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HomeMy WebLinkAboutAPA2908- --._--.---------------~-~----------~-----~, ALASKA DEPARTMENT OF FISH AND GAME SUSITNA HYDRO AQUATIC STUDIES REPORT SERIES r TI( l~~5 .s?; A0'6 90~f\o" ALASKA DEPAR"rMENT OF FISH AND GAME SUSITNA HYDRO AQUATIC STUDIES REPORT NO.10 PRELIMINARY EVALUATIONS OF POTENTIAL FISH MITIGATION SITES IN THE MIDDLE SUSITNA RIVER Authors: Donald R.Seagren and Robert G.Wilkey Prepared for: ALASKA POWER AUTHORITY 33<4 W.FIFTH AVE. ANCHORAGE.ALASKA 99501 r""' i i - NOVEMBER 1985 ARLIS Alaska Resources "D.In fonnaUOl1 ServicesLibraryCKokAnchorage~Alas a - -I""- M..... C'\l...,....,. ooo l!) l!) I""- M M PREFACE This report is one of a series of reports prepared for the 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 River Aquatic Studies Program was initiated in November 1980. The studies described in this report were conducted in support of mitigation planning being done by ENTRIX,Inc.,the primary mitigation contractor.This report includes studie~conducted from July 1984 through April 1985 in the middle reach of the Susitna River from Talkeetna (RM 98.0)to the mouth of Devil Canyon (RM 150.0).The study exami ned general habitat characteri sti cs duri ng the open-water season and site specific incubation conditions during the ice-covered season. The open-water study examined general habitat characteristics (surface water quality,substrate,upwelling,passage,temperature,salmon spawning,etc.)of 44 slough and side channel sites in order to evaluate their potential to mitigate for adverse effects to salmon spawning and incubation habitats as a result of the proposed hydroelectric project. The ice-covered study examined incubation conditions (surface and intragravel water quality and temperature,and substrate composition)in these sites to further determine their suitability as potential mitigation sites.Each site studied exhibited general conditions (passage,substrate,etc.)that were similar to those found in other sites that proved to be limiting to salmon spawning. The combined data from these open-water and ice-covered studies will be used by ENTRIX,Inc.to help determine the suitability of habitat types (side slough,upland slough,side channel)and habitat modification methods for mitigation of adverse impacts to salmon spawning and incubation environments as a result of the proposed hydroelectric development. Questions concerning this report should be directed to: Alaska Power Authority 334 West 5th Avenue Anchorage,Alaska 99501 Telephone (907)276-0001 ARLIS Alaska Resources Library &InfonnatlOn Services Anchorage,Alaska r Report Number 1 2 3 4 5 6 7 8 9 10 TITLES IN THIS SERIES Publication Title Date Adult Anadromous Fish Investigations:April 1984 May -October 1983 Resident and Juvenile Anadromous Fish July 1984 Investigations:May -October 1983 Aquati c Habi tat and Instream Flow September 1984 Investigations:May -October 1983 Access and Transmission Corridor Aquatic September 1984 Investigations:May -October 1983 Winter Aquatic Investigations:March 1985 September 1983 to May 1984 Adult Anadromous Fish Investigations:June 1985 May -October 1984 Resident and Juvenile Anadromous Fish July 1985 Investigations:May -October 1984 Availabil ity of Invertebrate Food Sources July 1985 for Rearing Juvenile Chinook Salmon in Turbid Susitna River Habitats Summary of Salmon Fishery Data for August 1985 Selected Middle Susitna River Sites Preliminary Evaluations of Potential November 1985 Fish Mitigation Sites in the Middle Susitna River - ,.... I r r- I r- I: I r- i PRELIMINARY EVALUATIONS OF POTENTIAL FISH MITIGATION SITES IN THE MIDDLE SUSITNA RIVER Report No.10 by Donald R.Seagren and Robert G.Wilkey Alaska Department of Fish and Game Susitna River Aquatic Studies Program 620 East 10th Avenue Anchorage,Alaska 99501 ABSTRACT Development of the Susitna Hydroelectric Project is expected to alter the natural seasonal flow regime of the Susitna River downstream of Devil Canyon {RM 152.0}.Changes in the natural flow regime of the Susitna River may impact salmon spawning and incubation habitat in the middle reach of the river from Ta1keetna(RM 98.0}to Devil Canyon (R~l 152.0).This study was conducted by the Alaska Department of Fi sh and Game during 1984 and 1985 to evaluate potential slough and side channel sites that may be used to mitigate for adverse impacts to salmon spawn i ng and i ncuba t i on hab ita t reslJ lt i ng from opera t i on of the hyd ro- electric project.These evaluations focused on habitat modification as a mitigation alternative to improve fish passage,upwelling,and sub- strate conditions.Forty-four potential fish mitigation sites were identified during the open-water portion of this study.Of these 44 sites,23 were side slough habitats,16 were upland slough habitats,and 5 were side channel habitats.From the initial 44 sites,three repre- sentative sites were selected for more detailed evaluations of habitat modification alternatives during the ice-covered season.Baseline informati on on surface and i ntragrave1 water qua 1ity,substrate con- ditions,upwelling sources,and fish passage restrictions were collected during the open-water season.The ice-covered studies evaluated incubation conditions (water quality and substrate)and specific habitat modification techniques which may be applicable for mitigation purposes. Recommendations for specific sites which generally appear to be most suitable for mitigation are presented in the discussion.However,the selection of these sites was based on field observations and limited data,therefore a more detailed evaluation should be conducted to determine if these sites are the most practical sites for mitigation purposes.This study only evaluates the mitigation potential of sites under current habitat conditions and any changes to the habitat that may take place in the future may necessitate a reevaluation of these sites. i - TABLE OF CONTENTS ABSTRACT 11-D .. ...... .. ...... .. ...... ..i TABLE OF CONTENTS.,Ill (:I "'............................................ii -LIST OF FIGURES D •••••••••••••III .v LIST OF TABLESe Ill vi i i LIST OF APPENDIX FIGURES...........................................ix LIST OF APPENDIX TABLES .....••...•.•.•...••..•••....••••.•...•...•.xvii 1.0 INTRODUCTION..................................................................................................1 1.1 Background II ....................• -II....1 1.2 Objecttves...... .. .. ........ .. .. .............. .. .............. .. .. .. .. .......... .. .. .. .. .. .. ................ ..3 2 e 0 METHOD S II-II-.... .. .. .. ..6 2.1 Open-Water Studies..........................................6 2.1.1 Site Selection..........................................6 2.1.2 Surface Water Quality and Intragravel 2.2 Ice-Covered Studies e •••••••••••••••••••••••••••••••-I i 2.1.3 2.1.4 2.1.5 2.2.1 2.2.2 2.2.3 2.2.4 Water Temperature .....III ••••••••••••••••••••••••••••••••• General Substrate Evaluations •.........•......•.•••..•.. Upwelling and Bank Seepage •.•••••.•.•..•.••.•........•.. Evaluations of Passage Restrictions .•..............•.•.• Sit'e Selection . Surface and Intragravel Water Quality ........•........•. Freeze Core Substrate Analysis ......••.....•.•.•.•..•.•. Upwelling and Bank Seepage .....•..•..•...•.......••.•.•. 6 14 15 15 15 15 16 17 21 2.3 Interpretation of Figures...................................21 ii Table of Contents (Continued) 3.0 RESULTS ••.•.•e ••IIl •••G ••••••••••••••••~•••••IIl.IIl •.&~.'O......•....23 3.1 Open-Water Studies Ill ••.•.."••..•......•Ill "Ill.....23 ~, 3.1.1 Instantaneous Surface Water Quality and Intragravel Water Temperatures..........................23 3.1.2 General Substrate Evaluations...........................23 3.1.3 Upwelling and Bank Seepage....•.•....•...••.•.23 3.1.4 Evaluations of Fish Passage Restrictions................28 3.1.5 Salmon Spawning Utilization.............................29 3.2 Ice-Covered Studies ....•..•.•••.•.•••.~e ....e.8.............30 3.2.1 Physical Characteristics.••••••••.••••••..•..•..••......30 3.2.1.1 Water Temperature .•....•....•.....•••...~...........30 3.2.1.1.1 Instantaneous Surface and Intragravel Water Temperatures..............................31 3.2.1.1.2 Continuous Surface and Intragravel Water Temperature......... .... . . . ................. . . . .31 3.2.1.2 Freeze Core Substrate Analysis....•....31 3.2.1.3 Upwelling and Bank Seepage...•.....•...•.....•.•...•40 3.2.2 Chemical Characteristics................................40 3.2.2.1 Dissolved Oxygen •.•••~..............................40 3.2.2.2 pH CI.........................41 3.2.2.3 Conductivity eo.llco e..........41 4.0 DISCUSSION....................................................54 4.1 General Evaluations of Potential Mitigation Sites at Side Slough~Upland Slough and Side Channe 1 Habi tats III • • • • • • • • • • • • •54 4e1.1 Side Channel Habitats...................................54 4.1.2 Upland Slough Habitats..................................54 4.1.3 Side Slough Habitats....................................55· 4.2 Opening of Beaver Dams to Improve Fish Passage Conditions .......••e •••••••o ••Il •••••••8 ••••~•••••e..56 4.3 Identification of Habitat Modification Techniques at Selected Slough Sites.........................56 4.3.1 Bushrod Slough..........................................57 4.3.2 Curry Slough............................................58 4.3.3 Slough 10......59 iii .~ - - ..... .... - - - - - TABLE OF CONTENTS (Continued) 4.4 Conclusions/Recommendations..••••.•..60 5.0 CONTRIBUTORS .•••.•...••••••...•.•..••••••••••••.•...II •••••11 ••5 62 6"a ACKNOWLE,DGEMENTS ••••••••••••ill •••••••••••••••••••••••••••0 • • • • •63 7.0 LITERATURE CITED..............................................64 8.0 APPENDIC·ES .•........•...•••.•e •••••••••••••••••••Il ••••••••ce..70 Appendix A.Site Descriptions and Site Maps .•...........•.•.A-I Appendix B.General Surface Water Quality and Intragravel Water Temperature Data ...••....•...•...•••.•••..B-1 Appendix C.Salmon Spawning Distribution Data ••.............C-l Appendix D.Selected Physical and Chemica] Requirements for Various Life Stages of Salmon Species ....•..•.•.•.•..........0-1 Appendix E.Winter Water Quality Data ..•.........•...••....•E-l Appendix F.Freeze Core Substrate Data ...........•...•.•....F-l iv LIST OF FIGURES Figure Ti tle 1.Map of the fish mitigation site study area in the Susitna River basin,1984-1985 .......••.•••.•••••••.2 2.General spawning habitat preference of the five species of salmon utilizing the Susitna River basin ",...4 7 9 8 11 """ -13 12 10 Maps of the middle Susitna River from RM 98.0 to 101.5 showing study sites and open leads ......•...... Maps of the middle Susitna River from RM 101.5 to 110.5 showing study sites and open leads ....•••...•.. Maps of the middle Susitna River from RM 110.5 to 120.5 showing study sites and open leads . Maps of the middle Susitna River from RM 120.5 to 128.5 showing study sites and open leads ..........•.• Maps of the middle Susitna River from RM 128.5 to 137.5 showing study sites and open leads . Maps of the middle Susitna River from RM 137.5 to 144.5 showing study sites and open leads .•••.••..•... Maps of the middle Susitna River from RM 144.5 to 150.0 showing study sites and open leads ••........... Diagram of polyvinyl chloride (PVC)standpipe used to evaluate intragravel water conditions in streambeds of salmon spawni ng habitats in the middle reach of the Susitna River...................18 9. 5. 7. 3. 8. 4. 6. 10. - - Comparison of the range and mean at dissolved oxygen,conductivity,and pH measured at side slough,upland slough,and side channel habitats by sampling period,1984.......................27 Single probe freeze core apparatus used to sample streambed substrates in the middle reach of the Susitna River,1985 ....•.••...•.•...•.•...19 Definitions of symbols used in boxplots which summarize water temperatures, dissolved oxygen,pH,and conductivity data........................22 13.Comparison of the range and mean of instantaneous surface water and intragravel water temperatures measured at side slough, upland slough,and side channel habitats by sampling period,1984...................................26 11. 14. 12. v ,...., LIST OF FIGURES (Continued) Fi gure Ti tle 15.A comparison of instantaneous surface and intragravel water temperature data (OC) measured at standpipes in Bushrod Slough, Curry Slough,and Slough 10 during the ice-covered season,1984-85 •.•.•.•.•.•...•..............32 16.Summary of instantaneous surface water temperature data (OC)measured at standpi pes in the middle reach of the Susitna River,by study site and sampling period,ice-covered season 1984-1985 •.....•e••••••o~••6 ••eo~•...o.e.~c......33 17.Summary of instantaneous intragravel water temperature data (OC)measured at standpipes in the middl e reach of the Susitna River,by study site and sampling period,ice-covered season 1984-1985 0 e ..III 0 ..34 18.Mean daily intragravel and surface water temperature (OC)recorded at Bushrod Slough, (RM 117.9),during the 1984-85 ice-covered season.......35 - 19. 20. Mean daily intragravel and surface water temperatures (OC)recorded at Curry Slough (RM 119.7),during the 1984-85 ice-covered season .•..••..... Mea'n daily intragravel and surface water temperatures (OC)recorded at Slough 10 Northeast (RM 113.8),during the 1984-85 ice-covered season . 35 36 r ! 21. 22. Mean daily intragravel and surface water temperatures (OC)recorded at Slough 10 Northwest (RM 133.8),during the 1984-85 i ce-cov.ered season II .. ..36 A comparison of surface and intragravel dissolved oxygen concentration data (mg/1) measured at standpipes in Bushrod Slough, Curry Slough,and Slough 10 duri ng the ice-covered season,1984-85.............................42 23.A comparison of surface and intragravel percent oxygen saturation data measured at standpipes in Bushrod Slough,Curry Slough, and S10ugh 10 duri ng the ice-covered season, 1984-85 --e-•••••e ••• •..••43 vi LIST OF FIGURES (Continued) Figure Ti tle ...,. - 26.Summary of surface water percent oxygen saturation data measured at standpipes in the mi ddl e reach of the Sus i tna Ri ver,by study site and samp1 ing period,ice-covered season 24. 25. 27. Summary of surface water dissolved oxygen data (mg/1)measured at standpipes in the middle reach of the SusitnaRiver,by study site and sampling period,ice-covered season,1984-85 . Summary of intragrave1 water dissolved oxygen data (mg/l)measured at standpipes in the middle reach of the Susitna River by study site and samp 1i ng peri od,ice-covered season 1984-85 III CI -0 o •••CI ••••••••••• 1984-85 C1 ••••••II ••e-•••••••••••••••• Summary of intragravel water percent oxygen saturation data measured at standpipes in the middle reach of the Susitna River,by study site and sampling period,ice-covered season 1984 -85. . . . . . . . . . . . . . . . . . . . .-0 • • •••••••41 • • •., 44 45 46 47 - - - """ 28. 29. 30. 31. 32. A compari son of surface and intragravel pH data measured at standpipes in Bushrod Slough, Cu rry Slough,and Slough 10 du ri ng the ice-covered season,1984-85.............................48 Summary of surface water pH data measured at standpipes in the middle reach of the Susitna River,by study site and sampling period, ice-covered season 1984-85..............................49 Summary of intragravel water pH data measured at standpipes in the middle reach of the Susitna River,by study site and sampling period,ice-covered season 1984-85......................50 A compari son of surface and intragravel conductivity data (umhos/cm)measured at standpipes in Bushrod Slough,Curry Slough, and Slough 10 duri ng the ice-covered season, 1984-85 ill C1 -0 41 .."II)III .. .. .. .. .. ..51 Summary of surface water conductivity data (umhos/cm)measured at standpipes in the middle reach of the Susitna,by study site and sampling period,ice-covered season 1984-85.............52 vii - - 'LIST OF FIGURES (Continued) Fi gure Title .- r- I I I - 33.Summary of intragravel water conductivity data (umhos/cm)measured at standpipes in the middle reach of the Susitna,by study site and sampling period,ice-covered season 1984-85 •••.••••••••• viii 53 LIST OF TABLES Table 1. 2. Title Page Substrate classification scheme utilized to evaluate general substrate composition at slough and side channel study sites..................14 Summary of selected site characteristics of potential mitigation sites surveyed in the middle reach of the Susitna River,1984..............24 3.Summary of computed substrate qual ity indices at Bushrod Slough (RM 117.9L)................38 4.Summary of computed substrate quality indices at Curry Slough (RM 119.7R)................•.38 5.Summary of computed substrate quality indices at Slough 10 (RM 133.8L)..........•••........39 ix LIST OF APPENDIX FIGURES Appendix Figure Ti tle ",.. - .... A-I. A-2. A-3. A-4. A-5. A-6. A-7. A-8. A-9. A-IO. A-II. A-12. A-13. A-14. A-IS. A-16. Substrate composition and sampling locations in Slough 1 (RM 99.SR).•.•.•••.•...•.•••••.•.•.... Salmon spawning locations in Slough I (RM 99.5R)............•.•.......•...........•.•....... Upwelling and salmon spawning areas in Slough 2 (RM 100.7R)-'iii Substrate composition and sampling sites in S10 ug h 2 (RM 100.2 R)•••••••••••••••••••••••••••••• Substrate composition of Whiskers Slough (RM lOl ..2L). Upwelling areas and sampling sites in Whiskers Slough (Rm 101.2L)•.•.•.•.......•........ Pink and chinook salmon spawning areas in Whiskers Slough (RM 101.2L)....................•.. Coho salmon spawning areas in Whiskers Slough (RM 101.2L)...•..........-;.. Channel configuration and upwelling areas in Slough 38 (RM 101.4L)and Slough 3A (RM lOl.9L)'.. Substrate composition of Slough 38 (RM 101.4L)and Slough 3A (RM 101.9L).•............... Salmon spawning areas in Slough 3B (RM 101.4L)and Slough 3A (RM 101.9l).............•... Sampling locations in Slough 38 (RM 101.4L) and Slough 3A (RM 101.9L)•.........•.......•...•.. Channel configuration,substrate composition and sampling site in Slough 4 (RM 10S.2R)........• Channel configuration,substrate composition and sampling sites in Slough 5 (RM 107.6L)•.•..... Channel configuration,bank seepage and sampling sites in Slough 6 (RM 108.2L).•.•.....•.. Substrate composition in Slough 6 (RM 108 ..2l )-.. x A-3 A-4 A-5 A-7 A-8 A-9 A-lO A-ll A-12 A-13 A-15 A-16 A-17 A-19 A-20 A-21 LIST OF APPENDIX FIGURES (Continued) -, Appendix Fi gure A-17. A-18. A-19. A-20. A-21. A-22. A-23. A-24. A-25. A-26. A-27. A-28. A-29. A-3D. A-31. A-32. A-33. Title Upwelling and substrate composition in Oxbow I side channel (RM llD.Ol).••...•..•..••••••.•••.• Sampling sites and chum salmon spawning areas in Oxbow I side channel (RM IID.Dl)•...•••••..•.•. Substrate composition and bank seepage areas in Slough 6A (RM II2.3L)....•....•.......•........ Sampling locations in Slough 6A (RM Il2.3l)...•... Substrate composition,sampling locations and upwelling areas in Slough 7 (RM II3.2R)•••.••..... Substrate composition of Slough 8 (RM 113.7R). Upwelling and bank seepage areas in Slough 8 (RM 113.7R)•.•.•...•.•....•....................... Chum salmon spawning areas in Slough 8 (RM 113.7R).. Sockeye and pi nk sa 1man spawn i ng areas and sampling locations in Slough 8 (RM 113.7R). Channel geometry and sampl ing sites in Mainstem Two Side Channel (RM 114.5R)•.•...•.•.... Substrate composition and bank seepage areas in Mainstem Two Side Channel (RM Il4.5R).....•.... Passage reaches in Mainstem Two Side Channel (RM 114.5R)..............•.............Il . Chum salmon spawning areas in Mainstem Two Side Channel (RM 114.5R).........•...•••........... Channel geometry and sampling locations in Bushrod Slough (RM 117.9l).. Substrate composition and upwelling areas in Bushrod Slough (RM 117.9L). Chum and pink salmon spawning areas in Bushrod Slough (RM 117.9L)....•....•..........•... Standpipe locations in Bushrod Slough (RM 117.9L). xi A-22 A-24 A-25 A-26 A-27 A-29 A-3D A-31 A-32 A-33 A-34 A-35 A-36 A-38 A-39 A-4D A-41 -. Title ..... LIST OF APPENDIX FIGURES (Continued) Appendix Figure - r i l -- - A-34. A-35. A-36. A-37. A-38. A-39. A-40. A-41. A-42. A-43. A-44. A-45. A-46. A-47. A-48. A-49. Channel geometry,sampling locations and chum salmon spawning areas in Curry Slough (RM 119.7R}.-iIIClo. Substrate composition and upwelling areas in Curry Slough (RM 119.7R)•......................... Standpipe locations in Curry Slough (RM 119.7R)o.~. Channel geometry and upwelling areas in Slough 8C (RM 121.8R)and Slough 80 (RM 121.8R).,.e •••••o •••• Substrate composition in Slough 8C (RM 121.8R)and Slough 80 (RM 121.8R)••.••••••••.••••• Chum salmon spawning areas and sampling locations in Slough 8C (RM 121.8R)and Slough 8Q (RM 121.8R)............•.............•.•....... Channel geometry,upwe 11 i ng areas and sampling locations in Slough 88 (RM 122.2R)••••.•. Substrate composition in Slough 88 (RM 122 ..2R)-flo ill .. Spawning areas in Slough 88 (RM 122.2R)••••••••••• Substrate composition in Moose Slough (RM 123.1R). Upwell ing and bank seepage areas in Moose 510ugh (RM 123 ..1R).. Chum salmon spawning areas in Moose Slough (RM 123.1R)....................................•.... Sockeye salmon spawning areas in Moose Slough (RM 123 ..1R). Substrat1 composition and upwelling areas in Slough A (RM 124.6R)••••••••••••••.•••••••••.•••• Chum salmon spawning areas in Slough A1 (RM 124.6R).......•.•.•..............................• Pink salmon spawning areas in Slough A1 (RM 1.24.6R).....•......•..............•...•........... xii A-43 A-44 A-45 A-46 A-47 A-48 A-50 A-53 A-54 A-55 A-56 A-58 A-59 A-60 Title LIST OF APPENDIX FIGURES (Continued) Appendix Figure '""'" A-50. A-51. A-52. A-53. A-54. A-55. A-56. A-57. A-58. A-59. A-60. A-61. A-62. A-63. A-64. A-65. A-66. Substrate composition and upwelling areas in Slough A (RM 124.8R)•.•••....•••.••••••••••.•••.•• Chum salmon spawning areas and sampling locations in Slough A (RM 124.8R)•••••;•••.•..•.•. Channel geometry and sampling locations in Slough 8A (RM 125.3R).....•••..•...•.••..••....... Substrate composition in Slough 8A (RM 125.3R}........................•...•..........o ••• Passage reach locations in Slough 8A (RM 125.3R)$••••••••••••••••Co e •••••••Co ••• Chum salmon spawning areas in Slough 8A (RM 125.3R)...Co •••••••••••II ••~•••••••e •••••••••••••••CI Sockeye salmon spawning areas in Slough 8A (RM 125.3R)05 ••• Pink and coho salmon spawning areas in Slough 8A (RM 125.3R).....c •••••••••••••••••••••••••••••• Substrate composition t bank seepage and sampling locations in Slough B (RM 126.3R)..•..... Chum salmon spawning areas in Slough B (RM 126.3R)~s ••••••e ell."" Sockeye and pink salmon spawning areas in Slough B (RM 126.3R). Upwelling areas and passage reaches in Slough 9 (RM 128.3R).•..................Cl •••••••••••••••• Substrate composition in Slough 9 (RM 128.3R). Chum salmon spawn"ing areas in Slough 9 (RM128.3 R)...._e e e __e __~eo e e ill __ Sockeye and pink salmon spawning areas in Slough 9 (RM 128.3R)•...•...•............•...•.•.. Substrate composition and upwelling areas in Slough 98 (RM 129.2R).................•.•.•....... Chum salmon spawning areas in Slough 9B (RM 129_2R)..•_•••••.•••••.••••.•.••••II •••••••_••• xiii A-61 A-62 A-64 A-65 A-56 A-67 A-68 A-69 A-70 A-71 A-72 A-74 A-75 A-76 A-77 A-78 A-80 ~I ..... - ..... ..... - """I Title LIST OF APPENDIX FIGURES (Continued) Appendix Figure .- - - A-67 . A-68. A-69. A-70. A-71. A-72. A-73. A-74. A-75. A-76. A-77. A-78. A-79. A-80. A-81. A-H2. A-83. Sockeye salmon spawning areas in Slough 96 (RM 129 ..2R)•.G •••••••••II •••II o.Cl o.G-••Co ••••••••••••III Passage reaches and upwelling areas in Slough 9A (.RM 133.2R). Substrate composition in Slough 9A (RM 133.2R). Chum salmon spawning areas in Slough 9A (RM 133.2R}e ••••••••••••••• Sockeye salmon spawning areas in Slough 9A (RM 133.2R)••. . •••. . . . . •. •. ••••. •. . . . ••. •. . . ....... Channel geometry and sampling locations in Slough 10 (RM 133.8L)•.••••••••••••••••••.•••••••• Substrate composition in Slough 10 (RM 133.BL)c__•••••••• Upwelling and bank seepage in Slough 10 (RM 133.8L)II ••••••••••••••• Chum salmon spawning areas in Slough 10 (RM 133.8L)-II . Standpipe locations in Slough 10 (RM 133.8L)..•••• Chum salmon spawning areas in Slough 11 (RM 135.3·R). Sockeye salmon spawning areas in Slough 11 (RM 135.3R)..•.•...•.••....•.......•.......•-.. Pink salmon spawning areas in Slough 11 (RM 135.3R)...........•.....................•......... Passage reach locations and upwelling areas in Slough 11 (RM 135.3R)•••••••••••••••••..••••••• Substrate composition in Slough 11 (R,.,l 135.3R). Upwelling areas and sampling sites in Slough 12 (RM 13S.4R)and Slough 13 (RM 13S.SR}•••••••••• Substrate composition in Slough 12 (RM 135.4R)and Slough 13 (RM 135.5R}••.••••••••••.••• xiv A-81 A-82 A-83 A-84 A-8S A-86 A-8S A-89 A-gO A-91 A-92 A-93 A-94 A-9S A-96 A-98 A-99 LIST OF APPENDIX FIGURES (Continued) Appendix Figure A-84. A-8S. A-86. A-a7. A-aa. A-a9. A-90. A-91. A-92. A-93. A-94. A-9S. A-96. A-97. A-9a. A-99. Title Chum salmon spawning areas in Slough 13 (RM 135.5R)CllIl ••••••••••••••••••• Channel geometry and sampling sites in Upper Side Channel 11 (RM 136.oR)•••••.•••••.•..•.•••.•• Passage reaches and upwelling areas in Upper Side Channel 11 (RM 136.oR).............•.••..•.•. Substrate composition of Upper Side Channel 11 (RM 136.0R)"e •••••""•••eo Chum salmon spawning areas in Upper Side Channe 1 11 (RM 136.OR)..•.....•••..•..•..........• Channel geometry,substrate composition and sampling sites in Slough 14 (RM 136.0L)..••..•.... Channe 1 geometry,samp 1i ng site,and upwe 11- ing areas in Slough 1S (RM 137.2L)•......•••..•... Substrate composition in Slough 15 (RM 137.2L)II •••••••••••••••••••••••• Chum and pink salmon spawning areas in Slough 15 (RM 137 ..2l )flo flo ...0 II II eo III .. Substrate composition of Slough 16 (RM 137.7L)and Slough 16B (RM 137.9L). Chum salmon spawning areas and sampling locations in Slough 16 (RM 137.7L)and Slough 16 B (RM 137.9l )ill .. Channel geometry and sampling sites in Slough 17 (RM 138.9L}-5 .. Substrate composition and upwelling areas in Slough 17 (RM 138.9L)..•.•.•••..•..•.•....•...•..• Chum salmon spawning areas in Slough 17 (RM 138 ..9l ).. .. .. ...... .. .. .. ..'".. .. .. .. ..c .... ..III .... .. .. .. .. ...... .. .. ..Co Sockeye salmon spawning areas in Slough 17 (RM 138 ..9l )III •1&•• Substrate composition and spawning areas in Slough 18 (RM 139.1L)•.•.•.•••.•••......•.•.•..... xv A-100 A-101 A-102 A-I04 A-lOS A-106 A-107 A-lOB A-lID A-1ll A-112 A-114 A-llS A-116 A-1ll A-lIB ~i ""'", - - LIST OF APPENDIX FIGURES (Continued) - Appendix Fi gu re A-lOO. A-101. A-102. A-103. A-104. A-105. A-106. A-1D7. A-lOB. A-109. A-110. A-111. A-112. A-l13. A-114. A-115. A-116. Title Channel geometry and sampling locations in Slough 19 (RM 139.8R)••••••••••••••••••••••••••••• Substrate composition in Slough 19 (R~l 139.8R)~. Passage reaches and upwell i ng areas in Slough 19 (RM 139.8R)CIo •••••••••••••e ••••••••••••• Chum salmon spawning areas in Slough 19 (RM . 139 .8 R)"Q •• -eo ••• Sockeye salmon spawning areas in Slough 19 (RM 139.,8R)III ••••••CI ••••••CI •Cl .0 •• Substrate composition in Slough 20 (RM 140 •1R)•••••••••••••••••••••••••••e •••••ill ••••••••• Chum salmon spawning areas and passage reaches in Slough 20 (RN 140.1R)••.••••••••.••.••• Pink salmon spawning areas in Slough 20 (RM 140 . 1R).. Channel geometry and sampling sites in Side CHan ne 1 21 (RM 140.6R)•••••••••••••••••••••••••••• Substrate composition and upwelling areas in Side Channel 21 (RM 140.6R)••••••••••••••••••••••• Passage reaches and pink salmon spawning areas in Side Channel 21 (RM 140.6R)•••••••.•••••• Chum and sockeye salmon spawning areas in Side Channel 21 (RM 140.6R)••••••••.•••••••••••••• Channel geometry and sampling sites in Slough 21 (RM 141.8R)fil ••••••••••••••Cl ••• Substrate composition and upwelling areas in Slough 21 (RM 141.BR)••••••••••••••••••••••••••••• Chum and sockeye salmon spawning areas in S1au gh 21 (RM 141.8R )•••••••••••••.••••••••••••••• Upwelling areas,passage reaches and sampling sites in Slough 22 (RM 144.2L)•••••.••.•.••••.•••• Substrate composition in Slough 22 (RM 144.2L)-. xvi A-1l9 A-121 A;.,122 A-123 A-124 A-125 A-126 A-127 A-128 A-130 A-131 A-132 A-133 A-134 A-135 A-137 A-138 Title LIST OF APPENDIX FIGURES (Continued) Appendix Figure A-1l7. A-llB. A-1l9. A-120. A-121. Chum and pink salmon spawning areas in Slough 22 (RM 144.2L) . . . . . . . . . . . ..•G • • • • • • • • • • • • • •c.• • • •~• Channel geometry and sampling sites in Slough 21A (RM 145.3R}••••••••.••••••.••••.•.•II ••••••••c.. Upwe 11 i ng and bank seepage areas in Slough 2IA (RM I45.3R).............................•....• Substrate composition in Slough 2IA (RM 145 .3 R)Ii ••••••• Chum salmon spawning areas in Slough 2IA (RM 145.3R)....c.••••••.•••••••••••••••••••••••••••••••• xvi i A-139 A-140 A-14I A-142 A-143 ""'" ~I - LIST OF APPENDIX TABLES Appendix Table Title B-1.General surface water quality measurements and intragravel water temperatures in selected sloughs and side channels in the middle reach of the Susitna River,1984..........................B-2 C-1.Salmon spawning distribution in the middle reach of the Susitna River,1981-1984 (adapted from Barrett et al.1985)...........................C-2 D-1.Water temperature,dissolved oxygen,pH and substrate requirements for various life stages 1 of salmon spec;es ..o o..~~e...........0-2 r ! 0-2. E-1. F-1. Literature review of salmon redd depths by species in Alaska and the Pacific Northwest ....•••.. Intragravel and surface water quality data collected at standpipe locations at Bushrod Slough (RM 117.9L),Curry Slough (RM 119.7R) and Slough 10 (RM 139.8L)from November,1984 to May,1985,Susitna River,Alaska •.........••..•.. Substrate composition of samples collected using a freeze core sampler at three selected sloughs,March 1985 to April 1985,Susitna R;ve r,A1as k-a.CI •••••••II e 9 CI ..e . xviii 0-10 E-2 F-2 P" I ! r 1.0 INTRODUCTION This.report evaluates slough and side channel habitats in the middle reach of the Susitna River to identify potential sites that may be used to mitigate for adverse effects of proposed hydroelectric development on salmon resources in this reach of the river (Figure 1).A limited evaluation of beaver dam removal as a possible mitigation technique is also presented.The report presents data which was collected during open-water (June 30 to October 12,1984)and ice-covered (November 14, 1984 to May 1,1985)sampling periods.The information presented in this report is intended primarily to supplement mitigation planning which is being done by ENTRIX,Inc.(Moulton et ale 1984). 1.1 Background Operation of the Susitna Hydroelectric Project is expected to alter the natural seasonal flow regime of the Susitna River downstream of Devil Canyon (RM 152.0)(Acres 1982).Under the proposed operating scheme the present seasonal flow fluctuations will be altered,resulting in a more stabilized annual flow regime (Acres 1982).Such changes in the natural flow regime of the Susij:na River may result in a net loss of presently available salmon spawning habitat due to passage restrictions,reduced upwelling,loss of wetted usable habitat,or other discharge related effects (Moulton et ale 1984;Sa~tner et ale 1984). To insure that there is no net loss of fisheries production,the Alaska Power Authority (APA)has supported mitigation measures focusing on mainta i ni ng exi sting habitat or provi di ng repl acement habitat of suffi- cient quality and quantity to maintain the productivity of the present natural populations (Acres 1983).Mitigation alternatives that have been proposed to meet these goals include:1)altering the discharge release regime of the reservoir during the critical spawning period to provide passage and increased wetted surface area for spawning;2) mechanically altering the channels of the currently used spawning sites to increase passage and available spawning area;3)increasing head berm elevation to prevent winter overtopping of currently used spawning sites;or 4)locating replacement habitats that exhibit similar con- ditions under projected with-project conditions to those currently used for spawning and rearing. The initial mitigation plan developed for the Susitna Hydroelectric project was presented in Acres (1983).A recent fish mitigation plan for the Susitna River was developed by Woodward-Clyde Consultants (Moulton et ale 1984)that focused on flow release combined with physical modification of habitat as a mitigation alternative.The Woodward-Clyde study focused on four slough habitats (Sloughs 8A,9,11 and 21)which have been the focus of other studies relating to this project (Vincent-Lang et ale 1984)and which have traditionally supported the majority of chum and sockeye salmon spawning among slough habitats (Barrett et ale 1984,1985).Although Moulton et ale (1984) presents a potential fish mitigation plan for these selected sites, there is no assurance of success and there may be other sites whi ch 1 N o ....•••0 ..",p ----/..-- I I I I l ".......... "-"'-'-... "'"" I / ,,/ / I I / / / ./' \ ".......~",~ '\ \ \, I I I ~I I / SUSITNA RIVER Bl MIDDLE RIVER STUDY ~AREA DRAINAGE BOUNDARY o 2!l I I MILES (Appro •.SCQI,) Figure 1.Map of the fish mitigation site study area in the Susitna River basin,1984-1985. t J ,,.J J ~I J ~J 1 n J J J - ..... ,~ - - P" l present feasible mitigation options.For these reasons,baseline evaluations were conducted to identify all potential mitigation sites in the middle Susitna River so that they may be considered in future mitigation planning. The middle reach of the Susitna River was selected for study because the most significant changes in the existing physical characteristics of aquatic habitats are expected to occur in this reach.Slough and side channel habitats in this reach were selected as the primary focus of study because they are used by several species of salmon for spawning (Figure 2)and appear to provide the greatest potential for mitigation for adverse impacts to salmon spawning habitat resulting from proposed hydroelectric project.The 1984 estimated salmon spawning escapement to the middle reach of the Susitna River was approximately 7,180 chinook salmon,2,427 sockeye salmon,27,350 pink salmon,26,050 chum salmon, and 2,900 coho salmon (Barrett et al.1985).Side channel and slough habitats presently support approximately 71%of the estimated chum and 100%of the estimated sockeye salmon spawning which presently occurs in the middle reach of the Susitna River (Barrett et al.1985).For this reason,chum and sockeye salmon are the primary species of interest in thi s report. 1.2 Objectives This_was initiated d~ring July 1984.Initial sampling during the open-water season consisted of a preliminary evaluation of slough and side channel habitats in the middle reach of the Susitna River to identify those sites that may have potential for providing additional sa 1man spawni ng habitat under anti ci pated with-project conditi ons by using habitat modification techniques.Although these studies evaluated factors limiting to salmon spawning under present-flow condition,the sites which were selected appeared to be suitable for fish mitigation under general with-project flow regime of 9,000 to 12,000 cfs.This flow regime is a composite of Case EVand EVI scenarios that are pres- ently under consideration (Harza-Ebasco 1984).The data will be used in development of the Second Interim Mitigation Report by ENTRIX,Inc.The surveys evaluated general habitat characteri stics (substrate composi- tion,water temperature,water quality,upwelling,fish passage)present in each of the sites.Data from these surveys were used to assist in identifying potential sites for habitat modification as an alternative for maintaining naturally occurring salmon populations during operation of the proposed hydroelectric project.Additional sampling was con- ducted during the ice-covered season to identify specific habitat modification techniques for possible use at the potential mitigation sites to determine the feasibility of implementing such mitigation a lternati ves. The present study was specifically designed to supplement previous mitigation plans (Moulton et al.1984)and to provide additional infor- mati on to evaluate potent;a 1 miti gati on a 1 ternati ves by addressi ng the following objectives: 3 SPAWNING HABITAT PREFERENCE MS se SL T - MS -MAINSTEM SC -SIDE CHANNEl- SI--UPLAND Gild SIDE SLOUGHS T -TRIBUTARIES it'-PRIMARY SPAWNING HABITAT t -SECONDARY SPAWNING HABITATt-INCIDENTAL SPAWNING HABITAT MS SC •\ \,, \ COHO MS SC SL T CHI NOOK SOCKEYE MS SC SI-T PIN K MS se SL T CHUM ~, Figure 2.General spawning habitat preference of the five species of salmon utilizing the Susitna River basin (derived from data in Barrett et a1.1984). 4 ~- ,- 1) "'"' .,.., - r I r Evaluate slough and side channel habitats in the middle reach of the Susitna River to identify sites for mitigation of adverse impacts resulting from development of the Susitna Hydroelectric Project. 2)Remove fish passage restrictions (i.e.beaver dams)from selected slough habitats during the salmon spawning period to determine the feasibility of this technique as a mitigation option. 3)Evaluate intragravel conditions at selected potential mitiga- tion sites to determine suitability of the incubation environment for salmon embryos. 4)Evaluate the applicability of physical modification of habitat as a viable mitigation option at selected potential mitigation sites. 5 - -I i ..... 2.0 METHODS The fish mitigation site studies were conducted during the open-water fi e1d season (June 30 to October 12,1984)and the ice-covered fi e1d season (November 14,1984 to May 1,1985).The open-water studies consisted of a general evaluation of slough and side channel habitats as potential mitigation sites in the middle Susitna River (Figures 3-9). The ice-covered studies were more intensive evaluations of incubation conditions and potential habitat modificatiun techniques at three potential mitigation sites. 2.1 Open-Water Studies 2.1.1 Site Selection Forty-four sites,considered representative of the habitat types utilized by spawning chum and sockeye salmon in the middle Susitna Ri ver,were selected for study duri ng the open-water phase of these studies (Figures 3-9).Sampling sites for this study were selected from 1ocati ons where sa 1mon spawni ng ground surveys had been conducted by ADF&G (Barrett et ale 1985).Sampling sites were selected from each habitat type where salmon spawning has been documented (Barrett et ale 1985)• In addition to the regularly surveyed sites,aerial photos taken during March,1983 were used to locate open leads in the ice cover to identify any potential spawning sites that had not been previously surveyed for spawning activity.Open leads are generally indicative of either upwelling or high water velocities.Ground surveys were later conducted at these sites to determine if upwelling was present.Sites with upwelling were included as potential mitigation sites because chum salmon prefer areas with upwelling for spawning (Kogl 1965;Bakkala 1970;Vining et ale 1985).Selected sites were classified as either side slough,upland slough,or side channel habitats based on definitions presented in Vincent-Lang et ale (1984). 2.1.2 Surface Water Quality and Intragrave 1 Water Temperature Selected surface water quality parameters (pH,conductivity,dissolved oxygen,and temperature)were measured within each of the study sites to evaluate existing water quality conditions and determine if water quality is presently a limiting factor for salmon spawning and develop- ment at any of these sites.Measurements of each water quality para- meter were obtained at a minimum of three locations (head,mid-site,and mouth)within each study site.Measurements were obtained during non-breaching mainstem discharges at each study site to more accurately assess water quality conditions at anticipated with-project discharges. Water quality parameters were measured using a Hydrolab model 4041 water quality meter following procedu-res outlined in ADF&G (1984).Prior to each sampling trip,the meter was calibrated using procedures described in ADF&G (1984). 6 ........ Whislcu6 Crtltllc Slough~"A •RI"r MilarIOp."L.ad 1$ Figure 3.Maps of the middle Susitna River from RM 98.0 to 101.5 showing study sites and open leads. J J I I 1 !J l'J .)J i I I J ))~~ B Chase C,••k c Slough 5---... J • Sloug"6-.....~ Oxbow I--',i\.~-u •Rive,MileIaOpenLead Sl/s/rNA R/VER--- '\!)--TALKEETNA STATION A Slough ., RM 105 . Slough 3A---...........·'" Slough 38 ~ ! r r r I !'I"'"i .. !! T ! Figure 4.r1aps of the middle Susitna River from RM 101.5 to 110.5 showing study sites and open leads . ....... 8 Figure 5.Maps of the middle Susitna River from RM 110.5 to 120.5 showing study sites and open leads. Slough SA _..,. o Slough 8 Oownundo Cr••k-..I-1 o E Curry Slougn RM 120 Lo",., McKHZi.Cr••k """ - ,..", - - 9 Figure 6.Maps of the middle Susitna River from RM 120.5 to 128.5 showing study sites and open leads. •River MileBOpenLead S/~~8A G ~~Slough 9 ~~::---SIOIl911 A Sk,,11 Cr••k SlolI,h A'F RM 125 Slough 80 nlJf---Slough 88 F --CURRY STATIONE r r "f'" I i ! ! r T I 10 Slough /5 H SloliglI 98 Slough 9 G GOLD CREEK Gold CrHI (Jpper Side Channel /I H •River Mil.PlJ Open L.<fti - 1I!IIIJ'IIr, ~. Figure 7.Maps of the middle Susitna River from RM 128,5 to 137.5 showing study sites and open leads. 11 •River Wil. f!!£J Open Lead f"'" I r ! .- RMI40 Slough 168 Slough 16 Side Channel 21 ~ Water'all1--_..........Creek J Slough 21 - Figure 8.Maps of the middle Susitna River from RM 137.5 to 144.5 showing study sites and open leads. 12 K •River MileI!Open Lead _. Figure 9.Maps of the middle Susitna River from RM 144.5 to 150.0 showing study sites and open leads. 13 ,~ r j r Sampling frequency of water quality parameters varied because of logis- tics and time constraints.Originally,each site was to be sampled at least twice during the season,preferably early and late in the season. However,due to the large number of sites,lower required breaching discharges,and equipment problems,some sites were only sampled once. All data were summarized and compared with accepted tolerance ranges for spawning and incubation of sa1monid embryos presented in Appendix Table 0-1. Instantaneous intragrave1 water temperature measurements (OC)were recorded at the same time and samp1 i ng 1ocati on as for surface water quality measurements using a Digisense digital thermistor thermometer, model 8522-10 and Yellow Springs Instruments (YSI)model 419 stainless steel probe.Intragrave1 water temperature readings were taken at a depth of approximately 10 inches to reflect the approximate depth at which chum salmon eggs incubate (Vining et ale 1985).A depth of 10 inches was chosen because chum salmon were the primary species of interest and this depth allowed us to compare our data with related studies.At some locations~due to substrate composition (size or degree of cementation),the probe could not be inserted to a depth of 10 inches.In these instances,measurements were made as deep as the probe could be inserted into the substrate. 2.1.3 General Substrate Evaluations Eva 1uations of the general substrate composi ti on of each of the study sites were made by visual assessment of the dominant substrate types present throughout each study site.This evaluation was based on the substrate size classification scheme presented in Table 1. Table 1.Substrate classification scheme utilized to evaluate general substrate composition at slough and side chilnnel study sites. Substrate Code Substrate Description Size SI silt very fine SA sand fines SG small gravel iii _1'1 LG large gravel 111 _3 11 RU rubb Ie 311 _5 11 CO cobble 5"-10" BO boulder greater than 10" Substrate information was recorded on site maps to provi de a general overview of the spatial surface substrate composition of each site. Data from these general substrate evaluations were compared to accepted substrate size ranges for spawning salmonids as reported in Reiser and Bjornn (1979),Lotspei ch and Everest (1981),and Vi ncent-Lang et a 1. (1984)to provide an index as to the suitability of the substrate at each site for spawning salmon. 14 2.1.4 Upwelling and Bank Seepage Upwelling and bank seepage are critical variables that are needed to make habitat suitable for chum salmon spawning and incubation (Vincent- Lang et a.l.1984;Vining et al.1985).Upwelling and bank seepage are key environmental factors affecting survival and development of chum salmon embryos by reducing dewatering and freezing of redds and increasing the rate of exchange of water in the redds to replenish dissolved oxygen and remove metabolic wastes (Kogl 1965;Bakkala 1970; Vining et ale 1985).For these reasons,locating areas of upwelling and bank seepage was important for identifying potential mitigation sites. Areas of upwelling and bank seepage were located and mapped during foot surveys of each study site.Upwelling was usually apparent as water percolating through the substrate of a site.It was most readily apparent in areas of silt or sand where the flow of water could be easily observed as a bubbling action.In areas of substrate with little silt or sand,upwelling was observed as a current circulating through the water column if the water was calm enough and/or the upwelling strong enough.Bank seepage appeared as a lateral movement of water from the sides of a site.It was also noted where upwelling and/or bank seepage was present at high discharge but disappeared at lower discharges. Another indicator of upwelling is the presence of open leads during the winter.Aerial photos of the middle Susitna River,taken during March 1983,were used to locate open leads and verify the accuracy of upwell- ing areas documented during the summer. 2.1.5 Evaluations of Fish Passage Restrictions Baseline information on fish passage conditions were obtained from previous studies (Trihey 1982;Trihey et ale 1983;Quane et ale 1984; Sautner et al.1984;Blakely et ale 1985).These baseline data were supplemented with data from a visual inspection of the study sites to denote any fi sh passage restri cti ons due to either water depth or the presence of physical barriers such as beaver dams.Passage restrictions due to flow (i.e.depth)were primarily observed at mainstem discharges ranging from 9,000 to 12,000 cfs to determine if the passage restric- tions would be a barrier to upstream migration at anticipated project discharges.Physical barriers,primarily beaver dams,were assessed to determine their affect on upstream salmon migration.Dams at several sites were periodically opened during the peak spawning period to observe if migrating salmon would utilize available spawning habitats upstream of the dams. 2.2 Ice-Covered Studies 2.2.1 Site Selection The selection of ice-covered study sites was made to provide additional information and options that may be considered in development of the Second Interim Mitigation Report by ENTRIX,Inc.(Moulton et ale 1984). 15 ~, - ~ I ~l - - - - ~, rr,!. r J The objectives of the ice-covered season studies were:1)to provide information on additional sites as options for the present fish mitigation plan;2)to provide informati·on on potential sites for a pilot mitigation project,and 3)to provide information on potential sites that may provide additional spawning habitat for the 25%of chum salmon not addressed in the present fish mitigation plan (Moulton et a1. 1984). Three of the open-water study sites were selected·for more detailed study duri ng the ice-covered season to evaluate incubati on conditi ons and identify possible habitat modification·techniques.Study sites were selected utilizing the data collected during the open-water phase of this study.Study sites were selected to be representative of features or problems that exist in other study sites in the middle reach of the Susitna River and also have limited utilization by spawning adult chum or sockeye salmon. Sites selected for study during the ice-covered season were Bushrod Slough (RM117.9L),Curry Slough (RM119.7R),and Slough 10 (RMI33.8L). Each of these si tes presently has upw~l1 ing and only receives 1 imited use by spawning salmon.Limited numbers of chum salmon were observed spawning at all three sites during 1984. Bushrod Slough was selected as representative of sites exhibiting fish passage restrictions due to flow at the anticipated project discharges of 9,000-12,000 cfs.Curry Slough was selected as a representative study site exhibiting both substrate and passage restrictions.In addition,Curry Slough was studied as a possible fry release site in conjunction with possible incubation box development.Slough 10 is representative of sites having substrate limitations for spawning salmon. 2.2.2 Surface and Intragrave1 Water Quality Surface and intragravel water qual ity variables were monitored in each study site.Thus a comparison of the site-specific water quality variables against accepted tolerance ranges for incubating salmon (Hale 1981)will give an indication of the suitabil ity of a site for spawning and incubation.The surface and intragrave1 water quality (pH,con- ductivity,temperature,and di ssol ved oxygen)of a spawni ng area duri ng the winter is important to the incubation of salmon eggs and in the development of embryos and alevins (Vining et a1.1985).Of these four parameters,temperature and di ssol ved oxygen most di rect1y affect the rate of development,survival rate,and timing of emergence of incubat- ing salmon embryos (Vining et ale 1985). To monitor intragrave1 water quality at each study site,15 polyvinyl chloride (PVC)standpipes were placed in selected locations in each site.The PVC standpipes were virtually identical to those used in previous ADF&G studies (ADF&G 1983;Vining et a1.1985).Based on ideas presented in Terhune (1958)and Woods (1980),the standpipes·in this study were modified by placing a collar made of 1 foot by 1 foot plastic 16 (2 ml thi ck)around the base of the standpipe to reduce the flow of surface water down the outside of the standpipe (Figure 10).A collar was placed over the pipe after it was driven in the substrate and held in place with rubber bands.The collars were placed directly on the substrate with the edges being buried in the substrate.At several locations,upwelling was observed flowing up the outside of the stand- pipe after it was driven into the substrate.The flow of upvJell ing ceased once the collar was in place.It was assumed,based on the upwelling observations,that the reverse would be true in that the collars could be effective in reducing the flow of surface water down the outsi de of the standpi pe,thereby produci ng more accurate measure- ments of intragravel water quality. Instantaneous water qual ity measurements were collected periodically throughout the winter at each study site both inside and outside the standpipes using procedures described in ADF&G (1983b)and Vining et a1. (1985). A continuous record of surface and intragrave1 water temperatures was obtained using Omnidata model 2321 two channel temperature recorders (datapods)in a representative locations in each site.These tempera- ture recorders were installed and continuously operated in each winter study site fo 11 owi ng procedures in ADF&G (l983b),Kek1 ak and Quane (1985),and Keklak and Withrow (1985). - ....., - - 2.2.3 Freeze-Core Substrate Analysis Two types of substrate sampling methods were considered substrate in this study,the McNeil (McNeil and Ahnell freeze-core (Walkotten 1976;Everest et a1.1980). methods,the freeze-core technique was selected for reasons: for evaluating 1960)and the Of these two the following - 1)it allows sub-sampling of the freeze-core at varying incre- ments of depth; 2)it is more versatile,functioning under a wider variety of weather and water conditions; 3)the metal probe of the freeze-core technique provides easier penetrati on of the 1arge and cemented substrates present at many sites;and, 4)it allows more accurate sampling of sediments less than 0.062 mm (Walkotten 1976). The only change made in the freeze core system described by Wa1 kotten was the use of steel probes instead of copper.This modification was made because steel probes were more durable. Freeze core samples were collected at five locations in each of the winter study sites using a single probe freeze-core apparatus as described in Walkotten (1976)(Figure 11).The five substrate sampling 17 .... ~PVC·CAP:Prevents debris Qnd SI)OW from enter rnQpipe. PERFORATIONS:Allows inflow of intragravel water. I.Total of 48 1101.. (I/e·d lam.ter). 2.Four rinv_(12 lIol •• eSlc")of hoi...paced I (I part. CORK /WEIGHT ASSEMBLY: r r r - - •z-c...... 12"x12"PLASTIC SEAL: TEN INCHES: EXTENS ION: Aids in remoyal of ice plugs and red uces the surface area at t he air I water interface. Prevents surface water contamination during pumping of intragravel water. Estimated mean depth of chum and sockeye so Imon embryos. A 110 W S fa r s eft lin 9 if fine materials are present. Figure 10.Diagram of a polyvinyl chloride (PVC)standpipe used to evaluate intra- gravel water conditions in streambeds of salmon spawning habitats in the middle reach of the Susitna River. 18 4_2O-L &:'lUWjhlIUIiI CAAaON·OtOKIO£ 'IR[[.oINCtUIS...[Fl ~0 ~,17.0 c?Q "or:?0 . ". .0 <> Sl([l lulliNG .'7'"0.0. .12~..I,b. o ••n ''''uil NOZlLE .006"Dia~'.,Iie'_~lCaf •••lZO. C4"'."&'.1111I11II 111" 4-1/1'-M[OIUM PRtSSllRl WIR( AtiNIORC£O (;LOTH COY(R£O HOSE d NOZZLE ARRAY DETAIL . 0o.'p 0 "p <>.J>(l.Q.,.••.t?.PQ.'0 o .~,.;II,.~0 O.,.0 0,0.'"....0.'.'''','''I, .e>0 0 ,..<J (J .0 <>.'"a "''II'II ~00'0•'.0 t a.',.1 ,'(I q •I'..0'•a ,I?'.CJ,.0'G"......"II'(:I. CD I/l"~1/4 J.20 SeCk.'Heall/l Cop $u.. I.." _..I"I +--2'I ~ ~ t ".. ! liioln[ARRAY "..---0 I'll D ·0 '}.. o lJo,(J 0".'"0 II Q., d0"'0 <J":!',,'0 0 •" . ~ t> •11 a ..0 OlD It00(i'.0 ..." 'D 'Q['--1"~~r:?'pOO.0 @ "Q".t>.....0 .0 ..0 ·00. I---' 1.0 Figure II.Single probe freeze core apparatus used to sample streambed substrate in the middle reach of the Susitna River,1985 (adapted form Walkotten 1976). }•I J ~J B I i J I I J I )~)1 I I"'"" I .- ,.... locations were selected arbitrarily at each site in an attempt to represent all cha racteri st i cs present ina site.Di ffi cu 1t samp 1i ng conditions (frozen substrate,deep snow,etc.)at Curry Slough limited sample collection to two locations at this site.All freeze core samples were collected to a depth of 16 inches.This depth was selected to encompass the average redd depth for all salmon speci es (Appendix Table D-2). Through experimentation,the best substrate cores were obtained by discharging a complete 20 lb.tank of CO?into the probe for each freeze core sample.This procedure generally '""took about 10 minutes.Frozen substrate samples were then extracted from the streambed using a tripod and hand operated wi nch.Cores were thawed us i ng portable propane heaters and split into two samples,the top 8 inches and the bottom 8 inches,to observe differences in composition with depth (Everest et al. 1980;1981;Scrivener and Brownley 1981).Samples were stored in plastic garbage bags in a freezer prior to analysis. Frozen freeze core samples were taken to the Alaska Department of Transportation (ADOT)Central Materials Testing Laboratory for analysis. Sieve analysis of the samples followed procedures (T27-82 and Tll-82) outlined in the American Association of State Highway and Transportation Officials (1982).A series of seven sieves of the following mesh sizes: 127,76.2,25.4,2.0,0.84,0.50,and 0.062 mm were used in the analysis.With the exception of the 0.84 mm sieve,these are the same sizes used in previous ADF&G analyses (Vining et ala 1985).The sieve selection was based on the previous ADF&G studies as well as recommenda- tions from Wendling (1976),Shirazi et ale (1980),Lotspeich and Everest (198!),Everest et a1.(198l),and Platts et a1.1983.After sieving, the dry wei ght of each size cl ass of substrate was measured to the nearest gram and expressed as a percentage of the total weight. The quality of spawni ng gravels has traditi ana lly been estimated by determining the percentage of fine grains less than some specified diameter.Harrison (1923)and Phill ips et ala (1975)demonstrated that an inverse relationship exists between percent fines and survival. While percent fines provides an index of gravel quality,it is limited because it ignores the textural composition of the remainder of the samp 1e.Other methods,such as the use of geometri c mean di ameter of particles (Shirazi and Seim 1979),have been proposed to improve on the percent fi nes method.Used alone,each method has its drawbacks. Further research by Lotspeich and Everest (1981)and Everest et a 1. (1981)resulted in the development of a quality index that appears to overcome the 1imitati ons of other methods.Thi s qua 1ity index for gravels can be obtained by dividing geometric mean particle size by the sorting coefficient (a measure of the distribution of grain sizes)in a sample.The resulting number,called the "fredle index,"is currently being used for evaluating the reproductive potential of spawning gravel (Lotspeich and Everest 1981,Everest et a1.1981,and Platts et ale 1983). 20 The fredle index,as used in this study,incorporates the influence of texture on two fundamental properties of spawning gravels·-pore size and permeability -that influence survival.Pore size and permeability regulate intragravel water velocity and oxygen transport to incubating salmonid embryos removal of metabolic wastes,and control intragravel movement of alevins.Pore size,rather than porosity,was chosen as a component of the quality index because pore size (and permeability)is directly proportional to mean grain size while porosity has been shown to be independent of grain size.To derive the fredle index,the raw data from textural analysis was entered into a computer program devel- oped by Porter and Rogers (1984).Th is program provi des a conci se summary of the indices which describe the textural composition of spawning gravels. 2.2.4 Upwelling and Bank Seepage Because of the difficulty in observing and measuring upwelling and bank seepage,no quantitative measurements were made of either.Rather, visual observations were used to note the presence or absence of upwell- i ng and bank seepage both spati a lly and temporally throughout each of the winter study sites.If upwelling or bank seepage was not visible during the winter,the presence of an open lead in an area where upwell- ing and/or bank seepage was present during the open-water season served as an indicator of its presence during the winter.These data were then delineated on site maps with the open water upwelling observations to provide a record of upwelling patterns in slough and side channel habitats in the middle Susitna River. 2.3 Interpretation of Figures Results in this report are shown in two types of figures (box-and- whiskers plots or boxplots and scatter number plots)which warrant a description of symbols used. ~, Boxplots are IJsed to summarize water temperature,dissolved oxygen,pH, and conductivity data.The format basically follows that used by ~ Velleman and Hoaglin (1981).The boxplots,as presented here,were computer generated by the mi crocomputer program MINITAB (Ryan et a 1. 1982).Measured values (i .e.,dissolved oxygen,water temperature, etc.)from each study site comprise a data batch,which is ordered from lowest value to highest.Specific symbols used in the boxplot figures of this report are explained in Figure 12. Scatter number plots are used in a number of figures in this report to summarize water temperature,dissolved oxygen,pH,and conductivity data.Each number in a figure represents the number of occurrences in single integers (1-9)at that point. 21 **o Symbol a,b c d er + * 0 () Representative Term lower and upper hinges (about 25 percent of the way in from each end of an ordered batch) H-spread (the difference between the hinges;middle half of the data batch). minimum adjacent value =minimum observed value greater than [lower hinge -(1.5 x H-spread)] maximum adjacent value =maximum observed value less than [upper hinge +(1.5 x H-spread)] median (middle value of the batch) outside value (outside of the adjacent values) far outside value-outside of the following range: lower hinge -(3 x H-spread) upper hinge +(3 x H-spread) notches (represent approximately a 95 percent confidence limit about the median): median ±1.58 x (H-spread)/-v7i r-Figure 12.Definitions of symbols used in boxplots which summarize water temperature,dissolved oxygen,pH,and conductivity data. -22 -. r I 3.0 RESULTS 3.1 Open-Water Studies Results of open-water studies conducted at 44 potential mitigation sites in the middle reach of the Susitna River from July 31 .to October 8,1984 are presented in the following sections.Of the 44 sites identified,23 were side sloughs,16 were upland sloughs,and 5 were side channel habitats.A summary of the selected site characteristics for each of these sites is presented in Table 2. 3.1.1 Instantaneous Surface Water Quality and Intragravel Water Temperature Data Instantaneous surface water qual ity and intragravel water temperature measurements recorded at all slol\gh and side channel sites during the open water sampling period are presented in Appendix Table B-1.A comparison of the range and mean of water quality parameters measured in side slough,upland slough,and side channel habitats by sampling period is presented in Figure 13 and Figure 14.Because of the limited number of samples that were collected,only general assumptions can be made regard"jng differences in water quality between sites.A comparison of the mean water quality parameters over time i ndi ca te that there were no major differences between the three habitat types and that water quality is not presently a limiting factor for salmon spawning and development at any of these sites. 3.1.2 General Substrate Evaluations Substrate composition of slough and side channel study sites,as deter- mined from visual observations,is presented on individual site maps in Appendix A.Side slough habitats tended to have a greater percentage of loose gravel substrates,whereas the substrate composition in side channels was more compacted and generally contained more rubble,cobble, and boul der.Upl and sloughs generally have a greater percentage and depth of silt-sand deposits compared to side sloughs. 3~1.3 Upwelling and Bank Seepage Prior to the open-water season,winter aerial photos of open leads in the ice were studied to try to identify upwelling and bank seepage at prospective study sites.During the open-water season,areas where open leads had been present on winter aerial photographs were checked and all observations of upwelling and bank seepage at side slough,upland slough,and side channel habitats were recorded on site maps (Appendix A).Upwelling and bank seepage are also discussed on a site by site basis in the site description narratives in AppendiX A.Sites where upwelling and/or bank seepage has been recorded are summarized in Table 2. Of the 23 side sloughs surveyed,18 (78%)exhibited upwelling and/or bank seepage.Fourteen (61%)of the side sloughs surveyed,had open 23 ~l, DRAFT /PAGE 1 8/26/85,8/29/85 37TABlTable 9 ~'i Table 2.Summary of selected site characteristics of potential mitigation sites surveyed in the middle reach of the Susitna River,1984. ~ Upwell ing Passage Salmon Open Bank Restrictions -Rivef Habit~t Spawning 3 Lead Seepage Beaver 4 due Site Mile Type Observed Observed Observed Activity to Beavers 5 Slough 99.5R US X X Slough 2 100.7R SS X X X X Whi skers ~ Creek Slough 101.2L SS X X X X X Slough 3B 101.4L SS X X Slough 3A 101.9L US X X X X X Slough 4 105.2R US X X Slough 5 107.6L US X X X X Slough 6 108.2L US X X X Oxbow I 110.1L SC X X ~l, Slough 6A 112.3L US X X X Slough 7 113.2R SS X ~ Slough 8 113.7R SS X X X Mainstem 2 114.5R SC X X X Bushrod Slough 117.9L SS X X X Curry ~ Slough 119.7R US X X X Slough 80 121.8R US X X X Slough 8e 121.8R SS X X - Slough 88 122.2R SS X X X Moose Slough 123.1 R SS X X ~ Slough A'124.6R SS X X Slough A 124.8R US X X Slough 8A 125.3R SS X X X X X Slough 8 126.3R SS X X ~ Slough 9 128.3R SS X X X Slough 98 129.2R US X X X X X Slough 9A 133.2R SS X X X X Slough 10 133.8L US X X X X X 24 ~, Table 2 (Continued). DRAFT/PACE 2 8/26/85,8/29/85 37TABITable 9 Upwelling Passage Salmon Open Bank Restrictions Rive~Habit~t Spawning 3 Lead Seepage Beaver 4 due 5 Site Mile Type Observed Observed Observed Activity to Beavers Side Channel 10 133.8L SC X X Slough 11 135.3R SS X X X .-Slough 12 135.4R US X X Slough 13 135.5R 55 X X Upper Side Channel 11 136.0R SC X X X Slough 14 136.0L US X X X X Slough 15 137.2L 55 X X X X Slough 16 137.7L 55 X X Slough 16B 137.9L 55 X X Slough 17 138.9L US X X X X X Slough 18 139.1 L US X X.-!Slough 19 139.8R US X X X X Slough 20 140.1 R 55 X X-Side I Channel 21 140.6R SC X X X Slough 21 141.8R 55 X X XrSlough22144.2L 55 X X X Slough 21A 145.3R SS X X Letters idicate left bank (L),right bank (R)or center channel (C)as viewed looking upstream r 2 55 -side slough 'I US -upland slough I SC -side channel 3 Spawning observed at least once during 1981-1984.Appendix Table C-1 presents a morerdetailedpresentationofspawningobservations. 4 Beaver activity refers to either a lodge,dam or both. 5 All sites may have passage restrictions due to flow in the 9,000 to 12,000 cfs range. 25 N O'a I""".""LIMIT ISIDE SLOUGHS I I UPLAND SLOUGHS I MEDIAN 15-15 -~LOWER RANGE-LIMIT0 !..~ ....ISIDE CHANNELS I0:: :)10 to I 10- ....!;(-I00::I<w U-Q.. IO::::E :).....'4 J:(I)/-5-_L 5 5 .'33 -0::.'38 .'3 W .-;;2~.'6 !;(nl:14 ~_L .'6~n"40 '"...'"0 7/~1.8/11 1 .30 9/IL3 0 7/~"8/11.30 9/11.13 10)1.8 0 d,.8/IL30 911',.,3 10)..810/1·8 8/11 8/~8/11 15-15- 0 '"NO SAMPLING .CONDUCTED !..~DUE TO 8REACHED CONDITIONS ~....~ ..J~10 10-10-WI->.q J <0:: I0::....I I(!)Q.. c(::E O::w II-I-5 5 5- Z n;:6 •-0::n=a .'7 W -."0 L n:29 I-.'2~n'6~n.'39<n-3' ~ 0 0 '"'">If I 8/IL 30 9/IL 13 lol8 0 7/~'.8/IL30 I ! 7AI-8/1:.30 10A.87/31-9/11-13 10/1.8 9/11-13 8/~8/5 8/~ 1984 SAMPLING PERIODS Figure 13.Comparison of the range and mean of instantaneous surface water and intragravel water temperatures measured at side slough,upland slough,and side channel habitats by sampling period,1984. ,1 J ,,.J ~j J J .~1 .~~J )J 9 - 10·I n=t4 I UP...PER_.RAHGE. ~IM'T MEDIAN ~OWER RANGE ~IMIT ISIDE ~HANNELS I - - ,.,,.,,., o .J..."";---";---"'1Ir--,.....\-TAI-B/1I 1 -30 9/11-13 10/1-8 8/5 10- 20 - ,.,NO SAMPLING CONDUCTED DUE TO BREACHED CONDITIONS IUPLAND SLOUGHS I - I I I .'38 .'5 .,l;jo o .J..-:;7/"I'.~:':'_--8/":'tT"!1.-30-9-/"1',1--'-:5-IO.:l:/Tt-~8­ 8/5 10 20 ISIDE SLOUGHS I - I .':53o....L.._";'--.,...---r--r---.IT ,I I 7/31.8/11-:50'9/11-1:5 10/1-B 8/5 20- I :..L_;...'3""3__!-T2_5_....,~r"'3__~T'4_3_I :-..J.._J.,.'38 ~r-6__;re..,.,_3__n!-r3_7_]-""'~---*T"i__,~"!-,..~.__ .!.8;'~-30 9/M-13 10/1-8 7/3.-8/11-30 9/11-13 10/1-8 7/31-8/H-30 9/11-13 10/'-8T'~~_8/5 8/5 O..J..--,~-~--",--,~­TAI-8/11-30 9/1t-13 10/1-8 8/5 100- ,.,,.,,., o ...L-':-I--T"-_·Ir---"""- 7/3.-B/II -30 9/U-13 10/1-B 8/5 lOa 300 -,-200 -'-.'40 I ,,:.6 -,-- . 200 -,..300- I n :.4 -'-.1.-o..L_....'''"33_-Ll:.'~5 __r--_...,.__ rAI-8/11-30 9/J-13 lO/I-B 8/5 -300-Eu..... a:~ u,js: I-E;.=200 \lJ~o.!: ~~a:I- ~o (/)~100- Zoo • r I 1984 SAMPLING PERIODS Figure 14.Comparison of the range and mean of dissolved oxygen,conductivity,and pH measured at side slough,upland slough,and side channel habitats by sampling period,1934. 27 leads during the winter,which we attribute to upwelling.However, upwelling was not documented at all side sloughs that had open leads. Five side sloughs that had no visible upwell ing (3B,8B,16,16B,and 20),had open leads during the winter,indicating that upwelling may be present rven though not visible.Also,eight side sloughs (7,8C, Moose,A ,B,13, 15,and 21A)that exhibited upwelling and/or bank seepage,had no open leads during the winter. Upwelling was observed in a smaller percentage of upland slough habitats than was observed in side slough habitats.Upwelling and/or bank seepage was observed in seven (44%)of the 16 upland sloughs surveyed. Open leads,an indication of upwelling during the winter,were observed in 11 (69%)of the sites.The only upland slough site that had upwe ll"j ng but no open 1ead was Slough A.Upwell i ng may be present in the four sites that had open leads even though none was observed during the open-water surveys. Upwelling was observed in 4 of the 5 side channel habitats surveyed during 1984.Only Oxbow I Side Channel had no visible upwelling or bank seepage.All 5 side channels did have open leads during the winter, indicating the possible presence of upwelling in Oxbow I Side Channel. Although upwelling was found at side channel sites,it did not appear to be as strong or extensive as the upwelling found in side slough habi- tats. 3.1.4 Evaluations of Fish Passage Restrictions Fish passage restrictions in side slough,upland slough,and side channel habitats can result from restricted flows or physical barriers. Flow related passage restrictions in selected sites have been previously discussed in Trihey (1982),Trihey et ale (1983),Sautner et ale (1984), and Blakely et ale (1985).Field observations indicate that in the 9,000 to 12,000 cfs range,all of the open-water season study sites will likely have flow related passage restrictions.No further detailed analysis of flow-related passage restrictions other than field obser- vations was done for this study.Results of the passage portion of this study focus on physical barriers,primarily beaver dams,that may be easily removed for mitigation purposes.Beaver dams may be barriers to the upstream migration of salmon (Canada 1980).Sites having potential fish passage problems due to beaver activity are summarized in Table 2. Of the 23 side sloughs surveyed,six (26%)have beaver activity.Of these sites,only two (Sloughs 8A and 15)presently have passage restrictions due to physical barriers resulting from beaver dams.The other four sites (Sloughs 2,Whiskers,88,and 9A)have beaver activity associated with them but no passage barriers at present.However,it appeared as if several dams were being constructed in the fall of 1984 at Slough 2.Completion of these dams will likely result in physical barriers to fish passage. 28 r- Il r r " r- I Beaver dams which were opened at two side slough sites during 1984 resulted in successful passage of salmon to areas upstream of the dams. In Slough 8A,a beaver dam constructed duri ng 1983 i so 1ated all previ- 0usly utilized spawning area upstream of it.During 1984,several dams in Slough 8A were periodically opened to determine if providing passage through the dams would be a poss"ible mitigation alternative.When the dams were opened,the chum,sockeye,and pink salmon that were present, readily migrated through the opening in the dam and utilized the avail- able spawning habitat upstream of the dam.A similar situation occurred on Whiskers Creek,emptying into Whiskers Slough.In this case,coho salmon readily migrated through the dam to upstream spawning areas. Beavers are present in 14 (88%)of the upland sloughs surveyed.Beaver dams prevent passage of salmon in eleven (69%)of the upland sloughs surveyed.Three upland slough sites (Slough 1,80,and 19)have beaver activity,but no dams at present. Beaver dams in selected upland slough sites were opened to see if chum salmon would utilize newly available or previously utilized spawning habitat.Slough 4 was opened but no adults entered the area above the dam.Due to lack of upwelling and thick silt deposits the newly acces- sible area was probably unsuitable as a spawning site this year.The dams in Slough 9B were periodically opened to see if chum and sockeye salmon would spawn in a previously utilized area.Both species spawned in Slough 98 prior to the construction of the dams in late 1982.The fish.that enter Slough 9B must travel through Slough 9 to reach the mouth.During a high water period,passage was possible through Slough 9 and chum and sockeye salmon readily migrated into the slough.They selected upwelling areas for spawning and removed thick silt deposits, up to 18 inches,to reach the spawning substrate. At present all passage restrictions located in side channel habitats are flow related.Wh il e consi derab 1e si te-by-si te variation exi sts,side channels dewater appreciably at low mainstem discharges,creating numerous passage restrictions.Backwater affects will influence passage reaches in the mouth a rea of side channe 1s but genera 11 y not those upstream.No beaver activity was observed in any of the side channels surveyed. 3.1.5 Salmon Spawning Utilization The locations of side slough,upland slough,and side channel habitats which have been utilized by spawning salmon in the middle reach of the Susitna River between 1981 and 1984 are shown on individual site maps in Appendix A.SIJmmary tables of salmon spawning data at individual sites are presented in Table 2 and Appendix Table C-l. In the middle reach of the Susitna River,side slough habitats are primarily used as spawning areas by chum and sockeye salmon and less frequently by pink salmon.Although chum and sockeye salmon spawn in many different side sloughs in the middle reach,the sites which have 29 consistently had the highest concentrations of spawners are Sloughs 8A, 9,11,and 21.Pink salmon have been observed spawning in 15 of the 23 side slough sites.They have frequently been observed in other sites but only as milling fish.During the period 1981-1984,the only side slough in which salmon spawning or milling was not reported was Slough 7. Chum and sockeye salmon are the predominate species which utilize upland sloughs for spawning.Of the 16 upland sloughs studied,salmon spawning has occurred at 12 (75%)of the sites during one or more years in the 1981-1984 time period.Sloughs 1,5,Curry,and 14 had spawning reported for the first time in 1984.Only two upland sloughs (l7 and 19)have had spawning reported in every year.Four of the sixteen upland sloughs studied (Sloughs 4,6,6A and 12)had no reported salmon spawni ng duri ng 1981-1984.These four sloughs have extensive beaver activity and limited spawning area.It should be noted that even though 75%of the upland sloughs have had spawning reported during 1981-1984, only a few have had spawning every year.In addition,because the spawning area is limited in upland sloughs the numbers of fish spawning in upland sloughs is relatively low and their overall contribution to the fishery is low. Of the 5 side channels surveyed,only Side Channel 10 has no reported salmon spawning.Three milling chum salmon were observed in Side Channel 10 during 1984.Oxbow I had limited chum salmon spawning reported in 1984.The remaining three sites (Mainstem 2,Upper Side Channel 11,and Side Channel 21)have had chum salmon spawning every year between 1981 and 1984.Sockeye and pink salmon have al so been observed spawning in Upper Side Channel 11 and Side Channel 21.Coho salmon have been observed milling in Upper Side Channel 11 every year, but have not been observed spawning.Chinook salmon have not been observed in side channel habitats. 3.2 Ice Covered Surveys Based on the results of the open water surveys three sites were selected for more detailed study to better determine their potential as possible mitigation sites.These studies included an examination of incubation conditions at each site and identification of selected habitat modifica- tion techniques that may be used as mitigation alternatives at these sites.The three sites selected,Bushrod Slough (RM 117 .9L),Curry Slough (Rl~119.7R),and Slough 10 (RM 133.8L)presently have limited salmon spawning activity that may be due to factors such as passage restrictions,substrate limitations,or lack of upwelling. 3.2.1 Physical Characteristics 3.2.1.1 Water Temperature Water temperature data presented in this section includes instantaneous surface and intragravel water temperatures measured at individual standpipe water quality sampling sites,and continuous surface and intragravel water temperatures measured at each mitigation study site. 30 l!!!iI1'W;' - - [ I 3.2.1.1.1 Instantaneous Surface and Intragrave1 Water Temperature A comparison of instantaneous surface and intragrave1 water temperatures measured at standpipes in each slough are presented in Figure 15.The raw data used to develop these figures is presented in Appendix Table E-1.There is a general relationship between winter surface and intragrave1 water temperatures.Thi s re 1ati onshi pis more evident at Curry Slough than at Slough 10.This is unexpected since Slough 10 has a greater amount of upwell ing and the surface and intragrave1 water temperature ranges are most similar. A summary of surface and intragrave1 instantaneous water temperatures for these three sites is presented in Figures 16 and 17.For all three sites,the median values for intragrave1 water temperatures are higher than for surface water temperatures.Bushrod Slough has the hi ghest median intragrave1 water temperature and Curry Slough the lowest. Slough 10 has the highest median surface water temperature and Curry Slough the lowest. 3.2.1.1.2 Continuous Surface and Intragrave1 Water Temperature Continuous surface and intragrave1 water temperatures were measured at one location in Bushrod and Curry Sloughs and in two locations (one site in each channel)in Slough 10 (Figures 18,19,20,and 21 respectjve1y). A complete presentation of these data are included in Kek1ak and Withrow (1985).Bushrod and Curry Sloughs experienced a drop in temperatures until early November with surface water warmer than intragrave1 water. After thi s time,water temperatures warmed sl i ght1y with i ntragrave 1 temperatures warmer than surface water.In Slough 10,the decrease in water temperature lasted until early December with intragrave1 water temperatures becoming warmer than surface water in early November.The northeast channel in Slough 10 exhibited more variability in both surface and intragrave1 water temperatures than was found in the other sites.The ranges of conti nuous water temperatures,whil e comparable to the instantaneous data,present a more complete record and better describe the variability of water temperatures in each site. 3.2.1.2 Freeze Core Substrate Analysis Freeze-core substrate samples collected at Bushrod Slough,Curry Slough, and Slough 10 were analyzed to compute a fred1e index.The fred1e index is a measure of substrate quality in terms of both pore size and rela- tive permeability,both of which increase as the fred1e index increases. This textural analysis verifies the general visual substrate evaluations made during the open-water survey period.The composition of substrate samples collected at these three sites are summarized in Appendix Table F-l. For all substrate sa~p1es obtained in Bushrod Slough,the greatest size percentage,by weight,of substrates felT within the 2.0 mm to 127 mm size class.Only one sample contained particles greater than 127 mm in size.All samples contained some fines less than 0.5 mm in size, whereas only two samples (4A and 2B)contained (34%and 38%respec- tively)fines of this size class. 31 BUSHROD SLOUGH ...---------...---------...---------~...--------...---------+----_._---... 5.00+~: CURRY SLOUGH 5.00+<!"---------+---------+---------..---------+-----_.---+-------.,.-+ SLOUGH 10 4.5B~ Ii 4.17~,EI t.. 3.1'~W W II: II:I I :> :>~.:SJ~l- I-~ ~ 1 '11 II: II:,W W 2.92~"- "-I I I I :I:I w W 2.50~I,l- I-I I ,2 I II: II:W W ,I l- I-2.08·I I ~ ~I ~~- -' -'1.b7~W W >>,~ ~II: II:I.:;!!l ..0 0 ~ ~II: II:l- I-.OJ·n·1I0 z !--w I r .0.11 N ..~~p <0.001 -i.:iiB~ 4.17+ 3.7:5. 3.3J,+ 2.92~ 2.:50+ 2.0B+ 1.67'" 1.2:5+ .e3~1 .42~ II 1.2 I, n ·3'r •0.82 P <0.001 4.58+ ~4,J7; W 3.7~~II::> I-J,.:n~~ II:w "-2.¥2~:I W l- ll:2.:;0; W -I--~2.08;~~ .... W l.b7.>-~ II: 0 1.2:5.-~-11:. -l-•!.8:1+ •"2~ I , Il:I \J ~lll ~,,!.1, ~IF I III'2 I I!I 11 n·73 r •0.47 P <0.001 •00+++_......+....+++... .00 .93 1.607 2.:50 3.33 4.17 5.00 SURFACE WATER TEMPERATURE I'C) .00.+---------.------~~-+---------+---------..---------+---------+.00 .8J 1."7 2.:50 l.J3 4.11 5.00 SURFACE WATER TEMPERATURE I'C) .00++++..~,...----0.+... .00 .83 n.b7 2.50 3.33 4.17 :5.00 SURFACE WATER TEMPERATURE I'Cl Fi gure 15.A comparison of instantaneous surface and intragravel water temperature (DC)data measured at standpipes in Bushrod Slough~Curry Slough~and Slough 10 during the ice-covered season~1984-85. I }I l ~)).t ,"7'5 ,I J .~J I t ~,.1 -;ljd •0 BUSHROD SLOUGH Q •LOIil'£1Il !'lING!: b·UP9i[fI "IMG( C'1'IB'PR£Al) d'.lfiIlIIllU,...lOJAC.[HT VAl.-l,IE ~....IltlUlIf &1)"...·(.£N1 VII\.U£ ...."IEDI ..,. I ~.'~'"Jl.C.L "'80UT nu: M£DI4H ...OUfSID€VALVE O~rAI'I'OUTSIDE ......LUE j-----(----------- --------------------------------------------~------------~-)--------------------- ----------~---------------1 [t j------}---------------------------._-_.....---- -----------------I (~\----1------------- r NOVEMBER 29,1984 (n =13) JANUARY 8,1985 (n=I2) JANUARY 30,1985 (n =Ill CURRY SLOUGH 0.4 I 0.8 I 1.6 T 2.0 , 2.4 T 2.8 4~O NOVEMBER 28,1984 -----------I------(-~----------~-----------I {n =14}---------------------------- - --)-------------------- JANl,IARY 9,1985 (n=lI) --------------(-I +)1-----------* -----(1 ~)1-------- r Ii" rI SLOUGH 10 NOVEMBER 14,1984 (n =4) NOVEMBER 27,1984 (n=15) T 0.4 I 0.8 , 1.2 I 1.6 -I I 2.0 t I 2.4 I 2.8 \--)---- I 3.2 I 3.6 4~0 1 4.4 DECEMBER I I,1984 (n=15) JANUARY 10,1985 (n=15) ---I t 1----)--- *------I (t--)-- ----I (tH-- -----------1 ()--------------------- FEBRUARY 1,1985 (n =15) APRIL 2,1985 (n =15) T 0.4 I 0.8 I 1.2 I 1.6 I 2.0 I 2.4 * + I 2.8 I 3.2 I ~.6 I 4.0 I 4.4 SURFACE WATER TEMPERATURE (OC) Figure 16.Summary of instantaneous surface water temperature data (OC)measured at standpipes in the middle reach of the Susitna River,by study site and sampling period,ice-covered season 1984-85. 33 • Q BUSHROD SLOUGH Q.LOW[1ll I·UNGE: b D UP9[1It MINGlE e.N_SPREAD d."'PolIIllUM i.OJACiEMT VALUE: t'••"!Ct"UM AO......C[NT VALUE -to "(DIAN I ,-'U""C.l."flOUT THE IIIrOIA.. "·ourSID[W61-U[ O.,..aft ouTStOE ......LYE NOVEMBER 29,1984 (n =9) JANUARY 8,1985 (n=IO) ---------(1 -·(--1 + )1--------- J 1--------------- JANUARY 30,1985 (n=lI) -------1 (t J -------- 0.8 1.2 I 1.6 I 2.0 I 2.4 I 2.8 I 3.2 T 3.6 T 4.0 4~8 CURRY SLOUGH NOVEMBER 28,1984 (n :;8) -----------(-------(+I 1------- ,.."" JANUARY 9,1985 (n=11) --(---I +1----------- 0.8 SLOUGH 10 r 2.0 1 2.4 2.8 I 3.2 1 3.6 I 4.0 1 4.4 I 4.8 NOVEMBER 14,1984 (n =3) ---------(-1 +1-- NOVEMBER 27,1984 (n=15) DECEMBER I I,1984 (n=12) -------(----1 to ---------(----1 t 1-------- 1------ JANUARY 10,1985 (n =151 --------1 (+t-l---- -----_(_l +)1---- ----,( +1)-------_.._--- FEBRUARY 1,1985 (n=14) APRIL 2,1985 (n=14) 0.8 * r 1.2 I 1.6 I 2.0 I 2.4 r 2.8 I 3.2 I 3.6 I I 4.0 4.4 I 4.8 - INTRAGRAVEL WATER TEMPERATURE (OC) Figure 17.Summary of instantaneous intragravel water temperature data (OC)measured at standpipes in the middle reach of the Susitna River,by study site and sampling period,ice-covered season 1984-85. 34 BUSHROO SLOUGH (RM 117.9) --MEAN DAILY INTRAGR"'VEL -----MEAN DAILY SURFACE .......TER , ()I ~,...,--- <>" ",__""_1 ....--...__ ___1-____-~,,.1-_---.,W ,{-'Ia:-,-./..."~.- <l:a: Wa.. ~w.- cr:-I W.--.<l: 3: -3 -i -5 . SEP OCT NOV DEC JAN FEB MAR APR MAY Figure 18.t4ean daily intragravel and surface water temperatures ("C) recorded at Bushrod Slough (RM 117.9)during the ice- covered season,1984-85. r I CURRY SLOUGH (RM 119.7) --WEAN DAILY INTRAGRAVEL -----"'EAN OAILY SURFACE WATER -....._.-MEAN DAILY SURFACE FROZEN Mean daily intragravel and surface water temperatures (~C) recorded at Curry Slough (RM 119.7)during the ice- covered season,1984-85. () <> W J a: ~.-2«a: w 1 a.. :Ew a.- a:-I W.--2<l: 3: -3 -i «--5 ,j SEP OCT Figure 19. .~ \I ~ NOV DEC JAN FEB MAR APR MAY 35___________________------__.-1 SLOUGH 10 NORTHEAST (RM 133.e) --MEAN DAILY INTRAGRAVEL -----MEAN DAILY SURFACE WATER 5 _. lJJ J 0: :::lI-2 et 0: lJJ I 0... ~ lJJ I- 0:-I W I--2et:= U io -3 -5 SEP OCT NOV DEC JAN FEB MAR APR MAY Figure 20.Mean daily intragravel and surface water temperatures (dC) recorded at Slough 10 Northease (RM 113.8)during the ice- covered season.1984-85. SLOUGH 10 NORTHWEST (RM 133.eJ --WEAN DAILY INTRAGRAVEL -----WEAN DAILY SURFACE WATER U o UJ J 0: :::l I-2et 0: UJ 1 0... ::E UJ a I- t \, _,-....~...,,'\._J ...--~,..\,_"_"......t ....,, \"",-~"..._,,- \..._-....' ~i 0:-1 lJJ I-et -2 := -3 -5 SEP OCT NOV DEC JAN FEB MAR APR MAY Figure 21.Mean daily intragravel and surface water temperatures (OC) recorded at Slough 10 Northwest (RM 133.8)during the ice- covered season,1984-85. 36 - 1"""" I - -I A summary of the computed i ndi ces of substrate quality.for Bushrod Slough is pres'ented in Table 3.For the.total sample,Bushrod Slough. had a fredle index of about 12.07 with 11.8%of the sample finer than 1.0 mm.The upper eight inches of the samples have a fredle index of about 15.16 with 13.0%finer than 1.0 mm.The lower eight inches of the samples has a fredle index of about 11.13 with 14.8%finer than 1.0 mm. These results i ndi cate that the substrate in Bushrod Slough is of good quality for salmon spawning.However,substrate quality could be improved by removing fines which accumulate in the lower eight inches of the streambed. Numerous problems were associated with the collection of freeze core samples at Curry Slough.As a result,only two samples were obtained, one each at opposite ends of the main pool.The size composition of the majority of the substrate obtained was between 2.0 mm and 127 mID.The furthest upstream site contained a greater percentage of fine material less than 0.5 mm (Appendix Table F-1).The affect of the fines can be seen in the lower intragravel dissolved oxygen readings at standpipes in thi s area. Due to the limited number of samples obtained at Curry Slough no analy- sis of substrate by depth was conducted.Table 4 summarizes the com- puted quality indices for Curry Slough.The fredle index is about 7.16 with 17.1%finer than 1.0 mnJ.These numbers indicate that the quality of s.pawning substrate is.not as good as is.found in other sites,such as Bushrod Slough,due to a higher percentage of fines. In Slough 10,substrate composition shows a preponderance of unsuitable spawning substrate at those sites which were sampled (Appendix Table F-1).The majority of substrate samples collected are less than 0.5 mm in diameter.An exception is sample five,taken in the area where salmon currently spawn.This sample contained very few fines with 78% of the total sample being greater than 127 mm,largely cobble and boulder. The overall substrate analysis of Slough 10 results in a fredle index of about 18.46 indicating good spawning substrate (Table 5).This index is somewhat misleading because only one sample from the presently used spawning area,contains suitable spawning substrate (AppendiX Table F-1).This sample appears to have strongly influenced the fredle index. The large percent of fines less than 1.0 mm in size (78.6%)recorded at this site should result in a smaller fredle index reflecting the appar- ent poor quality of the spawning substrate.The relatively large geometric mean (27.61)and small sorting coefficient (2.46)appear to be the modifying measurements resulting in the larger fredle index.These two numbers indicate that the sample has large pore spaces that are not completely filled with fines,allowing for intragravel flow and movement of alevins.When the freeze core is divided into two subsamples,this same result is evident,especially in the upper eight inch subsample. The analysis subdividing the freeze core samples in Slough 10,illus- trates a decrease in substrate quality with depth.The upper eight inch subsample has afredle index of about 26.52 with 78.9%finer than 1.0 mm.The lower eight inch subsample has a fredle index of about 0.61 37 Table 3.Summary of computed substrate quality indices at Bushrod Slough (RM 117.9L) Mean Total Sample Standard Error of Mean Sample Size Total Sample Weight (g) Geometric Mean Particle Size (mm) Sorting Coefficient Fredle Index Percent Finer Than 1.0 mm Total Sample Weight Geometric Mean Sorting Coefficient Fredle Index Percent Finer Than 1.0 mm Total Sample Weight Geometric Mean Sorting Coefficient Fredle Index Percent Finer Than 1.0 mm 1438.94 25.56 2.62 12.07 11.77 Upper 8"Subsample 804.38 31.28 3.20 15.16 13.02 Lower 8"Subsample 634.56 21.86 3.30 11.13 14.78 291 .48 5 6.81 5 0.40 5 4.36 5 3.26 5 ~ 179.32 5 10.23 5 1.04 5 5.28 5 6.17 5 - Table 4.Summary of computed substrate quality indices at Curry Slough (RM 119.7R) Total Sample Weight Geometric Mean Sorting Coefficient Fredle Index Percent Finer Than 1.0 mm Mean Total Sample 1216.45 19.27 3.90 7.16 17.06 38 Standard Error of Mean 711.65 7.75 1.70 5.11 6.70 Sample Size 2 2 2 2 2 - Table 5.Summary of computed substrate quality indices at Slough 10 (RM 133.8L). - -r-' ! l r Total Sample Weight Geometric Mean Sorting Coefficient Fredle Index Percent Finer Than 1.0 mm Total Sample Weight Geometric Mean Sorting Coefficient Fredle Index Percent Finer Than 1.0 mm Total Sample Weight Geometric Mean Sorting Coefficient Fredle Index Percent Finer Than 1.0 mm Mean Total Sample 212.92 27.61 2.46 18.46 78.56 Upper 8"Subsample 186.34 36.91 2.35 26.52 78.98 Lower 8"Subsample 26.58 2.14 3.28 0.61 77 .34 39 Standard Error of Mean 160.67 27.46 0.33 18.41 18.92 145.77 36.75 0.35 26.45 19.41 14.98 2.00 0.30 0.56 15.70 Sample Size 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 wi th 77.3%fi ner than 1.0 mm.One of the primary reasons for such a di fference in the fred1 e index between the two samples is the 1a rge difference in geometric means;36.91 for the upper eight inches as compared to 2.14 for the lower eight inches. 3.2.1.3 Upwelling and Bank Seepage Areas of upwelling and bank seepage are recorded on individual site maps for Bushrod Slough,Curry Slough,and Slough 10 in Appendix A (Appendix Figures A-31,A-35 and A-74,respectively).Upwelling and bank seepage are also discussed in the individual site description narratives in Appendix A. The lower pool in Bushrod Slough,where the majority of salmon spawning occurred,had visible bank seepage occurring along the left bank during the open-water season.Due to the clean gravel and clear deep water no other upwelling was visible in this pool.This bank seepage ceased to flow with the onset of winter.Most of the spawning occurred along the right bank.In addition,an open lead occurred along this bank indicat- ing that upwelling continued at this site during the winter. The upper po01 of Bushrod Slough,which supported no spawning,had only 1imited bank seepage along the ri ght bank duri ng the open-water season which appeared to be related to mainstem flows.As the mainstem dis- charges dropped in the fa 11 ,this seepage slowed and then stopped. Consequently,the upper poo1 dewatered completely and the substrate froze.No open leads were observed in this section of the slough. Curry Slough primarily consists of two pools separated by a riffle.The water level in the lower pool appears to be related to mainstem flows, creating a backwater at higher discharges.As the mainstem dropped in the fall,this pool dewatered and froze.No upwelling or bank seepage was observed in this po01 during the open-water or ice-covered season. The upper pool has limited upwelling and bank seepage in the lower half, during the open-water season,which was not readily apparent during the winter.The upper haH of the pool,as well as the riffle separating the head of the po01 and the berm at the head,contains the majority of the upwelling and bank seepage.Both upwelling and bank seepage in this area are strong and constant throughout the wi nter.An open 1ead was present throughout this area except during the extreme cold experienced in February.Bank seepage in other areas of the slough appears to be intermittent and more dependent on surface runoff than true groundwater. Upwelling and bank seepage were present throughout Slough 10 during the entire year.The upwelling provides a stab1e incubation environment as well as keeping the slough ice free.This slough appears to have one of the stronger and more continuous upwellings found in the middle reach of the Susitna River. 3.2.2 Chemica1 Characteristics 3.2.2.1 Dissolved Oxygen Comparisons of dissolved oxygen concentrations (mg/l)measured in surface and i ntragrave1 water in standpi pes in Bushrod Slough,Curry 40 - ~, - ..... '""" - - Slough,and Slough 10 are presented in Figure 22.Similar plots for percent oxygen saturation can be found in Figure 23.The raw data used to construct these plots is presented in Appendix Table E-1.The relationship between surface and intragravel dissolved oxygen levels, indicating an influence of intragravel water and surface water,appears to be strongest in Bushrod Slough and weakest in Slough 10.A weaker relationship (i.e.,wider scatter of points)appears at Curry Slough and Slough 10 at low and intermediate measurements than at higher measure- ments.Median dissolved oxygen values for both surface and intragravel water are lowest in Slough 10 (Figures 24 through 27).Bushrod Slough has the highest median intragravel dissolved oxygen concentration,while Curry Slough has the highest median surface dissolved oxygen concen- tration.However,due to the dewatering and freezing which occurred in the lower section of Curry Slough the accuracy of the intragravel water measurements from the fi rst three standpi pes are suspect.There is a strong probabi 1ity that surface water i nfl uenced the di ssol ved oxygen measurements in this section of Curry Slough. 3.2.2.2 .Eli Comparison of pH levels measured in surface and intragravel waters in Bushrod Slough,Curry Slough,and Slough 10 are presented in Figure 28. Because of sampling problems,the number of pH measurements at Bushrod and Curry Sloughs is approximately half the number obtained at Slough 10.The figures show that there is a relationship,indicating an influence of intragravel water and surface water,between pH values measured in surface and intragravel waters.The relationship appears strongest in Slough 10 and weakest in Curry Slough.Slough 10 has the highest median pH readings for both surface and intragravel water and Curry Slough the lowest (Figure 29 and 30). 3.2.2.3 Conductivity Scatter plots of the conductivity levels (umhos/cm)in surface and intragravel water in Bushrod Slough,Curry Slough,and Slough 10 are presented in Figure 31.The relationship between surface and intragravel conductivity levels,indicating an influence of intragravel water and surface water,appears strongest (i.e.,closer scatter of points)in Bushrod Slough and Slough 10,and weakest (i .e.,wider scatter of points)at Curry Slough.In both surface and intragravel waters,Slough 10 has the hi ghest median conductivity val ue and Curry Slough the lowest (Figure 32 and 33). 41 BUSHROD SLOUGH CURRY SLOUGH SLOUGH 10 15.00+-+---------+----...----+---------+---------..---------..---------...+I:'.OO~+---------+---------+------...-.-------...-------+---------+ U.715~ 00+++----~----+--------+---------+---------..---------+---------+.00 2.:50 3.00 1.50 10.00 t2.~1:5.00 '. -,- .0Qt-+++"'++~__~__....., .00 2.'5Q ~.Oo 7.50 10.00 12.:'0 1:'.00 21 II , 1 1'1"'1'I, I P I~1 I 121 !t • I I U f 2 II I _i!"I I _ •QQ+...---------+---------+---.,.-----+---------...---------+---------++ .00 2.50 S.OO 7.50 10.00 12.50 15.00 I I "I , 11 n·3 I r ·0.150 p·0.002 Co.2~~ 7.:50~ S.7:5+ 1.7;:)!: :5.00~ 1.2:5+ 2.150!: AI.2:'+ 13.75+ 12.:'0+ 10.00+ .. .§ '".. Cl.. "o '"..>..o '"'"5 ...... >C II: 1:1c II:.. !n •30 ,·0.83 p <0.001 I I , ~, 11 t 11 2 I d e 12.51)+.. .§11.2:'~ '"10.00~.. CI.... 0 S.1;:)!: <>..7.:50.>.... 0..6.2:'~.. 5....'5.00+..>C II:3.7~. CI - C II:2.;:)0·.. :E.po.I - N L.2~~ SURFACE DISSOLVED OXYGEN (mglll SURFACE DISSOLVED OXYGEN (mg/l)SURFACE DISSO~VED OXYGEN (mg/l) Figure 22.A comparison of surface and intragravel dissolved oxygen concentration (mg/l)data measured at standpipes in Bushrod Slough,Curry Slough,and Slouqh 10 during the ice-covered season,1984-85. -,.J _1 I J J J _J J 1 ),1 ~J 1 ,) 1 )1 BUSHROO SLOUGH CURRY SLOUGH SLOUGH 10 +-----_..--+---------~---------+---------+---------+---------+ 110.00+ .00+••---------+-----.-,.---+--_...-----+---------.---------......--------+.00 IB.J.J.36.67 55.00 73.33 91.67 lJO.OO .0';>+++++•++... .00 IQ.J3 3b.b7 55.00 13.33 "H.b'110.00 .00+++++++..+ .00 10.33 36..67 !l:5.00 7J.JJ 91.67 110.00 'I1 2 I 111 ,d I " 2 II •2',"I / I 21 12 I 1 •1•11 I .. 110.0(1+ .. 100.93: 9~.b7; '"0;:02.:50+ 0(..::>73.33+I- '"OJ Z 6 ...11~ "'">-:5:5.(lO~)( a '""5.B3~..... "'>3l;J.b7~'"a: "0(21.:50+a:.. :!:10.33+ n'73 r '-0.06 9 ••7~p'0.296 AI I 2' ,., II I 110.00+ .-. 100.93+ 9Lb1· Z 0 82.50~0: '"..::>73.33;.. 0( OJ '"b".I7~ "'">-:i:S.OO~)( 0 '"..~.a3; ..... "'>3b.b7~'".. "2?::iO~0(.. I- !;18.33::n •31 r ·0.46 9.17~p.0.004 n'30 r •0.82 P <0.001 2', ,/ I I J 21'. I 100.93.. 'H.b7; Z 0 0:B2.~~'"..::>...73.33+ '"OJ Z .....!7~"'">-:S5.00~)( 0 '""S.6J~..... ill> 0(3ib.b7::.. "0(27.50~..... ~ 10.33+ 9.17· +>0 W sURFACE'lI OXYGEN SATURATION SURFACE 'lI OXYGEN SATURATION SURFACE 'lI OXYGEN SATURATION Figure 23.A comparison of surface and intragravel percent oxygen saturation data measured at standpipes in Bushrod Slough.Curry Slough.and Slough 10 during the ice-covered season.1984-85. • 0 ....., - BUSHROD SLOUGH C1"L.OWER "I)lGI! b"U""Elll'HINS£ ~."..5"".£..D ;••114.ItUllto AO.lIIC[NT VAL.UE ••IUdtlMUIt AD,IIICE",V.At,uiE +81l1.[DIA.tI (,.IS...C.I.A.OUT THE ll[OU," a 11 OUT !-IDE V~LU[ O·'A"OUf510[VALU( NOVEMBER 29,1984 (n =13) JANUARY a,1985 (n=12) JANUARY 30,1985 (n =11) CURRY SLOUGH ------ ----I (~).... -------- --------...- -----(-I +)1--..~---...---- ----..-----II +11---"-....._- I I I I I I 13~0 14~0 15~06.0 7.0 8.0 9.0 10.0 11.0 12.0 NOVEMBER 28,1984 (n=14)• JANUARY 9,1985 (n =II) -----l-t •,1---- ..-----+-1 +l 1------- o ----(+ )1---------JANUARY 29,1985 (n =12) SLOUGH 10 I 6.0 , 7.0 , 8.0 f 9.0 10.0 , 11.0 ,I ,-' 12.0 13.0 14.0 15.0 NOVEMBER 14,1984 (n =4) NOVEMBER 27,1984 (n =15) DECEMBER I I ,1984 (n=15) JANUARY 10,1985 (n=15).. --(I -+1-) ----.._--------------------------1(+'\---- -----------\..)1------------ ----COOl ~)1---- FEBRUARY 1,1985 (n =15)-_·_--------1 (t )-------. APRIL 2,1985 (n =15)---------1 (+[1--------_..------- f I ,,f 6.0 7.0 8.0 9.0 10.0 11.0 ,f I 12.0 13.0 14.0 I 15.0 SURFACE DISSOLVED OXYGEN (mg/l) Figure 24.Summary of surface water dissolved oxygen data (mg/l)measured at standpipes in the middle reach of the Susitna River,by study site and sampling period,ice-covered season 1984-85. 44 u u ..............,)'._-_.!/',\ <!•'-.,--'b • t • 0 II·L.OW("ft ",.MGt b •VPP(A lUNG [ e~M_SPft(...o -toO _EO'"'' (I-'J~"'"C.L ABour rHL IIEOI..... (S.I:IIHIJIIU.aOJACEfIlT VALVl ..~OurSIOE ......uE e ..IIlA;lltMUIlI AOJACENT "'ALUE O·'AR tI1JTSII:)[VALUE BUSHROD SLOUGH NOVEMBER 29,1984 (n =9) JANUARY 8,1985 (n =10) JANUARY 30,1985 (n=II) --.-1 I too) " "--0 "')1 --- -I (+-l CURRY SLOUGH I 3.0 I 4.5 I 6.0 7'.5 9.0 I I I I 10.5 12.0 13.5 15.0 NOVEMBER 28,1984 ----------------(----1 +11---- (n =8)------------------------------ ._-----------------_..._--~-----------------------------1 (t 1---)------ """" - - JANUARY 9,1985 " (n =II ) JANUARY 29,1985 (n =J21 SLOUGH 10 I 1.5 " I 3.0 4.5 ----I ( I 6.0 I 7'.5 t 1-+- I 9.0 I I I 10.5 12.0 13.5 I 15.0 NOVEMBER 14,1984 (n=3) (-1+)----- NOVEMBER 27,1984 ---I (t 1-----I (n =15)------------------------- -------- JANUARY 10,1985 ---I (-1----I (n =15)------------------------ r- I DECEMBER J I.1984 (n =12) ---I ...1----1 FEBRUARY I,1985 (n=14) ----I ..1----- +1-------1-------APRIL 2,1985 (n =14) ----I I 1.5 I 3.0 I 4.5 I 6.0 1.5 I I I I 9.0 10.5 12.0 13.5 I 15.0 r INTRAGRAVE L DISSOLVED OXYGEN l moll) Figure 25.Summary of intragravel water dissolved oxygen data (mg/l)measured at standpipes in the middle reach of the Susitna River,by study site and sampling period,ice-covered season 1984-85. 45 h.~".....l·····;;;·!·:L.::.:.:;:·····\ d •'---....--"• • < • 0 ~, Cl ..LOWIUI MI-lllGE b"UPP!."HINGE c:"IG-SPltEao d·1ll1NIMU."C..IACl'NT .......LUE "•IIlJA'1I:Il:lUlIlI AD..IAC(NT VIILU[ ....lIlED'"'' I J..9'-4 C.I."80UT TNiE ..iEDI4N ...OUT'ID{....ALUE o·'4Ft OUTSIDE ~"'Lut BUSHROD SLOUGH NOVEMBER 29,1984 (n:1:3) JANUARY a,1985 (n::12) ----•t--o 0 [---,..)1-------- """" JANUARY 30,1985 (n=II) ,,--------I (t 1--------- 50 I 55 6 1 0 I 65 I 70 75 I CURRY SLOUGH NOVEMBER 28,1984 (n =14) --(I 1--------- )1-----------..------( --I ..)---------"..JANUARY 9,1985 (n=lI) JANUARY 29,1985 ( n =12)-----,..----,---.,.--..,..--T----,r-----,---.--...---------_-"1'--_-_-_-_--..,..-......, I !I I I I I I I 50 55 60 65 70 75 80 85 90 95 SLOUGH 10 NOVEMBER 14,1984 (n:4 ) -------1(+ NOVEMBER 27,1984 (n:15)"----------------------1 (t DECEMBER I I,1984 (n =(5) --------------{-I + )1---------------" JANUARY 10,1985 (n =15) "----------I (+---)----- FEBRUARY 1,1985 (n=15) "------------------11 1"11-----------""'" APRIL 2,1985 (n=15) ----------------1 [)--- I 50 55 I 60 I 65 70 I 75 I 80 I 85 I 90 I 95 I SURFACE %OXYGEN SATURATION ""'" Figure 26.Summary of surface water percent oxygen saturation data measured at standpipes in the middle reach of the Susitna River,by study site and sampling period,ice-covered season 1984-85. - ...,., 46 .~4 ••••~••1 (..I •..f /---•.....'-.",\ d 0 '-..,.--/b t < • a d"IdHillMUM .I0....Cl!:NT VALUE ••OUT$IO[VALUE t,.IdAXUIUIll 40JACENT "'4"U(0 ..Faft OUTSltll:YAl",U!E- 4·LO'lll1;1It ,.IHG( b·UPP£1IIt HII'ilGE 1:-"6,,,lIt(II.D -+~"'(DIA.N I )..""4 C.l.A.OUT THE IIIlEDIAN BUSHROD SLOUGH NOVEMBER 29,1984 (n =9) JANUARY 8,1985 (n=10) ----;(+1-,--- ..-----1 ..}----- JANUARY 30,1985 ( n =II)....I (+J-- 10 2.0 40 I 50 60 I 70 I 90 CURRY SLOUGH NOVEMBER 28,1984 (n =8)-----------------I--------l +I 1----.........._---........-----------~-_....-----~----..~ JANUARY 9,1985 (n =II) ..---I (I}------ ---------------------_·------1 t +1-'-----)-------------------------------------- JANUARY 29,1985 {n=12l I 10 20 30 I 40 50 I 60 I 70 J 80 I 90 I 100 SLOUGH \0 NOVEMBER 14,1984 (n=3) (1+]1---- ---I (+1------l---------_..._-_._-_...---""'_..--...------------ -----------~------------------I (..1------)- -----------------------------I (..1------l -------------------------------I [+1-------I I 100 T 90 T 80 I 70 I 60 J 50 I 40 I 3020 -------------------------------I [t 1----------J---------------------.------------------ I 10 FEBRUARY 1,1985 (n=14) JANUARY 10,1985 (n=15) APRIL 2,1985 (n=14) DECEMBER I 1,1984 (n=12) NOVEMBER 27,1984 (n=15) - INTRAGRAVEL %OXYGEN SATURATION F'", Figure 27.Summary of intragravel water percent oxygen saturation data measured at standpipes in the middle reach of the Susitna River,by study site and sampling period,ice-covered season 1984-85. 47 .p. 0:> '>1.00+ +---~--~-•._- 9.S0~ B.OQ~ 7.:iO~ 1.00~ X... -'t..~O:!:. '",. '"••00:a: '"...a::li.:liO+ 0-0 :l: 5.00~ ~.~O~ ".OO~ 3.:iO~ BUSHROO SLOUGH ,"I~, 1 1 I , n·17 ,•0.84 P <0.001 8.:iO~ B.OO~ 7.50. 7.00. X.. -'••:50. '"-,. '"••00'"a: '"'"It 5.50~0- :l: 5.00+ ~.:iO+ 4.00~ 3.:liO; CURRY SLOUGH I. l' n·13 r •0.76 p.0.001 s.:liO~ 8.00~ 1.~~ 1.00~ X... 6.~O~..J W,. '"t..oo~It '"...a:~.:liO.0-- :l: :li.oo; 4.~:: 4.00~ 3.~O~ SLOUGH 10 , I :iF, "~j'. , I " n.3 I , •0.96 P <0.001 3.00+...•+__.++----6 + ~.oo 4.00 ~.oo 60.00 1.00 0.00 '1.00 SURFACE pH 3.00;..•++...•+:;;- 3.00 4.00 :i.ao 6.00 7.00 B.OO Y.OO SURFACE pH J.OO+..__~...++••... 3.00 4.00 ~.OO ~.OO 7.00 B.OO q.OO SURFACE pH Figure 28.A comparison of surface and intragravel pH data measured at standpipes in Bushrod Slough.Curry Slough. and Slough 10 during the ice-covered season.1984-85.. J J J t J t I J )))J _J -j 1 .~J J ,- a I LOWE ~IoIllll4[+:IIl lfl-(ClIAN b·UPP(fIl "4"G((I-9''''C.l.AIOUT 'ME 'C"ttv5PREJlD ..£OIA,. tl"llUN'YUIll ACl.lACCJfT ....IoI,.U<•I -OUTSIDE """I,.U(. 1'.IIIlIAJl:llltUIlt ..DJACe:....'""ALU(O·'A"ounnn:....I,.U.[ BUSHROD SLOUGH NOVEMBER 29,1984 (n =0) JANUARY a,1986 (n =7) ---j +1------------------- ----II t )\----JANUARY 30,1985 (n =II) 5.1 5.4 5.7 6.0 6.3 6.6 6.9 7.2 7.5 7.8 8.1 -----1 t 1-1- I +I ...---------_...--------~- 7.8 8.\7.5 ---I (t )-.--- 7.26.9 1------ 6.66.36.0 --I +Il------ + 5.75.45.1 I( CURRY SLOUGH ~- NOVEMBER 28,1984 (n =0)-JANUARY 9,1985 (n =I) JANUARY 29,1985 (n=12) ~ ~SLOUGH 10 ! NOVEM8ER 14,1984 (n =3) If"""NOVEMBER 27,1984 (n:::0) DECEMBER 11,1984 (n=O) JANUARY 10,1985 (n =Z) FEBRUARY 1,1985 (n=15) APRIL 2,1985 (n=15) 5.1 5.4 5.7 6.0 6.3 6.6 6.9 7.2 7.5 7.8 8.1 SURFACE pH Figure 29.Summary of surface water pH data measured at standpipes in the middle reach of the Susitna River,by study site and sampling period,ice- covered season 1984~85. 49 - • 0 -0 "\.o.[~KIMG!:..-..[DUI~ b ~UP,.[II ~t"GI I )..'I'!5-....C.I.".ouT TWE c!...J'll",-:leJlUD llI..ttll.l-'l d.IIlt'.cllllUU AO.l.C[,ff VALUE ••OUTSiDE Yofl4.U( li'.lIUIKIMUIl:l AO ....C[NT VALUIt O·F.III O\lT~IOE 1I',e,4.ut BUSHROO SLOUGH NOVEMBER 29,1984 (n=O ) JANUARY a.1985 (n =6)+I)---------- ""'" JANUARY 30,1985 (n =III '*----(I +I 1---- I 5.1 I 5.4 6.0 I 6.3 I 6.6 7~8 I 8.1 CURRY SLOUGH NOVEMBER 28,1984 (n =0) JANUARY 9.1985 (n=1)+- I :5.1 SLOUGH 10 NOVEMBER 14,1984 { (n=2 ) NOVEMBER 27,1984 ( n =0 ) DECEMBER I I ,1984 (n=O) JANUARY 10,1985 (n =1) FEBRUARY 1,1985 (n=14) APRIL 2,1985 (n=14) I 5.1 r f>I )------------------ I I 5.7 6.0 ---I -t )1----- - - 1 8.1 1 8.1 I 7.8 I 7.8 I 7.5 I 7.5 I 7.2 I 7.2 + I 6.9 , 6.9 -----I I t 1-)--- 1-- I 6.6 I 6.6 )- 6.3 6.3 I 6.0 I 5.7 5.4 I 5.4 (--IJANUARY29,1985 (n=I2.) INTRAGRAVEL pH Figure 30.Summary of intragravel water pH data measured at standpipes in the middle reach of the Susitna River,by study site and sampling period, ice-covered season 1984-85. -50 ~~~~~~1 -1 -..~~1 1 J j )1 }1 J )C} BUSHROD SLOUGH CURRY SLOUGH SLOUGH 10 +-- -------+----- - ---+---------.---------.---------.---------+2::;0.1)0...... .00;+..,++++...+:: .00 4t1.b1 63.33 1.25.00 1606.67 :i'CB.33 ~':iO.OO.._--_-----...-------&----------+---~------..---------..---------+ .00 011'.67 83.33 1~5.00 1t.6.t:.7 209.33 2:50.00 .00++.••••++ .00 4tl,b1 83.3J 125.00 Ibib.h7 208.:3;3 250.00 :I:I 12lsi1.2 I n -7 ~ r -0.74 P <0.001 ••1. I I .:2 t~:l •,i i .'II. I I j,11 .1 f ,II I 22'il.17~ E 2oe.33~ tl it la,..:iO~...ce 166.67~~ >- 1..~."'3~.. ie..a2:S.oo~U ::) C> '"~O...A7;0 U -... III 8J.33~>- '"'a: CI b2.:;O~ '"'~ "1.607:;n -~I i!O r --0.02 p -0.456 2O.P3~ 229.11. I 20S.33:!' 0 lS"':liO~.ce~H.6.67+ >-I-14!1.a3~;; t=--g 12':5.00-; c Z 0 104.11~U Oil 63.33:;I 'I>-I '"'-'IIa: "62.::IO~1'1'•ca:II il- n •30 i!O 41.1:.7+., r •0.75 P <0.001 20.D3~ ., " ."1 12,11 I ' 2:l'i','7:": E 2'08.33+ u it 107.-:10:0 1 lbb.67· >- I ..~.BJ.~t:>-;: U 12:5.0Q~:>c;z 0 104.'7~<)... III a3.3J.:!.>- '"'a: CI t!:.2.50~'"'a:.. i!O 4 ••67. U1 I.....20.a3~ .00+ SURFACE CONDUCTIVITY y..mhos/cm)SURFAce CONDUCTIVITY lrmho./cml SURFACE CONDUCTIVITY y..mho./cml Fi gure 31.A comparison of surface and intragravel conductivity (umhos/cm)data measured at standpipes in Bushrod Slough~Curry Slough~and Slough 10 during the ice-covered season~1984-85. • 0 BUSHROD SLOUGH NOVEMBER 29,1984 (n.:13) JANUARY 8,1985 (n =12) -------------(---I + O-LOW£lt MINGo[ b>r UPP[~MING£ C·H ..SPREAD 1:11.MIN.iliUM ADJAC£I'IT "'''LV( ••IIIAXIIIIUIi AD·JACEHT VALUE 1------- ....£tll ..... t ).9!%C.l.ASOUT TH£ "EDIAI'll ••OUTSiDE YIoLUt: O-FA'f ouTSIDE:vALUlE JANUARY 30,1985 (n=lI) CURRY SLOUGH NOVEMBER 28,1984 (n=14) 20 40 ------1 t ll----- 8 1 0 -(-11---- 120 - JANUARY 9,1985 (n =II) '"-(ill -------(+)1--JANUARY 29,1985 (n=12) SLOUGH 10 I 20 I 40 I 60 I 80 I 100 I~O I I 140 160 ---I(to I 1---------- NOVEMBER 14,1984 ( n =4 ) NOVEMBER 27,1984 ( n =15) DECEMBER I I,1984 (n=15) JANUARY 10,1985 (n =15) --------1(+1- ----------------1 ( ---1(+11 to - FEBRUARY 1,1985 (n=15) --------{..l 1---------- APRIL 2,1985 (n =15) I 20 , 40 I 60 I 80 ----I {to 1----------- I 100 SU RFACE COND UCTI VITY (A,mhos /cm) Figure 32.Summary of surface water conductivity data (umhos/cm)measured at standpipes in the middle reach of the Susitna River,by study site and sampling period,ice-covered season 1984-85. 52 -- ~~"A.o•••1 (.)I•••••••••••I /',\~0 ~b •c • 0 aUSHROD SLOUGH 0°LOWE III HIN...E: D"UP'Pf;A ..111191: c·"'~SP"'EAO d ..IUNI"U"AO.....C[I'IT ....u.V[ .."lilA IIIIUM AOJAC[ftT Y'&IL-.E ....WEDlA" I )."5%C.l.AlOUT TN( IIIEDIA,.. ••QUT'IOt "''-Lul. o ~fAR OUT'SID[YALU[ (--1 ~I \------------- NOVEMBER 29,1984 (n=9) JANUARY e,1985 (n =(0) ( I ~J I o o 1---------- ..... JANUARY ~O,1985 (n::II ) CURRY SLOUGH 40 --(----1 f I 60 .- 80 100 I 120 140 160 240 NOVEMBER 28,1984 (n ::2B) JANUARY 9,1985 (n =II ) [I t J 1-·- ----1-1 ...J 1--------" " ---H ~l 1-------JANUARY 29,1985 (n =12)..a.--ll--------il---------II-II--.,I---r-I---r--.,I---Ir--~-,--I-.....I 40 60 80 100 120 140 160 180 200 220 240 SLOUGH 10 NOVEMBER 14,1984 (n=3) NOVEMBER 27,1984 ( n =15) DECEMBER I I,1984 (n=12) ---(...) -------------I -I- ... 1--)-------------- 1-----)----------- JANUARY 10,1985 (n=15) FEBRUARY 1,1985 (n=14) "-------1 \..11------ ------\1--)-------- r- I APRIL 2,1985 (n=14) I 40 I 60 1 80 ----{...I 1---- ! 100 120 I 140 "" T 160 I ISO I 200 1 220 I 240 ,.- 'l, INTRAGRAVEL CONDUCTIVITY (~mhos/cm) Figure 33.Summary of intragravel water conductivity data (umhos/cm)measured at standpipes in the middle reach of the Susitna River,by study site and sampling period,ice-covered season 1984-85. 53 _________~"""""'====~-~-~~"_1 r- I r -I I 4.0 DISCUSSION 4.1 General Evaluations of Potential Mitigation Sites at Side Slough, Upland Slough,and Side Channel Habitats A discussion of the various potential mitigation sites evaluated during this study is presented in the following sections by habitat type.This discussion focuses on identifying the habitat types most suitable for provi di ng improved salmon spawning habitat by phys ica lly modifyi ng the habitat.However,a great degree of variability exists in the physical and biological characteristics between potential mitigation sites within a particular habitat type,making it difficult to identify a specific habitat type as being most suitable for mitigation purposes.While this discussion attempts to identify which habitat types generally appear to be most suitable for mitigation purposes,it should be noted that exceptions occur within each habitat category. Because of the variables involved in evaluating potential mitigation sites,the suitability of individual sites cannot be ranked based on the available data.Recommendations for specific sites which generally appear to be most suitable for mitigation are present~d in this dis- cussion.However,the selection of these sites was based on field observations and 1imited data,therefore a more detailed eva 1uati on should be conducted to determine if these sites are the most practical sites for mitigation purposes.This determination should include a detailed evaluation of the selected mitigation technique,logistics, physical and biological characteristics of the site as they relate to the salmon species of interest,and a cost/benefit analysis.This study only evaluates the mitigation potential of sites under current habitat conditions and any changes to the habitat that may take place in the future as a result of construction and operation of the proposed hydro- electric project may necessitate a reevaluation of these sites.Further analysis and mitigation planning will be conducted by the primary mitigation contractor (ENTRIX,Inc.). 4.1.1 Side Channel Habitats In general,side channel habitats exhibit one or more of the following limiting factors:1)substrates are generally large and well cemented with only 1imited areas suitable for spawning;2)upwell ing and bank seepage is limited and frequently intermittent,ceasing completely during the ice-covered season;3)passage into and within the site is a problem in the 9,000 to 12,000 cfs range;4)sites frequently dewater and freeze in the winter;and 5)frequent overtopping occurs during the winter as the river stages.Due to the numerous limiting factors associated with side channel habitats,it is felt that under current conditions slough habitats provide a more viable option as salmon spawning mitigation sites. 4.1.2 Upland Slough Habitats Upland slough habitats are located in protected channels that do not overtop either during the open-water or ice-covered periods.The 54 primary l"imiting factors affecting upland sloughs in regard to mitiga- tion sites are:1)passage restrictions at the 9,000 to 12,000 cfs range;2)the presence of thick deposits of silt (unsuitable for salmon spawning)due to the lack of flushing flows;3)lack of strong continu- ous upwelling (with the exception of Sloughs 98,10,and 17);and 4) extensive beaver activity resulting in passage restrictions due to beaver dams.Although internal passage problems exist in the 9,000 to 12,000 cfs range,passage problems are primarily expected to occur at the mouth of the upland sloughs.The mouths of upland sloughs generally have a silt/sand bar which would restrict passage at lower discharges. Upland sloughs generally act as large backwater areas which eliminates passage problems while at the same time creating substrate problems. Due to the lack of flow and the backwater effects which occur in upland sloughs,suspended sediments are able to settle out creating thick deposits of silt and sand.The thick silt deposits affect spawning in two ways:1)by not providing suitable spawning substrate and 2) affecting incubation conditions within the intragravel environment. Most of the upland sloughs examined lack the strong continuous upwelling that would be needed to provide a stable incubation environment.Where spawning occurred in areas of thick silt deposits,such as Slough 98, strong upwelling was also present to stabilize the incubation environ- ment. Upland sloughs provide an ideal habitat for beaver colonies.Eighty- eight percent of the upland sloughs surveyed have beaver activity.The primary affect of the beaver activity upon adult salmon is 1imiting passage to spawning areas by construction of dams. Of the sixteen upland sloughs surveyed,seven should be considered for further study as mitigation sites (Sloughs 3A,Curry,80,98,10,17, and 19).While each of these sites exhibit one or more of the primary limiting factors,the degree to which they occur is not as great as in other sites.Also,salmon spawning has occurred at each of these sites in at least one previous year.In general,the factors limiting spawning in these sites can be confined to passage and substrate,both of which can be overcome by mechanical habitat alteration.Beaver activity,which is a primary concern in Sloughs 98,10,and 17,can be overcome by removal of the beavers or a maintenance program of opening the dams during the spawning period.An additional problem unique to Slough 98 is that passage must be provided through Slough 9 in order for salmon to reach the mouth of Slough 98. 4.1.3 Side Slough Habitats Side slough habitats are the most numerous habitat type observed.Of - the habitats looked at in this study,side sloughs support the greatest numbers of spawning salmon in the middle reach and appear to be best suited for habitat modifi cati on.The primary probl ems associ ated with side sloughs are:1)restricted passage in the 9,000 to 12,000 cfs range;2)poor substrate conditions;and 3)winter overtopping in some sites.These limiting factors can readily be corrected through mechan- ical habitat alteration techniques. 55 r I Of the 23 side sloughs studied,12 sites,all presently supporting spawning salmon populations',should be considered for further study as mitigation sites.These sites are Whiskers Slough,Slough 8,Bushrod Slough,and Sloughs 8B,SA,9,9A,11,16B,20, 21,and 22.Sloughs 8A, 9,11,and 21 have already been addressed in the Fish Mitigation Plan (Moulton et al.1984).Habitat modifications in the other sites can be readily accomplished to provide increased spawning or,as in the case of Slough 16B,to provide increased spawning and a suitable habitat which would attract spawners annually and allow successful development of their eggs and fry. 4.2 Opening of Beaver Dams to Improve Fish Passage Conditions Fi sh passage restri ctions,parti cul arly due to beaver dams,occur in upland and side slough habitats in the middle reach of the Susitna River.Possible mitigation options would be to either:1)remove the beavers and their dams completely;or 2)have a maintenance project to open dams during the spawning season;or 3)upgrade the habitat below the dams. Beaver dams were periodically opened at selected slough sites during the salmon spawning period to observe whether salmon would utilize pre- viously inaccessible spawning habitat.In all cases except one,fish readily migrated through the dams and utilized spawning habitat above the dams.The one exception was Slough 4,a site previously unutil ized by salmon.Spawning salmon were not observed in this slte after removal of the dam.Further habitat modification may be necessary to make this site suitable for spawning.Although incubation conditions were not monitored at these sites,it was assumed that spawning would be success- ful based on previous spawning survey data from these areas (ADF&G 1981, ADF&G 1983a;Barrett et al.1984).Based on limited data,it appears as if opening or removing dams and removing beavers would be a viable option for providing additional spawning habitat.Of the three options, the most practical appears to be periodically removing the beavers and their dams.Without removing the beavers,it is a somewhat futile effort to attempt to keep dams open to provide passage,since the dams would be rebuilt overnight.When considering mitigation alternatives, this option could be considered in order to increase spawning areas in Sloughs 9 and 9B.Upgrading spawning habitat downstream of the dams may be possible although it may be more expensive and short lived if the beavers extend their range downstream in a site. 4.3 Identification of Habitat Modification Technigues at Selected Slough Sites The primary purpose of the ice covered studies was to further examine selected sites to identify possible habitat modifications to improve salmon spawning and incubation habitat.The ice-covered studies examined three sites (two upland sloughs and one side slough)that appeared to have high potential as successful mitigation sites.The three sites (Bushrod Slough,Curry Slough,and Slough 10)were selected based on the results of the open-water surveys.These sites are 56 generally representative of each habitat type and exhibit problems limiting salmon spawning that can be found in all habitat types studied. One of the primary requirements for successful development and survival of salmon embryos is the presence of a suitable incubation environment. Incubating salmon embryos require a constant supply of water which is of suitable temperature,containing sufficient dissolved oxygen,and free of toxic substances.The rate of flow and quality of intragravel water is influenced by the substrate composition.Therefore,the successful development and survival of salmon embryos is directly related to both the physical and chemical characteristics influencing the intragravel water surrounding the developing embryos.The significance of the various parameters on embryo development in the middle Susitna River has been presented in detail in Vining et al.(1985).The incubation habitat should be examined both prior to and after any habitat modi- fication projects designed to improve spawning.This will not only provide additional baseline data on which to make more accurate manage- ment decisions,but will also provide a measure of success of the habitat modification techniques by comparing incubation conditions before and after alteration of the habitat. 4.3.1 Bushrod Slough This site was selected for detailed study because,in the proposed range of project discharges,it exhibits problems that may be expected to occur in other side slough habitats.Initial surveys of this slough indicated generally favorable conditions for salmon spawning and incu- bation throughout the site even though pink and chum salmon have only been observed spawning at this site during 1984,and then only in the lower pool.The primary problem in Bushrod Slough appears to be two passage reaches located at the mouth and mi d-s 1ough.The passage reach at the mouth presents a problem only at flows less than 12,000 cfs.The mid-slough passage reach is unpassable at all discharges below the breaching discharges.Secondary problems in the upper pool are dewater- ing and limited bank seepage and upwelling. Bushrod Slough consists of two pools separated by a riffle within well defined banks.The physical size of the pools as well as both surface and intragravel water quality and substrate composition is almost identical in the two pools.The substrate in the upper pool exhibits a slightly higher percentage of fines less than 0.84 mm which appear to be sl i ghtly more cemented than the lower pool.Because of such close similarities in the data between the two pools,it was felt that passage or upwelling must be the factors limiting spawning to the lower pool. It was observed that,during breaching conditions,when passage was possible through the mid-slough riffle,chum salmon did not migrate to the upper pool to spawn.This indicates that although passage is a factor limiting spawning at lower flows,another factor such as limited upwelling may be the controlling factor which limits spawning in the lower pool.The upwelling in the lower pool remained constant through- out the year whereas only limited bank seepage was observed in the upper pool.This seepage in the upper pool occurred along the right bank and 57 - - ~l ~ I r I I 1'- I I appears to be related to mainstem discharge.As the mainstem discharge dropped in the fall,the bank seepage in the upper pool ceased.This pool eventually dewatered completely and froze prior to the river staging.Once the river staged,water was again present throughout the winter but the substrate remained frozen except for the top six inches. 4.3.2 Curry Slough Curry Slough is a former side channel/side slough of the Susitna River at whi ch a ten foot hi gh berm was bU'i 1t across the head of the si te by the Alaska Railroad.This was done to prevent breaching of the site and subsequent erosi on of the ra 11 road tracks whi ch run along the ri ght bank of the slough.As a result,there are no breaching discharges to flush accumulated sediments from the site.Backwater effects at high mainstem discharges continually add to the silt accumulation.Chum salmon spawn"i ng was fi rst reported at th issite du ri ng 1984 when a tota 1 of eight chum salmon were observed. This site was included in the detailed study for several reasons.It is indicative of sites having passage and substrate problems which limit spawning. The lower half of the slough,which dewaters as the mainstem discharge decreases,is the primary area where passage problems occur in the site. This can possibly be overcome by mechanically creating a deeper channel to permit passage of salmon at low mainstem discharges. The area of primary interest in Curry Slough is the upper two-thirds of the site,consisting of a long-deep pool and a riffle.Once fish negotiate the passage problems at the mouth,they encounter no further passage restrictions unt"il they reach the riffle at the head.Water levels in the pool dropped during the winter but water quantity and quality were still suitable for embryo incubation (Appendix Table E-1). The source of water is constant upwelling and bank seepage that occurs in the riffle area located in the upper 300 feet of the slough.The upwelling supplies water of adequate temperature and quality to allow for successful incubation.When comparing water qual ity in the three areas of the slough,the riffle area (s.tandpipe 11-15)has the most favorable measurements (Appendix Table E-1). The main problem appears to be the existing substrate.It is either too large or too fine with thick silt deposits covering the entire slough. Another potential problem is any undetermined adverse effects of the Alaska Railroad.During the winter,tons of snow are plowed off the railroad tracks into the slough.This may affect the water quality in the slough due to the debris and chemi ca 1s associ ated wi th the ra i1road that are mixed in the snow. The problems which limit spawning in Curry Slough may be overcome by providing passage,relocating the channel away from the railroad tracks, replacing the substrate,and providing a berm at the lower end to maintain pool depth. 58 4.3.3 Slough 10 Slough 10 is an upland slough that was selected for detailed study because substrate appears to be the primary factor 1imiting spawni ng. There are no passage problems at this site except at the mouth at a discharge range less than the expected post project discharges.The lower half of this slough is a large backwater area with thick deposits of silt. Substrate samples indicate that 78%of all substrates in Slough 10 are less than 1.0 mm.The accumulation.of fines is generally uniform throughout the 16-inch sample depth.The fredle index analysis indicates that the lower eight inches is almost all silt.The fredle index is strongly influenced by the sample obtained in the present spawning area,and is therefore somewhat misleading at this site.At present there is only a 1imited area near the head of the northwest channel that is suitable for spawning.All chum salmon spawning observed in Slough 10 has occurred in this area.As a result,the fish that spawn later are spawning on top of earlier spawner's redds. Because of crowding of eggs in the redds,survival of incubating embryos may not be as good as it mi ght be in an undi sturbed redd (McNeil 1969). No spawning has ever been observed in the northeast channel where sub- strates are primarily silt,cobble,and boulder. Intragravel water quality throughout the site is generally suitable for spawning.The effects of silt and decaying organic matter on water quality can be observed by comparin~the average dissolved oxygen readings in the heavily silted areas(l.l mg/l)with those with less silt accumulation such as the northeast channel (7.1 mg/1)or the northwest channel spawning area {6.6 mg/l}.This clearly illustrates the deleterious effects of excessive silt and decaying organic matter on water quality.It is interesting to note while the northeast channel has higher average dissolved oxygen readings and comparable tempera- tures,no spawning occurs in this channel.This is most likely due to the substrate composition. Water quality and temperature are maintained all year by strong and constant upwe 11 i ng and bank seepage present throughout both channels in Slough 10.Due to the constant upwelling,this is one of the only sites that remains ice free except for periods of extreme cold.Because of the presence of upwelling throughout the slough,one would expect chum salmon to spawn everywhere.However,salmon only spawn in a limited area in Slough 10,which indicates that substrate may be a 1 imiting factor in this case.Alevins were observed in the gravel at Slough 10 in January,earlier than other sites,which may be attributable to the continuous upwelling. A potential problem in Slough 10,as in other upland sloughs,is the presence of beavers.Beaver activity has eliminated passage to spawning areas used during 1983. 59 ~I - ~I !- """! r I.I 4.4 Conclusions/Recommendations Conclusions Recommendations for specific sites which generally appear to be most suitable for mitigation are presented in the discussion.However,the selection of these sites was based on field observations and limited data,therefore a more detailed evaluation should be conducted to determine if these sites are the most practical sites for mitigation purposes.This study only evaluates the mitigation potential of sites under current habitat conditions and any changes to the habitat that may take place in the future as a result of construction and operation of the proposed hydroelectric project may necessitate a reevaluation of these sites. 1.Based on observed conditions in the anticipated minimum mainstem discharge range of 9,000 to 12,000 cfs,side slough habitats appear to present the best probabil ity of success as miti gati on sites,usi ng habitat modi fi cation techni ques,for chum and sockeye salmon in the middle Susitna River. 2.Based on these initial surveys it appears that the removal of fish passage restrictions at selected sites would be a successful mitigation alternative to improve chum and sockeye salmon spawning conditions. 3.Habitat modifications to correct substrate and upwelling limitations would only be applicable at a limited number of sites. Recommendati ons 1.Small scale habitat alteration projects should be conducted to demonstrate feasibility of habitat alteration as a mitigation option in the Susitna River. For example,Bushrod Slough could be used to test the effects of removing fish passage restrictions,increasing upwelling, and pl acei ng a protective berm at the head of a slough to prevent breaching. Curry Slough is a possible site for development of an experimental salmon spawning channel (Moulton et al.1984). The berm at the head of this site should provide protection to habitat modifications made at this site.The close proximity of the Al aska Rail road tracks woul d provi de good access to this site for equipment and supplies.Another mitigation option that might be considered at Curry Slough is the use of incubation boxes (Roberson and Holder 1983;Moulton-et ale 1984)using the existing water system at Curry. 60 2.A study of incubation conditions should be included in any mitigation plan to insure the success of habitat modification for mitigation purposes.- 3.Although chum and sockeye salmon were the primary species of interest in this study,other salmon species may be considered for mitigation purposes if conditions at a specific site appear more favorable to a particular species. 4.Other factors such as engineering,economics,and logistics were not included in this report but should be evaluated when considering other sites selected for habitat modifications. ,cs;;;r, 61 .... r 5.0 Contributors Adult Anadromous Project Leader Data Processing Project Leader Graphics Typing Staff Editor Data Collection Data Analysis Text 62 Bruce M.Barrett Allen Bingham Carol Hepler Roxann Peterson Peggy Skeers Vicki McCall Bobbie Greene Joe Sautner Drew Crawford Barry Stratton Bob Wilkey Don Seagren Tommy Wi throw Sheri Methven Pat Morrow Allen Bingham Don Seagren Bob Wilkey Teri Keklak Donna Buchholz Chuck Miller Alice Freeman Don Seagren Bob Wilkey r r- I ".... i I i""" j I F"'" I I 6.0 Acknowledgements Special appreciation is extended to the following people for their contribution to this study: Steve Crumley,Elizabeth Bradley,and Tim Jennings of Entrix, Inc.for their assistance in field data collection and helpful insights into the use of the freeze core sampler. State of Alaska,Department of Transportation,for assistance in analyzing substrate samples at their laboratory facility. Carol Kerkvliet of Woodward Clyde Consultants for her assistance in winter field data collection. 63 - I I i 7.0 Literature Cited Acres American,Inc.(Acres).1982.Susitna Hydroelectric Project, Federal Energy Regulatory Commission (FERC)License Application, Exhibit E,Draft.Anchorage,Alaska. ____=.1983.Susitna Hydroelectric Project FERC License Application. Exhibit E.Volume 6A Chapter 3.Prepared for Alaska Power Authority,Al aska Department of Commerce and Economi c Development, Anchorage,Alaska. Alaska Department of Fi sh and Game.1981.Adult anadromous fi sheri es project (June-September 1981).Susitna Hydro Aquatic Studies. Phase 1 final draft report.Subtask 7.10,Alaska Department of Fish and Game,Anchorage,Alaska • .1983a.Adult anadromous fish studies,1982.Susitna Hydro----rAquatic Studies.Phase 2 final report.Volume 2.Alaska Department of Fish and Game,Anchorage,Alaska. .1983b.Winter aquatic studies (October 1982 -May 1983).-----=Susitna Hydro Aquatic Studies.Phase 2 Report.Alaska Department of Fish and Game,Anchorage,Alaska. __.1984.Susitna Hydro Aquatic Studies procedures manual (May 1983 -June 1984).Susitna Hydro Aquatic Studies.Alaska Department of Fish and Game,Anchorage,Alaska. Ameri can Associ ati on of State Hi ghway and Transportati on Offici a 1s. 1982.Standard methods of sampling and testing.13th edition. Washington,D.C. Bakkala,Richard G.1970.Synopsis of biological data salmon,Orchorhynchus keta (Walbaum)1792.U.S.Dept. USF&WS.FAD Species Synopsis No.41.Circular 315. D.C.89 pp. on the chum of Interior. Washington, Barrett,B.M.,F.M.Thompson,and S.N. fish studies:May -October 1983. Report No.1.Alaska Department Alaska. Wick.1984.Adult anadrmous Susitna Hydro Aquatic Studies. of Fi sh and Game,Anchorage, 1985.Adult anadromous fish investigations:May -October 1984.Susitna Hydro Aquatic Studies.Report No.6.Alaska Department of Fish and Game,Anchorage,Alaska. Blakely,J.S.,J.S.Sautner,L.A.Rundquist,and N.E.Bradley.1985. Salmon passage validation studies (August -October 1984).Susitna Aquatic Studies Program.Addendum to Alaska Department of Fish and Game Report No.3,Chapter 6.Alaska Department of Fish and Game, Anchorage,Alaska. Canada,Government of.Canada Department of Fisheries and Oceans. 1980.Stream enhancement guide.Ministry of Environment. Vancouver,British Columbia. 64 Cooper,A.C.1965.The effect of transported stream sediments on the survival of sockeye and pink salmon eggs and alevin.International Pacific Salmon Fisheries Commission.Bulletin 18.New Westminster,Canada. Everest,F.H.,C.E.McLemore,and J.F.Ward.1980.An improved tri-tube cryogenic gravel sampler.Res.Note PNW-350.Portland, OR:U.S.Department of Agriculture,Forest Service,Pacific Northwest Forest and Range Experiment Station,8 pp. Everest,F.H.,F.B.Lotspeich,and W.R.Meahan.1981.New perspective on sampling,analysis,and interpretation of spawning gravel quality.Presented at the Symposium on Aquisition and Utilization - of Aquatic Habitat Inventory Information.Portland,Oregon. Hale,S.S.1981.Freshwater habitat relationships chum salmon (Oncorhynchus keta).Alaska Department of Fish and Game,Habitat Division,Resource Assessment Branch.Anchorage,Alaska. Harrison,C.W. Fish.Soc. 1923.Planting eyed salmon and trout eggs. 53:191-200. Trans.Am. Harza-Ebasco Susitna Joint Venture (Harza-Ebasco). alternative flow requirements.Prepared Authority,Anchorage,Alaska. 1984.Evaluation of for Alaska Power Keklak,T.and T.Withrow.1985.Continuous water temperature investigations.Susitna Aquatic Studies Program.Task 29 and 37 Support Technical Report.Alaska Department of Fish and Game, Anchorage,Alaska. Keklak,1.and 1.Quane.1985.Appendix F:Winter temperature data. Volume 2 In:C.C.Estes,J.Sauner,D.S.Vincent-Lang,editors. Winter aquatic investigations (September 1983 -May 1984).Susitna Aquatic Studies Program.Report No.5.Alaska Department of Fish and Game,Anchorage,Alaska. Kogl,D.R.1965.Springs and groundwater as factors affecting survival of chum salmon spawn in a sub-arctic stream.Master1s thesis. University of Alaska,Fairbanks,Alaska. Krueger,S.1981.Freshwater habitat relationships:pink salmon (Oncorhynchus gorbuscha).Alaska Department of Fish and Game, Habitat Division.Anchorage,Alaska. Lotspeich,F.B.and F.H.Everest.1981.A new method for reporting and interpreting textural composition of spawning gravel.Research Note PNW-369.Portland,Oregon.U.S.Department of Agriculture, Forest Service,Pacific Northwest Forest and Range Experiment Station,llpp. Merritt,M.F.and J.A.Raymond.1982.Early life history of chum salmon in the Noatak River and Kotzebue Sound.Alaska Department of Fish and Game,Division of Fisheries Rehabilitation,Enhancement and Development.Juneau,Alaska. 65 - l""" I t-. I Morrow,J.E.1980.The freshwater fishes of Alaska.Alaska Northwest Publishing Company.Anchorage,Alaska. Moulton,L.L.,L.A.Rundquist,S.C.Crumley,and N.E.Bradly.1984. Susitna Hydroelectric Project fish mitigation plan.Woodward-Clyde Consultants.Prepared for Harza-Ebasco Susitna Joint Venture. November,1984.Document No.2466,Susitna File No.4.3.1.4. Anchorage,Alaska. McNeil,W.J.and W.H.Ahnell.1960.Measurement of gravel composition of salmon streambeds.Fisheries Research Institute,College of Fisheries,University of Washington,Seattle,Washington.Circular No.120.Prepared for U.S.Department of the Interior,Fish and Wildlife Service,Bureau of Corrmercial Fisheries.Contract #14-17-008-96. McNeil,W.J.1962.Variations in the dissolved oxygen content of intragravel water in four spawning streams of Southeastern Alaska. U.S.Fish and Wildlife Service,Special Scientific Report - Fisheries,No.402,15 pp. McNeil,W.J.and W.H.Ahnell.1964.Success of pink salmon spawning relative to size of spawning bed materials.U.S.Fish and Wildlife Service Special Scientific Report -Fisheries,No.469.15 pp. McNeil,W.J.1969.Survival of pink and chum salmon eggs and alevins. Pages 101-117 in T.G.Northcote,editor.Symposium of salmon and trout in streams.University of British Columbia,Vancouver, Canada. Olsen,J.C.1968.Physical environment and egg development in a mainland beach area and an island beach area of Iliamna Lake.In Burgner,R.L.editor.Further studies of Alaska sockeye salmo"'il.'" University of Washington Publications in Fisheries,New Series, Volume III.University of Washington,Seattle,Washington. Phillips,R.W.,R.L.Lantz,E.W.Claire,and J.R.Moring.1975.Some affects of gravel mixtures on emergence.of coho salmon and steelhead trout fry.Trans.Am.Fish.Soc.104(3):461-466. Platts,William S.,Walter F.Megahan,G.Wayne Minshall.1983. Methods for evaluating stream,riparian,and biotic conditions. Gen.Tech.Rep.INT-138.Ogden,UT:U.S.Department of Agri- culture,Forest Service,Intermountain Forest and Range Experiment Station,70 pp. Porter,P.E.,and J.R.Rogers.1984.A computer program to characterize the textural composition of salmonid spawning gravel. Presented to American Fisheries Society,Alaska Chapter Annual Meeting,1984.Forestry Sciences Laboratory,Juneau,Alaska. 66 Quane,T.,1.Queral,T.Keklak and D.R.Seagren.1984.Channel geometry investigations of the Susitna River basin.Chapter 2 ~ C.C.Estes and D.S.Vincent-Lang,editors.Aquatic habitat and i nstream flow i nvesti gati ons (May -October 1983).Susitna Hydro Aquatic Studies.Report No.3.Alaska Department of Fish and Game,Anchorage,Alaska. Reiser,D.W.and T.C.Bjornn.1979.Influence of forest and rangeland management on anadromous fish habitat in western North America. Number 1.Habitat Requi rements of Anadromous Sa lmoni ds.United States Forest Servi ce General Techni ca 1 Report PNW-96.Portl and, Oregon. Ringler,N.H.and J.D.Hall.1975.Effects of logging on water temperature and dissolved oxygen in spawning beds.Trans.Am. Fish.Soc.104(1):111-121. Roberson,K.and R.Holder.1983.Gulkana River sockeye enhancement, July 1,1980 -June 30,1981.PWS 011.Alaska Department of Fish and Game,Division of Fisheries Rehabilitation,Enhancement,and Development.Juneau,Alaska. Roth,K.1984.Personal communication.Alaska Department of Fish and Game,Susitna Hydro Aquatic Studies,Anchorage,Alaska. Ryan,LA.,Jr.,B.L.Joiner,and B.F.Ryan.1982. manual.Minitab Project,The Pennsylvania University Park,Pennsylvania,USA. Minitab reference State University, Sautner,J.S.,L.J.Vining,and L.A.Rundquist.1984.An evaluation of passage conditions for adult salmon in sloughs and side channels of the mid~le Susitna River.Chapter 6 in C.C.Estes,and D.S. Vincent-Lang,editors.Aquatic habitat and instream flow investi- gations (May -October 1983).Susitna Hydro Aquatic Studies. Report Number 3.Alaska Department of Fish and Game,Anchorage, Alaska. Scott,W.B.and E.J.Crossman.1973. Fisheries Research Board of Canada. Freshwater fishes of Canada. Bulletin 184.Ottawa,Canada. - ~, - Scrivener,J.C.,and M.J.Brownlee.1981.A preliminary analysis of Carnation Creek gravel quality data,1973-1980.p.195-226.In Salmon spawning gravel:A renewable resource in the Pacific Northwest?Proceedings of the conference.Washington State University,Pullman,Washington. Sheridan,W.L.1962.Water flow through a salmon spawning riffle in southeastern Alaska.U.S.Fish and Wildlife Service Spec.Sci. Rep.-Fish No.407.22 pp. Shirazi,M.A.,and W.K.Seim.1980.A stream systems evaluation -an emphasis on spawning habitat for sa1monids.Report No.EPA 60013-79-109.Envi ronmenta 1 Research Laboratory-Corva 11 is,Offi ce of Research and Development,Environmental Protection Agency, Corvallis,Oregon. 67 '"'"' - /""'i I I r r r I r Stuart,LA.1953.Spawning migration,reproduction and young stages of the Loch Trout (S.Trutta).Freshwater Salmon.Fish Res. Home Dep.,Scotl and.-Rep.No.5.39 p. Terhune,L.D.B.,1958.The Mark VI Groundwater Standpipe for measuring seepage through salmon spawning gravel.Fisheries Research Board of Canada Journal 15(5):1027-1063. Trihey,E.W.1982.Preliminary assessment of access by spawning salmon into side slough habitat above Talkeetna.Prepared for Acres American,Incorporated.Anchorage,Alaska. Trihey,E.W.,L.J.Vining,C.C.Estes,D.R.Seagren,and A.G.Hoffman. 1983.Timing and passage of adult samon in the mainstem Susitna River and access into selected sloughs upstream of the Chulitna River confl uence.Appendi x B In:ADF&G.Synops is of the 1982 aquatic studies and analysis of fish and habitat relationships (2 of 2:Appendices).Susitna Hydro Aquatic Studies.Phase 2 report. Alaska Department of Fish and Game,Anchorage,Alaska. Vaux,W.F.1962.Interchange of Stream and Intragrave 1 Water ina Salmon Spawning Riffle.U.S.Fish and Wildlife Service,Special Scientific Report-Fisheries,No.405,11 pp. Velleman,P.F.,and D.C.Hoaglin.1981.Applications,basics,and computing of exploratory data analysis.Duxbury Press,Boston, Massachusetts,USA. Vincent-Lang,D.S.,A.G.Hoffman,A.E.Bingham,C.C.Estes,D.Hilliard, C.Stewart,E.W.Trihey,and S.C.Crumley.1984.An evaluation of chum and sockeye salmon spawning habitat in sloughs and side channels of the middle Susitna River.Chapter 7 in C.C.Estes,and D.S.Vincent-lang,editors.Aquatic habitat and instream flow investigations (May -October,1983).Susitna Hydro Aquatic Studies.Report Number 3.Alaska Department of Fish and Game, Anchorage,Alaska. Vining,L.J.,J.S.Blakely and G.M.Freeman.1985.An evaluation of the incubation life-phase of chum salmon in the middle Susitna River,Alaska.Volume 1 in C.C.Estes,J.Sautner,and D.S. Vincent-Lang,editors.Winter aquatic investigations (September 1983 -May 1984).Susitna Aquatic Studies Program.Report No.5. Alaska Department of Fish and Game,Anchorage,Alaska. Walkotten,W.J.1976.An improved technique for freeze sampling streambed sediments.Res.Note PNW-281.Portland,OR:U.S. Department of Agriculture,Forest Service,Pacific Northwest Forest and Range Experiment Station,11 pp. Wendling,F.L.1976.Preliminary report on gravel porosity studies along the Trans-Alaska Pipeline.Draft Report.National Marine Fisheries Service.Anchorage,Alaska. 68 Woods,Paul F.1980.Dissolved oxygen in intragravel water of three tributaries to Redwood Creek,Humboldt County,California.Water Resources Bulletin,Vol.16,No.1.Paper No.79034.Minneapolis, Minnesota,pp.105-111. 69 """ ...... --8.0 APPENDICES Appendix A.Study Site Descriptions and Site Maps ...•.A-I Appendix B.General Surface Water Quality and Intragravel Water Temperature Data........8-1 I""'" ! I Appendix C. Appendix D. Salmon Spawning Distribution Data ........• Selected Physical and Chemical Requirements for Various Life C-I -i Stages of Salmon Species..................D-l r r I r 1 I I Appendix E. Appendix F. Winter Water Quality Data •••..•.•......... Freeze Core Substrate Data •...••••••.•••.. 70 E-l F-l ,~ APPENDIX A STUDY SITE DESCRIPTIONS AND SITE MAPS. A-I - r Slough 1 (RM 99.5R) Slough 1 appears to be a remnant side channel functioning as an upland slough approximately 50 feet wide and 1,600 feet long.Under the observed range of discharges,the slough appears to be a long continuous turbid backwater with minimal flow.Beaver activity is prevalent throughout the slough,with a lodge present along the ri ght bank near the mouth but no dams at present.At anticipated project discharges, the present sand bar at the mouth would not restrict fish passage. The upper 100 to 200 feet of the slough divides into two clear water channels (Appendix Figure A-I).The large gravel -small gravel substrate in this area is covered by a layer of silt and organic debris. Due to the depth of the water and high turbidity,it was not possible to accurately determine substrate composition in the remainder of the slough.It is presumed,based on slough conditions,that the thick layer of silt and organic debris continues throughout this area.The banks are covered with a combi nati on of grasses,shrubs and mi xed deciduous-coniferous trees with a ridge paralleling the right bank of the slo~gh.The left bank is low and marshy,and is dissected by canals as a result of beaver activity.No upwell ing or bank seepage was observed throughout this site. In late August,1984,24 chum salmon and two sockeye salmon were observed in the upper end of the slough,(Appendix Figure A-2)with some chum salmon spawning being observed at this time. Substrate~lack of upwelling and low flows appear to be the main factors limiting spawning in this site. Slough 2 (RM 100.7R) This is an 0.3 mile long bow shaped side slough on the east side of the Susitna River with a backwater area extending 500 feet upstream from the mouth,followed by a pool riffle sequence.A small bog fed creek drains into the ri ght side of the slough near the head of the fi rst pool. Upwell ing and bank seepage are present along the left bank of the upper pool and appears to be related to mainstem discharge (Appendix Figure A-3).Upwelling present along the right bank,downstream of the creek, appears to be related to bog drainage. In the backwater areas si lt and sand cover the 1arger substrate to a depth of approximately one foot.Upstream of the backwater,the two pools have rubble/large gravel substrates interspersed with boulders and silt.The best substrate is along the right bank of the first pool where there are pockets of large gravel/rubble (Appendix Figure A-4).A cobble/boulder berm is present at the head.There are two areas where passage may be restricted,a large sand/silt bar present at the mouth and the 20 foot riffle between the backwater and first pool. In 1984 chum and sockeye salmon were reported spawning in the backwater area and the first pool.The redds in the first pool were located in an upwelling area downstream of the bog creek along the right bank (Appendix Figure A-3).Fry were observed in both pools. A-2 :P I W (JJ o 300 1 I FEET (Approlt.Scale) j i ...------SUSITNA 1 RIVER (9 RM 100.0 LG-SG-SI [!]WATER QUALITY MEASUREMENT SITE*INTRAGRAVEL TEMPERATURE SITE ) Appendix Figure A-I.Substrate composition and sampling locations in Slough 1 (RM 99.R). ;po i -~ & o 300 I , FEET (Approx.Scale) ~SUSITNA RIVER EeRM 100.0 ----- ':·;",:/"Ii, SALMON SPAWNING AREAS ~CHUM a SOCKEYE, tlliiliI 1984 Appendix Figure A-2.Salmon spawning locations in Slough 1 (RM 99.5R). J ,~~J cB t .~J J J ,J 5 1 »1 J :••;1"';0'-;"''''. ~UPWELLING )::0 I U'I l···" .t. ;!f. / SALMON SPAWNING AREA S ~CHUM a SOCKEYE, llitJ.1984 sustfNA RI VER ~~<i;f!MN!1~:"\\~;.;';z.~~~..:~ 5/0 Ii Q RM 10\.06) ~ a 250 I I FEET I ApprOI\.Scale) Appenrlix Figure A-3.Upwelling and salmon spawning nreas in Slough 2 (RM lOO.7R). The factors that appear to be limiting to spawning are passage into and within the slough,substrate and limited upwelling. Whiskers Slough (RM 101.2L) Whiskers Slough is a 0.5 mile long side slough located on the west bank of the Susitna River with the head joining Slough 3B.The confluence of Whiskers Creek is on the left bank,0.2 miles upstream of the mouth. Breaching of the head occurs at mainstem discharges of 23,000 cfs and greater.Base slough flow is maintained through intragravel flow and flow from Whiskers Creek.Whiskers Slough consists of a 520 foot long by 75 feet wide backwater followed by a series of pools and riffles. The substrate in the backwater is composed of thick deposits of silt/sand with the remainder of the slough being predominately deposits of rubble/large gravel with a layer of silt and some cobble (Appendix Figure A-5).The last 400 feet of the slough at the head is cobble/boulder.Three riffles are present which could inhibit fish passage.A more complete description of passage conditions can be found in Sautner,et al.1984 and Blakely,et al.1985. Evidence of upwelling is present in the upper pools,and bank seepage in the backwater area.The bank seepage along the right bank may be related to mainstem discharge (Appendix Figure A-6).Upwelling was not observed in the backwater due to the turbid water. Limited spawning occurs downstream of the mouth of Whiskers Creek and in the creek-slough interface (Appendix Figures A-7 and A-8).The majority of spawning in this site occurs in Whiskers Creek.The upper pools, while not utilized for spawning,are rearing areas for salmon fry.Open leads are present in these pools during the winter. It appears that the primary factors limiting spawning in Whiskers Slough are passage,siltation of the substrate and lack of strong upwelling. Slough 3B (RM 101.4L) Slough 3B is a 0.3 mile long side slough on the west side of the Susitna River at RM 101.4.The channel is approximately 40 feet wide consisting of two pools separated by a 20 foot riffle,approximately 740 feet above the mouth.The mouth of Slough 3A enters Slough 3B 320 feet from the head (Appendix Figure A-9).Substrate throughout the slough is rubble/cobble overlain by a thin layer of silt (Appendix Figure A-I0). In a breached condition,this site appears more like a side channel.In an unbreached state,severa1 riffles are present which may inhibit fish passage.The necessary local flows and/or discharge to alleviate these passage reaches are not known. The extent of salmon spawning in this slough is shown in Appendix Figure A-II.Barrett et al.1984 indicated peak counts for chum,sockeye and pink salmon at 56,20,and 28 fish respectively. Large substrate and lack of upwelling appear to be the factors limiting spawning in this site. A-6 ~, - ~,_e~l 1 j 1 1 1 "I 1 RM 101.0ED ZE o 250 I I FEET (Approx.Scole ) .r·.:~IV.·~·"· HI VER mWATER QUALITY MEASUREMENT SITE*INTRAGRAVEL TEMPERATURE SITE /SIJSI1NA SUBSTRATE TYPES S I·SILT;VERY FINE SA-SAND;FINE LG-LARGE GRAVEL;1.3" RU-RUBBLE;3 -5" CO-COBBLE;5_10" BO-BOULDER;>10" >-I-.s Appendix Figure A-4.Substrate composition and sampling sites in Slough 2 (RM lOO.2R). SUBSTRATE TYPES SI ~SILTj VERY FINE SA·SANDi FINE LG·LARGE GRAVELi 1-3" RU-RUBBLE;3-~" CO-COBBLE,e -10" BO-BOULDER;::>10" :t:> I 00 (§j ~ ~sus/rNA ..' i.;l\.'dr·.!"...·l\·\·,'J/....;·:!;·;·j····-..~·:· R/VER--- Slough 38 •J ,J .J ;J I j )J j I B Appendix Figure A-5.Substrate composition of Whiskers Slo~9h (RM lOl.2L).,J J J ])._.OJ .._..]..-.-1 .j ·_··1 --] (!J WATER QUALITY MEASUREMENT SITE*INTRAGRAVEL TEMPERATURE SITE PR PASSAGE REACH .-.-SEEPAGE ~UPWELLING Slough 38 ~~""'-' EBRM 101.4 ~.., R/VER--- .,.j ~,(•• -<sus/rNA <fJ )::- I \.D Appendix Figure A-6.Upwelling areas and sampling sites in Whiskers Slough (RM lOl.2L). Slough 38 (BRM IOJ.~'" .... ":.. '\-.~.·~·..:.;'.if.~,...~'L.~~•. R/VER-- PINK,1982 PIN K I 1984 CHINOOK.1984 ~ ~ mm~ SALMON SPAWNING AREAS :.:J~t·;·/<';~:"'····"~~:·.;:.....~~.:::.i~...':i'.'..:..~~i'.j:..i...."';'2,.,:'.'J •...;j..:~.•.•:•..,.• --E SUS/rNA .,..'..""."".,,J'Y',,·.,......• •,.,.'••~d'."F'Cr U ~.•••., ...;.'r .1-\"0 ..~.' ,'.'c;c;.'. .;/'~.s> /,,'-J :~" i'"";';:~~ }~:::.'" <f} ;-t:> I I-'a Appendix Figure A-7 .Pink and chinook salmon spawning areas in Whiskers Slough (RM lOl.2L). •l J ,~,J ~I )J I i -)J ~jf '--1 1 .~1 1 1 1 J -<sus/rNA COHO SALMON SPAWNING AREAS FBj 1983 II 1984 ~ I ~ ~ (Jj .r .,.;.r fJ \ ..:,," ,.:":):;~".','1''.. ":\~··':··;'·'ii:w:..·'!""'l·i'~",,.i~ '..',:...'to:,•~"'i·,oI?··,·,u;i·(.;itVd'··~ R/VER--- Slough 38 EBRM IO"I:~'~:., Appendix Figure A-B.Coho salmon spawning areas in Whiskers Slough (RM lOl.2L). .-.-SEEPAGE ~UPWELLING / -""'-- o 500 I I FEET (Approll.Scal.)<f] R I VE R ________ lIIIf Slough 3A -L sus/rNA ffiRM 101.5 )::> I I-' N :;.".•~;.:,;;,::::Yf:::.,.....:,'::,.~.'~'.:.:'':";":'.":"':;';"';":'.:.;.:;,.:;'.;T'~~;:;;'J"'':''-~'I:.,:.:"~';'.~::.'"....".;1 ..;,(':,.'.' .....::~•••".......-J"••':..'• •,".'.0"-..~~.-i' Appendix Figure A-g.Channel configuration and upwelling areas in Slough 3B (RM lO1.4L)and Slough 3B (RM lOl.4L)and Slough 3A (RM lOl.9L). j )~J J J J ~J J 1 1 J .~.~t -]§J l l '~--l 1 SUBSTRATE TYPES SI -SILT;VERY FINE SG-SMALL GRAVEL;1/4-1" LG-LARGE GRAVELi 1_3" RU-RUBBLEi 3_5" CO-COBBLEi 5_10" /-OVERLYING LAYER ~--- o ~oo,I FEET (Approll,Scole)~ R/VER ______ 01(Slough 3A SUS/TNA~- (BRM 101.5 )::- I I-' W :;,_,~',~,;,_,),::~.~r::";'.,,,'/':;,~,I.:p.~".:';.-;:T'\:;':'j'.':'";.':1'.:.,:.;;':~...:I.;1··..~,~::•••,,.i."f ~'\:",...~":.F.,..•. Appendix Figure A-IO.Substrate composition of Slough 3B (RM IOI.4L)and Slough 3A (RM IOI.9L). Slough 3A (RM 101.9L) Slough 3A is an upland slough flowing into Slough 3B,originating in a marshy area on the west side of the Susitna River.The backwater area extends approximately 200 feet upstream of the mouth to the confluence of a small left bank tributary draining a bog (Appendix Figure A-g).A thick layer of silt/sand is found in the backwater area.The next 1,000 feet of the slough is a 6 foot wi de channel compri sed of a seri es of shallow pools and riffles with rubble-large gravel substrates covered by a thin silt layer (Appendix Fi~ure A-10).Upwelling and bank seepage is present throughout this reach (Appendix Figure A-9). A 300 feet long and 15 feet wide side channel,1,200 feet upstream of the mouth,connects Slough 3A with the mainstem.Silt,covering rubble-cobble substrate,predominates in this channel.Upwelling was observed along the right bank near the midpoint of the channel.No fish were observed in this channel.At high discharges,the head of this side channel is breached. A long pool,which terminates in a beaver dam,is located upstream of the confluence of the slough and side channel.The pool appears almost stagnant with little perceptible flow.Some bank seepage from a bog area is evident along the left bank.Thick silt,organic debris and aquatic vegetation cover the bottom of this pool.The area appeared to be a rearing area as numerous fry were observed,even in the presence of low dissolved oxygen readings (2.5 mg/l). Upstream of this pool,the slough is a marsh maintained by a series of beaver dams.Chum and sockeye salmon were observed spawning within 50 feet of the base of the first dam.Salmon spawning areas observed during 1984 are presented in Appendix Figure A-II.According to Barrett et al.1985,the peak survey counts for sockeye,chum,and pink salmon were 11, 17,and 36 respectively. Passage,substrate,and widely fluctuating dissolved oxygen levels in parts of the slough,appear to be the factors limiting spawning. Slough 4 (RM 105.2R) This is an upland slough on the east side of the Susitna River.Prior to the summer of 1984,it consisted of a large beaver pond maintained by a 12 foot high 100 foot long beaver dam 100 feet upstream of the mouth. In 1984,this dam was opened to observe if salmon would utilize the newly available habitat.After removal of the dam and subsequent drainage of the pool,the slough was reduced to a 3 foot wide channel meandering from the mouth to the railroad bridge 1/4 mile upstream. Upstream of the rail road bri dge a seri es of beaver dams and ponds is sti 11 present.The observable substrate is si lt and sand with 1arge amounts of organic detritus.Large gravel/small gravel substrate is evident in the vicinity of the ARR tracks (Appendix Figure A-13).This may be a natural occurrence or as a result of railroad work.There is no evidence of upwelling or bank seepage in Slough 4.There is no history of any spawning activity due to the beaver dam blocking passage. Salmon fry were observed in a pool at the base of the dam.Upstream of A-14 - """ '"""" - - ""'" }l -}I -}---·1 ,,} <f}o 500 I I FEET (Approx.Seolt) SALMON SPAWNING AREAS ~SOCKEYE.1981 ~SOCKEYE.1983 ~SOCKEYE,1984 IIID CHUM,1984 1m PINK.1984 Beaver Dam R /VE R ________ ..c SloUflh 3A sus/rNA-( EDRM 101.5 )::> I....., (J1 :.;.~,'.;.-. .""::~":;:'~'"...y.:!.~.'.~':';'':i\:.,:.;>-..,'.::.:;",:••:",';.~:~:i·,;l'";?::,:J.;'(-,-~",',:.::,;.;.'~:~'" Appendix Figure A-II.Salmon spawning areas in Slough 3B (RM IOI.4L)and Slough 3A (RM lOl.9L). o WATER QUALITY MEASUREMENT SITE lie INTRAGRAVEL TEMPERATURE SITE --- :":'~'";.2,i o 500 I I FEET (Approx.Scole)<fJ Beaver Dam Jlo". ~.- \",.'............•,.\' RIVER _______ ....Slough 3A sus/rNA--'--. ffi RM 101.5 .,'.jl::> I' I-" Ol ;7."':>',..;,:;:..,?::;':':':i';~,~.~:r.~::,':':'":.-:.;.:~..::,:;,.:.",.:;..~:':;":t'~~::::!,"~"(,~.,,.;;,':;''':''.'"':':'••\~i Appendix Figure A-J?.Sampling locations in Slough 38 (RM lO1.4L)and Slough 3A (RM lO1.9L). .~}~.)I I J l 1 t ,.i I ~.•~,,J )I )1 •••¥..,;;.'•.;;.:T.".,a·.i ~'I••;:-. ::..."!.f'"J j j',';';'J.-'.--:'•• o 130 1 I FEET (Approll.Seo Ie I ~RM 105,5 ~...i\1t"'.,-.I;"il;.-•.S~'.:4.!:~.'r~«.:ci: <E S I ~SILTj VERY FINE SA-SANDi FiNE LG-LARGE GRAVEL i 1-3" RU-RUBBLEi 3-6 11 CO-COBBLEi 5-10" I .OVERLYING LAYER <.J.:;:.....,1.'·:/:,,;~::....,...",. •-..,-i;.....:.;...~'-.....i··!·'··,·· ...:.11......SUBSTRATE:TYPES ,.....,t.t;;·...:··· r~tT••\~;··:···• RIVER ---- [!]WATE R QUALITY MEASUREMENT SITE*1NTRAGRAV E L TEMPE RATURE SITE ~SLJs,rN/l ,...'f.'.;.;:'::::i':l:;'" .......:•.!')::;> I....... -....J Appendix Figure A-13.Channel configuration,substrate composition,and sampling sites in Slough 4 (RM 105.2R)• the dam,only three spine sticklebacks and numerous insect larvae were observed. Passage,substrate and lack of upwell ing appear to be the factors limiting spawning in this site. Slough 5 (RM 107.6L) Slough 5 is an upland slough,approximately one mile long,entering the mainstem Susitna River on the west side at RM 107.6 and consisting of a series of long narrow beaver ponds.The first beaver dam,1,500 feet upstream of the mouth,effectively restricts further upstream migration of fish.Below this dam the slough appears to be a long narrow run with cobble boulder substrate covered by a thin layer of silt.The water is stained brown du~to dissolved organic compounds filtered out of the bog,which appears to be the main source of water for this slough.A sand bar at mouth of the slough may prevent passage at lower mainstem discharges (Appendix Figure A-14).There was no evidence of any upwelling or bank seepage in Slough 5,and although there was limited spawning present in 1982 and 1983,none was evident in 1984.Although none were observed,the marshy area may be util ized as a reari ng area for juvenile salmon.The aquatic vegetation provides excellent cover. This slough has numerous deficiencies as a spawning area and should be left as a possible juvenile rearing area. Slough 6 (RM 108.2L) This is a 1.S mile long upland slough,originating in a bog with numerous beaver dams and ponds,located on the west side of the Susitna River at RM 108.2.The water is stained brown due to dissolved organic materials.A beaver dam,located seven hundred feet from the mouth,is a complete passage barrier (Appendix Figure A-IS).Upstream of this dam is a large and complex series of dams.A backwater area extends approximately 50 feet into the slough,followed by a 200 foot shallow riffle.A straight run extends above the riffle to the beaver dam. Substrate in the backwater is silt/sand while the rest of the slough tends to be cobble/rubble (Appendix Figure A-16).Limited bank seepage was observed along the left bank.Spawning has not been documented in Slough 6. This site has numerous deficiencies as a spawning site and is best maintained as a possible rearing area. Oxbow I (RM 110.lL) Oxbow I is a 100 foot wide by 0.5 mile long side channel at RM 110.1.A small creek draining a bog,enters the left bank at the midpoint of the slough.In an unbreached condition,three large pools exist in the upper section of the slough and a backwater area in the lower section. Substrates are predominately cobble/boulder.But,areas of large gravel/rubble substrate can be found throughout the site.In the backwater,silt/sand deposits have accumulated up to two feet thick (Appendix Figure A-17).Three riffles are present which may inhibit fish passage,depending on mainstem discharge.The base water source A-18 - ..- :t::o I...... \0 )1 o 300 I I FEET (Approl.Scoll) ~ --') o WATER QUALITY MEASUREMENT SITE If!INTRAGRAVEl TEMPERATURE SiTE .r_·"":~I'.L:.''l.~••,.._~·i-&,.··:"l.L\;.:,,·~.,,--(!'~M;,,·~·l:J ~.':.'l" "\V SUBSTRATE TYPES S 1-Sil Tj VERY FINE CO-COBBl E j 5 -10" B0 - B0 Ul 0 E R j :>10" /-OVERLYING LAYER ~..•)~... EDRM 108.0 ---...I ""SUSI rNA RIVER ----- Appendix Figure A-14.Channel configuration,substrate composition,and sampling sites in Slough 5 (RM l07.6L). o 2~O I I FEET I Appro •.Scoll) ~SEEPAGE [!]WATER QUALITY MEASUREMENT SITE*INTRAGRAVEL TEMPERATURE SITE )::a I N a <] ~Sl/s/rN4 RIVEN E9 RM 108.5 Appendix Figure A-15.Channel configuration,bank seepage,and sampling sites in Slough 6 (RM l08.2L). .~}:I )_I .~~),§,.B J ..I ~)I J j -1 J ],J --l -1 ~St/SlrN4 }» I N...... o 2~O I I FEET (Approx.Scal.) <J] SUBSTRATE TYPES S 1-SIL T,VERY FINE RU-RUBBLE,3-5" CO -COB BL E;5 - I0 " RIVEN $RM 108.5 Appendix Figure A-16.Substrate composition in Slough 6 (RM l08.2L). .r~~·,·n;·\·:oJ,·'h~u~!f,\::iA~f?;"ftx:·~....t~~·..~lr.\c:o;.~"I:!\.:r{"~f'"I':f.7~·"'·~"\~~r.-';~':i':.'~'1A'i~~'.f'"u,~-.:,~"I:· / ~E,~ ~\ SUSlftJfl iiIII(-- ..........SEEPAGE ~UPWELLING<t1 o 500 I I FEET (Approl.Scal.) eRM 110.0 ::t:> I i'U N Appendix Figure A-I?Up~elling and substrate composition in Oxbow I side channel (RM 110.0L). )J J J I ,,J l 1 t J j i J ))J r- I I -I appears to be the surface inflow of the small creek and seepage from both banks in the lower portions of the first pool.Mainstem water may also flow intragravelly through the head during unbreached conditions. The pools near the head have open leads during the winter,but no upwelling was observed. The only recorded spawning in Oxbow I Side Channel occurred in 1984, when chum salmon were observed spawning in the backwater area (Appendix Figure A-18). Problems inhibiting spawning appear to be passage at low mainstem discharges,substrate and lack of upwelling.Overtopping in winter may inhibit incubation,thereby limiting spawning potential. Slough 6A (RM 112.3L) Slough 6A is an upland slough,draining a marshy area,approximately one mile long on the west bank of the Susitna River at RM 112.3. Approximately 1,000 feet upstream of the mouth of the slough,a beaver dam complex acts as a complete passage barrier (Appendix Figure A-19). A tributary enters the slough on the left bank approximately 500 feet upstream of the mouth.The water of both the slough and tributary is stained brown due to dissolved organic compounds.The reach from the mouth to the dam appears to be a backwater with imperceptible flow.The _substrate is covered with deep silt/sand and decaying organic matter. Immediately downstream of the dam,the silt thins and cobble/boulder substrate can be seen.Areas of large gravel/rubble substrate can also be observed along the left bank,downstream of the tributary.No spawning was observed.in Slough 6A in 1984.Fish observations made in Slough 6A were of milling fish. Substrate and lack of upwell ing appears to be the factors 1imiting spawning.At present,the site is best left as a possible juvenile rearing area. Slough 7 (RM 113.2R) Slough 7 is a remnant side slough on the east bank of the Susitna River adjacent to the ARR tracks.The slough is approximately 500 feet in length,comprised of two pools separated by a narrow,short channel.A silt/sand bar across the mouth severely·restricts passage into the slough at most discharges (Appendix Figure A-21).Silt deposits approximately 4 to 5 feet deep are found in both pools with cobble/boulder deposits located between the two pools and at the head. Limited upwelling occurs along the left bank and is most likely related to mainstem discharges.No documentation of salmon spawning in Slough 7 exists. Slough 7 appears to be a remnant slough of little use.Passage, substrate and low pH appear to be limiting any spawning. A-23 -./.•.•~.:,.~...·,~'':'.r:!I'lI •.::.~•.l":r;:.i·:-~~...~4.:..;:.~.-"'!i'::\..::-~:ro.·:~~;.,{l"r't·:r;'i~."O";\~;;.~::,--:-"'~;~.\."tA.1.i / \j ~~ ~\ SlJS11l'1~ ......~... -<- .,~~~._.*04 ...:,..1 ::."0:'-.O;~ CHUM SALMON SPAWNING AREAS ~1984~ (!J WATER QUALITY MEASUREMENT SITE*INTRAGRAVEL TEMPERATURE SITE ~RIFFLE .,-'0':" ~!!'''''·.~r~~~.\i;'''''i;·t;···;';"'~··''':·····:··i·.·~·;,.i·~:;;~.·:":)':;'~ <t1 o 500 i I FEET (Approl.Scolt ) eRM 110.0 :t:o I N ,t:>. .Appendix Figure A-18.Sampling sites and chum salmon spawning areas in Oxbow I side channel (RM 110.0L). ,I J J J !J \J J ~,J J ,,1 )J 1 -1 --J -~---l '-~-,-1 '--~l 1 -"--1 1 );>0 I;-v l.11 o 250 I I FEET (Approll.Scali) <J] ••••~••~.....,...!"--.~,•:.•.,..'.......~r.'\"'..L••.')~o(~~..:::~Nt!aXtr~·Jf,·'''.J~",,'~rf..I'~.1t.:_.:J.•••• SUBSTRATE TYPES SI·SILT;VERY FINE LG -LARGE GRAVEL;1-3" RU-RUBBLEj 3·5" CO-COBBLEj 5-10" BO·BOULDERj 10" /.OVERLYING LAYER ____SEE PAG E ~UPWELLING E9 RM 112.5 &411(SUSI rNA RIVER Appendix Figure A-19.Substrate composition and bank seepage areas in Slough 6A (RM 112.3L). )::- I N O"l o 2~O I I FEET (Appro.,Scal,) ~ :\.l:-.(,~,.~_. ,..~t- r ....J'"f·;j'J',;,6 .'"~.0 .'p',"0"\J"5-j.' •.••~·I~·.."'~;'!:~'-V')'''::'':1~\.~,,:,..''.'>:'I<;'.1",::",;'~',~"'.;·'''~1!'.JI ..''"•·..•..~.;.u~,:~..:.h(:.,··· (!]WATER QUALITY MEASUREMENT SITE •INTRAGRAVEL TEMPERATURE SITE El)RM 112.5 ...,.SUSI rNA RIVER Appendix Figure A-20.Sampling locations in Slough 6A (RM 112.3L). J I }.J ),I J ))].~))t ~J ~~ 1 1 )~"'-l 'j Ef)RM 113.2 -.t sus/rNA R/VER <f] a 130 I ! FEET (Approx.Scole) [!]WATER QUALITY MEASUREMENT SITE*INTRAGRAVEL TEMPERATURE SITE ':,~1~t.y II},J:,I!/~~.~.e ..;.,~;,Q t:.';~'.".";"\,,'.d·<Q {(;/.•;.,".:~.iI',/.~'. ........:"Q b'::~••I.~,....•••,;,...P CJ /.:.~.;SI /,.'.-,.,.,..,..1'.1' d.'b ,.'RU -C0 "It' ,.•...,•...••, .L"".---.",""",,,,,,.,,.'..f;" SI .......:·.·:1 .•..•"~.0"gh .,.7 '.'"'r':.·I ~.."":'I.I...~~..,..".~:.....;.;..,.,.::.'t" SUBSTRATE TYPES S I -SILT;VERY FINE RU-RUBBLE;:5-5" CO-COBBLE;!5 -10" BO-BOULDER;:>10" /..OVERLYING LAYER ~SEEPAGE ~UPWELLING :;po I N ---J Appendix Figure A-21.Substrate composition t sampling locations t and upwelling areas in Slough 7 (R~1 113.2R)• Slough 8 (RM 113.7R) Slough 8,also called Lane Creek Slough,is an 0.5 mile long side slough adjacent to the ARR at RM 113.7R.Substrates appear to be rubble/cobble with sections of large gravel/small gravel in the upper reach and thin silt/sand deposits in the lower reach (Appendix Figure A-22).Extensive areas of upwelling along the right bank and surface inputs via a remnant channel from Lane Creek occur in the lower half of the slough (Appendix Figure A-23).A culvert under the Alaska Railroad channels surface runoff into the slough. A number of riffles exist which could possibly inhibit fish passage. The primary passage barrier at low discharges,appears to be a sand bar at the mouth.Backwater effects,apparently related more to a hydraulic plug caused by the creek discharge than mainstem discharge, will have a modifying effect on this passage reach but not those beyond it. Spawning occurs in areas associated with pockets of large gravel/rubble substrate as well as having evidence of upwelling (Appendix Figures A-24 and A-25). ~I At present,passage and substrate appear to be limiting spawning in this ~ site.Due to strong upwell ing and bank seepage,presence of areas of suitable substrate,and its close proximity to the ARR,this would be a good candidate for further study as a mitigation site. Mainstem Two (RM 114.5R) Mainstem Two is a one mile long V-shaped side channel located one mile upstream of Lane Creek (Appendix Figure A-26).The si de channel is separated from the mainstem Susitna River by a large vegetated island. The east and west channels are 4,400 and 2,800 feet long respectively and merge approximately 1,600 feet upstream of the mouth.The east fork has a breaching discharge of 25,000 cfs while the west fork breaches at 16,000 cfs.Downstream of the confluence of the east and west channel, Mainstem Two is a backwater area and a series of pools and riffles throughout both forks upstream.Substrate in the backwater area is deep silt/sand over boulder except in the extreme upper portions where there are pockets of rubble/large gravel (Appendix Figure A-27).The remainder of the side channel has well cemented cobble/boulder substrates with rubble/large gravel substrate in the pool areas.There is moderate bank seepage and upwelling from both banks in the backwater and in the east fork.During unbreached conditions,mainstem water may flow intragravelly through the head of both forks. Passage to upper spawning areas becomes a problem in an unbreached condition (Appendix Figure A-28).A complete analysis of passage into and within the slough can be found in Blakely et ale 1985 and Sautner et ale 1984.Mainstem Two historically has been a chum salmon spawning habitat.In 1984,the total peak count for the site was 134 fish.The extent of salmon spawning can be seen in Appendix Figure A-29. Passage,substrate and dewatering of redds at low mainstem discharges are the primary problems limiting spawning in this site. A-28 .. -, I'fl"', )-1 J 1 J 1 ] '''''~.''~:<·9.-.",,:iv3<'.t ..e•••,.=-- ••/~0L.!(-A-P-P"'~:"''I.E::-:.T::-S-~O-..I-'~~)?: ".·.:..,,·...'':.I·•.,\:'!~......'·A •.;••..••••!l:~;_••.!'••_'.1'"1::_•••'........,... (f)RM 114.0 ••U.i":.·,;...···\·.i"'{...':i';. RIVER •....;..i'{·.i:·I.'·~ RAILROADALASKA Lons Cr••k SUBSTRATE TYPES 5 1-SIL Tj VERY FINE -SUS I TN A SG-SMALL GRAVEL;........... 1/4 -I" LG-LARGE GRAVELj I-3" RU-RUBBLE;3-5" CO-COBBLE;5-10" / -OVERLYING LAYER :r.-:a I N lD Appendix Figure A-?2.Substrate composition of Slough 8 (RM 113.7R). o ,300 I ! FEET (ApprOll,Scole)....'_ .J"". EDRM 114.0 .,-~'i'A~/''y .::',....,''.,",',"""'""'.....'n;;""'"...:"",;,.•6. .•>~W.'.~\~'~>"'';:I\-!''_.t.3 ......... ~RIFFLE .....-sus/rNA -+-SEEPAGE ~UPWELLING R/VER ):::> I Wo ".~'i~'"......'1',0.<';.,.~ Appendix Figure A-23.Upwelling and bank seepage areas in Slough 8 (RM 113.7R). I ))I I I ~)-)))•)l ,I ~J J --,1 -,--1 -)-')"-~'~l ~_~l J E9RM 114.0 ,r~0 3001I•~FEET<.11 1,,"0'.Scol.) ...............,•.,•.I!,.•.t.••,."••,:...~••••:.::i.:•.;;1;......t:.. CHUM SALMON SPAWNING AREAS ~1981 mID 1983 mEl 1984 ~--SUSI TN A ~RIVER > ! W t-' ALASKA RAILROAD Appendix Figure A-24.Chum salmon spawning areas in Slough 8 (RM 113.7R). EDRM 114.0 l:/ l ~?L;-A-P-P-=~-;:~K-;:~-:;~'--~-.~-.~,-.~...;,~< "'.'.•'.I ',.\~I ~~.1"•.~.~:~..:~'~:'l::.':.j.~r :',:"r.'.•':..':'' . R/VER ---_ ...;...,.;.:.;:;("~~'~f:~;::::;<...;.~.:,~:•.... ";;b .i";:~:i'~.~,":V'''.''-~~:;-;;;.;-;:..:.""~".;-;;:..•.;~,}.::'J;~::...,.;::_."'~:, ......-sus/rNASALMON SPAWNING AREAS IIIIl SOCKEYE,1983 ~PINK,1981 [!]WATER QUALITY MEASUREMENT SITE*INTRAGRAVEL TEMPERATURE SITE):> i W N ALASKA RAILROAD Appendix Figure A-25.Sockeye and pink salmon spawning areas and sampling locations in Slough 8 (RM 113.7R). I •J J J "' })J )$J J !J ,J )1 1 1 1 1 -1 o 620 I IFEET (Approx.Seole) 1JJ [!]WATER QUALITY MEASUREMENT SITE*INTRAGRAVEL TEMPERATURE SITE ~SUBSTRATE SAMPLE SITE lID DATAPon SITE RIVER ____ *@I~. ~.':•.··.·.r.-.•.·,':'._.: ~:,',t"\.J.~\.;:!h ~••~..~,,~.\.!:t~~i:':'''_::,:,;'~,:.n..~_".')..\..'.'J!~" E9RM~Sl/S/TNA~<;••;.;;;i";,,,:.:.•.{":"""~':"•.'...'~"_.~'~.'. >I W W Appendix Figure A-26.Channel geometry and sampling sites in Mainstem Two Side Channel (RM 114.5R). o 620 I .I FEET (Approx.Scale) ~ SUBSTRATE TYPES SI -SILT;VERY fiNE RU-RUBBLE;3-5" CO-COBBLE;5_10" BO-BOULDER;>10" /-OVERLYING LAYER ~SEEPAGE ~UPWELLING ):;> I W .j::o ~..:.•...,'.;.,';,':;"""";" _\"'~"':';':"i~'l""','''''id''';'i't;'''';''::l)'·":'·;\"i':;l:'jiti;';;';"";''''''~ EBRM ~S{jSlrNA ~,,~_,u RIV£R___.... Appendix Figure A-27.Substrate composition and bank seepage areas in Mainstem Two Side Channel (RM 114.5R). J i ]t ),I )),•J I ~J )J .,} 1 1 J 1 1 ...".1 ---, o 620 I IFEET.. (Appro •.Scale) -PR PASSAGE REACH ~ RIVER ____ ~,~'.I"U'.~\.:1 f J,~*.~..~,......!~l:'1..••!1...,:~!:,.l:. (BRM ~SllSlrNA........tt......~.. » I W U1 Appendix Figure A-28.Passage reaches in Mainstem Two Side Channel (RM 114.5R). ~, - - - - - SIDE CHANNEL SITE RM 114.6R SIDE CHANNEL SITE RM 115.IR ___......,.SIDE CHANNEL SITE RM 115.0R ,~ '1 ",', " ,~ ,; ", 't, ~.. ·t".. "!~. - RM 115.0EB ~CHUM ~SPAWNING AREA 82 - CHUM <-II SPAWNING t't'\ AREA 83 ~ ~CHUM SPAWNING AREA 84 ~ a 500 I I I FEET (ApprOll.Scale) Appendix Figure A-29.Chum salmon spawning areas in Mainstem Two Side Channel (RM 114.5R). A-35 ,...., Bushrod Slough (RM 117.9L) This is a 2,000 foot long S-shaped side slough on the west side of the Susitna River at RM 117.9L (Appendix Figure A-30).The slough is composed of a bedrock based backwater area foll owed by a pool riff1 e sequence.The head is a cobble-boulder berm.Substrate in both pools is primarily large gravel/rubble with the upper pool containing a greater percentage of si 1t and havi ng a greater degree of cementation than the lower pool.The riffle between the two pools is primarily well cemented rubble-cobble substrate (Appendix Figure A-31).A small tributary,draining a bog area,enters the left bank at the mouth.Four foot high banks border both sides of the slough. In the 9,000 cfs to 12,000 cfs range,the backwater is tannin stained to clear,indicating a greater slough influence than mainstem.At mainstem discharges above 12,000 cfs the backwater is turbid.Upwelling and bank seepage seem to be the driving hydraulic force in the slough in an unbreached state (Appendix Figure A-31).The limited right bank upwelling and bank seepage in the upper pool appears more directly related to mainstem discharge than an independent groundwater influence. As mainstem discharge drops in the fall,upwelling stops and the pool will gradually dewater and freeze prior to the river staging •.The lower pool is greater than 3 feet deep in places and appears to be maintained by upwelling and bank seepage.While upwelling was only visible along the left bank,it is strongly suspected that it is present along the ri ght bank as is evi denced by the presence of an open 1ead,temperature data and spawning activity. In the 9,000 cfs to 12,000 cfs range,two major passage problems exist, a 50 foot riffle that separates the backwater from the first pool and a 175 foot riffle separating the two pools (Appendix Figure A-32).The passage restriction at the riffle between the two pools is prevalent during unbreached conditions while the passage restriction at the mouth becomes evident only below 12,000 cfs. According to Barrett et a1.1985,peak counts of 10 pink salmon and 90 chum salmon were observed in the slough.Chum salmon spawned extensively throughout th~lower pool and did not uti 1ize the upper pool,even when passage was possible during breached conditions (Appendix Figure A-32).Chum salmon were first observed spawning in this site during 1984.Fry were observed in both pools during 1984. Numerous chum salmon fry,from 1984 spawning,were observed in the lower pool during the spring of 1985. Problems limiting spawning at this site are passage,substrate and limited upwelling in the upper pool. Curry Slough (RM 119.7R) Curry Slough,a former side channel located on the east side of the Susitna River,is approximately two miles downstream of the Alaska Railroad (ARR)Curry Station.The ARR constructed a 10 foot high berm across the head to prevent erosion of the ARR tracks that parallel the right bank of the slough.This berm,which prevents overtopping of the A-37 o 320 I j FEET (Approl.Scale) ~ [!]WATER QUALITY MEASUREMENT SITE *INTRAGRAVEL TEMPERATURE SITE I;;J SUBSTRATE SAMPLE SITE )::> I W 00 $RM 117.9 "Il(sus/rNA R/VER Appendix Figure A-30.Channel geometry and sampling locations in Bushrod Slough (RM 117.9LL ~.,.~J J ,t .~~I J )I I .~))~ 1 }1 1 1 )1 1 )1 )'--1 ~ I W l.O o 320 I J FEET (Approx.Scole l ~ SUBSTRATE TYPES SG -SMALL GRAVEL;1/4 -I" LG -LARGE GRAVEL;1-3" RU-RUBBLE;3-5" CO-COBBLE;5-10" 130-BOULDER;>10" .......-SEEPAGE ~UPWELliNG lID DATA POD SITE LG -RU -SG EDRM 117.9 ~sus/rNA R/VER Appendix Figure A-31.Substrate composition and upwelling areas in Bushrod Slough (RM 117.9). );;:0 I +>o a 320,I FEET (ApprOll.Scole ) ~ SALMON SPAWNING AREAS ~CHUM,1984mnPINK,1984 ~RIFFLE ,~.""",...~;,;I,I"I,;,~i"·'i,-;:.:••~~"1'·'7""~'··"·'" ....:i:,'<I.<rd!..,e,;_'-i\i ••,iJ..;\'.},,~.'JI"..,~,~41 .:,,;.: .:\..._...,_.!•.J,)o.l..,\• El)RM 117.9 ~SUS/rNA R/VER Appendix Figure A-32.Chum and pink salmon spawning areas in Bushrod Slough (RM 117.9). ~J ~I J ••J I J J ,I »-~J ,J ~~ -~-1 1 1 ]'i '----.~!l!l!; -~-)J '~1 ]1 )::> I .j:::o I--' o 320 I J FEET (Approx.Scole I ~ •STANDPIPE SITE a NUMBER _•.:'..~:I_'·•.J~·'!..'"' E!)RM 117.9 -..(SUSlrNA RIVER Appendix Figure A-33.Standpipe locations in Bushrod Slough (RM 117.9L). head,cha nged the characteri st i cs of the site to those more closely associated with upland sloughs. The right bank is a 10 foot high embankment that serves as the roadbed for the ARR.The left bank is a low lying vegetated gravel bar.The slough is a 600 foot long run followed by a 700 foot long pool.Three riffles are present at the mouth,between the run and pool and from the head of the pool to the berm (Appendix Figure A-34).The substrates throughout the site are primarily rubble/cobble covered by a layer of silt that may reach up to two feet thick in places (Appendix Figure A-35). At low mainstem discharges,the lower run dewaters indicating it may be directly related to changes in mainstem discharges.The pool habitat, which is 3 to 4 feet deep in places,is apparently maintained through upwelling and bank seepage occurring at the head of the slough (Appendix Fi gure A-35). During 1984,a peak count of 8 chum salmon were observed in this slough (Barrett et al.1985).This is the first observed use of this site by chum salmon with two redds resulting (Appendix Figure A-34).Fry have also been observed throughout the site. Problems limiting spawning in this site are passage (primarily from the mouth to the base of the upper pool)and substrate (large substrate and excessive siltation). Slough 8C RM 121.8R) Slough 8C is a 1,600 foot side slough on the east side of the Susitna River with a low lying head that is frequently breached.A small clear water creek enters the right bank of the slough about 300 feet from the head.Upwelling is present in the proximity of this creek as well as in the upper third of the slough (Appendix Figure A-37).The lower half of the slough is a turbid backwater at most discharges.The substrate throughout this slough is a fairly uniform rubble/large gravel covered with a thin layer of sand.Large gravel/small gravel deposits exist in the upper half of the slough.A silt/sand bar becomes evident in the mouth area at low discharges which is the only apparent potential passage problem (Appendix Figure A-38).At this time a 100 foot riffle forms which may be restrictive to passage~ All spawning that has been noted in Slough 8C has been in close relationship to the areas of upwelling (Appendix Figure A-39),primarily in the upper half of the slough.Limited spawning also occurs along the right bank in the lower half. Problems limiting spawning are passage at low discharges,substrate,and limited upwelling. Slough 80 (RM 121.8R) This upland slough enters the mainstem Susitna River immediately downstream of the mouth of Slough 8C.It runs roughly parallel to the A-42 -I - ~, )1 1 1 'J 1 '-0'1 11 J ]-]1 1 o 2S0 I I FEET (Approl,Scale) ~ ..----SlJS1fN/l R,yf R ----EBRM 1.20.0 ~.:~H';'-."'Il OW-~,....,..'",'r, ~..-.'" ..f:-"-':~#<I'. CHUM SALMON SPAWNING AREAS ~19S4 ~----2 mlIE ~..-,.- Curry Slough ."..,... • I ~."'-I ...•••••\.!'.•,_••'•.."A'\,.'.~_~"_.J-,,*I..'rL~'~••••••..I ~''"~.•I o WATER QUALITY MEASUREMENT SITE*INTRAGRAVEL TEMPERATURE SITE ~SUBSTRATE SAMPLE SITE [Q]DATAPOD SITE •••,,",,.,.......I ,.'",.F'.'j:'· ~ I -I':>w Appendix Figure A-34.Channel geometry,sampling locations,and chum salmon spawning areas in Curry Slough (RM 119.7R). o 250 I ! FEET (Approx.Scolt) <fJ .----suS 1rNA RI Vf:Fl ------ SUBSTRATE TYPES 51-SILTj VERY FINE LG·LARGE GRAVELj 1-3" RU-RUBBLE;3-5" CO-COBBLEj 5-10" / -OVERLYING LAVER EBRM 120.0 -.-.SEE PAGE ~UPWELLING ~ I .po. .po •"~T :...'!.1";.·.·,.........""J;"t6r..~ ....,".,'..•...•,~... ,;:'.....1......~Curr v SI.....•,_,...;'..,.....ougn ........."'I -:,.00 " •~ft.01 , • ".•.:~:'\.RV-LG ".'..0't','•",.~,......0·...If'. Appendix Figure A-35.Substrate composition and upwelling areas in Curry Slough (R~1 119.7R); "I J 5 J J ~~,J J J !J i ~)I ,J 1 1 ~}1 1 1 1 o 2~0 I I FEET (Approl.Scola) ~ .------5 tJ S f r N.A I'll V E:R ------EBRM 120.0 10- :-...ue ;...... 9-8- .......-~••I:'~.-...~',1 .~ •••••••••~"-..._.......\.....t'l.•.t_,. 7_ 6- ..·iiI.~·:..,..ql... 5_.,,....:~......\... Curry Slough •I.'!"""i.'.•.1•••4,1,:••••••2e Ifl '....,I;···,.....t;~"·'.lo ..!.:..~J".. 4_ I. ~~ ............'..'..-."..,..•.:P- I .j::> U1 •STANDPIPE SITE a NUMBER Appendix Figure A-36.Standpipe locations in Curry Slough (RM 119.7R). ._~""" <E ••o-t!',"·w r·-'··l''':'"?'il~...,;o.~•••\'."f"~~1 o 400 I I FEET (Approl\.Scole) .;,.....~...'e'"i~{t..,..•••t"~..~.II":I·'·;i ;".•~~-~'..-..,.: ,;--t'·6§~~1'.rUlli·••_, ...·.·0·.-.···,. -.-SEEPAGE ~UPWELLING ~RIFFLE EB RM 122.0 RIVER ~ -.,r ..",'...---w '.i'il'~....••_ SI h 80 ,......,,t.,..It.oug ._.\~. •#·_···..'O':"·.i',·,'"Jlrt,')<,.:w,~ ~ ~sus/rNA ~ ALASKA RAILROAD :> I -I'> CJ) Appendix Figure A-37.Channel geometry and upwelling areas in Slough 8C (RM 121.8R)and Slough 8D (RM 121.8R). I i I J ~J ...j t )~J ~I J J J •I C~l ))J 1 1 l ]1 l ••J":,~";':r·-",-:--......-".ji _.- $ .~"~.\I" '~"·ol~t;"fi_..~_...·oi o 400 I I FEET (Approx.Scale) SUBSTRATE TYPES 51·SiLTI VERY FINE SA -SAN 01 FINE SGwSMALL GRAVELII!4-1" LG -LARGE GRAVELl i·3" RU-RUB B LEi 3 -~" CO-COBBLEI ~-IO" ! -OVERLYING LAYER ED RM 122.0 RIVER .....,t....,..'. ~SUSITNA ~ ALASKA RAILROAD SA-SI ~ I ~ -....l Appendix Figure A-38.Substrate composition in Slough 8e (RM 121.8R)and Slough 80 (RM 121.8R). 'i,·~~·;:'\T;'lr,-=~ ~ •·"-~\"'r:'-...-~-. o 400 I I FEET (Approll..Seol.) CHUM SALMON SPAWNING AREAS ~1983 ~1984 "l-. E9 RM 122.0 R/VER @ WATER QUALITY MEASUREMENT SITE*INTRAGRAVEL TEMPERATURE SITE @*2 sus/rNA ·1[.JiI'......._.a .... ~~,;........."••i:4':1:r: ALASKA RAILROAD ):> i -P>o OJ Appendix Figure A-39.Chum salmon spawning areas and sampl ing locations in Slough 8e (RM 121.8R) and Slough 80 (RM 121.8R). !D )J cJ ,)~1 1 J i .J I I .~J 1 ).~ 11"I10~ r I 1""'\ I Alaska Railroad for approximately 0.4 miles before crossing the tracks (Appendix Figure A-37).The channel is approximately 15 feet wide,with thickly vegetated banks providing good cover for juvenile fish.Many fry were observed in Slough 80 during the open water surveys. Substrates are large gravel/rubble/small gravel with some silt and sand accumulations,especially at the mouth (Appendix Figure A-38).The sand bar at the mouth causes fish passage problems at low mainstem discharges.The lower half of the slough was the primary chum salmon spawning area in 1984 (Appendix Figure A-39).Although upwelling wasntt observed in this site,it is probable that it is present as open leads were observed durin~the winter. Problems limiting spawning at this site are minor passage restrictions at the mouth during low discharges and possible substrate. Slough 88 (RM 122~2R) This is a 1.6 mile side slough beginning at RM 122.2 on the east side of the Susitna River.Intermittent side channels connect the slough with the mainstem.Breaching discharges for these channels have not been determined.The only observed upwelling or bank seepage was found in the backwater area of the mouth (Appendix Figure A-40)but may be present in other are~s of the slough,as evidenced by open leads in the winter.Observations of upwelling were hindered by turbid wateror lack of silt to mark water movement.Generally,downstream of the confluence of the two channels,substrate is predominately silt over rubble/cobble, while the right channel is rubble/cobble/large gravel (Appendix Figure A-41).Passage restrictions are numerous throughout the slough.Large areas of Slough 8B are used for spawning by chum and pink salmon (Appendix Figure A-42). Passage appears to be the primary 1imiti ng factor to spawni ng in thi s slough.. Moose Slough(RM 123.1R} Moose Slough,a 2,000 foot long side slough,is located two-tenths of a mile upstream of the head of Slough 88.It is a narrow channel with a backwater in the lower one-half and a run in the upper one-ha 1f.Deep accumulations of silt and sand occur in the backwater area.The upper section is large gravel/rubble with some cobble occurring,primarily in riffles (Appendix Figure A~43).A low gravel bar separates the slough from the mair'1stem on the left bank. Extensive upwelling and bank seepage occurs throughout this slough (Appendix Figure A-44).The left bank upwelling appears to be the result of mainstem intragravel flow,while that on the right bank is probably independent of mainstem effects.At low mainstem discharges, the channel dewaters except for isolated pools and a small backwater area,creating passage problems for fish.The majority of spawning occurs at the upper end of the backwater and upstream (Appendix Figures A-45 and A-46). A-49 ::P I CJ1a o 500 L I FEET (Appro •.Scale) ~ EBRM 122.2 / 5t151-rtJ~ /~1'/f:fl ,J....1'S·t~'\l <)~ (!]WATER QUALITY MEASUREMENT SITE *INTRAGRAVEL TEMPERATURE SITE O~<;) \\,,~~\)- ",~'f.~ ~\"r Appendix Figure A-40.Channel geometry,upwelling areas,and sampling locations in Slough 8B (RM 122.2R)• J J J .~J ,~J 1 J ~~,~~1 !~J ~~~-1 .1 -0-1 -_....'] ~~,,,~~ SUBSTRATE TYPES .S I •SILTi VERY FINE 5G-SMALL GRAVEL;1/4-I" LG-LARGE GRAVELj 1-3" RU-RUBBLEi 3.5" CO-COBBLE,5-10" BO-BOULDERi>IO" I -OVERLYING LAYER .sIJSI1'~P. / CO-RU .~.,"r.lj:"VI~.f)l:t'l\:r':,,'..'a...i")"".'0',..,..........·-· ~ EBRM 122,2 o 500 I IFEET (Approll.Scole) )::0 I U1....... Appendix Figure A-41.Substrate composition in Slough 8B (RM 122.2R). EBRM 122.2 a 500I, FEET (Approll,Scale) Ot>-Q \"'~~t>- ....CO't-t>- t>-",r SALMON SPAWNING AREAS ~CHUM,1983 ffdJ CHUM,1984 •PINK,1984 ~~I"e:~ SlJS1fl'l/l ~.'•.. / ~ ........._. ,~, ~. i1: :! .. "" "" ~ »> ! 01 N Appendix Figure A-42.Spawning areas in Slough 8B (RM 122.2R) j D J I J J J I .~.1 §,1 •• J I J ).1 1 (:'\...;_.,. ~J ~~-'l ._.~_'.,.~0;•• "!l.••l\".!c.-t ...:.~_,..:..1./ ~SUSlrNA 1 RIVER~ o 320 I I FEET (Approx.Scole) "1 ):>- I (}1 W !-',;,)h"'fL'W""""", Appendix Figure A-43. SUBSTRATE TYPES 51 -SILT;VERY FINE SA-SAND;FINE LG -LARGE GRAVEL;1-3" RU-RUBBLE;3-5" CO-COBBLE;5-10" Substrate composition in Moose Slough (RM 123.1R). EBRM 123.5 RIVER ~ p._1 .'.••.'Lo":'•·.t"~: .../, :.._,..:••U· ~SUSITNA .--.:..1..o 320 I J FEET (Approx.Scole) ,<§] ::.,t-_,..... El)RM 123.5 ___SEEPAGE §UPWELLING [!J WATER QUALITY MEASUREMENT SITE*INTRAGRAVEL TEMPERATURE SITE ""'1"~~~ .,-....,.,.·,\"h'..l"'·~-. ,~" -;;:. " U1 .p" Appendix Figure A-44.Upwelling and bank seepage areas in Moose Slough (RM 123.1R). •I :,.~.~I }~J J I 1 I I 1 ))I 1 "--}J 1 ~l )1 -)} ~SUSITNA ~._..;_...'11 ~.~',i":':'lr.'..:,•-,..:',~I' '''';~4.••~,.t'.'·· .....-:..';,. R I VE R _________ o 320 I I FEET (Apprax.Scale I ~'.\/J...~'..,....,.... ..'~" ):;> I 01 01 ':'••),),1'#"¥;"h'",1 it 7o--;ro;.-'o;....,...."t:•.::':~..~. '•.'f',..-,',w ,w.-'F7<-~""i'#"I'··.··C•..,.,',#-0, SALMON SPAWNING AREAS ~CHUM.1983 ~CHUM,1984 CHUM,1981 6 1982.PRESENT,EXACT PINK,1982 11 1984'LOCATION UNKNOWN EBRM 123.5 Appendix Figure A-45.Chum salmon spawning areas in Moose Slough (RM 123.1R). ~SUSITNA ,..........:.•.'....!.IO.t..:.:.".:'-Q ...' RIVER ~ o 320 !I FEET (Approll.Scale) »P .....~ ~ (DRM 123.5 ...Ip·~··· ",r:;/P'A~~' 'y ~r-''' ...wJ~¢f··." I ...~.t.···~ ..U",;. . 0.c:.- ~•."-::J SALMON SPAWNING AREAS ~SOCKEYE,1983 ~SOCKEYE,1984 SOCKEYE,1982 PRESENT,EXACT PINK,1982 a 1984 :LOCATION UNKNOWN ....,."",t....,.·f?',.._;.r4~:.........0fIi,t ..,..........,;,.~ ",,..:::-..r··,:' .,~".. >Irn 0"'1 Appendix Figure A-46.Sockeye salmon spawning areas in Moose Slough (RM 123.1R). ~~}tc I ,i i J 1 ~J t ,•}••-.~ r Passage and silt/sand substrate are the main problems limiting spawning at this site. Slough Al (RM 124.6R) This is a 450 foot long slough at RM 124.6,immediately downstream of Skull Creek,on the east side of the Susitna River.The Alaska Railroad runs parallel to the right bank,crossing Skull Creek near the slough head.The ~erm on the south side of Skull Creek acts as the upper limit of Slough A.There is an intermittent side channel that connects the slough to the mainstem along the left bank at the head.Water from Skull Creek flows intragravelly through the berm into the head of the slough in substantial quantities.Upwelling can be seen in the area of the side channel and is probably the result of mainstem intragravel flow.Upwelling and bank seepage occur along both banks throughout the majority of the slough (Appendix Figure A-47).Upwelling and bank seepage occurring along the left bank is probably mainstem in origin, while that along the right bank is likely due to intragravel groundwater flow and surface runoff. Substrate in the upper half of the slough is rubble/cobble with large gravel while the lower half is large gravel/rubble.The lower backwater area also has a thick layer of silt and sand (Appendix Figure A-47). Salmon utilized all areas of this slough for spawning with a preference for the upper silt free areas (Appendix Figures A-48 and A-49). Limiting factors at this site are minor passage problems at low dis- charges,silt/sand deposits throughout the slough and the small physical size of the site. Slough A (RM 124.8R) Slough A is a 350 feet long upland slough on the east side of the Susitna River,immediately upstream of Skull Creek.The ARR parallel s the right bank of the slough.The first 100 feet consists of a two-foot wide shallow run with large gravel/small gravel substrate covered with approximately eight inches of sand followed by a riffle.Above this riffle there is a 20 x 150 foot pool with deep silt and sand overlying the rubble/cobble substrate.A 100 foot long narrow,shallow run compri ses the upper reach of the slough (Appendi x Fi gure A-50).The entire lower section is a barrier to fish. Upwelling and bank seepage flow out of the berm adjacent to Skull Creek as well as along the ri ght bank of the pool.Thi s seepage is most likely the result of surface runoff and intragravel flow of groundwater. Limited chum salmon spawning was observed only during 1981 (Appendix Figure 51). ·Passage and substrate as well as the physical size of the slough,are the factors limiting spawning. A-57 RM 124,8 $ ·.a ....••.~. SUBSTRATE TYPES ~ S I -SILT.VERY FINE ~ SA-SANDi FINE LG-LARGE GRAVELi 1-3" RU-RUBBLE.3.~" CO-COBBLE.5.\0" I-OVERLYING LAYER RI"Ol ---- ~.I.--'-'..·'0.' SA-SI/LG-RU ~sus/rNA o ~66 I I FEET (Approx,Scole) ):;> I (J1 to Appendix Figure A-47.Substrate composition and upwelling areas in Slough Al (R~1 124.6R). I )'.J )»J l ~I I J !)}I ,I 1 1 I I 1 l -~1 1 ) RM 124,8$ "'I,\J~~' ,"'}J"".,.....r.rf:-:1:I~j!J1.7-••,"~I",'" 'iT f".. .......;i?/}~f"} •i,}i·~):~-.(.f.:···. }jV ,.....' t ,;;..,~7!"-/.;;." .:i:!Jf:i'.::/:':,f.(r:'~"'~· jlY:1r~tfl'~H'~~.~.'..- CHUM SALMON SPAWNING AREAS 1llD1981 111983m1984 R/VER -- ••,:••••_J.!"It ••••:•••t_._.... ~sus/rNA """··~f"=·-""..,<jJ o 66 -I I FEET ..ll\pproll..Scole) )::0 I 111 \.0 Appendix Figure A-48.Chum salmon spawning areas in Slough Al (RM 124.6R). RM 124.8 EB .,.~;lp~5-,~/y,ff!";r!J;r:!'/:7 f:"". :,,:::;/p .•,.p";,>"..(;. ..:':f.;p~",4=(:'" I·:/P~:'?l:-.:f:t ...'·· ....J-..~",/:,.,.~.::.'-,/...~...;.::.;)P~I~,,'IV t·.....,..;;Vi,¥,'£r ;"'..,..;.'2 ;f!1ff:f,~:'~.,...........·t~.Pl'",,~--....-~~ PINK SALMON SPAWNING AREAS 1IDI1984 R/VER -- @ WATER QUALITY MEASUREMENT SITE*INTRAGRAVEL TEMPERATURE SITE 5 .~.....:.!'........'...._,,_.... @* I '~!.':.~!•-~,. ~sus/rNA .'..;.;.:':~."....~.,.:,.,....::•.::,.,,:~:::",...~"".V'",. $ _."-:.\_Wi'JWI.i,:jj',,~\.., l' .,~.......,.:.f":.~J-;....~"::"i...:~.,.:.\r~,•.1.,,..~.,-·-OO~• .~.".....\.·t:0"•••~i ,5 IoU 9 h A I .,.....,,~~:\;':.;--,,~.f.',';··_·.·l ... o!66 (A FEET I pprOll.Scole) :;Do I mo .1 ) Appendix Figure A-49.Pink salmon spawning areas in Slough Al (RM 124.6R). J I t J J 1 ,J J J J )~I 1 ,.J ,}'~~'I 1 l ,JI ~SUSITNA RIVER ---RM 125.0EB ~.'L\;'.~.·."'. '...·-;,·r.':r"......o"i;j'l 'O?'.......tt"fti $ o 66 I I FEET (Approll.Scal,) ~.""i1{·;'·;"·''b·'t'»'«"-ti["...~~•-_.'•"r_"k ,~.~~.._~.,. "·..i'Ul'....-:~ll r f"~~,,'.....,ii ...."Ie-:.,,,~....-.__.~·.T ..... ..........SEEPAGE ~UPWELLING ALASKA RAILROAD SUBSTRATE AREAS 51 ~SILTj VERY FINE SG-SMALL GRAVELj 1/4 -I" LG-LARGE GRAVELjl-3" / •OVERLYING LAYER i·"i....·:..• Creek SI/LG-SG J;=. Ien ~ Appendix Figure A-50.Substrate composition and upwelling areas in Slough A (RM 124.8R). .J """"'SUSI rNA RIVER RM 125.oEB [!]WATER QUALITY MEASUREMENT SITE*INTRAGRAVEL TEMPERATURE SITE ~ o 66 I I FEET (Approll.Seal.) •.A.~.4.t.~••L_" A ~....:u- \_.... II",:,·,··,~:i:'.."<:";'1981~':::""l CHUM SALMON SPAWNING AREAS ALASKA RAILROAD f"i ,%,~...~.:.,i:.....h ~;1'J:.'~.;"!:....,.:~."rf1}'i:\';.~f .-tc-~~'i ..,·I:·;~r" ~,. Riffle :t::o !m N Appendix Figure A-51.Chum salmon spawning areas and sampling locations in Slough A (RM 124.8R). i ],t m .~),I ~J •I ,I 1 )~.J - - - Slough 8A (RM 125.3R) This 2.0 mile long side slough is separated from the mainstem of the Susitna River by a large vegetated gravel bar.Two principal channels, with breaching discharges of 27,400 cubic feet per second (cfs)for the northwest channe 1 and 33,000 cfs for the northeast channel,connect Slough 8A with the Susitna River (Appendix Figure A-52).Local surface runoff and groundwater maintain the base slough flow in an unbreached conditi on. At mainstem discharges between 20,000 and 30,000 cfs,a backwater area extends approximately 1,000 feet into the slough.Above the backwater area is a 100-300 ft riffle that terminates in a large beaver dam.The northwest channel flows into a large pool behind the beaver dam. Channel alignment is straight,with a gentle bend near the head of the slough.Substrate in the lower half of the slough is predominantly large gravel and rubble and cobble and boulder in the upper half of the slough.Depos its of fi ne s il t/sand a re found in the poo 1sand in the backwater area near the mouth (Appendix Figure A-53).A total of eleven passage reaches have been found in this site,the lower four of which can be accessed due to backwater effects at mainstem discharges ranging from 7,700 to 25,000 cfs (Appendix Figure A-54).Breaching occurs before backwater effects can be noti ced on the upper passage reaches. Slough 8A is an important spawning channel for chum and sockeye salmon (Appendix Figures A-55,A-56 and A-57).In 1984 this site accounted for 12.1 and 13.8 percent of the chum and sockeye salmon slough spawning with peak counts of 917 and 128 fish respectively (Barrett et a1.1985). Passage,either depth related or due to beaver dams,appears to be the primary factor limiting spawning in this site.Passage at this site has been more thoroughly discussed in Blakely et a1.1985 and Sautner et a1. 1984. Slough B (RM 126.3R) This is a side slough,approximately 2,000 feet long,located on the east side of the Susitna River at the head of Slough 8A.The slough has a straight channel that is separated from the mainstem by a large vegetated gravel bar.The first third of the slough is a backwater area.The middle of the slough is a large pool,while the upper end °is a divided channel with pool-riffle sequence (Appendix Figure A-58). Substrates are primarily rubble/cobble with occasional patches of large gravel with sand/silt deposits overlying the coarser substrate in the backwater area and first pool (Appendix Figure A-58). In an unbreached condition,water flows intragrave11y through the head from a side channel located upstream.While no upwelling was observed, limited bank seepage from the right bank and heavy bank seepage from the left bank was present.The latter is likely mainstem related.Chum and sockeye salmon spawning is evident in the slough (Appendix Figures A-59 and A-60).A 20 foot long riffle,separating the backwater and pool habitats,is the major passage restriction at lower discharges.The riffle -pool area near the head also exhibits passage problems at low discharges. A-63 )::> i en """ ~ o 500 I IFElT (Appro •.Scolt) .~... RIVeN ,•••.~~••..!••• •~....t iiT"'·~., [i)WATER QUAL-ITY MEASUREMENT SITE III INTRAGRAVEL TEMPERATURE 8IT~. ..~.-",.--.",-..•",•...",.", Appendix Figure A-52.Channel geometry and sampling locations in Slough 8A (RM 1?5.3R). t_J 1 )•I ..c1 J t J !I j J .~.1 J I 1 ~-l ·~-·~1 "-~~-,-1 )::0 I en U1 ....~. <E o 500 I IFEET (Approx.Scole) SUBSTRATE TYPES SI -SIL Tj VERY FINE LG -LARGE GRAVELj 1-3" RU-RUBBLEj 3-5" CO -COBBLE;5 -10" BO-BOULDER;>10" ~:t.••~ .\..t..:-."!".•••. -,..··i NIVeN ~"·i·. ..':.':~...1~j,~••~.. i-."..•....,··.•.•'• Appendix Figure A-53.Substrate composition-in Slough 8A (RM 125.3R). :P I rn 0'1 ~ a 500 I IFEET (Appro •.Scale) Appendix Figure A-54. OIL •....~l!.. NIVeN I' tS'/ -•.,'....,.~.OI;S1~ ..,...,'...... -PR PASSAGE REACH Passage reach locations in Slough 8A (RM 125.3R). t J ••)J t ~I J },i 1 J I )~1 J :I:> I 0'1....... <fJ a 500 I IFEET (Approx.Scale) ,'\i1 _...'._~. .s/0 '".•~..~.; .9~ CHUM SALMON SPAWNING AREAS [llJ)1981 fWMII982lim ~1983 ~1984 h.\..."":1.\......~1'!:...-'.4 ...!...... NIVeN ....,...... ;, cy 1 Appendix Figure A-55.Chum salmon spawning areas in Slough 8A (Rtf'125.3R). J:".> I m 00 ~ o 500 I IFEET (ApprOll.Scole) :...·i- SOCI<EY~SALMON SPAWNING AREAS [lID 1982 ~1983m1984 ••rJ ,._,-'.- NIVEN ,--,'.... .'!.tt:.,: Appendix Figure A-56.Sockeye salmon spawning areas in Slough 8A (RM 125.3R). 1 J B J J .]t J J ,D J J I .~)~"J 1 1 1 ~-J ··~1 ~'"~~l )j .•.~....;~ NiVeN '....'. ;~Oq ..,'.9..., .-..,-., SAL.MON SPAWNING AREAS •PINK.1982 1m PINK.1984 fill]COHO.1982 <J] o 1500 I IFEET (Approll.Scol,) 'J;i.-. :> I en <.D Appendix Figure A-57.Pink and coho salmon spawning areas in Slough 8A (RH 125.3R). ~ ··.~·;;i"l..r.·"....,,,, RM 127.0EB o 130 I 1 FEET (ApI/roll..SCQI,) .-..•..."......:...-{- -'.. #~t·•.•.•-.••11 .·~•..:l.·..'!Ir·.\a.'b sueSTRATE TYPE! .':"SA-SANDi FINE (f) L G •LA RGE GR AV El~i I·3"~~ RU-RUBBLEj3.5 "y CO-COBBLEi 5 -10" / -OVERLYING LAYER ........,,-••0\".O"'-:P!'..........a..,.'".•"'....·....... NIVEN~ ..y~...........~ _!••" - .,.....;.•""l ....\.-._!..._...... ~sus/rNA "'o.ll'!.'•.!L... Siougn 8A N- [!]WATER QUALITY MEASUREMENT SITE*INTRAGRAVEL TEMPERATURE SITE .......-SEEPAGE )::- I......a Appendix Figure A-58.Substrate composition,bank seepage,and sampling locations in Slough B (RM 1~6•3.R)• ))'J I 1 J ~~.1 J ~)J J &J ~,~ )1 ---1 --]-1 1 1 1 ~ ·'.Pn:;"·"'\' RM 127.0EB o 130 I I FEET (Approx.Scale) ............~)-.V"...:~ <fJ ·.·--"0.·.,1 ....; '-7 ..*n '.1 ;\".","'(0.')'., sUs/rNA~ ....J ···_!,.·.·.w:o.a.-.•: Slough 8A ..4' ·_··...l ...• CHUM SALMON SPAWNING AREAS fWl;j 1982 III 1983 ~1984 ~",,4 ...~,_. ):- I --.J t-' Appendix Figure A-59.Chum salmon spawning areas in Slough B (RM 126.3R). ~ RM 127.0EB o 130 I I FEET (Approll.Scole) lE ·•....'··.i. ''U(f''1I~'''''~''''''- •,':'••6.·........\'..f;.·.r.t. ..~~...";. N/VEN~ ·e-'I sUs/rNA ~.,•••.•••.)I":"";",, •.•u-_,",.•O\..'. ....----.J Slough 8A r!¥ SALMON SPAWNING AREAS IIID SOCKEYE,1982 ~SOCKEYE,1984 ~PINK,1982 •~-'f_.,..~,!.'j ..!l.... ::> I '! N Appendix Figure A-60.Sockeye and pink salmon spawning areas in Slough B (RM 126.3R). J !I ~)I ~~.1 J J J J J !J ,~J J ~ - .- Factors limiting spawning at this site are passage,substrate,and lack of upwell ing. Slough 9 (RM 128.3R) Slough 9 is a 1.2 mile long side slough on the east side of the Susitna River.Base slough flow is maintained by upwelling and two small creeks that enter the slough at approximately 0.2 and 0.75 miles upstream of the mouth (Appendix Figure A-61).When breaching occurs at mainstem discharges exceeding 16,000 cfs,slough flows become turbid and rapidly increase from less than 10 cfs to approximately 100 cfs or higher. The slough channel has several gentle bends that occur throughout the site.A right angle bend occurs near the second creek where the slough turns from east to south after coming in contact with rip-rap along the Alaska Railroad which parallels the right bank of the slough.Substrate composition in the lower two-thirds of the slough is predominantly gravel and rubble covered by a four to five-inch thick layer of sand. Substrate in the upper one thi rd of the slough is exposed cobble and boulder in riffles with sand deposits in pool areas (Appendix Figure A-62). Passage can be a problem,with five passage reaches being described by Blakely et al.1985 and Sautner et al.1984 (Appendix Figure A-61). Slough 9 is an important chum salmon spawning site,with extensive spawning activity occurring throughout the slough (Appendix Figures A-63 and A-64).In 1984 this·site had a peak count of 350 chum salmon accounting for 4.6 percent of the total slough spawning escapement (Barrett et a1.1985). Factors influencing spawning at this site are passage and substrate. Dewatering of the upper half of the slough during unbreached conditions also affects the extent of spawning. Slough 9B (RM 129.2R) Slough 9B is located inside Slough 9,about 1,000 feet downstream of the head along the right bank.The overall length of this upland slough is 1,750 feet.The channel forks 1,250 feet from the mouth,formi ng two narrow riffle areas.Downstream of this point,the slough is a long 'Pool,3 to 4 feet deep.Thickly vegetated banks occur throughout the slough.The slough has little flow due to the extensive beaver activity.As a result,a thick silt layer with decaying organic matter overlies large gravel/rubble substrate.Strong upwelling occurs throughout the slough,especially along the left bank (Appendix Figure A-65).Salmon selected these upwelling areas for spawning,digging through 18 inches or more of silt to reach the useable substrate. Access to this site is provided through Slough 9,which can bea problem when passage in Slough 9 is restricted.Two large beaver dams,at the mouth and 1,250 feet upstream of the mouth,were built in late 1982, resulting in completely blocking passage to this slough for spawning salmon since the fall of that year.Numerous smaller dams occur in the A-73 -PR PASSAGE REACH ~ o 400 I I FEET (Approll.Seol.) SEEPAGE UPWELLING ·~"<·-"'1··;"'·:';~·~j~..!'.\'.~i'~J!?i'!~:J...".•<J..••'......~ ---~ f?,VEf?--Q)RM 129.0 ):::0 I....... -I=> Appendix Figure A-61.Upwelling areas and passage reaches in Slough 9 (RM 128~3R). s j J I J .J •J J J }1 J )i D )J J }1 ----1 ~--1 '---1 ~'-1 ;)J ] 98 ~_.h•••• •:......;:..\:......·:l.....·j...:..;...:ft:U-~.., o 400 I I fEET (Approx.Scole) SUBSTRATE TYPES 5 I-SILTj VERY FINE SA·SANDi FINE LG·LARGE GRAVELj 1-3" RU -RUBBLEj :3 -5" CO-COBBLE;5-10" BO-BOULDER;:>10 11 /·OVERLYING LAYER ~ ~,,,ER --EBRM 129.0 ~S\-,.......,1.~:"':;~'~:;;"'C;,d ,,-.-.'~'~';..:,i."'J'.~ ;po I --.J U1 Appendix Figure A-62.Substrate composition in Slough 9 (RM 128.3R). 9B.;"'._1"._"· ~ ::":';~.A9i ...~~.""I.'h- o 400 I I FEET (Approll.Scol,) CHUM SALMON SPAWNING AREAS .1981 ~1982m1983 lIlD 1984 RIVeR ~$RM 129.0 )::> I ......... en Appendix Figure A-63.Chum salmon spawning areas in Slough 9 (RM 128.3R). )J .J J )~I J ,J 1 J )J t I !J J ]-~~-j 1 -1 l J )j m WATER QUALITY MEASUREMENT SITE*INTRAGRAVEL TEMPERATURE SITE )::> I -.....I -.....I 0*I \'•••,.,.'•••.\-;r,,:... ~ '" .",,(?Ar:....¥:...,.'..~·~-\··;<;.. Smil,Cr,1k EBRM 129.0 RiVER --- SALMON SPAWNING AREAS ~SOCKEYE,1982 mm PINK 1982mm• ~ o 400 I I FEET (Approx.Scale) Appendix Figure A-64.Sockeye and pink salmon spawning areas in Slough 9 (RM 128.3R). ::Do I -....J ;~ .~.7";(\~ ,.~\() ~if,.J~~J.i:Ci:~·· • -•.Ll'~,.: SUBSTRATE TYPES S 1-SIL Ti VERY FINE LG·LARGE GRAVELi 1·3" .I·OVERLYING LAYER ~UPWELLING @ WATER QUALITY MEASUREMENT SITE*INTRAGRAVEL TEMPERATURE SITE <J] o 200 I I FEET (Approx.Scal.) Appendix Figure A-65.Substrate composition and upwelling areas in Slough 98 (RM 129.2R). ~J J .J _J J )J J )J I ..~~),I )) r I I channel s upstream of the second major dam.In 1984,ADF&G personnel created temporary openings in both dams to provide passage into the slough.Chum and sockeye salmon moved into the slough and spawned duri ng a peri od of hi gh water whi ch provi ded passage through Slough 9 (Appendix Figures A-66 and A-67).Numerous fry (up to 6 inches in length)were observed in the slough prior to opening the dam at the mouth.They immediately migrated downstream when the dam at the mouth of the slough was opened. Factors limiting salmon spawning in this slough are passage (through Slough 9 and into Slough 9B)and substrate.Both passage into Slough 9B and the substrate problems can be directly related to the extensive beaver activity throughout the site. Slough 9A (RM 133.2R) This is approximately an 0.6 mile long by 50 feet wide,side slough on the east bank of the Susitna River,separated from the mainstem by a long vegetated island.Breaching occurs at mainstem discharges greater than 12,000 cfs,creating one long run.Below 12,000 cfs,the wetted area develops into a series of pools and riffles.Ten passage reaches occur at various discharge levels and are discussed at length in Blakely et a1.1985 and Sautner et a1.1984 (Appendix Figure A-68). There appears to be good bank seepage and upwelling along the entire length of the slough (Appendix Figure A-6B).Mainstem influence is probably the driving force along the left bank,while runoff from the mountains influences the right bank.Substrate composition in the slough is predominately rubble/cobble.Areas of large gravel exist in pool areas throughout the slough while cobble/boulder predominates in the riffle habitats (Appendix Figure A-69). Chum and sockeye salmon spawn in Slough 9A (Appendix Figure A-70 and 71) with a peak 1984 chum salmon count of 303 fish or 4.6 percent of the total slough escapement.A channel on the right bank at the head is also heavily utilized for spawning.This channel has good substrate throughout most of its 1ength with upwell ing and bank seepage.Fry were observed in pools throughout the slough. Spawning habitat improvements include removing passage barriers and minor substrate replacement. Slough 10 (RM 133.8L) This site is an upland slough on the west side of the Susitna River consisting of two channels that diverge 250 feet upstream of the mouth. The left channel extends approximately 3,000 feet in a northerly direction ending in a series of beaver dams and ponds,while the right channel extends 1,500 feet in an easterly direction.The area below the junction of the two channels is primarily a backwater.The left channel consists of a long run with an occasional riffle and pool while the right channel is a run/riffle area (Appendix Figure A-72).Substrate A-79 )::0 I 0:>a CHUM SALMON SPAWNING AREAS lIllII981 ~1982 ~1984 ~.q."",~.~ .(),.-\....c; .' &~~~~;';"·i··_'l~~. "...~,~ ~ o 250 I IFEET (Appro •.Scale) Appendix Figure A-66.Chum salmon spawning areas in Slough 9B (RH 129.2R). ]J ~,J g )J 1 I I ~•.~j ~!)j )1 j I .---1 1 ~-]--I .._--]-J 1 ~--,I I I J J I :;po I CO....... SOCKEYE SALMON SPAWNING AREAS ~1981urn1984 .;,;,q .'".~..) ..,.\() "'J $7;;;;/}""91;/' " ......-::"lS~'.~.~·:.,:~.. <JJ o 250 !I FEET (Approx.Scole ) Appendix Figure A-67.Sockeye salmon spawning areas in Slough 9B (RM 1?9.~R). '.~..•""". ·:·:~~·~~fi;;.:;0;~i O~.:f:'t:;~••~• ..~.~~;~: oo / .:j;tt1[i;(g¥.;;·[r;:\t':w~; ~WATER QUALITY MEASUREMENT SITE •INTRAGRAVEL TEMPERATURE SITE RIVER .-:J ::·~!}lf/~~Ef.ff·!}/·:, ~SEEPAGE ~UPWELLING \"1" ----PR PASSAGE REACH SLlS l1NA / o <&JI275'A"," FEET I ry (Appro •.Scol.) ):> i 00 N Appendix Figure A-68.Passage reaches and upwelling areas in Slough 9A (RM 133.2R). .~J I J I J J ~.___J J ~})])) 1 ))1 1 -}~.-J ,---]1 ·::~;·~;·r~;;ii~~l;~j .•1'.l ....\,•.I.'.~..(:'!;~:- "~~t:~:.: LG-RU-SI •_.."~..T ...·.......~':f"iCt·iIJ~·L;et:.,.· ·{~}~i«;I~i!)Jfi;~;;W;~ .'!....... ,,:·!·/}'~'~~}<er;~}::':. RIVER SUBSTRATE TYPES LG*LARGE GRAVEL;1_3" RU-RUBBLE;3_5" CO-COBBLE,5_10" BO-BOULDER;>10" ...-.-..,..... slJSrfNA / o <§},2715 ,A.. FEET I ..Y (Approll.Scale) EB RM »> Ico W Appendix Figure A-69.Substrate composition in Slough 9A (RM 133.2R). ._-'.·.·t·,A •.. ;<~~\\t~~; "o ·<Sf~lti~f.i~(r;i;~i;it~·<)l~·//}f:·;;'U.2?:· RIVER '"~ \JghS\~~4 .••_lOA' l"l'i__• CHUM SALMON SPAWNING AREAS 1IIIl.198 I .1982 ~1983 ~1984 SlJSlfNA / ~"r"<iJFEETry (Approl.Scol,) )::> n CO.p. Appendix Figure A-70.Chum salmon spawning areas in Slough 9A (RM 133.2R). I ~),.~)i .J ,J J ),~)~~.~ l~Cl 1 J ])J ~C-J 1 I ] ';'fr~;~liJ~ oo /t\~~[lt~;!t(;~~}\~:i!',,:·~)/~·;:·?}M1:a?:·:· RIVER !,fq~'1982 ~1983 1981.PRESENT.EXACT LOCATION UNKNOWN SOCKEYE SALMON SPAWNING AREAS SUSlfNA (J] / o 215 I I FEET I Approx.Scale) .::"...~.~":.::"i4;...j...j'~~'''~~ )::> Ico <.11 Appendix Figure A-71.Sockeye salmon spawning areas in Slough 9A (RH 133.2R). ~ o SOO I I FEET (Approll.Scale)~\::!~"·;\I.."'c.\......,.f.""", ~:;4:-.':';~~......;'r.'-\.~.~~.r;[ [!)WATER QUALITY MEASUREMENT SITE •INTRAGRAVEL TEMPERATURE SITE ~SUBSTRATE SAMPLE SITE mJ DATAPOD SITE :;::;. I 0:> 0'> Appendix Figure A-72.Channel geometry and sampling locations in Slough 10 (RM 133.8L). •I J i J 5 J S J ,i 1 ~,J .~~,J ....., through most of the slough,except the right fork and upper reaches of the left fork,is composed of a deep silt layer over cobble/boulder. The right channel is predominately cobble/boulder covered by thin sand deposits.The upper reaches of the left channel is primarily rubble/cobble substrate with very little sand or silt (Appendix Figure A-73).The slough is maintained by water draining from the bog and beaver ponds at the head as well as the very extensive upwelling and bank seepage occurring throughout the slough (Appendix Figure A-74). Chum salmon have been observed spawning in this slough since 1982 (Appendix Figure A-75). It appears that substrate is the primary factor limiting spawning. Slough 11 (RM 135.3R) Slough 11·is an important spawning site for chum and sockeye salmon (Appendix Figures A-77 and A-78)as well as pink salmon (Appendix Figure A-79).It is responsible for 21.3 percent of the chum salmon and 61.0 percent of the sockeye salmon total slough distribution (Barrett et al. 1985).It consists of a 0.9 mile side slough beginning at RM 135.3 with access via Lower Side Channel 11.The head is situated in the middle of Upper Side Channel 11.The breaching discharge of the head is estimated at 42,000 cfs.Base slough flow is maintained by extensive upwelling and bank seepage (Appendix Figure A-80).The wetted area consists of a series of pools and riffles.Seven passage reaches have been defined by Blakely et al.1985 and Sautner et al.1984 (Appendix Figure A-80).The lower two are read"ily overcome by backwater effects at mai nstem di s- charges of 19,400 cfs and greater. There is a large degree of variability in the substrate in this slough (Appendix Figure A-81).The riffles and the head are predominately rubble/cobble/boulder.The pools,which are the major spawning areas, are large gravel/rubble covered by a thin layer of silt.The backwater area consists of thick silt/sand deposits overlying cobble/boulder substrate • Fry have been observed throughput the slough.Passage is a primary factor inhibiting spawning in this site.Minor substrate cleaning and replacement may also be necessary to improve spawning conditions. Slough 12 (RM 135.4R) Slough 12 is a 0.3 mile long former side slough that has had its head filled in and overgrown with vegetation.This upland slough originating in a bog between Sloughs 11 and 13 is now primarily beaver habitat.It empties into the side channel above the mouth of Slough 11 at RM 135.4. A small creek drains into the right side of the slough approximately 600 feet upstream of the mouth.Below the creek the wetted area consists of a backwater area and short riffle followed by a long deep pool.Beaver activity is prevalent throughout the slough.A vegetated sand bar at A-87 >- Icoco '~-"oi\.CO-RU-BO SUBSTRATE TYPES S I -SILT j VERY FINE SA-SANDi FINE RU·RUBBLEj 3_5" CO-COBBLEi 5-10" BO·BOULDER.>10" /.OVERLYING LAYER '.~.....',.". <E o 500 I I FEET (Approll.Scolt) Appendix Figure A-73.Substrate composition in Slough 10 (RM 133.8L). ",l I J ,I ~~I ~.~t ~t 1 1 I 1 J -I }1 --:1 ~..._---~}"-~--l } ;p- I ro 1.0 Riffle/Mud Bea",r Dam --.-SEEPAGE ~UPWELLING 0_,-.:..~",.':'l...,\,_\..~_._.... .~.\;..\~~~....&.- <§} o liOO I I FEET (Approlt.Scale) ./ Appendix Figure A-74.Upwelling and bank seepage in Slough 10 (RM 133.8L). "1> ".<.0o CHUM SALMON SPAWNING AREAS II 1982 ~1983 ~1984 4·..·!'••a Appendix Figure A-75.Chum salmon spawning areas in Slough 10 (RM 133.8L). ... <JJ o ~OO I I FEET (Approx.Scale) I j l 1 }J t I I t ..~.~I J ]»I 1 )---,\I J ·-1, );:> I 1.0 t--' •STANDPIPE SITE a NUMBER '~\, Appendix Figure A-76.Standpipe locations in Slough 10 (RM 133.8L). <JJ o 500 I I FEET (ApprOll.Scale) );:> I l.O N CHUM SALMON SPAWNING AREAS 1IllIl198 I ID.111982 ~1983 ~1984 ~ UppfJr Side Channel /I ~ o 300 I I FEET (Approx.Scole I Appendix Figure A-77.Chum salmon spawning areas in Slough 11 (R~1 135.3R). J 1 j J J J !,B l .~.J ).~~~I ~I ) ··--1 "'-1 --'-')))}))-J j ~ I ~ W SOCKEYE SALMON SPAWNING AREAS nm 1981 E 1982 ~1983 ~1984 ~ Upper SidfJ Channel /I ~ o 300 I I FEET (Approx.Scale) Appendix Figure A-lB.Sockeye salmon spawning areas in Slough 11 (RM 135.3R). ~ Upper Side Channel /I ~ PINK SALMON SPAWNING AREAS 81982 fllVf~ fNASUSIEDRM ;Do I 1.0+:> [i)WATER QUALITY MEASUREMENT SITE*INTRAGRAVEL TEMPERATURE SITE ?3YO FEET (Approll.Scole) Appendix Figure A-79.Pink salmon spawning areas in Slough 11 (RM 135.3R'. J )1 J ).~1 t J l J ,,J J J ) )::> I ...0 U1 ~-~-l ,-l ~ -PR PASSAGE REACH ~SEEPAGE ~UPWELLING ---'"--1 1 Uppsr Side Channel" '...'•.,~,.,-,'i'·;..:~~,........ ,"........-. .",'..' ~ ?3YO FEET (Approx.Scale) 1 Appendix Figure A-80.Passage reach locations and upwelling areas in Slough 11 (RM 135.3R). ~ o 300 I I FEET (Approx.Scale I Upper Side Channel /I ,,/' SUBSTRATE TYPES 51 -SILTj VERY FINE SA-SANDi FINE LG-LARGE GRAVELj 1-3" RU-RUBBLE i 3 -5" CO-COBBLEi 5_10" BO-BOULDER;>10" ·~I"f~ If NA SLJ S El)RM ::t:>, <.0m Appendix Figure A-81.Substrate composition in Slough 11 (RM 135.3R). 1 1 11 ,),,]..J.)·~I ,I I J I ~J ..- - - the mouth severely limits passage to this site except at high mainstem discharges (Appendix Figure A-82). Deep silt substrates are found throughout the channel except in the riffle area where rubble/cobble predominate.(Appendix Figure A-83). Littoral and riparian vegetation flourish in and along the pool ..No spawning has ever been recorded nor was upwell i ng or bank seepage evident in this site.During winter it was frozen over,indicating an absence of upwelling. Because of numerous problems associated with this site (passage, substrate,flow,upwelling,beaver activity),modifications to this site to improve spawning habitat would be extensive. Slough 13 (RM 135.5R) Slough 13 is a 0.5 mile long side slough on the east side of the Susitna River located immediately upstream of Slough 12 at RM 135.4.Two low lying heads join the slough to the mainstem with breaching appearing to be a frequent occurrence.In an unbreached condition,the slough is maintained by upwelling,bank seepage and intragravel flow from the mainstem (Appendix Figure A-82).Substrates in this slough are primarily rubble/large gravel in most areas.Silt and sand deposits accumulate in pools throughout the slough,reaching depths of one foot or greater (Appendix Figure A-83).For the most part,the wetted a.rea is a riffle/run/pool system.Passage problems exist in the riffles during unbreached conditions when the majority of the site dewaters. Chum salmon have been observed spawning in the upper reaches of this slough (Appendix Figure A-84).Historically,this is not an important slough spawning area.A limited number of fry were observed in a small tributary along the right bank near the head.Extensive work would be needed to improve and maintain the spawning habitat in this slough.It is not considered a prime mitigation candidate. Upper Side Channel 11 (RM 136.0R) Upper Side Channel 11 (RM 136.0R),located on the east bank of the Susitna River,is a single straight channel approximately 0.4 miles in length that is separated from the mainstem by a well vegetated island (Appendix Fi gure A-85).Approx imate ly 1,400 feet upstream from the mouth,Upper Side Channel 11 is connected with the head of Slough 11 along the right bank.Channel morphology is rectangular,sloping gently on both sides to vegetated banks.Breaching occurs at mainstem discharges greater than 16,000 cubic feet per second.In an unbreached condition,base flow in the side channel is maintained by upwelling and bank seepage along both banks,primarily in the lower third of the slough (Appendix Figure A-86).The side channel is a backwater followed by riffle pool sequence. The backwater area in Upper Side Channel 11 extends approximately 450 to 500 feet into the side channel with corresponding mainstem discharges of 11,400 to 31,700 cfs.Above the backwater area,Upper Side Channel 11 consists of a series of long riffles and pools.Silt and sand deposits A-97 [!J WATER QUALITY MEASUREMENT SITE*INTRAGRAVEL TEMPERATURE SITE 1\... :~...,..'., 'I t"..~;' [!}*4 ~ o 600 I I .FEET (Approll.Scale) ~ RIVER ......., ,.:,-:••.;t"".~"r..•.':0'••••• ;po I <.0co Tributary Appendix Figure A-82.Upwellng areas and sampling sites in Slough 12 (RM 135.4R)and Slough 13 (RM 135.5R). J ~I -~I J 1 ~I J ),.~J J ~,I J -.• ))t i ,1• ~ SI/RU-CO o 600 I I FEET (Approx.Scale) SUBSTRATE TYPES 51 -SILT;VERY FINE SA·SAND;FINE LG·LARGE GRAVEL;1-3" RU-RUBBLE,3 -5" CO-COBBLE;/)-10" /-OVERLYING LAYER ~ fl1vE:R ,r;: t~: ......,.,,..t .....t'.•....f;.···~...:..;f:·' -.-·~·;/t·~';t.';W:\·)···:··· Trlbutory suslrNA ~(l)RM 135.5 )::> I <.0 <.0 Appendix Figure A-83.Substrate composition in Slough 12 (RM 135.4R)and Slough 13 (RM 135.5R). ~ a 600 !1 FEET (Approlt.Scale) CHUM SALMON SPAWNING AREAS mn 1981 ~1983 ~1984 ~ fl lVER ·\......_.':'<".'A'~.•.••,..,.,:..:M''''·~·:'·~·.... Tributary ____SU 5 ,r NIl ~€aRM :P I I-'aa Appendix Figure A-84.Chum salmon spawning areas in Slough 13 (RM 135.5R). ))I J )I J j J •~j ~J )J ).~) ---,-~--,,,}}-)J )-)l 'I, ALASKA RAILROAD \ ~ (I 400 I I FEET, (A pproJ\.Scal.) ,',-:;'."".;~I.~"" ~ ..-p .........~ ~..-p U'c:;... .U' ........,A ~ ""9 ~ t£)RM f36.0 (!]WATER QUALITY MEASUREMENT SITE*INTRAGRAVEL TEMPERATURE SITE ~SUBSTRATE SAMPLE SITE [Q]DATAPOD SITE ".~_:.:....,; lJ 9 h..,..:....r".' 5 10 ,.0'· ,.':,:' ;:t;> I I--' o I--' Appendix Figure A-85.Channel geometry and sampling sites in Upper Side Channel 11 (RM 136.0R). ;p- i t-> o N ED RM 136.0 -PR PASSAGE ~SEEPAGE ~UPWELLING o 400 I I FEET (ApprOIl.Scol.) ~ Appendix Figure A-86.Passage reaches and upwelling areas in Upper Side Channel 11 (RM 136.0R). J t -,j !,))J I J J a ]ci .1 1 •••) _. - occur in the backwater and pool areas with cobble and boulder substrate predominating in the riffle areas (Appendix Figure A-87).The gradient of Upper Side Channel 11 is approximately 23.6 ft/mi with the corresponding mainstem gradient of 16 ft/mi. Two passage reaches have been identified in this site (Appendix Figure A-86).Except for the one occurring in the backwater (PRI),breaching discharges are required for successful passage {Blakely et a1.1985 and Sautner et a1.1984}.Chum salmon spawning occurs primarily in the backwater area.When passage is possible,spawning will also occur in two pools near the middle of the side channel (Appendix Figure A-88). Factors limiting spawning in this site are substrate and passage. Slough 14 (RM 136.0L) This upland slough is an expansive swampy area consisting of a series of beaver dams and ponds located directly across the river from the mouth of Upper Side Channel 11 {Appendix Figure A-89}.The first dam is 50 feet from the mouth.Below this is a fairly straight run with rubble/cobble substrate covered by silt.The channel is narrow, approximately 15 feet wide,and heavily vegetated on both banks. Several large beaver ponds,about six to eight feet deep,exist throughout thi s slough.The substrate in the ponds is covered by a thick layer of decaying organic material and silt. The beaver dams act as complete barriers to fish passage.Although the area below the first dam may be suitable for limited spawning,no spawnoing activity has been recorded.No fry were observed in the slough.Little flow is apparent in the slough.The water is stained due to decaying organic matter. Passage,substrate and possibly low dissolved oxygen during the winter are the limiting factors to spawning in this site. Slough 15 (RM 137.2L) Slough 15 is a winding side slough,approximately one half mile long, with high,stable,vegetated banks located on the west side of the Susitna River,approximately one half mile upstream of the ARRGo1d Creek bridge.A beaver dam 300 feet upstream of the mouth as well as one at the head,"has made th iss1ough along beaver pond totally inaccessible to fish (Appendix Figure A-90). Large gravel/rubble substrates predominate in the lower half of the slough with cobble/boulder predominating in the upper half.The majority of the slough is covered with silt/sand substrate varying in depth from 2 to 18 inches (Appendix Figure A-91). The area below the first beaver dam is either a backwater or riffle,. depending on the mainstem discharge.The head is a cobble/boulder riffle dropping sharply from the beaver dam to the mouth of Slough 16. Due to the beaver darns altering the water surface elevation in the slough,water runs out both the mouth and the head.Limited upwelling A-I03 '/, :P- I I-'a -Po $RM 136.0 SUBSTRATE TYPES SI ~SILT,VERY FINE LG-LARGE GRAVEL;I ~3" RU-RUB BL E;3·5 "~II CO-COBBLE-5·10."B0 - B0 UL 0 E R i :>10 / -OVERLYING LAYER I ,.,;'I ..-,.~_.r",Ll g,~.,..,.y 51?~.:' ,";":.' ~ U'c.- U'\ ......,....>0.. "Z..- "'9' .-p ......L.- ~ 'P ~ o 400 I I HET (Approx,Scole) )A"~l~ 'ALASKA RAILROAD \ Appendix Figure A-87.Substrate composition of Upper Side Channel 11 (Rt1 136.0R). J t )J J ,))J J J .1 )'~1 I )~ 1 1 1 )J ))}1 1 J )1 ] .>~>':~ FEET (fI pprox,Scal.) 400 I ~ (I L ~ ~....... L- <" ""f) ·1.-.- U"c::::.. U" .......--" ..z., -V ~ ffiRM 136.0 CHUM SALMON SPAWNING AREAS ~1981nm1982 01983:::~:.::;.~::' ~1984 )::- I I-' o CJl Appendix Figure A-RR.Chum salmon spawning areas in Upper Side Channel 11 (RM 136.0R). SUBSTRATE TYPES SI -SILT.VERY FINE RU -RUBBLE.3 -5" CO-COBBLE;5~10" / -OVERLYING LAYER [!]WATER QUALITY MEASUREMENT SITE*INTRAGRAVEL TEMPERATURE SITE a 320 I I FEET (Approx.Scal.) $ ED RM 136.0 :P I ~o Cl"l ~--sus/rNA RIVER -__ Appendix Figure A-R9.Channel geometry,substrate composition,and sampling sites in Slough 14 (RM 136.0L'. ~)J 1 )-'J ~I ,i )J 1 J I ):> B I--'a "'-I o 500 I I FEET (Approx.Scale) <] -1 '\.:o~"....!.~~~_.._:•..:....::..:-;,..... 0_•.••...".........,,'... -.-SEEPAGE ~UPWELLING rn WATER QUAliTY MEASUREMENT SITE •INTRAGRAVEl TEMPERATURE SITE ..~/.•;\i·.......~~.......\..~.J'"•....~~...~.--!:•••,.._•.•. J ) RM 137.5E9 ~sus/rNA R/VER Appendix Figure A-90.Channel geometry,sampling site,and upwelling areas in Slough 15 (RM 137.2Ll. ". I I-'o CO o ~OO,I FEET (Appro•.Scol.) <J] '..............'~'"---)£:,.,-•.,)"",""''''+')'',;"::1 -I.·••·~r.-.:.J.\.. RM 137.5$ SUBSTRATE TYPES S I •SIL Tj VERY FINE LG-LARGE GRAVELj 1.3" RU·RUBBLE;3-5" CO-COBBLE;5-10" / -OVERLYING LAYER y---SUSlrNA RIVER Appendix Figure A-91.Substrate composition in Slough 15 (RM 137.2L). ,),j ),)!)))J )~~)!J and bank seepage is present,primarily along the left bank near mid slough (Appendix Figure A-90).The water is stained brown indicating a marsh or bog origin. Limited spawning by chum and pink salmon occurred in the mouth area during 1984 (Appendix Figure A-92).The mouth area is consistently used as a mi 11 i ng area by chum,pi nk,sockeye,and coho salmon.No fry were seen throughout the slough. Major factors 1 imiting spawning are passage (primarily due to beaver activity),substrate,and possibly low flows. Slough 16 (RM 137.7L) Immediately upstream of the head of Slough 15 is Slough 16 at RM 137.7. This is a 1,100 foot long,bow shaped side slough on the west bank of the Susitna River.Channel morphology is rectangular with gently sloping banks on both sides.Substrate in this site is a uniform mixture of large gravel,rubble and sand (Appendix Figure A-93).The head of this sloUgh is adjacent to the mouth of Slough 16B and portions of the water running out of the mouth of Slough 16B enters Slough 16. No upwelling or bank seepage has been recorded at this site.Limited chum sal mon spawni ng has occurred with a peak count of 15 chum salmon recorded by ADF&G personnel in 1984,accounting for 0.2 percent of the total slough spawning (Appendix Figure A-94). Passage and to some extent substrate are limiting to spawning in this site. Slough 16B (RM 137.9L) This is a 2,000 foot long bow shaped side slough,located on the west bank of the Susitna River adjacent to the head of Slough 16.The 0.4 mile channel is separated from the mainstem by a large vegetated island. Breaching discharge is 23,000 cfs.Below the breaching discharge,the slough becomes a series of shallow pools separated by long riffles with the upper third of th.e slough dewatering and becoming a cobble/boulder berm.Rubble and large gravel predominate in the wetted areas,while cobble/rubble can be found along the banks and occasionally in the riffles (Appendix Figure A-93).These gravels and cobbles are relatively free of any silt or sand deposits except in a small pool at the mouth. No evidence of upwelling or bank seepage was observed in Slough 16B. One chum salmon redd,the first observed spawning in this site since 1982,was observed in a pool at the mouth of Slough 16B in 1984 (Appendix Figure A-94). Slough 16B has good substrate throughout the site.The problem limiting spawning appears to be water quantity in an unbreached state,which in turn affects passage into and through the site.Due to lack of water and no apparent upwelling the site most likely freezes during the wi nter. A-109 );> I I-' I-'a o 500 I 1 FEET (Approll.Seol.) <J] •.h.i:(:~•...::...\:s.,••.\.c._('.t"••••l·...__ "l,:!It".'\,'0-.\·.•.:1-.L·.1,....~\·~\_~",,:"••~',~~.:..~.01'.:0:'0":-t",to ._.,.'~•• SALMON SPAWNING AREAS ~CHUM,1984runPINK.1984 RM 131.5E9 ~SUSITNA RIVER Appendix Figure A-92.Chum and pink salmon spawning areas in Slough 15 (RM 137.2L). })~t )J ,,I ,J I J J ~.~D ~J ]c"".cC!l ..'Ii ~11 11 J J :-)j )1 ) I .J o 500 I I FEET (Appro •.Scale) <JJ SUBSTRATE TYPES SA·SANDi FINE LG -LARGE GRAVELi 1_3" RU-RUBBLEj 3_5" CO-COBBLEi5-IO" BO-BOULDERj >10" .~'/ mRM 138.0 ~/J/c~ ~ St./S/T,Ay4 .-J"- > I I-' I-' I-' Appendix Figure A-93.Substrate composition of Slough 16 (RM 137.7L)and Slough 16B (RM 137.9L). ffiRM 138.0 /;J /J;'C /i' ~ CHUM SALMON SPAWNING AREAS ~1981 mIl 1984 S{/S/rIV4 ill WATER QUALITY MEASUREMENT SITE •INTRAGRAVEL TEMPERATURE SITE S IoU 9 h .1.68 "«';'."'''';-:~..,:."••,'.....-.,••..•".:'-":''1.;......::.,.. ..~.....'(!j*3 ~ ~-.-J <fJ o ~OO I I FEET (Approl.Scole) ~ I ~... I--' N Appendix Figure A-94.Chum salmon spawning areas and sampling locations in Slough 16 (RM 137.7L) and Slough 16B (RM 137.9L). J .~)1 -J J )J I )J J ).J .):,I t ~ "r" i ! I.,, "1"" i i Slough 17 (RM 138.9L) This is a reasonably productive upland slough located on the west bank of the Susitna River.This is a former side slough/side channel that has had the head gradually fill in and revegetate so that it no longer breaches.Beavers have claimed the majority of the slough for their use with a series of three beaver dams,beginning 800 feet upstream from the mouth,which are total·barriers to fish passage.A long forked pond with silt substrate is located upstream of the dams (Appendix Figure A-95).The major area of interest however,is below the dams.This is a 600-700 foot run over primarily large gravel/rubble substrate with si lt and sand accumu1 ati ng in most areas due to frequent backwater affects.The right bank is a gently sloping mud bank with sparse vegetation.The left side is a cut bank with overhanging vegetation. Upwelling and bank seepage are extensive in this reach,especially along the left bank (Appendix Figure A-96).Sockeye and chum salmon spawn in this slough including at least one instance of spawning beyorid the first two dams (Appendix Figures A-97 and A-98).Surveys conducted in 1984, showed peak counts of 66 chum salmon and 16 sockeye salmon for 0.9 and 1.7 percent of the total slough distribution respectively. This site exhibits promise for being more productive but only through extensive habitat manipulation including beaver control,removal of beaver dams,substrate cleaning or replacement,and possible flow augmentation to keep substrate clean and provide passage. Slough 18 (RM 139.1L) This small upland slough drains a bog area adjacent to Slough 17.The total length is approximately 800 feet,which consists of a narrow channel with two small adjacent pools (Appendix Figure A-99).The banks are heavily vegetated and littoral vegetation persists all along the slough.Substrate is thick silt over an unknown base.No upwelling or bank seepage was observed. The first observed spawning,located in the two pools in the middle of the slough,was in 1984.(Appendix Figure A-99).A peak count of eleven chum salmon were observed in these areas.Limited numbers of fry were observed throughout the two pools.There is evidence of beaver activity in the channel upstream of the two pools. Limitations to spawning in this site are passage into and within the slough,substrate and water flow. Slough 19 (RM 139.8R) This is a 1,000 foot long upland slough located on the east bank of the Susitna River.A former side slough,the head of this site has been filled in and revegetated.A side channel connects the slough to the mainstem Susitna River (Appendix Figure A-lOa).The substrate consists of approximately six inches of silt over large gravel and rubble.The shallow pool,at the mouth,is rimmed by littoral vegetation and a beaver lodge is found along the left bank.Above the pool,the channel A-l13 G WATER QUALITY MEASUREMENT SITE*INTRAGRAVEl TEMPERATURE SITE <JJ o Z50 I I FEET (Approx.Scale) :;e,. I I--' I--' +:> Beaver Dam <___ "~,,~~":~2:),I;'):;i·"i':.u.~;·\fi."'."~~4 :,!;,.:.t ,~ ED RM 139.0 /7 ~J;C"')R.J$.4.·~i::S~· -" "'sus/rNA R/VER Appendix Figure A-95.Channel geometry and sampling sites in Slough 17 (RM 138.9L). J 1 !J J )J )I t )~)~)1 ]I 1 ))J 1 j -J )'-j 1 J ']]l SUBSTRATE TYPES S 1-SIL Tj VERY nNE RU-RUBBLEi 3-5" Co-COBBLE i.5 -10" /-OVERLYING L.AY ER ___SEEPAGE ~UPWELliNG ~o 110I., FEET (Approll.Scale) _\.!:~••'l..'-,_/••...,1,~:"'.':',JI.ht,"-.~...-'"7"'_"~l ..~ .:~.. ..~.."'. -~' __.~_....~"'4~"';J·"'~ El)RM 139.0 ~........:.~~::.,\I .........;·:~~~·\:i~.·...~..,/_.'\:;..;~i/,::..:....... Seaver Dam ~-- ~ I.............. (Jl --~sus/rNA RIVER Appendix Figure A-96.Substrate composition and upwelling areas in Slough 17 (RM 138.9L). CHUM SALMON SPAWNING AREAS .1983 ~1984 <J] o 2&0 I ! FEET (Approi~Scale) i, 1- 'I ! ):> I I--' I-' O'l Blovlr Dam <__- EB RM 139.0 ..; "' ,~.'"....~f.£.~..g,~..!._\.,~!l .l'lo __t"'~.... SUSI rNA RIVER '.QI?''''''~~iJ)".$ly·u\_. Appendix Figure A-97.Chum salmon spawning areas in Slough 17 (RM 138.9L). )I ~~I J J )I J )I ~J ]I g J .t ~4 1 1 1 -)_.-::1 J SOCKEYE SALMON SPAWNING AREAS _1983 ~1984 <JJ o 250 L I FEET (Approlt.Scal') -~,;..9."f\"".4i ..~"_......_.....t..!""'i......f":~J"" ,,_0 1 ...:..;..·.·,J·\.!.,·,..j\\:\..•\..,....,,......:.:--.(••.•t .;C$""'." ,-_..... ';;&"-,A:~-::";~;'•• Slou .~.....~'.!_to.4 ••• '~...... I~, n,·....vC.·. (f)RM 139.0 B.all.r Dom <:::::::::::_ ):> I.................... J ~SUSI rNA RIVER Appendix Figure A-98.Sockeye salmon spawning areas in Slough 17 (RM 138.9L). o 120 I I FEET (ApprOI.Sea I.) <JJ CHUM SALMON SPAWNING AREAS .1984 sUeSTRATE lYPES SI-SILTi VERY FINE @ WATER QUALITY MEASUREMENT SITE •INTRAGRAVEL TEMPERATURE SITE )::- I.......... co ffi RM 139.0 \t:,:._..~... ~ ~-- .02. sus/rNA R/VER Dam Appendix Figure A-99.Substrate composition and spawning areas in Slough 18 (RM 139.1L). J I t I ,.~!..~J J I J )J J ~..~1 }} ....••,1. ".1 •.•••...~.•.J.\. ~. •••",..t 8 WATER QUALITY MEASUREMENT SITE*INTRAGRAVEL TEMPERATURE SITE ~ o 120 I I FEET (Approll.Scali) 84 ._'•••·.~••n.·ri /9 "-7'"r O *@3 " '0'".p_ ~IVE~---- *@.2*Gli .....,·~.!·:f_. ~5U5IrNA ffiRM)39.8 ·..·::..:·l.··.~·\·-fJ'=-~..~·...."'~.....~~''-1 ....-"'-,:;; J;::o I............ 1.0 Appendix Figure A-lOO.Channel geometry and sampling locations in Slough 19 (RM 139.8R). narrows and substrate changes to rubble/cobble/boulder.In the side channel,cobble/boulder predominates except for a pool at the junction of the side channel and the slough where large gravel and rubble can be found (Appendix Figure A-lOl). Upwelling and bank seepage is found in the lower reach of the slough. At low mainstem discharges,water is clearer and upwelling and bank seepage can be found in the side channel downstream of the slough (Appendix Figure A-102).Both sockeye and chum salmon utilize this slough for spawning (Appendix Figures A-103 and A-104).Fry are present in the slough,particularly in the pool at the mouth. Factors limiting spawning at this site are substrate and passage at low mainstem discharges. Slough 20 (RM 140.1R) Slough 20,located on the south bank of the Susitna River,is a single channel side slough approximately 0.5 miles long.The slough is separated from the mainstem Susitna River by a large vegetated island. Two tributaries flow into Slough 20 on the right bank.Waterfall Creek enters approximately 1,500 feet upstream from the mouth,and a small unnamed tributary enters near the head of the slough. At mainstem discharges exceeding 8,480 cfs,the backwater area extends approximately 300 feet into the slough with silt and sand predominating. Above the backwater area,Slough 20 consists of a series of pools and riffles.Substrate is composed of gravel/rubble with areas of cobble/boulder at the head.Pools contain deposits of silt and sand. The 250 feet run downstream of Waterfall Creek contains substrate of compacted angular shale that is different from what was found in the rest of the slough (Appendix Figure A-lOS).It is assumed that the presence of the shale was due to the erosion and deposition of Waterfall Creek.The gradient of Slough 20 is 13.5 ft/mi with a corresponding mainstem gradient of 13.4 ft/mi.Six passage reaches have been described in Blakely et ale 1985 and Sautner et al.1984 (Appendix Figure A-106). Spawning in Slough 20 occurs primarily in the first 900 feet of the slough with pink and chum salmon the primary salmon species (Appendix Figures A-l06 and A-107).Peak counts of 280 chum and 85 pink salmon were recorded,accounting for 3.7 and 8.0 percent respectively of the total slough spawning for each species. Problems limiting spawning in this site are passage at low mainstem di scha rges ,dewa teri ng of the upper 900 feet of the site and some substrate limitations. Side Channel 21 (RM 140.6R) Side Channel 21 is a relatively straight,single channel,approximately 0.9 mi long,located on the south bank of the Susitna River.It is separated from the mainstem by a series of well vegetated islands and gravel bars (Appendix Figure A-lOB).Several intermittent channels A-120 ~i J 1 J J )J o 120 I I FEET (Approx.Scalel 00 .•••-•••••~••i".• ~ SUBSTRATE TYPES S I •SIL Ti VERY FINE LG-LARGE GRAVEL;1-3" RU·RUBBLE;3-5" CO-COBBLEi 5-10" BO-BOULDER;>10" /.OVERLYING LAYER /9 .................!._!-c ~.':''f"~ir--;·"'' SI/LG-RU RiVER ----- ._1\l. ....::.. ••1"'"' J'''''J '#1·':" ~5U5IrNA $RM 139.8 _\"!_'_•••~, .;.;•.:........".\''1;1\;;...;,"".,0..-. 80 -CO ,.,.:;......~".1 ....._.... •·..~'•.i·(•.-••,.•';\•• » I ........ N ........ Appendix Figure A-IOl.Substrate composition in Slough 19 (RM 139.8R). ._"t.0 :o.._'!._·.s....:'->.......·\.... _...J"''''' -----PR PASSAGE REACH . o 120 i I FEET (Ap"prolt.Seale I PR~ -.-SEEPAGE ~UPWELLING \\\\\\\\~H~...\W~J ...o;;;..•..•..fi...f}. .It:~., i""l~",'~0' RIIIER ----- ,-) ~SIJSlrNA Ef)RM 139.8 ;r:. I...... N N Appendix Figure A-IO?Passage reaches and upwelling areas in Slough 19 (RM 139.8R). J 1 J I 1 I 1 !i §),I J 1 .~J 1 i _.~~~"O 1 J '" y } ~ o 120 I I FEET (Approx.Scole ) CHUM SALMON SPAWNING AREA$ run 1981 ~1983 ~1984 /9 ,,-_. ..,,-.-•....•. RiVER ---- ~F-' ~5U$lrNA .-.....~,. ..J ...... EB RM 139.8 . ~.•.••,_.~_"......._.__••.1 ......J.I'. '-"';;'-'.1 ""-"",. ·r: ~ I...... N W Appendix Figure A-103.Chum salmon spawning areas in Slough 19 (RM 139.8R). ~ o 120 I I FEET (Approx.Scale) SOCKEYE SALMON SPAWNING AREAS lIDll981 ~1983 ~1984 /9 ,,~.•....' ." RI'I tR ---- eRM 139.8 -_t ••••....~_"IIt.J.\•.1 ......·._.·.1 ...1.' ~SUSlrNIl •...;40·:~·4·....T.";i;. ,,' )::> ! l-' N .p. Appendix Figure A-I04.Sockeye salmon spawning areas in Slough 19 (RM 139.8R). ~.}.).~~,t !•t ~J ~1 t f ..~.• --~'}f~~Jl "~~~1 -1 1 NIVEN ______ ......--u't ..;••_~'•• RM 140.1 "'~.'."" -E '-.' ;......-••to·!..••O."·_,i·~t."...l',.t ••- sus;rNA "--', "t.,......•" ••~!Io SUBSTRATE TYPES LG-LARGE GRAVEL;1-3" RU -RUBBLE;3-5" CO-COBBLE;5-10" BO-BOULDER;>10" '.~..."'"c l'~.\.;J J "_~".".:;'_:.....,.~...,.'\," .:..'.....,~"'....ll.}".",i,.:t.;.iIJ "-:-'""•• '.'lot1.;··-"'..r,,' co -RU -B,O 2 0 .....,.....",~...'-."'......: RU-CO-LG &Waterfall Creek~ ....;;....".~ a 2~O 1 I FEET (Approlt.Scale) J;:o I t--' N 01 Appendix Figure A-I05.Substrate composition in Slough 20 (RM 140.IR). CHUM SALMON SPAWNING AREAS filii 1982mn1983 ~1984 -PR PASSAGE REACH .,~.. ~ '0'::,-.~'"••.•••.:.1 ••'J··.·t ......_.•~...~.'l.•• .,',-1.0',10 • ......:--:.'...."~.t...iS.'".,:.,\,otV>.J t'·;-'/V" NIVEN ........\,_.. .....~•.~..--PRllI r:Waterfall Creek •,_'•.j ·~.I'A'"..'••- -SUs/rNA •..••••W..2"~•_......~••!..._l...._••.'•• ~ ~ ~ .....~Il •••••,..'.!'_,.._~..loA ....,-• o 2~O I J FEET (Approll.Scali) (DRM 140.1 ~_"If'»~III~''-'_&."_1'-'< ::P I I-' Nen Appendix Figure A-I06.Chum salmon spawning areas in Slough 20 (RM 140.1R). ,)~'"I,•l J )J '.~) ,.. ~J.I t 1 ) -1 El)RM 140.1 o 2~O I I FEET (Approlt.Scale) .1981Em ~1982 PINK SALMON SPAWNING AREAS (!)WATER QUALITY MEASUREMENT SITE •INTRAGRAVEL TEMPERATURE SITE Ii,...-A ,-JJf-. i!._1 J.!.:'".•:~'J L'·-..·.0.:..-'•••.·I.).J.....'~"1<.' ...._••J ••0 .#.1....... •-"....~.~.,...i ...J\i:i".j'~1"'...·IVir NIVEN ____ 'j\,.:"'r ..··~-.·....-.7'" 'l!Waterfall Creek •la'''-~••t.-J"•••••'••- -SUS/TNA :,.~/20 ""0/1 g h .....t~'..-,..'~••ti",oo:.I·";1r·1.;,; ~4 '.0 ...+JO'.•__••_~:........_1.1i-·'" ~ ~ .-J "-0'._........ ......~•••#\,. :-",,,,,,u'_'l.~J··· );:- I...... N........ Appendix Figure A-I07.Pink salmon spawning areas in Slough 20 (RM I40.IR). <E ?'jO FEET • (Appro 11..Seol.1 .....r.:._. ·..·1·• .'t:......"..._..........::':".... ""'\\'.~ J'9/I""yC'~ c~ o"J"J t9 / R/ Gl WATER QUALITY MEASUREMENT SITE •INTRAGRAVEL TEMPERATURE SITE ~oS't/of/r..~.../11'4.,'., ........$'...- eRM 141.0 ~':.~·.ol:';·fN:.l~i:"';i)l""+o;-t·-:·4·oj"'.;;'I;~ ):;> I...... N 00 Appendix Figure A-lOB.Channel geometry and sampling sites in Side Channel 21 (RM 140.6R). "•• I )I l J J I'1 J J J I J 1 J ~'..~ r1 connect the side channel with the mainstem.The mouth of Slough 21 flows directly into the upper portion of Side Channel 21.Pools are located in the mouth and head areas.The backwater area extends approximately 1,500 feet into the side channel at mainstem discharges exceeding 16,000 cfs.Substrate composition in Side Channel 21 is predominantly cobble/boulder with silt/sand deposits in the mouth and pool areas (Appendix Figure A-109).The gradient of Side Channel 21 is 12.4 ft/mi with the corresponding mainstem gradient of 16.6 ft/mi. A total of nine passage reaches have been identified in this site and are discussed in detail by Blakely et ale 1985 (Appendix Figure A-110). Peak counts of 17 sockeye and 48 chum salmon were recorded accounting for 52 and 3.7 percent respectively of the total mainstem and side channel spawning.In general Side Channel 21,as part of the Slough 21 complex,is vitally important to sockeye and chum spawning activity both as a passage corridor to Slough 21 and as a spawning habitat (Appendix Figure A-Ill).Upwelling and bank seepage is limited and appears to be somewhat intermittent. Factors limiting spawning activity in this site are substrate and passage. Slough 21 (RM 141.8R) Slough 21 located on the south bank of the Susitna River,is approxi- mately 3,000 feet long and is separated from the mainstem by a large vegetated gravel bar.Approximately 1,500 feet upstream from the mouth, Slough 21 divides into two forks:a northwest (left)channel and a northeast (right)channel.The mouth of Slough 21 flows directly into the head of Side Channel 21 where a pool is formed (Appendix Figure A-1l2).No backwater has been observed in Slough 21.Cobble and boulder with silt/sand deposits in the pool areas are the predominant substrate types found in Slough 21 (Appendix Figure A-113).The gradient of Slough 21 is 22.9 ft/mi,with a corresponding mainstem gradient of 12.1 ft/mi.Passage probl ems exi st in thi s si te but the overriding control of fish movement into Slough 21 is passage within Side Channel 21.Four passage reaches have been identified in this slough as are found in Blakely et ale 1985 and Sautner et al.1984 (Appendix Figure A-114). Slough 21 is one of the three major spawning slollghs for sockeye and chum salmon on the Susitna River (Appendix Figure A-114).According to Barrett et a 1.1985 it accounted for 13.2 percent of the sockeye and 31.2 percent of the chum salmon slough spawning with peak survey counts of 122 and 2,354 fi sh respectively.Over the past four years (1981- 1984)Slough 21 has been responsible for 12.3 percent of the sockeye and 25.7 percent of the chum salmon slough spawning. Factors limiting spawning in this site are passage and substrate. Slough 22 (RM 144.2L) Slough 22 is a 0.5 mile long side slough located on the north bank of the Susitna River at RM 144.2.A clear water tributary entering along A-129 & y 4r FEET (Approx.Scal.) ~ ~/I/C';f> SU8STRATE TYPES LB-LARG E GRAVEL.1_3 11 RU-RUBBLEj 3-&11 CO-COBBLE;5-10" BO-BOULDERI :>10" c~q~~I1/ -.-SEEPAGE.-- UPWELLING ~S(/S~/1'"4'4 .!•.(.f.,•.Jt ...'~,\_~t~'",'_f_ ED RM 141.0 \:--.•••1/~(,·!:to!...~t~l_ ;r... g t-' Wo Appendix Figure A-lOg.Substrate composition and upwelling areas in Side Channel 21 (RM l40.6R). J 'I I J •J )1 ).J ._J B 1 •~_J ~,.~II --PR PASSAGE REACH PINK SALMON SPAWNING AREAS .1982 J::> I t-' W t-' ~;:.;.,1 ;\i·!i11'"t\j\j:r'iOI:d'r·i~,.:;·w ..'j\.;\..~ E9 RM 141.0 ~St/s~/7""",.., c~(1""./ ~/vC"'~ ,~ o 400 !I FEET (Approx.Scali) & Appendix Figure A-lID.Passage reaches and pink salmon spawning areas in Side Channel 21 (RM l40.6R). & o 400 I I FEET (Approl,Scole) ~ /tJ/yc/t' SALMON SPAWNING AREAS ~CHUM,1981-84 ~CHUM,1981IICHUM,1982 •CHUM,1983nmSOCKEYE,1981-1984 C'~ Ohh e / S'/O'e ~St/s~/r,yA,"..~-., ED RM 141.0 ~::..:.~xi '!\"!."~!~t..!,:·u.~ » 8 I-' W N Appendix Figure A-Ill.Chum and sockeye salmon spawning areas in Side Channel 21 (RM l40.6R). J I •)cJ "'•I J •J ~.,•I I J ) ED RM 142.0 ~ -l';1C:"'; -Slough RIV ERSU5IrN~ [!]WATER QUALITY MEASUI{EMENT SITE*INTRAGRAVEL TEMPERATURE SITE ~SUBSTRATE SAMPLE SITE ~..'::~ ..~,..t(Q)DATAPOD SITE.·.t.~···. ~ <J] o 300 I I FEET (Approx.SclIl.), :Po I ~.... W W Appendix Figure A-112.Channel geometry and sampling sites in Slough 21 (RM 141.8R). EaRM 142.0 ~ Slough ~SEEPAGE ~UPWELLING ··t-····,>..~··:t-:~·······~....:~.:.....~.~....~...~'}..·1..;...·-·'''':"'"_t~..:..•••••~ R/V ER sus/rNA ~UBSTRATE TYPES SA-SANDi FINE LG·LARGE GRAVEL;1-3" RU-RUBBLEj 3.~" CO·COBBLE j ~-10" BO-BOULDERj >10" ~ <J} o 300 I I FEET (Approll.Scal.) ):> I I-' W.p Appendix Figure A-113.Substrate composition and upwelling areas in Slough 21 (RM 141.8R). J J J .l J I •'i t J I t J 1 J ~I ~J --:--1 £c-~~1 -~ ED RM 142.0 ~ Slough RIV ER .:j'. s US I rN A CHUM,1981-84 CHUM,1983 only SOCKEYE,1981·84__::.to"" SALMON SPAWNING AREAS ~ ~ lOll .......,,~.-. ~ <Jj o 300,I FEET (Approl.Scal.) ~l~·t"'~","'":"'':-·· :P I t-' (.oJ (J1 Appendix Figure A-J.14.Chum and sockeye salmon spawning areas in Slough 21 (Rr1 141.8R). 1 the left bank approximately 600 feet below the head is the weakest and most seasonal of two tributaries and may be mainstem related.The second tributary,draining a bog area,enters about 1,000 feet below the head.It is tannin stained and flows constantly all year.Upwelling and bank seepage are evident in the middle reach and along the left bank in the mouth area (Appendix Figure A-lIS). Boulder/cobble substrate predominates in most areas,especially in the upper half where during unbreached conditions,the area is characterized by a shallow pool followed by a long riffle (Appendix Figure A-1l6). The lower half contains two deep pools that are separated by a riffle. The lower pool sometimes exhibits backwater characteristics and has boulder/cobble substrate covered by silt.The upper pool has large gravel/rubble substrates with a thin layer of silt. There are three passage reaches in this slough that can be restrictive to fish passage in an unbreached condition as is found in Blakely et a1. 1985 and Sautner et a1.1984 (Appendix Figure A-lIS).Chum and sockeye salmon spawned in this slough during 1983 and 1984 with the majority of spawning centered around the upper half of the second pool (Appendix Figure A-117).This pool has good upwelling as well as large gravel/rubble substrate.Fry are present throughout the site. Factors limiting spawning in this site are passage,substrate and ~imited upwelling. Slough 21A (RM 145.3R) This is a 0.75 mile side slough located on the east bank of the Susitna River at RM 145.3 with a small stream entering the slough about 0.2 miles below the head (Appendix Figure A-U8).The only observed bank seepage and upwelling in this slough appears at and slightly downstream of this inlet stream (Appendix Figure A-1l9).This upwelling was weak and stopped completely in late fall.Channel geometry is mainly rectangular in the upper reaches tending toward parabolic in the lower reaches.In general,cobble/boulder substrates predominate with pockets of rubble/cobble or small grave1/large gravel (Appendix Figure A-120). This slough has numerous passage problems,and dewaters completely at low mainstem discharges.During 1984,chum salmon spawning was observed in the upwell ing area below the inlet stream and in the mouth area (Appendix Figure A-121).Fry were nbserved in isolated pools that later dewatered completely. Problems limiting spawning in this site are passage,substrate,and dewatering of the slough. A-136 - - - -. - - :;.::. I....... W....... __C} o 320 I I FEET (Appro •.Sea I,) <JJ -PR PASSAGE REACH ~SEEPAGE ~UPWELLING rn WATER QUALlTV MEASUREMENT SITE*INTRAGRAVEL TEMPERATURE SIT~ Small Tributary ------SUSI rNA EBRM 144.5 RIVER Appendix Figure A-115.Upwelling areas,passage reaches,and sampling sites in Slough 22 (Rt~144.2L). Small Tributary :P I I-' Wco o 320 I I FEET (Approl.Scal.) <f] SUBSTRATE TYPES 51-SILTj VERY FINE LG·LARGE GRAVELj I-3" RU-RUBBLEj 3-5" CO-COBBLEj 5-10" BO-BOULD ER j >10" I -OVERLYING LAYER rttl SUS/rNA ;~t{;q f;; '.": 'i_!....!."-..~~\o..~~):....~ EBRM 144.5 R/VER L...:~;~.·.!....t··· ..,.,/..-'~.' Appendix Figure A-IJ6.Substrate composition in Slough ?2 (RM 144.2L). .1 ]..~!J J t t }.J I J J ~l _l!J =~C~--l Small Tributary _!.t:.~."t.,,~:,,~~. ':'1 :1:·' 22 .·~~..:~~i:;')',~~"'At;,;:".,t:J';'·{.l."'':'l'"''......~.....J.J,....... I:,r,t:=t~:f•.,;.-_\.~ 'jt.f,;••r:.,,:....:4l~..,l'V. ._.,';"""";-1"""5'·ough.•'~_"1··* SALMON SPAWNING AREAS mil CHUM.1983 ~CHUM.1984 ~PINK.1982nmPINK.1984<§J o 320 I I FEET (Approll.Scale) '.~...··C-~"";~~~i.'f~":'~t."'·I"~;U.;';·=:':.',~tI:.;~~~.~·~:t:-J~~...1i1\~~..l" :Po I........ W 1.0 ~ """SUSI rNA E!)RM 144.5 RIVER Appendix Figure A-II7,Chum and pink salmon spawning areas in Slough 2?(RM 144.2L). .........."uo!•. h ~'1.a ,..~ll·,..$r,·,;,·;Lt~t ..,•.• .".1., _.'_I'.I~',t. .'-!'''-".....\-....,,\•1.,,--:...'.1:../_'_'.\,.'_'..:.,-",,,"0 ••1 .~·_II~_·...t ••••_, ••01.1¥:~ EBRM 14fU5 SUSITNA RIVER )::> I l-' -P>o ."...~0."_._1 ~ ,~•.•~I-"~'".-,-.;I "~,..-,,,,,,,,,., -:"';10",. '~,I'~ •..·~·I~ o 1500 I J FEET (ApprOll.8oale) o WATER QUALITY MEASUREMENT SITE •INTRAGRAVEL TEMPERATURE SITE Appendix Figure A-118.Channel geometry and sampling sites in Slough 21A (Rt1 145.3R). ~1 t I J J ..~J )~...)J J J !J )J ~ ~....';";.·lb~>,,,.• ,:.....,~.''9._..'.,• 0,'••i\ji)jil!.,••):,.P.i:.....,'....',;';jWj'/'...,,',,,'g••'.'0;ji"tf,}I"_..;•.••;:;"~!;;"j /'j'',.';;;..;'.','I!I ;';j )'j",";,'I;"r ,',;!~ > I...... .p...... EBRM 145,~ ~ .-J ~'SUSI rNA ..-n';~~..•:.-.;''''••-'~'I .-ri".I RIVER '.'••••_..."'ir ......~••••'1 ..,t'I...·.·oj"'0 .::o.j, ~."~.~~~"'..::.a.....~T o SOO I I FEET (Approll,Scal') .......-SEEPAGE ~UPWELLING Appendix Figure A-119.Upwelling and bank seepage areas in Slough 21A (RM 145.3R). EBRM 145.5 4 sus/rNA R/VER :P I...... .po N BO'='CO ~ o 500 I I FEET (Approx.Scali) .~.-,"i"......-:........·t••-•.;",:ri;,. SUBSTRATE TYPE S SG-SMALL GRAVEL;1/4 -I" LG-LARGE GRAVEL;I-3" RU-RUBBLEi 3-5" CO-COBBLE'5-10","BO.BOULDERi :>10 '" Appendix Figure A-120.Substrate composition in Slough 21A (RM 145.3R). )J •J .~,J •)~J J i J J I ..~.~.~ ~CCl ~----=1 l~ •~.'...~.~....i"...... ..'~I••~t ... "_'J~••-••_.-.• EBRM 14tU~SUSlrNA RIVER ·-'-"'-'''·-'i1 .i7;;;;;t,-21:4""" CHUM SALMON SPAWNING AREAS Il1llJ 198 I ~1984 •·I".~T.-· ~ o SOO I I FEET (Approll.Scal.) » I ~ +=>w Appendix Figure A-121.Chum salmon spawning areas in Slough ?lA (RM 145.3R). APPENDIX B GENERAL SURFACE WATER QUALITY AND INTRAGRAVEL TEMPERATURE DATA. B-1 '~~~1 Appendix Table B-1.General surface water quality measurements and intragravel water temperatures in selected sloughs and side channels in the middle reach of the Susitna River,1984. Surface Water Quality Intragravel Discharge Site Date Sample Temperature Dissolved Conduc-Water Temperature at (River Mile)Sampled location (OC)Oxygen tivity pH (Oe)Gold Creek (mgl1 )(field)(cfs) (umhos/cm) Slough 1 8-5-84 Mouth 11.4 7.1 132 6.4 -21,100 (99.5R)Middle 11.4 7.5 115 6.3 Head 9.1 5.9 111 6.0 Slough 2 8-5-84 Mouth 6.2 6.6 179 6.1 5.4 21,100 (100.7R)Middle 6.2 5.9 175 6.3 6.1 Tributary 8.9 5.8 168 6.2 7.2 Head 9.6 2.1 329 6.2 6.9 Whiskers Creek 8-15-84 Mouth 13.5 11.0 26 6.9 11.6 Slough Middle 12.1 10.6 21 6.4 11.7 (101.2L)Whiskers Creek 11.8 11.1 17 6.8 11.2 Middle 11.9 8.4 67 6.5 10.5 Head 7.5 4.6 61 6.8 8.5 Slough 3B 8-15-84 Mouth 11.6 7.5 70 7.0 10.1 15,100 o:l (101.4l)Middle 10.7 7.6 64 6.8 10.5 I N 8-5-84 Mouth 13.3 7.9 160Slough3A 6.6 9.6 21,100 (101.9l)Middle 12.4 6.1 112 6.1 11.4 Middle 6.8 2.5 78 6.3 5.6 Middle 7.4 5.5 68 5.9 6.4 Head 7.4 5.9 69 6.1 6.4 8-15-84 Mouth 5.2 2.5 82 6.7 -15,100 Middle 6.2 5.4 72 6.7 Middle 5.7 4.4 56 6.7 Head 6.3 4.9 68 6.6 Slough 4 8-15-84 Mouth 4.0 -48 4.2 4.4 15,100 (10S.2R) Appendix Table B-1 (Continued). Surface Water Quality Intragravel Discharge Site Date Sample Temperature Dissolved Condue-Water Temperature at (River Mile)Sampled Location (OC)Oxygen tivity pH (OC)Gold Creek (mg/l)(field)(efs) (umhos/cm) Slough 5 8-4-84 Mouth 14.7 8.4 81 6.3 -20,000 (107.6L)Middle 15.0 7.9 67 6.3 - 10-8-84 Mouth 4.1 10.5 90 6.1 6.3 6,600 Middle 4.9 11.7 83 6.2 5.5 Head 4.9 11.2 71 6.5 5.3 Slough 6 8-4-84 Mouth 14.9 8.6 30 6.1 -20,000 (108.2L)10-8-84 Mouth 4.0 13.1 56 6.2 5.5 6,600 Middle 4.0 12.6 55 6.2 4.8 Oxbow I Side Channel 10-8-84 Mouth 3.3 10.6 176 6.2 5.2 6,600 (110.1L)Middle 3.1 9.9 128 6.2 4.6 Middle 3.5 11.5 107 6.3 4.7 Head 3.2 6.9 62 6.1 5.0 Slough 6A 8-3-84 Mouth 12.3 8.1 43 6.2 -20,400 OJ (112.3L)Middle 13.6 8.5 45 6.1 - I 10-8-84 Mouth 2.9 13.0 61 6.3 5.1 6,600wMiddle2.7 13.8 53 6.5 4.0 Middle 3.6 12.1 90 6.3 5.2 Head 5.1 1.7 182 6.2 5.9 Slough 7 8-3-84 Mouth 10.4 5.5 99 6.0 7.9 20,400 (113.2R)Middle 11.4 6.9 94 3.7 7.5 10-6-84 Mouth 6.4 13.8 71 6.5 5.7 6,780 Middle 5.3 10.6 69 6.4 6.3 Slough 8 8-3-84 Mouth 9.6 9.7 60 6.5 -20,400 (113.7R)Middle 8.8 8.1 69 6.2 4.5 Head 9.4 6.3 86 5.8 4.4 10-6-84 Mouth 5.3 11.8 76 6.2 5.0 6,780 Middle 5.1 13.7 73 6.3 4.4 Middle 5.1 9.5 88 6.3 4.2 Head 5.0 8.8 90 5.2 4.6 B ..I 1 ..._]-.J J J J )J J J )", JI :"::---"1 Appendix Table B-1 (Continued). ---] Surface Water Quality Intragravel Discharge Site Date Sample Temperature Dissolved Conduc-Water Temperature at (River Mile)Sampled Location (OC)Oxygen tivity pH (OC)Gold Creek (mg/l)(fiel d)(cfs) (umhos/cm) Mainstem 2 Side Channel 10-5-84 Middle 3.2 14.2 117 --7,080 (114.5R)Middle 4.8 14.3 114 6.7 Head R 3.5 14.4 139 Head L 3.2 14.8 149 6.3 4.7 Head L 3.5 14.9 173 6.3 Bushrod Slough 8-3-84 Mouth 7.5 10.0 29 6.3 4.5 20,400 (117.9L)Middle 7.1 9.6 97 6.4 5.4 Middle 7.6 7.9 109 6.3 7.2 Head 7.3 9.0 105 6.4 6.4 10-5-85 Mouth 2.9 13.4 191 -4.5 7,080 Middle 2.5 12.5 84 -4.0 Middle 2.5 11.6 109 -4.0 Head 3.3 11.2 93 -5.1 Trib 5.2 9.6 62 -6.1 OJ Curry Slough 8-3-84 Mouth 6.5 10.7 53 6.2 6.1 20,400 I (119.7R)Middle 5.9 10.0 51 6.1 7.3~Head 5.4 9.7 51 5.9 5.3 10-5-84 Mouth 2.5 15.7 54 6.3 3.3 7,080 Middle 1.4 14.8 56 -5.1 Head 2.4 14.2 58 -4.6 Slough 8C 8-16-84 Mouth 9.4 8.1 115 6.9 9.4 14,500 (121 •8R)Middle 6.9 7.2 92 7.0 7.0 Head 8.1 7.3 111 7.0 7.7 8-28-84 Mouth 3.6 9.9 77 5.7 3.9 21,000 9-13-84 Mouth 6.2 -107 -6.4 9,000 Middle ----5.1 Head ----4.8 10-4-84 Mouth 5.0 8.9 104 -5.1 7,380 Middle 4.2 9.2 65 6.7 3.4 Head 6.1 11.2 101 6.8 6.1 Slough 80 8-2-84 Mouth 8.5 10.9 34 6.3 7.0 22,000 (121.8R)Middle 8.5 10.5 33 6.2 8.4 Head 8.1 10.6 29 5.1 6.2 10-4-85 Mouth 5.2 14.0 50 -5.4 7,380 Middle 6.1 13.7 49 6.8 5.2 Appendix Table 8-1 (Continued). Surface Water Quality I ntragrave 1 Discharge Site Date Sample Temperature otssolved COnduc-Water Temperature at (River Mile)Sampled Location (OC)Oxygen tivity pH (OC)Gold Creek (mg/1 )(fiel d)(cfs) (umhos/cm) Slough 88 8-13-84 Mouth 5.2 6.3 182 5.8 4.1 17,600 (122.2R)10-4-84 Mouth 4.3 13.4 128 -4.3 7,380 Middle 4.0 13.4 132 -5.9 Middle 5.3 10.4 123 -5.7 Head 3.2 10.5 172 -4.0 Moose Slough 8-2-84 Mouth 8.8 7.8 200 6.3 8.8 22,000 (123.1R)Middle 8.7 7.0 182 6.7 9.2 Head 11.0 6.6 157 5.7 11.2 10-4-84 Mouth 5.8 13.8 216 -4.2 7,380 Middle 3.7 14.2 212 -4.5 Middle 5.1 11.6 212 -5.9 Head 7.0 6.3 181 -7.6 Slough AI 8-2-84 Mouth 9.1 9.2 87 7.1 5.5 22,000 (124.6R)Head 9.1 9.3 71 6.8 4.8 10-4-85 Middle 2.4 14.7 117 -3.3 7,380 Middle 4.3 13.6 115 -5.3 co Head 4.4 12.7 114 -5.8 I ()"1 Skull Creek 8-2-84 Mouth 8.7 11.5 63 6.9 9.2 22,000 Mouth 8.7 11.9 60 7.0 9.3 10-4-85 Mouth 2.6 15.1 117 -3.5 Middle 2.5 14.8 118 -3.4 Slough A 8-2-84 Mouth 9.5 8.2 79 6.0 7.8 22,000 (124.8R)Middle 8.7 10.2 66 6.5 8.9 Middle 9.5 7.1 90 6.2 9.6 Head 9.2 6.9 86 5.9 7.3 10-4-84 Mouth 3.3 11.8 109 5.3 5.8 7,380 Head 2.5 13.2 106 5.9 6.6 Slough 8A 10-4-85 Mouth 2.0 14.6 132 6.7 2.9 7,380 (125.3R)Middle 3.0 12.8 127 6.7 5.1 Middle 2.0 7.1 230 6.4 4.0 Middle 1.3 12.3 104 6.8 3.6 Head 1.4 13.4 94 6.8 3.8 J ,))~.~cl )t '.J -.~.1 )J J 8 I Appendix Table 6-1 (Continued). nl -:3 ~ Surface Water Quality Intragravel Discharge Site Date Sample Temperature Dissolved Conduc-Water Temperature at (River Mile)Sampled Location (OC)Oxygen tivity pH (OC)Gold Creek (mg/l )(field)(cfs) (umhos/cm) Slough B 8-2-84 Mouth 9.8 10.1 165 6.9 8.8 22,000 (126.3R)Middle 10.1 9.9 159 6.7 6.3 Middle 10.6 10.7 139 6.9 10.4 Head 6.3 7.4 243 6.5 4.1 10-4-84 Mouth 5.7 12.1 294 6.0 4.2 7,380 Middle 3.6 12.8 310 -5.9 Head 3.1 13.2 262 -4.7 Slough 9 9-12-84 Mouth 8.7 12.6 193 6.3 7.7 9,000 (128.3R)Middle 7.0 10.5 130 6.2 5.3 Head 8.1 14.0 130 6.8 6.8 10-3-84 Mouth 5.3 13.4 96 6.7 5.6 7,680 Head 5.8 10.7 120 6.7 4.5 Slough 96 8-11-84 Mouth 10.2 9.1 157 6.9 -22,500 (129.2R)9-12-84 Mouth 5.6 10.4 183 6.2 7.5 9,080 Middle 4.6 7.9 180 6.2 5.3 OJ Head 4.5 7.5 174 6.4 5.4 I 10-3-84 Mouth 5.6 10.6 163 6.6 6.6 7,6800'1 Middle 5.3 9.6 162 6.9 5.4 Head 5.0 8.4 162 6.5 5.0 Slough 9A 10-3-84 Mouth 4.3 15.1 183 6.6 5.2 7,680 (133.2R)Middle 4.0 12.9 189 6.8 4.0 Head 4.7 11.7 207 6,6 4.1 Slough 10 10-3-84 Mouth 2.7 11.3 183 6.7 4.3 7,680 (l33.8L)Middle 2.6 11.8 210 6.8 3.3 Middle 2.6 12.0 205 6.8 3.4 Middle 2.8 10.4 158 6.8 3.7 Head 2.9 9.8 148 6.8 3.5 Slough 11 10-2-84 Mouth 5.0 13.3 235 7.0 4.7 7,980 (135.3R)Middle 5.0 13.5 237 7.0 5.1 Head 4.4 12.6 238 6.9 4.6 Slough 12 8-1-84 Mouth 13.0 9.0 113 6.6 11.6 23,400 (135.4R)10-2-84 Mouth 7.4 12.3 158 6.8 6.8 7,980 Middle 6.8 11.1 130 7.0 6.8 Appendix Table B-1 (Continued). Surface Water Quality Intragravel Discharge Site Date Sample Temperature Dissolved Conduc-Water Temperature at (River Mile)Sampled location (OC)Oxygen tivity pH (OC)Cold Creek (mg/l)(field)(cfs) (umhos/cm) Slough 13 8-1-84 Mouth 12.9 10.9 68 7.0 10.7 23,400 (135.5R)Middle 4.8 8.9 174 6.9 4.5 Middle 5.6 10.0 184 6.9 6.6 Head 5.7 10.9 194 7.0 5.9 Upper Side Channel 11 10-2-84 Mouth 6.6 12.2 165 6.7 5.6 7,980 (136.0R)Middle 6.6 9.7 198 6.5 3.9 Head 9.1 14.1 257 6.7 5.5 Slough 14 8-1-84 Mouth 10.9 8.5 35 6.0 8.8'23,400 (136.0l)Middle 12.6 5.3 71 6.0 10.0 10-2-84 Mouth 6.4 10.6 44 6.5 8.9 7,980 Middle 8.4 4.3 76 6.3 8.6 Head 6.9 7.3 72 6.7 7.3 Slough 15 8-1-84 Mouth 10.7 5.7 90 6.3 6.6 23,400 OJ (137.2l)Middle 10.6 9.0 23 6.2 11.2 !Head 10.4 8.6 28 6.0'-.J 10-2-84 Mouth 5.9 9.9 37 6.2 6.2 7,980 Middle 6.8 9.2 56 6.6 6.2 Slough 16 10-2-84 Mouth 6.2 7.8 51 6.6 7.0 7,980 (137.7l)Middle 5.6 5.6 52 6.1 5.2 Head 5.3 13.5 56 6.6 5.3 Slough 16B 10-2-84 Mouth 4.7 12.0 56 6.5 8.0 7,980 (137.9l)Middle 5.7 10.8 56 6.6 5.4 Head 5.0 9.6 61 6.4 5.8 Slough 17 8-1-84 Mouth 4.8 8.4 57 6.1 5.3 23,400 (138.9l)Middle 4.4 8.8 53 6.0 3.5 Middle 6.9 7.0 61 6.{)7.6 Middle 12.0 3.6 67 5.8 13.0 Head 4.8 8.3 57 6.2 5.0 9-11-84 Mouth ----5.0 9,330 Middle ----5.1 Middle Middle ----4.9 Head --- -4.2 J J J j J ~t j J J ~,J J i ))) "'~l -1 =-:-=-} Appendix Table B-1 (Continued). Appendix Table B-1 (Continued). Surface Water Quality Intragravel Discharge Site Date Sample Temperature D~ssolved Conduc-Water Temperature at (River Mile)Sampled Location (OC)Oxygen tivity pH (OC)Gold Creek (mg/l)(fiel d)(cfs) (umhos/cm) Slough 21 8-30-84 Mouth 4.6 11.3 197 6.7 3.6 15,300 (141.8R)Middle 4.3 11.3 192 6.6 3.5 Middle 4.5 10.0 195 6.6 3.2 Head 4.1 9.9 196 6.7 3.3 10-1-84 Mouth 6.1 16.6 152 7.6 6.0 7,830 Middle 3.5 12.8 195 7.2 4.2 Middle 3.5 10.1 197 7.2 4.1 Head 3.6 12.8 199 7.2 4.1 Slough 22 8-30-84 Mouth 4.5 12.0 88 5.9 4.8 15,300 (144.2L)Middle 4.8 11.9 78 6.1 3.7 Middle 5.5 13.9 36 6.3 5.8 Middle 5.8 13.6 31 6.8 6.0 Head 5.4 13.1 101 6.4 5.8 10-1-84 Mouth 4.9 9.9 162 7.1 6.5 7.830 Middle 4.1 8.6 122 7.1 5.0 Middle 5.4 13.1 68 7.2 6.3 a::J Middle 5.9 12.7 69 7.1 6.7IHead3.7 8.8 109 7.0 4.91.0 Slough 21A 7-31-84 Mouth 10.8 11.5 113 7.0 11.2 25,300 (145.3R)Middle 10.4 10.8 119 6.1 2.7 Middle 8.1 10.5 129 6.1 3.9 Head 9.9 12.0 146 6.3 5.2 10-1-84 Mouth 3.1 9.5 183 6.9 5.5 7.830 -,J J ,)I j J I 1 .~i ~_J ~J 1 T APPENDIX C SALMON SPAWNING DISTRIBUTION DATA. C-1 ~~-..-=J -1 ~ Appendix Table C·1.Salmon spawning distribution in the middle reach of the Susitna River,1981 -1984 (adapted from Barrett et al. 1985).. 1981 1982 1983 1984 Site Chi-Sock-Chi-Sock-Chi-Sock-Chi-Sock- (River Mile)nook eye Pink Chum Coho nook eye Pink Chum Coho nook eye Pink Chum Coho nook eye Pink Chum Coho Slough 1 M X X (99.5R) Slough 2 X X X M X (100.7R) Wiskers X X X X (101.2L) Slough 36 X X X X X X X (101.4L) Slough 3A X M X X X (101.9L) Slough 4 n (105.2R) I N Slough 5 M X X (107.6L) Slough 6 M M M (108.2L) Oxbow I X (110.1L) Slough 6A M M M M M M M (112.3L) Slough 7 (113.2R) Slough 8 X X X X (113.7R) X -Spawning observed M-Milling observed,no spawning observed Appendix Table C-1 (Continued). 1981 1982 1983 1984 Chi-Sock---Chi-Sock---Chi -Sock---Chi-Sock--- Site nook eye Pink Chum Coho nook eye Pink Chum Coho nook eye Pink Chum Coho nook eye Pink Chum Coho (River Mile) Mainstem II X X X X (114.5R) 8ushrod X X (117.9L) Curry X (119.7R) Slough 80 X X X X (121.8R) Slough 8C M X X M X (121.8R) Slough 88 X X X X X X (122.2R) n I Moose X M X X M X X M X X X X Mw (123.1R) Slough AI X X X X (124.6R) Slough A M X M X (124.8R) Slough 8A X X X X X X X X M X M X X X (125.3R) Slough B X X X X X X X (126.3R) Slough 9 X X X X X X X X M X (128.3R) -- X -Spawning observed M -Milling observed,no spawning observed J ))1 }J ~I )J !!J J J ) ::::~~i Appendix Table C-1 (Continued). ---:-1 ~ 1981 1982 1983 1984 Chi~Sock---Chi-Sock---Chi-Sock---Chi-Sock---- Site nook eye Pink Chum Coho nook eye Pink Chum Coho nOQk_~e Pink Chum Coho nook Elye Pink Chum Coho (River Mile) Slough 96 X X X X X X (129.2R) Slough & S.C.10 M X M X X M (133.8L) Slough 9A X X X X X X X (133.2R) Slough 11 X X X M X X X M X X X M X X X (135.3R) USC 11 X X X M X X X M X X M X M (136.0R) Slough 12 n (135.4R) I +::>Slough 13 M M X (135.5R) Slough 14 X (136.0L) Slough 15 M M M M M X X X X M (137.2L) Slough 16 X X (137.7L) Slough 16B X (137.9L) Slough 17 X X M X X M X X M X M X (138.9L) X -Spawning observed M-Milling observed,no spawning observed Appendix Table C-1 (Continued). 1981 1982 1983 1984 Chi-Sock---Chi-Sock---Chi-Sock---Chi-Sock--- Site nook eye Pink Chum Coho nook eye Pink Chum Coho nook eye Pink Chum Coho nook eye Pink Chum Coho (River Mile) Slough 18 X X (139.1L) Slough 19 X X X M X M X X X (139.8R) Slough 20 M X X X X M X X X (140.1 R) Slough & S.C.21 X X X X X X M X X X X (140 .6R) Slough 22 X X X (144.2L) Slough 21A X X n (145.3R) I U1 X -Spawning observed M-Milling observed,no spawning observed }-~~),I .1 J ,I J J ..~J •J ~D .,... I APPENDIX D SELECTED PHYSICAL AND CHEMICAL REQUIREMENTS FOR VARIOUS LIFE STAGES OF SALMON SPECIES. [\-1 ~1 ~~ Appendix Table 0-1.Water temperature,dissolved oxygen,pH and substrate requirements for various life stages of salmon species. 10.1 optimum value :::::I I N Life Stage Upstream Migration Spawning Species Chum Chum Parameter Water Temperature (OC) Water Temperature (OC) Observed Values 4.4 -19.4 8.9 -14.4 5.0 -12.8 10.0 -16.7 8.3 -21.1 0.0 25.6 6.5 -12.5 13 2.5 1.8 -8.2 5.0 -6.0 7.2 -12.9 9.5 -12.8 9.0 -10.0 ca.6.0 2.0 -9.0 Remarks total range range during peak migration range during upstream migration during peak of upstream migration range for the species lower and upper lethal 1 imi t most spawning inhibited spawning behavior most spawning suggested criteria for species mean temperatures,sUlwner chum sUlIIRer chum autumn chum bottom water Location Traitors River Tributaries of Kuskokwim River Anvik River ,. Terror &Kizhuyak Rivers Sashin Creek Big Bear Creek, Washington Sakhalin,USSR South Kuril Island, USSR Amur River,USSR Amur River,USSR Iski River,USSR Reference Mattson &Hobart (1962) AOF &G (1980a) Trasky (1974) Bell (1973) Wilson et al.(1981) McNeil (1964) Schroder (1973) Rukhlov (1969a) Ivankov &Andreyev (1971) Bell (1973) Soin (1954) Sano (1966) Smirnov (1947) Appendix Table 0-1 (Continued). Life Species Parameter Observed Remarks Stage Values Water Spawning Chinook Temperature 3.3 -13.3 range for species (OC) Pink (cont'd)7.2 -15.6 range for species COho 7.2 -15.6 range for species Sockeye 7.2 -15.6 range for species Locati on Reference Bell (1973) Bell (1973) Bell (1973) Bell (1973) CJ I W Spawning Chum Substrate Particle Size gravel 2 - 3 cm in diam.,also use coarser stones and bedrock covered with small boulders gravel mostly 1.27 -127.0 cm with variable amount fines stones 1.3 - 13.0 cm,coarse sand,fi ne sand and silt gravel I 2.69 cm (98%) gravel II 1.35 - 7.61 cm (97%) gravel III 0.67 - 2.69 cm (96%) gravel IV 0.02 - 0.67 cm (96%) spawning grounds gravel sizes II and III selected by 75%of spawning females; gravel I selected by 20%, gravel IV selected by 5% Alaska ., Delta River Hooknose Creek, Big Beef Creek .Morrow (1980) Francisco (1976) Hunter (1959) British Colombia Duker (1977) J I ,I j ~i J ,J I ,•!)~I )I Appendix Table 0-1 (Continued). ------J -J ~ Cl I .j::> Life Stage Spawning Species Chum Parameter Substrate Particle Size (cont'd) Observed Values 1.3 -10.2 em gravel mixed with small amount of silt "sand"(0.8 - 52.811I,avo 12.0 -12.711I) "gravel"(10.0 - 50.1%,avg. 33.0 -45.990) "shingle"(6.0 - 84.190,avg. 41.4 -44.490) "sand"(14 - 2211I) 0.5 em (2511I), 0.6 -3.0 cm (45%),3.1 cm (30%) Remarks substrate size criteria for species decreased survival to emergence Locati on Amur River, spawning grounds Sakhal in Northern Japan Reference Bell (1973) Soin (1954) USSR Sakhalin Rukhlov (1969b) Rukhlov (1969b) Sano (1959,cited by Bakkala,1970) subsize criteria for Bell (1973) species subsize criteria for Bell (1973) species subsize criteria for Bell (1973) speci es subsize criteria for Bell (1973) species particles 0.5 cm (always 20%) particles 3.0 em (25 -5390) Chinook 1.3 -10.2 cm Pink 1.3 -10.2 cm Coho 1.3 -10.2 cm Sockeye 1.3 -10.2 cm spawning grounds Memu River, Japan Sano &Nagasawa (1958) Appendix Table D-1 (Continued). Life Stage Species Parameter Observed Values Remarks Location Reference o I 01 Intragravel Chum Development Water Temperature. (DC) 0.5 -4.5 2.0 -4.2 3.6 -4.5 2.0 -4.5 0.2 -10.0 0.0 -4.0 0.4 -6.7 4.4 -13.3 4.4 higher mortality at lower range emergence delayed b~yond that of wild fry incubated at 3.9DC probe 20.3 cm deep suggested criteria for species lowest temp.prior to closure of blastopore (Pacific salmon). can go as low as ODC and still have good survival. Chena River Cl ear hatchery Noatak River Olsen Creek Delta River Kogl (1965) Raymond (1981) Merritt &Raymond (in prep.) Bailey (1964) Francisco (1977) Bell (1973) McNeil &Bailey (1975) 3.5 -5.0 3.9 -4.9 2.4 -3.0 Chinook 5.0 -14.4 Pink 4.4 -13.3 Coho 4.4 -13.3 Sockeye 4.4 -13.3 range.fertilization to emergence egg stage alevin stage suggested criteria for species suggested criteria for species suggested criteria for species suggested criteria for species Bira River.USSR Bolshaia River. USSR Disler (1951) Semko (1954.cited by Sana.1966) Bell (1973) Bell (1973) Bell (1973) Bell (1973) J J ,J ~)J )1 I 1 I I J J _I ==3 Appendix Table 0-1 (Continued). .~~.._.J Life Speci es Parameter Observed Remarks Location Reference Stage Values Intragravel Chum Substrate fines 0.0833 em poor quality substrate Pri nee Wi 11 i am Thorsteinson (1965) Development Particle (12.7%)Sound Size silt and sand (6%).redds tributaries of Burner (1951) 15 em (81%).lower Columbia 15 em (Bill)River 5.1 -10.2 em greater survival to Robertson Creek.Dill &Northcote (1970) 1.0 -3.8 em emergence in larger British Columbia gravel sand.0.0105 -lower survival to Big Beef Creek.Kosk i (1975) 0.3327 em (ca.5 -emergence and smaller Washington 50%)fry at higher percentages CJ mostly 0.2 -1.0 redds -also.redds Sakhalin Rukhlov (1969a) I em,some par-had less of the O'l ticles 2.0 cm 0.025 -0.1 em fractions,but more sand and mud than spawning gravel "sand"(1.8 -redds Sakhalin Rukhlov (1969b) 30.011I),avg. 10.0 -13.5%) "gravel"(13.4 - 60.0%.avg.33.5 -40.3%) II shi ng 1e"(13.7 - 75.9%,avg.39.2 - 53.0%) 10 em (0.0 - 50.0%,avg. 0.7 -9.5%) Chinook 14%6".80 96 6"redds Tributaries of lower Burner (1951) 6%silt-sand Columbia River Appendix Table D-l (Continued). Life Stage Species Parameter Observed Values Remarks Location Reference Intragravel Coho Development Sockeye Chum Dissolved Oxygen. mg/l 10%6".85%6" 5%silt-sand 0.5%6".92%6" 7.5%s11 t-sand 2.0 0.6 -3.0 2.8 -6.5 2.1 -4.1 redds redds good survival of eggs and alevins (strong flow of groundwater) low survival high survival smaller alevins produced at lower end of range Tributaries of lower Burner (1951) Columbia River Tributaries of lower Burner (1951) Columbia River Chena River Kogl (1965) o I -...I 0.0 -12.7 5.4 -8.9 1.77 -6.80 3.6 -8.3 2.0 5.0 8.0 2.0 6.0 -8.0 annual range September and November July -September.lowest caused by long dry period upper intertidal area July -September.low percent survival at low end of range lethal limit for eggs low desirable good survival of eggs and and alevins as long as there is a strong ground water outflow most favorable level for entire development period of embryos and larvae at 4-8°C Twelvemile Creek Indian Creek Traitors River Olsen Creek British Columbia Amur River,USSR N.Okhotsk.USSR McNeil (1962) Mattson et al.(1964) Bailey (1964) Wickett (1957) Levanidov (1954) Lukina (1973) j t J .j J .~.J J -~I .J .1 1 i f J I I I '~-}··~-l Appendix Table 0-1 (Continued). Life Speci es Parameter Observed Remarks location Reference Stage Values Intragravel Chum Dissolved 3.0 -4.0 lowest value in redds Bira River,USSR Disler (1951) Development Oxygen, mg/l 0.72 critical value at 0 days Wickett (1954) 1,67 critical value at 5 days 1.14 critical value at 12 days 3.70 critical value at 85 days 0.4 -1.4 50\lethal limit for Alderice (1958) incubating chum All Species 7.0 or 90\sat.Hatchery criteria ADF &G (1983) 0 Chum pH 6.5 intragravel Chena River Kogl (1965) I co "slightly acidic"intragravel Amur River,USSR Levanfdov (1954) 6.3 -6.5 intragravel Kobayashi (1968) All 5.0 -9.0 Range Doudoruff (1957) Species 6.0 -8.0 Preferred range Ba 11 ey (1975) 6.5 -8.0 Hatchery criteria ADF &G (1983) Water Emergence Chum Temperature 3.0 -5.5 emergence and out-Delta River Raymond (1981) and (OC)migration Downstream 5.0 -7.0 range during peak of fry Salcha River Trasky (1974) Migration outmigration 6.7 -13.3 preferred range for Bell (1973) species 8.0 -10.0 preferred temp (over the Amur River,USSR Levanidov (1954) range 5.2 -19.0 °C) 15.0 survive Appendix Table 0-1 (Continued). Ufe Species Parameter Observed Remarks Location Reference Stage Values Emergence Chum Water 4.5 -5.5 outmigration Bolshaia River,Semko (1954,cited and Temperature USSR by Sano,1966) Downstream (0C) Migration 7.3 -23.8 preferred range Dill &Northcote (1970) Chinook 25.0 -15.0 upper lethal limit Barns (1967) and optimum 7.4 -25.1 preferred range Dill &Northcote (1970) Pink NA -23.9 preferred range Dill &Northcote (1970) Coho 6.4 -25.0 preferred range Dill &Northcote (1970) Sockeye 6.7 -24.4 preferred range Dill &Northcote (1970) 0 H !.O .1 1 I I j J I J J I J I !J ~J ,_I 5 Appendix Table 0-2.Literature review of salmon redd depths by species in Alaska and the Pacific Northwest. Redd Depth Life Stage Species (em)Remarks Location References Spawning Chinook greater than 35 Alaska Morrow,J.E. (1980 ) 30.5 Canada Scott and Crossman (1973 ) Sockeye 25 Frazer River,B.C.Cooper (1965) Canada up to 40 Alaska Morrow,J.E. (1980 ) 5.1 -10.2 Kokanee Canada Scott and Crossman (1973 ) 20 -25 Iliamna Lake,Olsen,J.C. Alaska (1968 ) Pink 17.8 -25.4 Southeast,Alaska McNeil (1962) (Hollis area) 7.62 -38.1 Southeast,Alaska McNeil and Ahnell (Hollis area)(1964 ) 0 I 25 Frazer Rivdr,B.C.Cooper (1965)I-'a Canada up to 45.7 Alaska Morrow,J.E.(1980) up to 45.7 Alaska/Canada Krueg.r,S.(1981) up to 45.7 Canada Scott and Crossman (1973 ) Chum 15 -30 Alaska Bakkala (1970) 8 -43 Ha 1e (1981) 20 -40 Noatak River,Merritt,M.F.and Kotzebue Sound,J.A.Raymond Alaska (1982 ) Appendix Table D-2.Continued. '='I I-' I-' life Stage Spawning Species Chum Coho Redd Depth (cm) 20 -30 up to 40 40.6 20 -25 25 Remarks Location Susitna River) Alaska Alaska Washington Alaska Oregon coastal streams References Roth)Kent (pers.comm.) (1984 ) Morrow)J.E.(1980) Scott and Crossman (1973 ) Morrow)J.E.(1980) Ringler N.H.and J.D.Hall (1975 ) .~I J J ,J ,J I ·1 1 J J J ~J B J APPENDIX E WINTER WATER QUALITY DATA. E-l Appendi~Table E-l.Intragravel and surface water quality data coll~cted a~standp ipe local.ions al 8ushrod Slough (RM 117.9L),Curry Slough (RM 119.7R)and Slough 10 (RM 139.8L)from November 1984 to May 1985,Sua it ina River.Alas...'" ------------------------------------------------------------------------------------ ~Dtr.gr.vel V.ter Surface Vater ------------------- Sampling 00 DO Sit"Standpipe -------Temp.Conduct iv ity T....p.Conductivity (River Kile)No.Date Time (C)("",11)'Sat.pH (UIlIboa/cm)(C)(mg/l)'Sat.pH (UIlIhoal em) (y/./d) --------- Suahrad Slough 001 841129 1418 (I17.9L)002 841129 1418 4.8 7.8 65 &8 4.5 7.5 62 64 003 841129 1418 3.1l 7.8 62 85 3.1 6.4 51 103 004 841129 1418 4.0 6.7 55 77 3.0 6.6 52 119 005 841129 1418 2.5 6.8 53 5 2.5 6.6 51 7 ""1"'1 006 841129 1418 3.5 &.1 49 139 2.5 &.9 53 107 II 007 841129 1418 2.5 6.6 52 160 3.5 6.1 49 100 008 841129 1418 3.1 7.6 60 72 1.8 6.5 50'--56 009 841129 1418 2.8 7.6 60 69 0.5 7.6 50 94 010 841129 1418 2.7 7.6 59 12 0.8 7.3 54 9 011 841129 1418 012 841129 1418 0.1 7.7 52 53 013 841129 1418 0.1 7.2 52 57 014 841129 1418 0.1 7.2 52 63 015 841129 1418 0.1 8.9 64 93 001 850108 1420 2.0 10.4 80 6.7 68 002 850108 1420 4.0 10.4 87 8.1 63 3.7 9.6 77 8.1 64 003 850108 1420 2.0 9.2 71 7.4 89 0.1 11.9 87 6.7 80 004 850108 1420 3.2 9.8 80 7.7 65 2.1 10.9 84 7.8 80 005 850108 1420 2.8 9.8 77 6.8 89 1.9 10.6 81 6.8 89 006 850108 1420 3.0 8.4 67 6.7 124 2.1 11.2 81 6.6 80 007 850108 1420 2.5 10.4 81 6.7 84 2.5 11.(,91 6.8 67 008 850108 1420 2.1 10.4 81 71 0.5 10.8 79 55 009 850108 1420 2.5 10.0 78 68 0.5 10.6 79 62 010 850108 1420 1.5 10.9 85 (,9 0.8 11.8 88 74 011 850108 1420 1.9 12.0 92 68 012 850]08 1420 013 850108 1420 014 850108 1420 2.2 9.7 76 57 1.8 10.4 80 63 015 850108 1420 001 850130 1300 002 850130 1300 3.5 9.1 73 6.7 76 3.3 8.8 71 7.0 68 003 850130 1300 2.1 9.5 7J 6.9 98 2.2 9.9 77 6.9 89 004 850130 1300 3.2 8.8 70 7.2 72 2.0 10.4 80 7.2 98 005 850130 1300 2.5 8.7 69 7.6 114 2.0 10.5 SO 7.1 98 006 850lJO 1300 3.1 7.6 60 7.1 129 2.1 10.5 81 7.2 107 007 850130 1300 2.5 9.3 73 7.1 102 1.4 10.9 82 7.2 95 008 850130 1300 2.8 9.3 74 7.1 61 0.9 10.4 77 7.1 83 009 850130 1300 2.8 9.4 74 7.J 69 1.2 10.5 79 7.3 55 010 850130 1300 2.6 9.4 70 7.4 70 l.0 10.:76 7.5 74 --------------------------------------------------------------------------------------------------------------------- fIT(I E-2 ,,"ppendix Table £-1.<Continued)• ""'"------------------------------------------------------------------------------------------------------------ Intragrave 1.Water Surface Water ------------------------------------------------------------------------ S4IlIpling DO DO Site Standpipe -------T_p.----------Conductivity Temp.-----------Conduct i.v:.:.y (River mil e)No.D"te time (C)(mg/O ISat.pH (umhos/em)(C)(mg/O ISat.pH (uchos rcc ': (y/m/d) ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------I 5ushrod Slough 011 850130 1300 3.0 9.6 76 7.4 72 2.2 11.2 86 7.4 71 (coot inued)012 850130 1300 013 850130 1300 014 850130 1300 2.2 8.6 62 7.1 53 1.0 9.4 70 7.4 74 015 850130 1300 ~ Curry Slougb 001 841128 1300 0.8 11.8 87 54 (119.7R)002 841128 1300 0.9 11.8 87 56 003 841128 1300 0.5 12.9 94 56 004 841128 1300 0.1 12.4 89 130 _;0; 005 841128 1300 1.2 7.4 55 92 2.1 11.5 88 62 006 841128 1300 0.1 14.8 108 171> 007 841128 1300 2.2 3.6 28 80 2.8 11.7 91 61 008 841128 1300 009 841128 1300 2.2 0.3 6 133 2.2 11.8 90 53 010 841128 1300 2.5 12.4 95 61 all 841128 1300 2.5 12.0 92 61 2.0 11.3 86 71 012 841128 1300 3.8 6.4 52 82 3.5 10.8 86 51 013 841128 1300 3.6 11.0 88 64 4.0 12.3 100 58 011>81>1128 1300 4.1 11.7 94 63 4.5 11.6 95 53 015 841128 1300 2.8 7.5 58 61 3.0 12.6 98 53 001 850109 1.3 8.3 63 6.5 77 1.3 12.0 89 6.6 58 002 850109 1.5 7.3 55 69 1.3 12.0 89 58 003 850109 004 850109 1.7 9.3 71 59 1.2 10.2 76 59 ""'"005 850109 006 850109 007 850109 2.2 2.3 18 92 2.0 10.4 79 57 008 850109 1.5 7.6 58 42 0.2 9.2 67 53 009 850109 1.6 0.7 8 112 1.0 8.8 65 41 -010 850109 011 850109 3.0 9.3 74 55 1.5 11.0 82 58 012 850109 3.5 8.8 71 54 2.0 10.3 80 so 013 850109 3.3 8.7 71 61 2.8 10.4 81 56 014 850109 3.9 9.8 79 62 4.0 10.5 85 so 015 850109 3.2 5.7 46 55 1.5 11.2 83 56 ~ 001 850129 1530 1 ..2 14.2 104 5.0 64 1.2 13.8 lOl 5.0 64 002 850129 1530 1.1 14.3 106 5.1 74 1.2 13.7 100 5.1 5~ 003 850129 1530 004 850129 1530 o.~12.9·95 5.0 56 O.l 12.5 89 5.0 -. 005 850129 1530 2~1 3.2 6 4.9 89 1.5 11.2 84 5.0 64 ~ 006 850129 1530 007 850129 1530 ',1.3 12 5.0 89 2.2 11.6 88 5.0 31 008 850129 1530 C.9 10.6 78 5.0 41 0.5 11.5 83 6.8 -. -------------------------------------------------------------------------------------------------_.If.II!IP! E-3 Appendix Table E-1.(Continued)• -------------------------------------------------------------------------------------------------------------------- lntragravel Water Surface Water ------------------------------------------------------------------------ Sampling DO 00 Site Standpipe ------------Temp.----_._----Conduct.ivity Temp.-----------Conductivity (River mile)!io.Date Time (C)(mgll)%Sat.pH (umhos/cm)(C)(mg/l):Sat.pH (umhos/cm) (y/m/d) -----------------------------------------------------------_._-----------------------------------~--------------------------------------------------------------------------------------------------------------------------------------- Curry Slough 009 850119 1530 1.8 2.&&.1 75 0.8 10.9 80 5.3 56 (continued)010 850129 1530 Oll 850129 1530 2.1 10.1 77 &.7 53 1.4 11.9 88 6.7 55 Oll 850129 1530 3.5 9.5 7&6.6 51 2.3 10.6 83 &.9 53 013 850129 1530 3.0 10.3 80 &.8 52 3.1 11.9 93 &.&48 014 850129 1530 4.0 10.4 83 &.7 58 3.1 11.9 93 &.6 52 015 850129 1530 2.1 11.7 89 6.2 53 2.1 12.6 95 &.3 46 Slougb 10 001 841114 1436 033.8L)002 841114 1436 003 -841114 1436 004 841114 1436 005 841114 1436 006 841114 1436 007 841114 1436 --, 008 841114 1436 009 841114 1436 010 1141114 1436 011 841114 1436 012 841114 1436 2.5 7.5 59 56 013 841114 1436 1.9 7.8 60 104 1.9 7.6 59 6.4 93 014 841114 1436 2.9 5.8 47 6.1 85 3.1 6.3 51 5.9 101 015 r84U14 1436 3.1 &.0 48 5.4 103 2.0 7.0 59 5.8 98 001 841127 1216 2.0 0.6 7 230 L8 12.0 92 162 002 841127 1216 1.5 0.8 9 165 L8 12.0 92 153 003 841127 1216 3.0 7.5 60 179 1.5 12.5 95 185 004 841127 1216 1.2 9.0 &8 169 1.8 12.4 94 1&2 005 841127 1216 1.2 9.4 71 138 l.5 12.2 94 172 006 841127 1216 1.8 1.0 11 183 2.0 11.7 90 143 007 841127 1216 2.1 6.2 48 158 1.8 10.5 81 142 008 841127 1216 2.0 4.6 36 169 2.2 11.0 86 142 009 841127 1216 2.2 0.6 9 181 2.2 10.5 82 138 010 84H27 1216 2.5 0.3 8 179 2.5 10.4 82 149 011 841127 1216 3.0 8.7 63 122 2.2 11.0 86 122 012 841127 121&3.2 8.1 65 134 2.5 8.8 70 123 013 841127 1216 2.1 9.1 71 121 2.8 9.8 77 123 014 84H27 1216 3.5 &.9 56 85 2.5 7.3 58 119 015 841127 1216 3.0 7.0 56 107 2.0 8.3 &4 134 001 841211 1300 1.1 1.3 11 230 LO 9.0 68 1&2 002 841211 1300 1.4 1.3 11 182 1.1 8.&65 156 -------------------------------------------------------------------------------------------------------------------- E-4 ~ Appendix Table E-1.(Continued). --------------~----------------------------------------------------------------------------------------------------- Intragravel Water Surface !,later ------------------------------------------------------------------------- Sampling DO DO Site Standpipe ---------Temp.------------Conductivity Temp.------------Conduc:::.iv tt)" (River mile)No.Date Time (C)(mg/Ll %Sat.pH (umhos/em)(C)(mgll)tSat.pH (umho.!em) (y/m/d)Ilm;!'~ --------------------------------------------------------------------------------------------------------------------- ----------------------------------------------------------------------~---------------------------------------------- 510ugb 10 003 841211 1300 1.0 10.2 77 199 -(eont inued)004 841211 1300 1.1 9.8 74 193 005 841211 1300 1.8 6.7 52 180 1.1 8.6 65 184 006 841211 1300 1.9 1.2 11 188 1.3 8.1 62 146 007 841211 1300 1.9 5.6 44 158 1.5 8.1 62 178 008 841211 1300 2.0 4.4 35 205 1.9 7.8 60 170 009 841211 1300 2.1 2.5 20 169 2.0 8.5 66 196 010 841211 1300 2.1 0.6 7 174 2.1 7.7 60 165 011 841211 1300 1.9 10.5 80 147 012 841211 1300 2.9 6.7 53 130 2.3 7.3 58 106 013 841211 1300 3.1 7.1 57 115 2.4 7.5 59 120 014 841211 1300 3.2 5.8 47 94 2.1 6.2 49 108 -015 841211 1300 2.9 5.8 46 100 2.0 7.1 56 87 001 850110 1300 2.2 1.1 8 7.2 158 2.5 8.5 67 7.0 137 002 850110 1300 2.0 0.5 7 169 2.5 8.6 67 6.1 139 003 850110 1300 2.8 6.2 49 155 2.2 9.2 72 163 004 850110 1300 2.5 6.6 52 154 2.0 8.6 67 164 005 850110 1300 2.9 6.9 55 173 2.0 8.7 67 166 006 850110 1300 2.8 0.7 9 171 2.8 8.6 69 139 007 850110 1300 2.8 5.3 42 160 2.8 8.3 66 135 008 850110 1300 2.5 5.4 43 161 2.8 8.1 65 137 009 850110 1300 2.9 0.4 7 142 2.9 7.8 62 133 ~ OlD 850110 1300 2.8 0.3 6 151 2.8 7.8 62 128 011 850110 1300 3.0 6.3 50 150 2.8 8.2 71 122 012 850110 1300 3.0 6.2 49 138 3.0 6.8 55 121 013 850110 1300 3.2 6.9 56 134 2.8 7.8 67 134 014 850110 1300 2.8 5.7 45 104 2.8 6.0 48 125 015 850110 1300 2.0 5.7 45 119 2.5 7.0 55 133 001 850201 1130 2.2 1.4 13 6.9 221 1.8 10.2 78 6.8 162 002 850201 1DO 2.2 1.2 12 7.1 213 2.0 9.8 76 7.1 161 003 850201 1130 2.8 6.6 53 7.5 174 1.8 10.7 82 7.5 189 004 850201 1130 1.8 6.7 52 7.4 183 1.8 10.2 80 7.5 180 ~005 850201 1130 1.6 11.1 85 7.4 181 006 850201 1130 2.0 1.2 11 7.2 143 2.0 10.0 78 7.5 143 007 850201 1130 2.5 6.1 48 7.2 193 2.0 9.6 75 7.3 143 008 850201 1130 2.2 7.4 58 7.3 174 1.8 9.6 74 7.3 144 009 850201 1130 2.2 0.5 8 7.4 195 2.1 8.9 70 7.3 151 010 850201 1130 2.4 0.6 8 7.2 194 2.2 8.8 70 7.4 151 -011 850201 1130 2.5 7.4 58 7.2 114 2.0 9.5 74 7.3 143 01:850201 1130 2.2 7.0 55 7.0 142 2.2 8.1 64 7.2 124 -------------------------------------------------------------------------------------------------------------------- E-S Appendix Table E-1.(Conrinued)• ------------------------------------------------------~------------------------------------------------------------ Ictragravel Va te r Surface Water ----~----------------------------------------------------------------- S_plillg DO DO Site Stalldp ipe ------Temp.--------Conductivit.y Temp.------------Conductivity (River mile)No.Dare Ti..,(C)(..gIll ISar.pH (umhoa/t..l (cl (",g/U ISar.pH (UlDhos/cm) (ria/d) ------------------------------------------------------------------------------------------~--~----------------------------------------------------------------------------------------~------------------------- IT'"Slaugh 10 013 850201 1130 2.8 7.9 63 6.8 130 2.8 9.1 72 6.9 156 I (cant inued)014 850201 1130 2.6 6.5 52 6.8 126 2.0 7.1 55 6.9 139 015 850201 1130 2.8 6.6 53 6.7 130 2.0 7.4 58 6.8 143 001 850402 1240 2.0 1.3 11 7.6 116 3.0 9.0 72 7.7 95 002 850402 1240 2.0 1.4 12 7.5 III 2.8 9.2 73 7.6 90 003 850402 1240 2.5 6.3 50 7.5 105 2.0 9.9 73 7.5 98 004 850402 1240 1.3 7.5 57 1.6 106 1.8 9.8 71 7.6 117 005 850402 1240 2.6 6.2 50 7.6 154 2.1 8.6 68 7.6 151 006 850402 12-40 3.2 8.9 72 1.6 129 007 850402 1240 2.5 9.6 76 7.5 158 3.1 8.8 71 7.6 124 ·008 850402 1240 2.2 6.3 50 7.6 124 3.1 8.1 65 7.7 125 009 850402 1240 2.5 1.2 11 7.8 132 4.2 7.8 65 7.8 124 010 850402 1240 2.5 0.6 10·7.5 114 3.0 7.7 62 7.8 117 011 850402 1240 2.6 6.8 54 7.4 119 3.1 8.7 70 7.5 103 r 012 850402 1240 2.9 5.9 47 7.6 112 2.8 7.9 63 7.6 104 013 850402 1240 2.9 6.8 54 7.4 107 2.5 7.6 61 7.5 114 'I 014 850402 1240 2.8 5.8 47 7.3 96 2.6 6.4 52 7.4 101 015 850402 1240 2.5 5.3 42 7.3 102 2.0 7.9 62 7.4 98 -------------------- -E-6 APPENDIX F FREEZE CORE SUBSTRATE DATA. F-l 1 --~1 ~1 Appendi.Tabl.f-l.Sub.trate compo.ition of .a.p1 ••collected uaing a freeze core .a.pl.r at three ••I.cted .Inugh.: March 1985 to April 1985,Suaitn.River,A1a.ka. ------------------~----------------------------------.---------~-----------------_.-----------------------.-------------------Subotrate .h.cl .....· (....) -----------------------------------------------------.----~-------------------------------------- 1 Total I >127 I 127-76.2 I 76.2-25.41 25.4-2.9 I 2.0-0.84 I 0.84-0,5 I 0.5-0.0621 <0.062 i------------------------------------------------------------------------------------------------- S....pllng I Dry I Dry I Dry I Dry I Dry I Dry I Dry 1 Dry I Dry Site Dote I wt.I wt.%1 wt.%I wt.%I lit.%I wt.%I lit.%I wt.%Iwt.%I (Riv.r mUe)Area (y/m/d)I (a)I (I)Tot.1 (a)Tot.1 (a)TOLl (g)Tot.1 (g)Tot.1 (a)Tot.1 (a)Tot.1 (a)Tot.1 ---------------------------------------.--------------------------------_._----------~-----------------------~---------------------------------------------------------------------------------------------------------------------------------------------- 8USHROD SLOUCH IA 850410 10300 0 0 4055 39 4886 47 530 5 262 3 92 1 387 4 88 1 (111.9L)U 850410 12522 3959 12 3351 27 2147 17 2242 18 253 2 13 1 {tIS 3 62 1 3A 850410 5555 0 0 0 0 2207 40 2363 43 319 6 84 2 498 9 84 2 4A 850410 2460 0 0 0 0 334 14 1123 46 109 4 60 2 743 30 91 4 SA 850410 9382 0 0 3626 39 3598 38 1525 16 223 2 104 1 238 3 68 1 18 850410 9371 0 0 3284 35 2929 31 .2217 24 250 3 134 1 443 5 114 1 28 850410 4308 0 0 0 0 933 22 1321 31 164 4 237 6 1550 36 103 1 38 850410 4033 0 0 0 0 2221 55 1315 34 205 5 49 1 152 4 11 1 48 850410 3095 0 0 0 0 219 9 2282 74 213 7 118 4 184 6 ,19 1 ."58 850410 10921 0 0 5823 53 3124 29 1364 12 200 2 128 1 253 2 29 0 I N CURIlY SLOUCH lA 850328 9926 0 0 2974 30 3199 )8 1805 18 148 1 53 1 710 7 437 4 (l19.7R)5...850328 2213 0 0 1287 57 169 7 70 3 4 0 2 0 456 20 285 13 la 850326 9355 0 0 3813 41 2856 31 1769 19 161 2 171 2 511 6 68 1 58 850328 2775 0 0 0 0 1432 52 846 30 48 2 14 1 350 13 85 3 SLOUCR 10 1A 850327 449 0 0 0 0 0 0 1 0 2 0 5 1 213 47 228 51 (13l-8L)2A 850327 2J4 0 0 0 0 0 0 0 0 0 0 1 0 105 49 108 50 301.850327 598 0 0 0 0 0 0 2 0 5 1 26 4 510 85 H 9 4A 850327 367 0 0 0 0 0 0 16 4 2 1 5 1 242 66 102 28 SA 850327 1689 6750 88 0 0 359 5 446 6 30 0 15 0 89 1 0 0 11 850327 114 0 0 0 0 0 0 0 0 1 1 0 0 34 30 79 69 . 2B 650327 42 0 0 0 0 0 0 8 19 2 5 1 2 13 31 18 43 )1 850327 158 0 0 0 0 0 0 5 )1 1 2 1 82 52 68 43 48 850327 156 0 0 0 0 0 0 1 A 1 1 3 2 87 56 62 40 58 850327 859 0 0 0 0 306 36 351 42 61 7 28 3 98 11 9 J ------------------------------------------------------------------------------------------------------------------------------