SIDE SLOUGH abs et ft ok +-+ra area 5 10 15 20 -3MainstemDischargeatGoldCreek(x10 cfs) wy RY 3 BY ce 'taie Discharge (cfs) Talkeetna to Devil Canyon RM 101 to 149 Talkeetna to Lane Creek RM 101 to 113 Uj;Mainstem Side Channel Lane Creek to Curry Side Slough RM 113 to 122 Gravel Bar peace]Vegetated Bar Curry to Gold Creek RM 122 to 138 Gold Creek to Devil Canyon RM 138 to 149 Figure 6.A comparison of relative amounts of the different habitat types comprising various subsegments of the Susitna River at seven mainstem discharges. -14- oso Be|ce ey Y DISCUSSION Air photo interpretation Is highly dependent upon the quality of the photography. was generally clear and complete,the time of day,date,and prevailing weather conditions at the time the aerial photographic missions were flown affected the extent to which detailed riverine features were visible. The 23,000 cfs photography,taken on June 1,1982,was obtalined at a time of the year when the sun was at a high angle and decidfous vegetation had not fully leafed-out.This resulted in few shadows, enabling excellent delineation of water's edge and slough boundaries. The 7,400 cfs and 5,100 cfs photography,obtained on October 4 and 14, 1984,respectively,have extensive areas of shadows along the south and east shorelines.This was due primarily to the low sun angle during that time of year.These shadows sometimes obscured the water's edge and made some sur face area del ineations more difficult.The remaining sets of photography had isolated shadow problems.In spite of the minora problems with photographic detail,accurate and rellable surface area measurements were obtained using varfous techniques to aid in del Ineations. The 9,000 cfs photography,taken on October 8,19835,was suspected of providing somewhat erroneous surface area measurements:because of prevalling snow and river [ce conditions.Mainstem and side channel surface area measurements obtained from the 9,000 cfs photography underestimated total surface area because of the Influenceof shore ice Although each set of photographs obtained for this study -15- which reduced wetted top width.Side slough habitat at 9,000 cfs was overestimated [in 19835 because the sharp contrast between snow and wet sand made it extremely difficult to accurately define the water's edge. Tributary mouth habitat was underestImated In 1983 because of the difficulty in distinguishing between the clearwater plume of the tributary and the clearing mainstem.Because of these problems with the 9,000 cfs photography and the discrepancies in the surface area data when compared to the 10,600 and 7,400 cfs data,the 9,000 cfs photography and data were not included In this analysis. Aquatic habitat surface area responses are a function of streamflow and channel geometry.Localized channel geometry changes were observed between the 18,000 cfs photography obtained in 1980 and the remaining six sets of photography taken in 1982-84 (Kl iInger-Kingsley and Trihey 1985).These appeared to have been the result of high flow events which occurred during July and August 1981.The apparently inconsistent surface area measurements for side channel and side slough habitat types at 18,000 cfs can be explained as a result of scouring which occurred during this period. Closer examination of the 18,000 cfs data shows a difference of approximately +40 acres between the amount of side slough surface area present on the 18,000 cfs photos versus the amount expected by interpolation between 16,000 and 23,000 cfs.Conversely,a difference of approximately -280 acres Is apparent between observed and expected surface area values for side channel habitat at 18,000 cfs.The scouring out of channels could be expected to have resulted in hablitat transformations from side slough to side channels at locations where ER aS a a head berms were lowered.These transformations could account for the 40 acres of side slough surface area apparently lost.The additional 240 acres of side channel surface area beyond that gained due to habitat transformation from side slough may be aresultof lateral cutting of the banks of the channels.This lateral cutting would result In a wider channel and,therefore,a greater surface area for a given length of channel. Channel mor phol ogy changes and habitat transformations are considered a normal occurrence when viewed In the context of long term channel behavior.Studies conducted on braided glacial rivers in New Zealand (Mosley 1982,1983)Indicate that multi-channel river systems typical ly provide arelatively constant amount of habitat despite the frequent morphological changes the river experfences. The channel changes and accompanying habitat transformations represent a relatively small percentage of the total wetted surface area of the middle Susitna River.At 23,000 cfs,approximately 5,000 acres of wetted area Is present.The 40 acres of side slough habitat which was transformed into side channel habitat represents0.8 percentof that total wetted area.The additional side channel habitat galned as a result of lateral channel bank cutting or other similar processes represents approximately 4.8 percent of the total wetted surface area. The magnitude of channel changes expected to occur during years exhibiting more typical flow regimes would be expected to be less than these. -16- Definitions for aquatic habitat types used In thIis study represent a set of visually recognizable,environmental characteristics that do not restrict the occurrence of a particular habitat type to fixed geographicat locations.An example of the flow-dependent nature of these definitions and how habitat transformations may occur is reflected by side slough and side channel habitats.SIde sloughs,by definition, are clear water habitats In which the flow Is malntalned by upwelling and local surface runoff.A non-vegetated alluvial berm at the upstream end of the dewatered overflow channel separates the clear water habitat 'from the active channel.When mainstem discharge Increases and river stage rises,the alluvial berm at the head of the slough is overtopped. Turbid mainstem water flows Into the channel and replaces the former clear water habitat with deeper,faster-flowing turbid water.The aquatic habitat at this location then fits the definitlon of side channel habitat.Conversely,as malnstem discharge decreases,areas classified as side channels may become cut off from mainstem flow at thelr upstream end and become clear water habitats.If the clear water inflow to these systems is sufficient to maintain a downstream connection with the mainstem,these areas fit the definition of side slough habitat. General trends In surface area response to mainstem discharge became apparent In this study.As mainstem discharge decreased,the surface area of both mainstem and side channel habitat types decreased. Concurrently,side slough habitat surface area Increased with decreasing discharge.The decrease In side slough surface area shown at 5,100 cfs aS 8 33 wR..|was due to some of the sloughs dewatering at their downstream end leaving remnant,ponded water which was not considered available habitat. The surface area response of mainstem,side channel,and side slough habitats Is not necessarily directly correlated with habitat quality, nor does it directly reflect the amount of usable habitat available. For example,In mainstem and some side channel habitats,velocity and depth may be IImiting factors for the distribution of fish.As mainstem and side channel surface areas decrease with decreasing mainstem stage, water depths and velocities In these areas are reduced,possibly making these habitats more suitable for use by fish.Cenversely,as mainstem discharge decreases and side slough habitat surface area increases, these already shallow slough areas may become even shallower with very low velocities.Access Into these areas may become a problem and/or the shallow depths of the sloughs themselves may resuit In less than sultable habitat. Trends In surface area response for tributary mouth habitat were such that surface area was lowest at a mainstem discharge of 23,000 cfs, highest at moderate mainstem discharges and decreased at discharges of 10,600 cfs and below.At 23,000 cfs,the combination of high mainstem stage and water velocities resulted In a shearing off of the clear water plume as it entered the mainstem,Tributary mouth habitat surface area is a function of both mainstem discharge and tributary flow.The decrease In tributary mouth surface area at the lower mainstem discharges probably reflects lower tributary flows.The 5,100 and 7,400 cfs photos were taken In October when tributary flows are very low. -17- Upland slough surface area remained relatively constant over the range of malnstem discharges Investigated.At 5,100 cfs,the low surface area was due to some upland sloughs becoming dewatered at thelr mouths leaving the sloughs as remnant,ponded areas [naccessible to fish. At lower mainstem discharges,the combined surface area of clear water habitats was greater than at higher mainstem discharges.For example,a reduction in malnstem discharge from 25,000 to 10,600 cfs (essentially halving the mid-summer flow)results In a 200 percent Increase In total clear water surface area with a 50 percent decrease in turbid water surface area,and a 125 percent increase In exposed gravel bars.Even a decrease In discharge from 23,000 to 16,000 cfs results in a 170 percent increase In clear water,primarily due to Increased tributary mouth surface area.This Increase In clear water may be Important for primary and secondary production if these clear water areas remain relatively stable. it must be re emphasized here that an increase In clear water surface area Is not directly correlated with an Increase In suitable fish habitat.Upwelling and intragravel flow have been recognized as strongly influencing the spawning behavior of chum and sockeye salmon In Alaska (Estes and Vincent-Lang 1984).By definition,side sloughs are clear water areas maintained by upwelling.Without field verification, it is difficult to distinguish between true side sloughs and areas containing clear water due to settling out of suspended sediments and possibly dilution by surface water runoff once the upstream berm of a side channel Is dewatered. ey nh ay BB coe a3 Different subsegments of the middle Susitna River have different morphology and vary In the relative amounts of wetted areas,gravel bars,and vegetated Islands.In all subsegments,mainstem and vegetated island surface areas predominate.The greatest diversity occurs In the Lane Creek-to-Gold Creek subsegment (RM 113 to 138),In which a greater percentage of the total surface area Is represented by grave!and vegetated bars.This river subsegment Is characterized by.a more braided channel pattern.In these areas,the relatively large edge effect due to the numerous [slands and gravel bars may result In the greatest potential for creation of more usable habitat along channel margins and In channels with higher streambed elevations as mainstem stage drops and water velocities are reduced.In contrast,the relatively steep-banked,channelized areas of the river where edge effects are minimal,such as from RM 102 to 115,will probably not show as large an increase In potential habitat. The results of this study can be used to IndIcate the potential for increase or decrease In the amount of usable habitat by evaluating surface area responses of various habitat types during the open water season and with existing channel geometry.The term usable habitat would Include not only fish habitat,but also aquatic habitats suitable for primary and secondary production.However,the limitations of the surface area data generated by this study must be realized.These limitations reflect the strictly physical descriptions of the habitat types defined here. -18- The results of this study,however,can be applied to both ongoing and future studies which focus more directly on various blological features of aquatic habitats.Habitat reconnaissance work done by Aaserude,et al.(1985)focused on further defining and subdividing habItat types Into categories which more specifically define habitat attributes and responses to flow.Fish utilization data (Hoffman 1985)will be appl led to the results of the habitat reconnalssance work to provide a measure of the suitability of the varlous aquatic habitats for use by adult and juvenile salmon. Measurements of primary production in the middie river are anticipated from AEIDC.This work,in combination with the development of a euphotic surface area response model (Reub,et al.1985),wlll address the issue of with-project primary production potential.These studles will provide biological significance to the increase In total surface area of clear water habitats seen In this study as mainstem discharge decreased, es agean arya v REFERENCES Aaserude,RJ.,J.Thiele,and D.Trudgen.1985.Categorization and characterization of aquatic habitat types of the middie Susitna River.E.Woody Trihey and Assoclates.Anchorage,AK.Technical memorandum.1 vol. Acres American Inc.1983.Susitna hydroelectric project FERC license application,Exhibit€,Chapter 2,Anchorage,AK. Alaska Department of Fish and Game,Susitna Hydro Aquatic Studies.1983. Phase I!basic data report.Vol.4:Aquatic habitat and instream flow studies,1982.Anchorage,AK.Part 1,p.2. Bredthauer,S.,andB.Drage.1982.Alaska Power Authority,Susitna hydroelectric project;task 3 -hydrology;river morphology.R&M Consultants,Inc.,Anchorage,AK.Report for Acres American Inc. Estes,C.C.,and D.S.Vincent-Lang,eds.1984.Report No.3.Aquatic habitat and instream:flow Investigations (May-October 1983). Chapter 7:An evaluation of chum and sockeye salmon spawning habitat In sloughs and side channels of the middle Susitna River. Susitna Hydro Aquatic Studies,Alaska Dept.of Fish and Game. Report for Alaska Power Authority,Anchorage,AK.Document 1936. 1 vol. Hoffman,A.G.1985.Report No.9.Summary of salmon fishery data for selected middie Susitna River sites.Susitna Hydro Aquatic Studies,Alaska Dept.of Fish and Game.Report for Alaska Power Authority,Anchorage,AK.1 vol. Klinger,S.1985.Analysis of middle Susitna River aerlal photography and determination of aquatic habitat type surface areas.E Woody Trihey and Associates.Anchorage,AK.Technical memorandum.6 pp. -{9- Klinger,S.,and W.Trihey.1984.Response of aquatic habitat surface areas to mainstem discharge in the Talkeetna-to-Devil Canyon reach of the Susitna River,Alaska.E.Woody Trihey and Associates, Report for Alaska Power Authority.Susitna Hydroelectric Project. Document 1693.1 vol. Kl inger-Kingsley,S.A.,and E.W.Trihey.1985.Reconcil tation of. surface area measurements In the 1980 and 1984 aerlal photography of the middie Susitna River resulting from localized changes in channel morphology.&Woody Trihey &Associates.Anchorage,AK. Technical memorandum.1 vol. Mosley,MAP.1982.Analysis of the effect of changing discharge onchannelmorphologyandInstreamusesInabraidedriver,Ohau River New Zealand.Water Resources Research 18(4):800-812. ” _____.-1983.Response of braided rivers to changing discharge.Journal of Hydrology 22:(1)18-67. Reub,G.,E.W.Trihey,and C.Wilkinson.1985.Preliminary analysts of the Influence of altered middle river discharge and turbidity "regimes on the surface area of the euphotic zone.E.Woody Trihey and Assoclates.Anchorage,AK.Technical memorandum.1 vol. Scully,D.R.,L.S.Leveen,and R.S.George.1978.Surface water records of Cook Inlet Basin,Alaska,through September 1975.U.S. Geological Survey,Anchorage,AK.Open-flle Report 78-498.102 pp. Steward Ill,C.R.,RC.Wilkinson,and A.Milner.1985.Response of juvenile chinook habitat to malnstem discharge In the Talkeetna-to- Devil Canyon segment of the Susitna River,Alaska.Trihey and Associates.Report for Alaska Power Authority,Anchorage,AK.1 vol. University of Alaska-Falrbanks,Arctic Environmental Information and U.S. U.S. Data Center.1985.Geomorphic change in the middle SusIitna River since 1949.Report for Alaska Power Authority.Susitna Hydroelectric Project.53 pp. Geological Survey.1972.Rating table for SusItna River at Gold Creek,Alaska from October 1,1967 to 1972.Unpublished data. Geological Survey.1982.Rating table for SusItna River at Gold Creek,Alaska from October 1,1981 to 1982.Unpublished data. -20- aweAppendix 1.Aerial photographs of the middle SusItna River.Aquatic habitat7B'2é types are delineated at seven mainstem discharges.Prominent topographic features and study sites are identified. _-sy f ca Appendix 1.Aerfal photographs of the middie Susitna River.Aquatic habitat types are del[neated at seven mainstem discharges.Prominent topographic features and study sites are Identified. oe e NEB hsolFSDaa # IG AFreps gs ES=kNES ete Sereraiin ead aE BARE BASCO&i ] SUSITNA JOINT VENTURE HARZA Aquatic Resource Associates Specaists Trihey & ALASKA POWER AUTHORITY SUSITNA HYDROELECTRIC PROJECT RIVERMILE 147 TO 149 5000 cfs MIDDLE SUSITNA RIVER 23 PLATE 1 OF 18 RIVER MILE TM TRIBUTARY MOUTH TRIBUTARYT + MS MAINSTEM SC SIDE CHANNEL SS SIDE SLOUGH US UPLAND SLOUGH LEGEND SSanero we angoy aA ”aynry&weTeeOe,43sf4+atept ;aaa S,5 2IeCESSTeeraantReetanester§ ggg YS oe8 ORLA ;Shikne.ey f ee hk <sas ae .SERRE TAICC hn 2ee £¢0 SO ESE ge hasSeitnangEleBOOeBeaSPEaSICALSGORECATHSEY"he GERI hoe Se asc at gE FRE ois Oe See 16:y 'SPE Bt om : ;PLY,oe Pihege BRE ee AE aot fhe 8eyccs3BESyROMYGISAtes We ape :Spee Ge 4 ae f Pyea Pax ee eh z ite ais ”See t Me ie#3 neh Oe eee)ak pe¥hyeMyMeOHVai tatesMeBoeae 3 rns,ms enr pseton$=;ah:Pac weaeSalarAc? ey lag DnRata .a +.if é e 2 je 9 ”hag'ed ve £ae:FBS GAE Apit OERTBaUEaIebBSSS, LEGEND IDDLE ) MS MAINSTEM ™TRIBUTARY MOUTH M SUSITNA RIVER sc SIDE CHANNEL T TRIBUTARY SS SIDE SLOUGH +RIVER MILE PLATE 1 OF 18 RIVERMILE 147 To 149 Ss)Associates HARZAEBASCO ALASKA POWER AUTHORITY SUSITNA HYDROELECTRIC PROJECT US UPLAND SLOUGH SUSITNA JOINT VENTURE i €3 ne 2 5 )y .oh a i APIS 3 Si ¥ LEGEND MS MAINSTEM SC SIDE CHANNEL SS SIDE SLOUGH US UPLAND SLOUGH TM TRIBUTARY MOUTH T + TRIBUTARY RIVER MILE MIDDLE SUSITNA RIVER PLATE 1 OF 18 RIVERMILE 147TO 149 a Paes HecRee=ERE oN ites ay eeSeoe CARuyyeanigteSPALS:4*aSy:wh pane oe Le ALASKA POWER AUTHORITY SUSITNA HYDROELECTRIC PROJECT Trihey &Associates Aquatrc Resource Specaists HARZA-*EBASCO SUSITNA JOINT VENTURE = neeell7aawdwaweeare]wi83=-_-!i4SK A ne TELM ASS ROO gett 7 FORA EE BI SyO 357 SE ETET:any Pt YER ¥nat ae Ssen Ser ee REE2fon'c Ae 'aN Me 3!rs Lad heey,Re fae rs ,. eal Shade Rare wer oo Re Tei:Cae Wet AS age SS é %erCROSSoF"we"ayNerePagalre.PY TAR ER,os HH POR FLEES tT'vi RE ENE ce OM ae ee anfd PLRFerx;ufanei, . "ome fF ra )3 3 ye my ;Dg.”es 4 :MATE f, -a . st >,as ase pat gene a ie >:cara a % PORTAGE creeiye SBF,LEGEND ALASKA POWER AUTHORITY MS MAINSTEM IM TRIBUTARY MOUTH |-MIDDLE SUSITNA RIVER SUSITNA HYDROELECTRIC PROJECT SC SIDE CHANNEL T TRIBUTARY eh tue mmpen SS SIDE SLOUGH +RIVER MILE PLATE 1 OF 18 RIVERMILE 147 To 149 hasehntes HARZAet AEEO US UPLAND SLOUGH Saat Pesoree TP SUSITNA JOINT VENTURE eo ia AR NES,Yerees4 fee 7 OEE ieeeA . x eee ec eaoeSaesce eeoe eyaeismaSiehsie[sg NeeLONGCR weePERE ALASKA POWER AUTHORITY SUSITNA HYDROELECTRIC PROJECT HARZA>EBASEO SUSITNA JOINT VENTURE AssociatesTrihey& Aquatic Resource Specaists MIDDLE SUSITNA RIVER PLATE 2 OF 18 RIVERMILE 144 To 146 000 cfs23, LEGEND TA TRIBUTARY MOUTHMSMAINSTEM TRIBUTARY RIVER MILE TSCSIDECHANNEL SS SIDE SLOUGH + US UPLAND SLOUGH araeLEGEND MS MAINSTEM TM TRIBUTARY MOUTH SC SIDE CHANNEL T TRIBUTARY SS SIDE SLOUGH +RIVER MILE US UPLAND SLOUGH ; SE ETE MayeeCOS *)J Mey ;ee 3 SE ovatAatve fda ts 2 ead pee Bing! 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ALASKA POWER AUTHORITY__MIDDLE SUSITNA RIVER SUSITNA HYOROELECTRIMSMAINSTEMTMTRIBUTARYMOUTH;CTRIC PROJECT |SC SIDE CHANNEL T TRIBUTARY Trihey &HARZA*EBASECOSSSIDESLOUGH+RIVER MILE Associates , US UPLAND SLOUGH PLATE 15 OF 18 RIVERMILE 108 TO 110 Se ete'|SUSITNA JOINT VENTURE Se Pier ARTGOO BYE! Kons $a Tg Sie iia i ke ik Ke13k: * o $m Mie PT OR EIATe fF SBT Zoe had jhe .<z) a”,5 LEGEND ALASKA POWER AUTHORITY MS MAINSTEM TM TRIBUTARY MOUTH MIDDLE SUSITNA RIVER SUSITNA HYDROELECTRIC PROJECT ee SIDE sLouGH .'RIVER MILE PLATE 15 OF 18 RIVERMILE 108 To 110 hevctites |WARZA*EZBASCO US UPLAND SLOUGH . Seew |SUSITNA JOINT VENTURE BokstaSeRPA naSS at aytagnety SRN ALAGAa om,in1pLstar aeeeae é MEE E DT EES D0 ES, a Ct al e 4 = u ¥,soe rs ef.Pe pedalCog cice 2 Weoanes 1 Ca oéBEEeyoatotLoeee SiteAlge erat ereNTES:Rd!%RNPce Oat oe1S pa aes am Ye ye Tt IOS,:Se Geer a Span.Ss theSUEAne!Fue te ee EE 55BemePaeeionae, é,et.Se e'sesa)&Beane LEGEND ALASKA POWER AUTHORITY MS MAINSTEM TM TRIBUTARY MOUTH MIDDLE SUSITNA RIVER SUSITNA HYDROELECTRIC PROJECT SC SIDE CHANNEL T TRIBUTARY PLATE 16 OF 18 RIVERMILE 105 To 107 Trihey &. SS SIDE SLOUGH +RIVER MILE Associates _HARZA-RBASCOUSUPLANDSLOUGH23,000 cfs Cewe'|SUSITNA JOINT VENTURE zy ry Anes_s3-A-_sa4 terete aeeyBENREPOASteeSeay? pepe es" oe G «s i oy.oh,geet oseaeanfBeyoer"Serene Ou em tag OEE a) 5 NN By%. Pe,at Mee AS sf oFSt."=Sake Fe i ah LF teak,Re te =ry Sat iS ares to Se:=; :ve ;-¥.rex, 4 rae 4 Roe -s»bh }ERTL p ey : Pe 6 2 deel Be ieee \.4 4 coat 3e . ?o ;#1 ¥nod ay .ot Lig tk a Ad rtintebeosRELASSESORREETwhet PRES AITA PSSST TS ty kN rR aresPUENTEhETRHeReb=Fhe+,:' .¢St.&3 a4oy:e* Pee a eSrytaaTE ;i 2 fi ited aa .Rs di,:.::Ae he et?S.a ee Sat POE RLS Fe OR Pee EEEES Ralf gS PpRASSne:-ee aN ACRE Vera BRAK 2 2 BS Lag teats ent.=*"tre Qa OPTRA SLL eet > LEGEND MS MAINSTEM TM TRIBUTARY MOUTH SC SIDE CHANNEL T TRIBUTARY Trihey &. SS SIDE SLOUGH +RIVER MILE PLATE 16 OF 18 RIVERMILE 105 TO 107 Associates HARZARBASCO US UPLAND SLOUGH Soocass«|SUSITNA JOINT VENTURE ALASKA POWER AUTHORITY MIDDLE SUSITNA RIVER SUSITNA HYDROELECTRIC PROJECT B i DYNES OTe agW Bact phe LEGEND MS MAINSTEM T™TRIBUTARY MOUTH SC SIDE CHANNEL T TRIBUTARY SS SIDE SLOUGH +RIVER MILE US UPLAND SLOUGH BS SOSEero 2 PyP Reh Pp)Ss 4 4 wee ? 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MIDDLE SUSITNA RIVER PLATE 16 OF 18 RIVERMILE 105 To 107 ALASKA POWER AUTHORITY SUSITNA HYDROELECTRIC PROJECT Tri &fasetiates HARZA*RBASCO Aquatic ResourSpeaaiss«|SUSITNA JOINT VENTURE MRRIA SI 2 :at net esa rire ee,ees as LEO EN TH qari PAR Ee:zae,a vr Ay &eve Ad Ny >.eit Ae ld LER GT a5 bop Fg:lege,2 LVS Z ya > Chg thy 4 fee aE ge Oe NNweedyfsSapisHatiesFon40)PAT See A:fia ogee "a ee ee en he ees ba REGaNe)ET BESS SRELUNhoet=")¥ aoe .7 SOE ae\oF: Pa 27ReeaaeinOOSt,Sgt Pay PateG ety <7Pesctr. ioe na he wr}eema.SF LEGEND MIDDLE SUSITN ALASKA POWER AUTHORITY AR MS MAINSTEM TM TRIBUTARY MOUTH IVER SUSITNA HYDROELECTRIC PROJECT SC SIDECHANNEL 7 TRIBUTARY eye ; SS SIDE SLOUGH +RIVER MILE PLATE 16 OF 18 RIVERMILE 105 To 107 Associates _HARZA EBASCOUSUPLANDSLOUGHSees|SUSITNA JOINT VENTURE rh i” 57 ae 4,® " ¥ 4?St SoeiconeoRes 'het¢ * a# att,ren? 7)cZ,Lyys Paes " *hate OA Ras Wee ae BSTEUStancelerooea LEGEND MS sc Ss US MAINSTEM SIDE CHANNEL SIDE SLOUGH UPLAND SLOUGH T TRIBUTARY MOUTH T + TRIBUTARY RIVER MILE ant 4, a aes 6 PI TAT EY a tate es teaAS tb TI(ansPs Boe,"3 Qty eeRy™.,Nahe! 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Ftae Se,BaK,NSxa apra Oe& <”oe, er,Aahya 2,oH 2" snaS Sideimety%<a+ ae fon «Se a peekSedanceeeBEESBee ALASKA POWER AUTHORITY SUSITNA HYDROELECTRIC PROJECT ey TARZA SBASCO SUSITNA JOINT VENTUREAquaticResource Speaaists AssociatesTrihey& MIDDLE SUSITNA RIVER PLATE 18 OF 18 RIVERMILE 101 TO 102 000 cfs23 LEGEND TM TRIBUTARY MOUTHMSMAINSTEM TRIBUTARY RIVER MILE T + SC SIDE CHANNEL SS SIDE SLOUGH US UPLAND SLOUGH ,eee ®arEUWMANOot heieee ae .ay setg ty y v2 ea:aan ;het DEUS B98 RASS Elis,ty ea EES sere AOD TR TM 3 M "LS,AOS pre rere: 3 ny De».é LEGEND ALASKA POWER AUTHORITY MS MAINSTEM TM TRIBUTARY MOUTH MIDDLE SUSITNA RIVER SUSITNA HYDROELECTRIC PROJECT SC SIDE CHANNEL T TRIBUTARY PLATE 18 OF 18 101SSSIDESLOUGH+RIVER MILE RIVERMILE TO 102 Trihey &MARZA-ERASCO US UPLAND SLOUGH -.hove ResoucsSpeaaists SUSITNA JOINT VENTURE a»a]24 t eeMS sc Ss US LEGEND MAINSTEM SIDE CHANNEL SIDE SLOUGH UPLAND SLOUGH ™TRIBUTARY MOUTH T TRIBUTARY +RIVER MILE ar aa _oo -y,Pa a RS tA,Goo " PLATE 18 OF 18 MIDDLE SUSITNA RIVER RIVERMILE 101 To 102 AresRAPS aeteeey >.a ALASKA POWER AUTHORITY SUSITNA HYDROELECTRIC PROJECT Ti &piney &os HARZAs ZRASCO SUSITNA JOINT VENTURE 6 ;SeRSyBoghe'oe ' eer SE Ore "a A ”re ' f an bat My eae e <be Ot+h 4 ab ep ie};ate aire.rd Pte RASA yetaNomee, = .ie' A cae RS -e aye wae 2%, Be y . AeA POSEpeeibehate.Ae wa SAR Wet.ae rad RtcrsreDoeta LEGEND MS MAINSTEM SC SIDE CHANNEL SS SIDE SLOUGH US UPLAND SLOUGH TM TRIBUTARY MOUTH T TRIBUTARY +RIVER MILE ALASKA POWER AUTHORITY SUSITNA HYDROELECTRIC PROJECTMIDDLESUSITNARIVER- PLATE 18 OF 18 RIVERMILE 101 To 102 Ascotiates |WARZA-EBASCOSe|SUSITNA JOINT VENTURE tts rm aaFey"fib8 Appendix 2.Habitat transformation In response to changing mainstem discharge.Surface areas and breachIng flows for middle Susitna River specific areas are presented.The specific areas are delineated on aerfal photography taken at 23,000 cfs. 3as 332SIn addition to surface area responding to changes In malnstem discharge, the type of habitat available In a specific area may also change in response to nalnstem discharge.This flow dependent change from one habitat type to another Is referred to as "habitat transformation."One example of a habitat transformation occurs when a side channel conveying turbid water becomes a clear water side slough as the mainstem discharge (stage)recedes to a level that prevents the flow of turbid mainstem water Into the upstream entrance to the side channel and clearwater flow Is malntalned in the channel by subsurface Inflow and Infiltration. Another common transformation occurs when mainstem habitat becomes side channel habitat as a result of decreasing mainstem discharge. Habitat transformations occur almost exclusively along the lateral margins of the river.Thus all wetted surface area present at 23,000 cfs which was not part of the main channel of the middle Susitna River was partitioned Into "specific areas".These were defined as discrete geographical locations whose physical boundaries enclose relatively homogeneous morphologic subareas of the middie Susitna River.Nearly all the wetted surface area of the specific areas at 23,000 cfs Is comprised of side channel,side slough,and upland slough habitats. Large side channels or side sloughs were occasionally subdivided Into two or more specific areas based upon thelr channel morphology.Some portions of the mainstem (primarily shoals and upwelling areas)were also delineated as specific areas.Each specific area was referenced to a river mile (RM)and the side of the river (looking upstream)on which It was focated:Jeft (L),right (R),or middle (M)If between two mainstem forks.Locations of the 172 specific areas are delineated on photo plates of the 23,000 cfs aerial photography (Plates 1-18). The methodology by which habitat transformations were tracked made use of aerfal photography of the middle Susitna River taken at mainstem discharges of 23,000;18,000;16,000;12,500;10,600;9000;7400;and 5100 cfs.At each discharge,the surface area of each specific area was measured and the habitat type the specific area respresented was determined.Eleven "habitat transformation categories"were developed to define the types of habitat transformations that a specific area might undergo as mainstem discharge declines (Aaserude et al.1985). Habitat transformations at each specific area were Identified through photo comparison.Individual specific areas were then grouped according to the sequence of habitat transformations they underwent as mainstem discharge decreased from 23,000 cfs to 5100 cfs (Aaserude et al.1985). The behavior (sequence of habitat transformation)of these specific areas in response to changing mainstem discharge served as one Index by which specific areas could be described. Another useful index by which specific areas were described and classified was breaching flow.Breaching flow Is defined as that mainstem discharge at which the head of a side channel or side slough Is overtopped by the mainstem river.Identification of habitat transformation sequence and breaching flows for Individual specific areas enabled grouping channels displaying similar characteristics into "representative groups".These groups served as the focal point In the analysis of habitat response to changes In mainstem discharge.Table A- 1 lists the mainstem discharges at which each of the specific areas becomes breached and Into which representative group each specific area was grouped.Table A-2 presents surface areas for each specific area at each of the seven malnstem discharges for which aerlal photography Plates 1-18.Specific areas of the middle Susitna River delineated on photography taken at a mainstem discharge of 23,000 cfs. ROP EF FLUE. RS SUE SINGS SR RES SE Sa RNSSEN IRS Fe Ee TES :See ete ee Shaswep sean EE Use abysPattont=ae 3 is x *ie ;marredeMeeeaeees ECts TNs nS.rhe PLAT Fae Ser eeeShe ALASKA POWER AUTHORITY SPECIFIC AREAS SUSITNA HYDROELECTRIC PROJECT MIDDLE SUSITNA RIVER at 23,000 cfs es Tihey &HARZAsEBASCOAssociates_Aquatic Resourceists SUSITNA JOINT VENTURE i CL STE LETT ereAyRYites:REG Be eaeoPee¢ eRe:ROR sat $fSEShat ann PEARS LEN ahas tee ec ed Pu ee AONE 'SCM *f nd%Syitne .aye Ie,e et ee oe ng he Maite,eRe:Hie ew ames 'a he <tara Saga >TREE ER Pere RE aie MeterE a aOR Sed ae he dian he SyOEHerelisORafEEEIEPieesandes CEA STR PNR LEAOPO TIES Sp TET IES SELES STI,wah NeMR Cin ORY AO Stan Es Aaa haSarAneaneeCOLESEGSERED,Bees Ok ED IA HO gOS GB Rayee ear ee aneeeeeq ae irs :oe,anteaters ;ELBE RCE RYnase atl ALASKA POWER AUTHORITY SPECIFIC AREAS SUSITNA HYDROELECTRIC PROJECT atMIDDLESUSITNARIVER 23,000 cts Viney a HARZA-EBASCOAssociatesGavatcResourceSUSITNAJOINTVENTURE zy ay BS)re]readMIDDLE SUSITNA RIVER hinge a "0 re SPECIFIC AREAS at 23,000 cfs ALASKA POWER AUTHORITY SUSITNA HYDROELECTRIC PROJECT Trihey & Associates Aquatic Resource Specialists HARZA*EBASGCO SUSITNA JOINT VENTURE Table Aci.Approximate breaching flows of specific areas of the middie Susitna River. Speci fic _Breaching Representative Specific Breaching Representative Area Flow (cfs)Group Area Flow (cfs)Group 100.40 R 12500 itl 115.60 R 23000 oO 100.60 R 33000 ti 116.80 R <5100 IV 100.60 L 9200 "aul 117.00 M 15500 Vv 100.70 R <5100 iV 117.10 M 15500 Vill 101.20 R 9200 Vl 117.20 M 20000 vill 101.30 M 9200 Vill 117.70 L <5100 IX 101.40 L 22000 (1 117.80 L 8000 tl 101.50 L <5100 1X |117.90 R 7300 VI 101.60 L 14000 1 117.90 L 22000 Ut 101.70 L 9600 ttl 118.00 L 22000 Hl 101.71 L MSS Vv 118.60 M 14000 Vill 101.80 L 22000 (1 118.91 £MSS V 102.00 L 10000 Vill Vi9.dd Lb MSS x 102.20 L US 1 119.20 R 10000 vil 102.60 L 6500 vi 119.30 L 16000 Hl 104.00 R <5100 IX 119.40 L US ! 104.30 M 21000 vill 119.50 L 5000 IV 105.20 R US {119.60 L -<5100 1V 105.70 R <5100 {X 119.70 L 23000 vi 105.81 L MSS X 119.80 L 15500 vill 106.30 R 4800 vi 120.00 R US 1 107.10 L 9600 vi 120.00 L 12500 veld 107.60 L US t 121.10 R <5100 x 108.30 L US t 121.10 L 7400 vil 108.70 L <5100 {Vv 121.50 R-19500 VUll 108.90 L <5100 1x 121.60 R°15500 vitt 109.30 M MSS X 121.70 R <5100 1Vv 109.40 R <5100 {X 121.80 R 22000 it 109.50 M 16000 vill 121.90 R US I 110.40 L 12000 ttt 122.40 R 26000 1 110.80 M <5100 tv 122.50 R 20000 tl 1117.00 R <5100 IX 123.00 L <5100 vil 111.50 R <5100 iV 123.10 R US 1 111.60 R 11500 X 123.20 R 23000 vill 112.40 L 22000 vill 123.30 R US J 112.50 L US !123.60 R 25500 a 112.60 L <5100 (Vv 124.00 M 23000 v 113.10 R 26000 Ut 124.10 L <5100 iV 113.60 R 10500 X 124.80 R 19500 vill 113.70 R 24000 tt 125.10 R 20000 It 113.80 R <5100 1X 125.20 R <5100 {Vv 113.90 R 7000 x 125.60 L <5100 Vil 114.00 R <5100 iV 125.60 R 26000 vill 114.10 R <5100 Vil 125.90 R 26000 te 115.00 R 12000 itl 126.00 R 33000 Vl MSS =Malnstem Shoal US =Upland Slough Specific BreachIng Representative Specific Breaching Representatlive Area Flow (cfs)Group Area Flow (cfs)Group 126.30 R 27000 ti 137.20 R 10400 tit 127.00 M <5100 tv 137.50 R 22000 I! 127.10 M <5100 {x 137.80 L 20000 if 127.20 M US {137.90 L 21000 ii 127.40 L <5100 (Vv 138.00 L 8000 vi 127.50 M <5100 vit 138.71 L MSS xX 128.30 R <5100 IX 138.80 R 6000 vi 128.40 R 9000 Vill 139.00 L US | 128.50 R 10400 (tt 139.01 L MSS v 128.70 R 15000 (tt 139.20 R <5100 (X 128.80 R 16000 til 139.30 L MSS xX 129.30 L <5100 (xX 139.40 L <5100 {V 129.40 R US (139.41 L MSS x 129.50 R <5100 {Vv 139.50 R -8900 vi 129.80 R <5100 IX 139.60 L <5100 {Vv 130.20 R 12000 itt 139.70 R 22000 v 130.20 L 8200 Vik 139.90 R US ( 131.20 R <5100 (xX 140.20 R 26500 | 131.30 L 9000 VU 140.40 R <5100 Vv. 131.70 L 5000 {Vv 140.60 R 12000 vt 131.80 L 26900 it 141.20 R <5100 1X 132.50 L 14500 Vill 141.30 R <5100 1X 132.60 L 10500 itt 141.40 R 11500 Hit 132.80 R 19500 Vv 141.60 R 21000 Vv 133.70 R 11500 itt 142.00 R 10500 vl 133.801 17500 vi 142.10 R 23000 it 133.81 R MSS x 142.20 R 26000 it 133.90 R 30000 (t 142.80 R <5100 [X 133.90 L US {142.80 L MSS x 134.00 L US |143.00 L 7000 Vv 134.90 R <5100 {Vv 143.40 €23000 (t 135.00 R 21500 Vii 144.00 R <5100 (X 135.00 L <5100 {x 144.00 M 22000 vill 135.10 R 20000 vill 144.20 L <5100 {Xx 135.30 L 23000 tt 144.40 L 21000 tl 135.50 R US {145.30 R <5100 {Vv 135.60 R 42000 t 145.60 R 22000 vill 135.70 R 27500 vi 146.60 L 26500 VEtl 136.00 L <5100 IV 147.10 L <5100 {xX 136.30 R 13000 vi 148.20 R MSS x 136.90 R US ' Table A-2..Surface areas by discharge for Individual specific areas of the middle Susitna River.Areas are in square Inches measured at a scaleof1Inch=1000 feet (1 square Inch =22.95 acres).The line indicates between which two analyzed discharges breaching of the ba ™"? FY i:e) 74 #?waradia ca Individual channel occurred. REPRESENTATIVE GROUP VIIt Oischarge (cfs) REPRESENTATIVE GROUP IX Olscharge (cfs) Specific Specific Area 5,100 7,400 10,600 12,500 16,000 18,000 23 ,000 Area 5,100 7,400 10,600 12,500 16,000 18,000 23 ,000 101.3 M 000 -000 -038 045 .097 .061*.108 101.5 L 1.343 1.278 1.208 1.239 1.651 1.698 2.661 102.0 L 000 .000 -058 -090 .098 -091 2123 104.0 R 641 -631 -631 .716 .698 -679 .887 104.5 M -000 -000 000 000 000 .065*|.036 105.7 R 2363 2419 -358 -407 -417 .389 447 109.5 M 000 .000 -000 .000 -000 014 -056 108.9 L -307 2272 -290 -2835 2333 -366 -401 112.4 L 000 .000 -000 -000 -000 .035 __|.143 109.4 R -917 951 -990 1.081 1.062 1.072 1.218 117.1 M -000 -000 000 071 {.271 -447*2422 111.0 R -896 -939 1.033 1.062 1.258 1.149*1.368 117.2 M -000 .000 -000 000 000 2024 045}113.8 R «135 2123 145 -154 171 -186 181 118.6 M -007 .025 -013 .021 034 .054 676 W727 6 173 -203 -162*218 292 .087*2d45 119.8 L -000 -000 -000 -000 -031 -091*.037 127.1 M -403 404 2442 -537 -628 738 -887 120.0 L -000 011 -036 -086 -160 -064* 244 128.3 R 684 815 -884 1.094 1.009 1.096 1.566 121.5 R -000 .000 -000 000 -034 2105 _|.294 129.5 L 179 181 -142*178 163 132*-266 121.6 R -000 .000 -000 -000 [.135.2339 -385 129.8 R 572 -626 619 618 -656 -463*-686 123.2 R 012 018 -023 025 -016 .055 -125 131.2 R 142 -185*.133 2139 -161 169 -226 124.8 R .000 .000 -010 -023 067 074 «262 135.0 L 2212 201 -190 2192 -202 .188*212 125.6 R -000 .000 -016 012 O11 -029 139.2 R 2434 458 516 -530 -583 510*662 128.4 R .000 -000 {_.052 2091 2132 -144 141.2 R 130 -189%194 142 2152 -056*«244 132.5 R 000 -000 000 -000 |-097 -054*141.3 R -294 -000*-297 -290 -288 .332 331 135.0 R .000 .000 .000 -000 04)-000*142.8 R 839 2925 1.100*.978 1.264 -582*1.305 135.1 R 000 -000 000 -058 -058 -000*144.2 L 1.846 1.787 1.133*1.127%1.838 -709*1.943 144.0 M .000 .000 .000 -000 -000 -000 147.1.L 2516 -903 2952 -497 2534 -611 675 145.6 R -000 000 000 -000 000 .180 . 146.6 L -000 -000 -000 .000 -000 010 *deleted from further analysis *deleted from further analysls