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AEA Susitna Water Quality and Sediment Transport Data Gap Analysis Report July 26, 2011
AEA Susitna Water Quality and Sediment Transport Data Gap Analysis Report July 26,2011 Arctic HydrologicTtTETRATECHConsultants WATANA HYDRO PROJECT:WATER QUALITY AND SEDIMENT DATA GAP ANALYSIS TABLE OF CONTENTS EXCCUtIVE SUMMALY.....c.ccccessscccnveccrnescccccnccseenoneeseccoeseescnecouscanescoesananscensesesanescecanareescaeesseseneescsssoeeoees 1 1 INtrOMUCTION 00...secscrecesecsscceccsccceeccenscecsssscceecsnscsesscssecccsessesseassscsnseaeccsnsasessencecsssescessosnconeeasens 3 2 Background sesesccecccccccouaeaacaaeeeeeeeeeeeseseesessessseoeeseseeeesseeeeceeeeeeOseseanaaaauanesoeoececccccsessssscsssseceeeee 3 2.1 Site D@SCIIPLION ......ee eee eeeceseeeeensscesessesescececeneesoeeessccucesesceeensatecssceceseesesseresesescseesenedeesneeseneesase 3 2.2 Project HiStOLY 0...ceccccenncsceesseessssesssesnssenecsscassseasecsssnecssescegasseseseccesscssssensasessuseseusssseesersesesuteess 6 3 Methodology for Analyzing Potential Data Gaps..........cssssssssssssssssssssssssccsssesssscssssssenscsccsssneesseeaes 6 A ---Water QUuallity..........cccsssssssscoeseccccesccsssesssssessnenseassonsscaneacassssecesccassaccnsseceesececcsacesseeesssccccceseccsceeseses 9 4.1 Summary of Data RECOVErEd ...........eeccesscestcetsreesnecterenceesnerssseneasseenssensstsssecssesesessssesseseseasssoneees 10 4.2 Data Quality .......i eccsececereesstcesstossesenecenanesssseeesenascecasescceessosesscceseceecesesesscssesonoeessssesensesereesecsees 20 4.3 Applicable Water Quality Standards ............ecsccsssessscesseeeseesecesscesenersntssstcsncesseesdseseseesesseasaseeeas 20 4.4 Locations Exceeding Water Quality Standards .......ee ceccscccseesscetseeesececeneceressaesenensoeseoesensoneas 23 4.5 -Timing of Pollutant Introduction...cessssscececseessceesoeecseecenessoeseceseoeecanecaeecanscaustnesenessersssaseese 30 4.6 Distribution of Primary Fish Species in the Susitna Drainage ........cccssecscseeseeceaseesesesseeesesevees 34 4.7 Influence of Pollutants On Fish SpeCieS.........cccsscssccsscssececsescseccescescetsoeesenecceeceeeceneesaesenssnressaaseess 37 4.8 Data Gaps and Need for Additional Information.............eecscssssssscssccsesssersecesssessescsssesnesseesssessens 40 4.9 Potential Influence of the Project on Water Quality Conditions ..........ccsssessesssessecsessssensonees 43 4.10 Long-term Monitoring Concepts.........ccsccsescssseecessssccsseenssseeesssesoneessssersessecesnsscoesssanaseseseeesseresses 44 5 -_Sediment Transport..........sccccccsssssssscsccecccesssssccccccssesscvsvscssccnsssessssnsacaccnccsssssuscsessssecessecensanenssoees 45 5.1 Considerations Upstream of Watana Dam...eessstesssssscseeseseseecessesessnssoseeasseasassaseneeserens 46 5.1.1 Sedimentation where the Susitna River enters Watana RESErvOIr .........ssssscseeeseeseseees 46 5.1.2 Watana Reservoir Shoreline Erosion «0.0...scscssssssssssssssecsccsscsssesessssssssresesssssesscstessenseesses 47 5.1.3 Sedimentation at Tributary MOUthS............cc ccsssceseeceeeeeeesseececceeessusassssesoseesveseesenenssenseaseees 47 5.2 Considerations Downstream Of Watana Dam ........ccssccssscsssesssesssestssssecensesssessessersenscenssseeensseees 47 5.2.1 Regulated Hydrology...........csscescssessssssessessessssessssssscesssssenecseserenesaesecsacseesssensseseeereneseetaseeees 48 5.2.2 Sediment Continuity ...........sccceccesesccseessessseessussesscscessssssasescseesseonepesseseessesaesessesssenesnseasneeesees 50 5.2.3 Analysis of Sediment Transport Data Gaps........cccssssssssssssrsssseeeessssssaseensesenenesensesseeaeees 51 6G -REFEEMCES .......ccccssccccsscnssrcccesrsssesscnnceesssccscesescacsensscsosssessscasccsessseeesenansunsecsssessnasesoesescusesaaaaeoooes 53 bi RFP#2011-006 |URS |Tetra Tech,Inc.|Arctic Hydrology | WATANA HYDRO PROJECT:WATER QUALITY AND SEDIMENT DATA GAP ANALYSIS I vr ie! LIST OF TABLES Table 3-1.Segmentation scheme for the Susitna River Basin (APA 1983)............:csssesscsecessteneesseeeseeeeeees 8 Table 3-2.Reach segmentation for the Susitna River Basin data gap analySis...........sccsscsssessceerecessesseeeseees 9 Table 4-1.Data Resources Used to Create Water Quality Data Summary Tables (Appendix B)...........0 12 Table 4-2.Additional Documents Reviewed from Reference Library on AEA Sharepoint Site..............008 15 Table 4-3.Documents of Interest (Possible Water Quality Data Source)But Not Available Electronically ON AEA Sharepoint Site.00...eecessccsresstenstenssncssccsececsesssesseeeeseeseseesecseesscesssseenscesesescssseesassessssesesceuusessaess 18 Table 4-4.Alaska State Water Quality Standards for the Protection of Aquatic Life and Wildlife (18 AAC 70,May 2011)....c.cccccscccscsssersssscsescccsssessssesseccsessessecssnsseensssessecsecsnssssssessusassssssssesseecarssersscesesereersensneseneens 21 Table 4-5.Alaska State Water Quality Standards for Toxics and Other Deleterious Organic and Inorganic Substances (December 2008)..........:.sscccsssssccssscsssccsscesscesseesseesseeeseeesececceseaeessenssdessscseesecessaesseeeeedsessaseasecess 22 Table 4-6.2008 Susitna River Basin Temperatures (Cook Inlet Keepers,via personal communication)...25 Table 4-7.2009 Susitna River Basin Temperatures (Cook Inlet Keepers,via personal communication)..26 Table 4-8.Location of continuous temperature monitoring data on tributaries of the Susitna River mainstem (Cook Inlet Keeper,2008 and 2009).0.0...cecessesescsssscssesesessesessessseseeceesosesenscsecssusssesssessessesneees 28 Table 4-9.Location of water quality criteria exceedances in the Susitna River drainage...........ssssecseees 29 Table 4-10.Presence of fish species by Susitna River reach and SegMent.........sccsscssccccscssesssesesesresessesees 32 Table 4-11.Fish populations and life stage uses in Susitna River reaches........scsescsscescessssssesesseseenseres 35 Table 4-12.Available toxics threshold concentrations that effect select fish species known to occur in the Susitna River drainage...........ccsssccsscsscesssesreseessssssssecedeosesseeseessassnessssssssessssscssesessesesscaseseeesessessaeeseesnentes 38 Table 4-13.Location of water quality conditions that present potential bioaccumulation of toxics in fish species in the Susitna River drainage........ssssssssssesssecessesssssssssseesscssssssessessscseenesseneenenetsntstatsssessasesesontes 39 Table 4-14.Reach segmentation for the Susitna River Basin data gap analySis...........ssssseseesereeestereees 40 LIST OF FIGURES Figure 2-1.Susitna River Drainage Basin (MWH 2011).........cccsesseseressesseesessececesensseteneeetieseeecesesessensnennes 5 Figure 4-1.Mat-Su temperature monitoring locations,corresponding watersheds are highlighted.......29 Figure 5-1.Average annual flow distribution for the Susitna River (MWH 2011)........ssssssessssesseeseessees 49 APPENDICES APPENDIX A:BIBLIOGRAPHY OF REFERENCE LITERATURE APPENDIX B:WATER QUALITY DATA SUMMARIES FROM EXISTING SOURCES Bik ;RFP#2011-006 |URS |Tetra Tech,Inc.|Arctic Hydrology | SUSITNA-WATANA HYDRO PROJECT:WATER QUALITY AND SEDIMENT DATA GAP |geANALYSIS Executive Summary A review of available data describing water quality conditions and sediment transport in the Susitna River drainage,and identification of significant data gaps,represents one of the initial steps for development of the Watana Hydro Project.Technical documents generated over the past 30 years were reviewed for water quality and sediment transport data on conditions in the drainage,and identified physical locations and time periods where data was not available.Data were examined to determine current water quality and sediment transport conditions and how these characteristics currently influence anadromous fisheries throughout the drainage.Establishment of the Susitna-Watana Project on the mainstem Susitna River will require an evaluation of current river hydrology and water quality in support of the FERC license application.Data gaps in the available data were identified to inform the next phases of the hydro development project. In general,water quality conditions in the Susitna River and tributaries had elevated metals concentrations that periodically exceeded toxic thresholds for salmon and rainbow trout.The moderate water hardness at mainstem and some tributary locations will ameliorate toxic effects of some of the metals if in contact with aquatic life.Nutrient concentrations (e.g.,nitrates and phosphates)were generally low throughout the drainage,except for select tributary locations during the fall season where nitrogen increases correspond with increasing presence of salmon carcasses.Most tributaries exceeded spawning water temperature criteria and the maintstem Susitna exceeded water temperature criteria for migration. Although observations for metals in select areas of the Susitna River drainage were acknowledged as having a high background concentration,the sources for these metals and the potential for release following establishment of the project could increase the risk of mortality in select fish populations. Aluminum,copper,and iron concentrations in surface water throughout the areas where data were available exceeded toxics thresholds that indicate chronic problems in select populations were likely. Surface water criteria indicated that aluminum concentrations were consistently high throughout the drainage and that temperature conditions were especially high in tributaries,exceeding criteria for salmonid spawning and migration.Water quality conditions in this drainage enable fisheries to locate and reside in refugia suitable for survival of several life stages.A more dense sampling effort would be required throughout the drainage to describe how pre-project and post-project physicochemical conditions would influence existing fisheries populations in the Susitna River and tributaries.Most of the available data was almost 30 years old and did not have the spatial coverage necessary for a more comprehensive evaluation of water quality conditions.A general comment about existing data is that it does not generally represent present conditions and more current information will be necessary to construct reliable predictions about impact to critical habitats of salmon and steelhead populations in the mainstem Susitna River and at the mouths of tributaries throughout the downstream project area. The sediment transport analysis of existing data was approached by partitioning the drainage into two parts;sediment transport would differentially be influenced by reservoir dynamics above the proposed ak -@ RFP#2011-006 |URS |Tetra Tech,Inc.|Arctic Hydrology | vg SUSITNA-WATANA HYDRO PROJECT:WATER QUALITY AND SEDIMENT DATA GAP i me oe :ANALYSIS uly 26,2011 hydro project and below this point in a regulated river channel.Sediment transport data examined from the Susitna River drainage reflected conditions that were almost 30 years old.Review of this data limited analysis based on age and lack of points for calibration with current investigations.Predictions for changes to sediment transport in the Susitna River require that a current and comprehensive baseline of information be developed and this was not possible to complete with existing data in the lower Susitna River.Once this anchor is established describing current sediment transport conditions, generation of post-project conditions can be made.Examination of available sediment discharge rating curves predicts delta formation at the head of the newly formed reservoir as well as mouths of downstream tributaries.Water level in the regulated portion of the river will determine if important tributaries become impassable barriers to migrating fish populations.Sediment transport from the Chulitna and Talkeetna Rivers is three times as large as from the mainstem Susitna River;these tributaries may have a greater influence on habitat formation and maintenance for salmon populations. Sediment transport dynamics has an integral role in maintaining habitat connectivity for anadromous fish populations.Stage-discharge relations that are governed by both reach-scale and local aggradation and degradation as well as the magnitude of the flow are important for maintaining critical side channel and slough habitats.Project impacts are thus most likely to occur between the mouth of Devil's Canyon and the confluences with the Chulitna and Talkeetna Rivers and immediately downstream of the confluences. RFP#2011-006 |URS |Tetra Tech,Inc.|Arctic Hydrology | SUSITNA-WATANA HYDRO PROJECT:WATER QUALITY AND SEDIMENT DATA GAP ANALYSIS 1 Introduction This report documents existing information on water quality and sediment in the Susitna River basin with emphasis on the Susitna-Watana Hydroelectric Project (Project)area and downstream reaches. The purpose of this data gap analysis is to evaluate available information for its relevance and applicability to the proposed Project for the Alaska Energy Authority (AEA),and help with the National Environmental Policy Act (NEPA)scoping and study planning activities conducted as part of the Federal Energy Regulatory Commission (FERC)licensing process.This document focuses on potential data gaps identified for the following resources that may be impacted by the proposed Project: e Water quality o Conventional and metals parameters o Anadromous and resident fisheries o Analysis of toxics e Sediment transport o Hydrology o Sediment supply,transport,and deposition/sedimentation o Stage-discharge relations in the aquatic habitat reaches o Formation and adjustment of dynamic aquatic habitats Information needs resulting,in part,from the data gap analyses,will be refined when an updated description of Project facilities,operations,and construction activities is developed.The data reviewed for this analysis are contained in selected documents developed as part of the original Susitna Project licensing effort in the early 1980s,along with more recent,readily available reports.These documents are summarized in Section 4 of this report. 2 Background An overview of the proposed Project site and the history of the Project are provided as context for the data gap analysis. 2.1 Site Description The proposed Susinta-Watana Project on the Susitna River is located in the south-central region of Alaska (Figure 2-1),approximately 118 miles north of Anchorage.This region is bounded by the Alaska Range to the north and west,the Wrangell Mountains to the east,and the Chugach Mountains and the Gulf of Alaska to the south.The 19,400 square mile Susitna River basin is bordered by the Alaska Range to the north,the Chulitna and Talkeetna Mountains to the west and south,and the northern Talkeetna plateau and Gulkana uplands to the east.Major tributaries to the Susitna River include the McLaren River,the Chulitna River,the Talkeetna River,and the Yentna River.The Project site is situated at Susitna River Mile (RM)184,as measured upstream from the mouth of the Susitna River.In the vicinity of the proposed impoundment,the river has cut a narrow,steep-walled gorge up to 1,000 feet deep. €4}RFP#2011-006 |URS |Tetra Tech,Inc.|Arctic Hydrology | SUSITNA-WATANA HYDRO PROJECT:WATER QUALITY AND SEDIMENT DATA GAP ANALYSIS The Susitna River is typical of unregulated northern glacial rivers with high,turbid summer flow and low, clear winter flow.Due to runoff from snowmelt and rainfall in the spring,approximately 80 percent of the annual flow occurs between May and September.As weather begins to cool in the fall,freeze up normally begins in October and continues to progress through early December;breakup generally begins in late April or early May near the mouth and progresses upstream with breakup at the proposed Project occurring in mid-May. Fish resources in the Susitna River comprise a major portion of the Cook Inlet commercial salmon harvest and provide sport fishing for Anchorage,Matanuska-Susitna Borough and other areas of the State.The Susitna River is a migration corridor,spawning area,and juvenile rearing areas for five species of salmon (i.e.,pink,chum,coho,sockeye,and chinook)mostly distributed from its mouth to the mouth of Devil's Canyon,a natural barrier due to water velocity at high flows;however there have been recent findings of some juvenile salmonids above Devil's Canyon.In addition to salmon,the Susitna River watershed also supports grayling,trout,whitefish,burbot,and other species important to sport fisheries 2)j RFP#2011-006 |URS |Tetra Tech,Inc.|Arctic Hydrology | WATANA HYDRO PROJECT:WATER QUALITY AND SEDIMENT DATA GAP ANALYSIS I me!°"ee i Sf TY SevtensRivweatCalfidosen< eg foe BF ase Sata |epeepapremaeersaren Bf BI =er EXHIBIT 4 NNoTEs:SUSITNA RIVER DRAINAGE BASIN BOUNDARY ®MWH>%raphy"Ts0s NosnatElevation Dataset (NED).2-Arc Secomd AND3.Bown boundary beeed on modited USGS HUCs 19C20801-S STREAMFLOW GAGE LOCATIONS os cives Date:May 28,2011 Figure 2-1.Susitna River Drainage Basin (MWH 2011). |;i RFP#2011-006 |URS |Tetra Tech,Inc.|Arctic Hydrology | WATANA HYDRO PROJECT:WATER QUALITY AND SEDIMENT DATA GAP ANALYSIS e ee msemorn 2.2 Project History The Susitna River was identified as a potential large hydropower site in the 1940s by the Bureau of Reclamation.In a 1976 report to Congress,the U.S.Army Corps of Engineers (Corps)proposed a two- dam scheme capable of producing 7,300 Gigawatt hours (GWh)of hydropower (Harza Ebasco 1987). This concept was adopted by the Alaska Power Authority (APA,currently the AEA),which began managing the project in 1980,and contracted with Acres America to review economic and environmental feasibility and file a FERC license application.Later Harza-Ebasco was contracted to update the license application and perform final design.The 1980's APA Project consisted of two dams: the first located in Watana Canyon at approximately Susitna River Mile (RM)184 and a second located at the mouth of Devil's Canyon (referred to as the Devil's Canyon site in most earlier studies)(RM 152). The 1980s APA Project effort culminated in the development of a license application filed with FERC in 1983,and an amended license application prepared in 1985.The project was cancelled in early 1986 in the face of declining oil revenues.In support of the 1983 and 1985 FERC license applications,the APA conducted comprehensive baseline environmental studies throughout the basin,with the most extensive aquatic efforts focused on the middle stretch of the Susitna upstream of Talkeetna.A library of more than 3,500 reference documents was cataloged at the conclusion ofthe project (Harza-Ebasco 1987). The current Susitna-Watana Hydroelectric Project being evaluated by the AEA is located approximately half-way between Anchorage and Fairbanks.The proposed Project would create a single dam on the Susitna River at RM 184 in the vicinity of Watana Canyon.The approximately 700-foot-high dam would have an approximate 557-foot difference between the elevations of the tail water and the maximum pool (AEA 2010).Watana Reservoir would be 39 miles long and a maximum of 2 miles wide.The dam's installed capacity would be around 600 megawatts (MW)with the average annual generation estimated to be 2,600 GWh (AEA 2010).The AEA is currently studying design considerations in order to formulate decisions regarding the type of dam or powerhouse (underground or surface)that would be used as well as the actual final maximum reservoir level.At this time the actual operation characteristics of the Project are not known,but the current concept is that the Project would provide peaking operations using the reservoir storage to meet daily instream flow and power needs.The current Susitna Watana Project is thought to be a licensable project without a fatal flaw (AEA 2010). 3 Methodology for Analyzing Potential Data Gaps The licensing effort of the 1980's APA Project generated a substantial body of literature,some of which might be used to support future licensing.To evaluate potential Project impacts and to protect wildlife and their habitats,the 1980s study effort sought to describe baseline conditions at a level of reliability necessary to detect and explain possible future changes caused by the proposed hydroelectric development as it was configured at that time (ADF&G 1985a).Additional reports related to resources in the vicinity of the proposed Project have been published since the mid-1980s. li 3 RFP#2011-006 |URS |Tetra Tech,Inc.|Arctic Hydrology | WATANA HYDRO PROJECT:WATER QUALITY AND SEDIMENT DATA GAP ANALYSIS .toe ANE 6" The URS Team reviewed and synthesized data collected during the 1980s,along with more recent information from resource agencies.Information was compiled and made available for review through a URS FTP site and through an AEA SharePoint site.Not all of the older materials have been scanned,so the information on the SharePoint site was limited and only information posted by early July was available for review. Based on the available sources of information,the primary water quality and sediment transport issues related to the construction and operation of the Susitna-Watana Project are:1)water quality,with particular emphasis on the potential impacts to fish resources and changes to physicochemical habitat resulting from project operations,and 2)sediment transport,focusing on potential impacts to aquatic habitats and potential downstream flooding and channel stability.These issues were considered during the review of documents to identify gaps in data that would allow for meaningful comparisons of with and without project conditions. The Susitna River was divided into segments to provide a framework for organizing and interpreting available data.Discrete segments of the river are identifiable based on longitudinal changes reflected in physical features ofthe river channel.A river segmentation scheme was developed in earlier technical studies that evaluated information about the Susitna River drainage through 1983.The Application for Development of a Major Project prepared by Acres (1983)detailed how river segmentation was determined and provided a description for the distinct river segments.This segmentation scheme is presented in Table 3-1. RFP#2011-006 |URS |Tetra Tech,Inc.|Arctic Hydrology | WATANA HYDRO PROJECT:WATER QUALITY AND SEDIMENT DATA GAP ANALYSIS Table 3-1.Segmentation scheme for the Susitna River Basin (APA 1983a). Bounds of Segment Average Bed Slope . (Susitna River Miles)(feet/foot)*Predominant Channel Morphology 313-223 n/a Glacial and non-glacial headwaters,upper basin Approximate extent of proposed 223-184 n/a reservoir impounded by Watana Dam at RM 184 184-149 0.00337 Steep side canyon and Devil's Canyon 149-144 0.00195 Single channel confined by valley walls,frequent bedrock control points 144-139 0.00260 Split channel morphology confined by valley walls and terraces Well defined split channel morphology, 139 -129.5 0.00210 frequent side channels separated from main channel by vegetated islands Well defined split channel morphology, 129.5-119 0.00173 confined by valley walls,occasional bedrock control points Predominantly a single incised channel119-104 0.00153 with few islands Transition to braided channel morphology,terraces bound broad floodplain at confluence of Susitna, Chulitna,and Talkeetna Rivers 104-95 0.00147 Braided channel morphology,multiple 95-61 0.00105 channels,sparsely vegetated floodplain Multiple channel separated by61-42 0.00073 vegetated islands Split channel morphology,occasional braiding,distributary channel influenced by tidal fluctuations in Cook Inlet 42-0 0.00030 "Average bed slopes as presented in Table E.2.1 (APA 1983a) The segmentation scheme in Table 3-1 was initially considered for use during the data gap analyses; however,it became apparent that the resolution of the segments was too detailed given the limited available water quality and sediment transport data.A more appropriate delineation of reaches was developed specifically for use in the data gap analyses (Table 3-2). |RFP#2011-006 |URS |Tetra Tech,Inc.|Arctic Hydrology | wiice WATANA HYDRO PROJECT:WATER QUALITY AND SEDIMENT DATA GAP ANALYSIS Table 3-2.Reach segmentation for the Susitna River Basin data gap analysis. Bounds of Reach .::R ipti (Susitna River Miles)each Number General Description Upper Susitna River,including 313-184 1 headwaters and tributaries above the proposed Watana dam site Middle Susitna River and tributaries 184-150 2 through Devil's Canyon and below the proposed Watana Dam site Middle Susitna River and tributaries from the mouth of Devil's Canyon to the Susitna -Chulitna -Talkeetna confluence 150-99 3 Lower Susitna River from Susitna - 99-0 4 Chulitna -Talkeetna confluence to mouth at Cook Inlet Further details of methodologies specific to the hydrology,water quality,and sediment transport gap analyses are presented in Section 4 and Section 5. 4 Water Quality The water quality data gap analysis included several components that included review of collected data reports and finalized data sets that could suggest possible influences on future water quality conditions. Several steps were identified for this project that satisfied objectives and are summarized as follows: e Data Collection from Sources e Data Review for Quality and Summaries e Data Analysis/Interpretation e Identify Data Gaps e Predict Potential Project Impact Each of the steps addressed in the following sections relates known water quality conditions where rainbow trout,grayling,and several species of salmon are present.The tolerance of fish species to environmental contaminants is an important factor for evaluation of water quality conditions as these thresholds incorporate experimental and field survey results that determine toxic effects and potential for bioaccumulation. A standardized segmentation strategy was developed and used to describe locations where water quality information is found and conditions that may affect resident and anadromous fish populations. The water quality data gap analysis identified conditions in several reaches of the Susitna River drainage based on the reach descriptions in Table 3-2. RFP#2011-006 |URS |Tetra Tech,Inc.|Arctic Hydrology | WATANA HYDRO PROJECT:WATER QUALITY AND SEDIMENT DATA GAP ANALYSIS -fiuly 2072011) 4.1 Summary of Data Recovered The available existing information was collected and evaluated in terms of its potential relevance and completeness,and whether the methods used produced information that could be applicable to the anticipated environmental analysis for the proposed Project.Other sources of information used in the analysis included that derived from contacts with agency project leaders and database searches.If information was determined to be likely insufficient for satisfying environmental analysis requirements, a potential data gap was identified. A review of existing data generated by governmental agencies and organizations was used as background information to evaluate current and past water quality conditions in the Susitna River drainage.Natural resource agencies were identified and lead staff contacted for location of relevant information and web sites searched for general description of drainage conditions as well as for water quality data that could be further analyzed.The following agencies were initially identified for available information from the Susitna River drainage and contiguous areas: e Alaska Department of Environmental Conservation e Alaska Department of Fish and Game e Alaska Department of Natural Resources e U.S.Environmental Protection Agency,Region 10 e U.S.Fish and Wildlife Service e U.S.Geological Survey ¢National Oceanic and Atmospheric Administration-Fisheries e Alaska Energy Authority/Alaska Power Authority e¢American Geophysical Union Relevant documents were collected in electronic form and stored in an electronic bibliography for use in data review and summarization (Appendix A).Water quality data discovered in document review was either included in a spreadsheet and used in further analysis for data gap analysis or was summarized using numerical expressions including minimum value,average value,and maximum value recorded at a station in the Susitna River drainage including tributaries.Results from river and tributary stations were organized according to river mile location and aggregated into river segment categories. Existing data was organized along a longitudinal gradient (Headwaters to Mouth)so that data gaps in water quality information could be identified by visually examining the summary water quality tables (Appendix B).The origin of data entries in these summary water quality data tables were found in several documents listed in Tables 4-1 and Table 4-2.Table 4-1 lists data resources used to build the by RFP#2011-006 |URS |Tetra Tech,Inc.|Arctic Hydrology | WATANA HYDRO PROJECT:WATER QUALITY AND SEDIMENT DATA GAP ANALYSIS eg vs summary water quality data tables prior to complete access to the extensive reference library on the AEA SharePoint Site.Table 4-2 lists resources on the AEA SharePoint Site that were reviewed for additional water quality information.Table 4-3 is a collection of references that may include relevant water quality information but were not accessible during the review of existing information.Many of these remaining documents were not available in electronic form on the project SharePoint site,but were published during the same years as those reviewed.The same available data sets had been cited and used in multiple documents throughout this time period and did not offer new information for this data gap analysis.However,these resources could be collected at a later data and examined for relevant water quality information. bake j RFP#2011-006 |URS |Tetra Tech,Inc.|Arctic Hydrology | WATANA HYDRO PROJECT:WATER QUALITY AND SEDIMENT DATA GAP ANALYSIS :é ivaee| Table 4-1.Data Resources Used to Create Water Quality Data Summary Tables (Appendix B). DATE SOURCE AUTHOR TITLE LOCATION 1983 |Alaska Power Acres FERC Application for License University of Washington Library Authority for Major Project Susitna Hydroelectric Project,Vol.5, Exhibit E,Chapters 1&2 1986 |Alaska Power Harza-Ebasco Susitna Hydroelectric Project http://sharepoint.aidea.org/railbeltlargehydro/Reference% Authority Susitna Joint Water Quality Monitoring 1985 |20Library/Susitna%20Historical%20Documents/Pre%20200 Venture 0%20Documents/3402.pdf (AEA Reference Library) 1990 |United States USGS Largest Rivers in the United http://pubs.usgs.gov/of/1987/ofr87-242/ Geological Survey States 2008 |United States USGS Suspended Sediment Database |http://co.water.usgs.gov/sediment/conc.frame.html Geological Survey Daily Values of Suspended Sediment and Ancillary Data 1986 |United States USGS USGS 15291000 SUSITNAR NR_|http://nwis.waterdata.usgs.gov/nwis/qwdata?site_no=1529 Geological Survey DENALI AK 1000&agency_cd=USGS&inventory_output=0&rdb_invento ry_output=file&TZoutput=0&pm_cd_compare=Greaterthan &radio_parm_cds=all_parm_cds&format=html_table&qw_ attributes=O&qw_sample_wide=wide&rdb_qw_attributes= O&date_format=YYYY-MM- DD&rdb_compression=file&submitted_ form=brief_list 1975 |United States USGS USGS 15291200 MACLAREN R_|http://nwis.waterdata.usgs.gov/nwis/qwdata?site_no=1529 Geological Survey NR PAXSON AK 1200&agency_cd=USGS&inventory_output=O0&rdb_invento ry_output=file&TZoutput=0&pm_cd_compare=Greaterthan &radio_parm_cds=all_parm_cds&format=html_table&qw_ attributes=O&qw_sample_wide=wide&rdb_qw_attributes= O&date_format=YYYY-MM- DD&rdb_compression=file&submitted_ form=brief_list be RFP#2011-006 |URS |Tetra Tech,Inc.|Arctic Hydrology | WATANA HYDRO PROJECT:WATER QUALITY AND SEDIMENT DATA GAP ANALYSIS DATE SOURCE AUTHOR TITLE LOCATION 1986 United States Geological Survey USGS USGS 15291500 SUSITNA R NR CANTWELL AK http://nwis.waterdata.usgs.gov/nwis/qwdata?site_no=1529 1500&agency_cd=USGS&inventory_output=0&rdb_invento ry_output=file&TZoutput=0&pm_cd_compare=Greaterthan &radio_parm_cds=all_parm_cds&format=html_table&qw_ attributes=O&qw_sample_wide=wide&rdb_qw_attributes= O&date_format=YYYY-MM- DD&rdb_compression=file&submitted_ form=brief_list 1986 United States Geological Survey USGS USGS 15292000 SUSITNA R AT GOLD CREEK AK http://nwis.waterdata.usgs.gov/nwis/qwdata?site_no=1529 2000&agency_cd=USGS&inventory_output=0&rdb_invento ry_output=file&TZoutput=0&pm_cd_compare=Greaterthan &radio_parm_cds=all_parm_cds&format=html_table&qw_ attributes=O&qw_sample_wide=wide&rdb_qw_attributes= O&date_format=YYYY-MM- DD&rdb_compression=file&submitted_ form=brief_list 1986 United States Geological Survey USGS USGS 15292400 CHULITNA R NR TALKEETNA AK http://nwis.waterdata.usgs.gov/nwis/qwdata?site_no=1529 2400&agency_cd=USGS&inventory_output=0&rdb_invento ry_output=file&TZoutput=0&pm_cd_compare=Greaterthan &radio_parm_cds=all_parm_cds&format=html_table&qw_ attributes=O&qw_sample_wide=wide&rdb_qw_attributes= O&date_format=YYYY-MM- DD&rdb_compression=file&submitted_ form=brief_list bEitil RFP#2011-006 |URS |Tetra Tech,Inc.|Arctic Hydrology | WATANA HYDRO PROJECT:WATER QUALITY AND SEDIMENT DATA GAP ANALYSIS DATE SOURCE AUTHOR TITLE LOCATION 2011 United States Geological Survey USGS USGS 15292700 TALKEETNA R NR TALKEETNA AK http://nwis.waterdata.usgs.gov/nwis/qwdata?site_no=1529 2700&agency_cd=USGS&inventory_output=O0&rdb_invento ry_output=file&TZoutput=0&pm_cd_compare=Greaterthan &radio_parm_cds=all_parm_cds&format=html_table&qw_ attributes=-O&qw_sample_wide=wide&rdb_qw_attributes= O&date_format=YYYY-MM- DD&rdb_compression=file&submitted_ form=brief_list 1986 United States Geological Survey USGS USGS 15292780 SUSITNA R AT SUNSHINE AK http://nwis.waterdata.usgs.gov/nwis/qwdata?site_no=1529 2780&agency_cd=USGS&inventory_output=0&rdb_invento ry_output=file&TZoutput=0&pm_cd_compare=Greaterthan &radio_parm_cds=all_parm_cds&format=html_table&qw_ attributes=-O&qw_sample_wide=wide&rdb_qw_attributes= O&date_format=YYYY-MM- DD&rdb_compression=file&submitted_ form=brief_list 1981 United States Geological Survey USGS USGS 15294300 SKWENTNA R NR SKWENTNA AK http://nwis.waterdata.usgs.gov/nwis/qwdata?site_no=1529 4300&agency_cd=USGS&inventory_output=0&rdb_invento ry_output=file&TZoutput=0&pm_cd_compare=Greaterthan &radio_parm_cds=all_parm_cds&format=html_table&qw_ attributes=-0&qw_sample_wide=wide&rdb_qw_attributes= O&date_format=YYYY-MM- DD&rdb_compression=file&submitted_ form=brief_list 1986 United States Geological Survey USGS USGS 15294345 YENTNA R NR SUSITNA STATION AK http://nwis.waterdata.usgs.gov/nwis/qwdata?site_no=1529 4345&agency_cd=USGS&inventory_output=0&rdb_invento ry_output=file&TZoutput=0&pm_cd_compare=Greaterthan &radio_parm_cds=all_parm_cds&format=html_table&qw_ attributes-O&qw_sample_wide=wide&rdb_qw_attributes= O&date_format=YYYY-MM- DD&rdb_compression=file&submitted_ 2)RFP#2011-006 |URS |Tetra Tech,Inc.|Arctic Hydrology | WATANA HYDRO PROJECT:WATER QUALITY AND SEDIMENT DATA GAP ANALYSIS peare| DATE SOURCE AUTHOR TITLE LOCATION form=brief_list 2003 |United States USGS USGS 15294350 SUSITNA RAT |http://nwis.waterdata.usgs.gov/nwis/qwdata?site_no=1529 Geological Survey SUSITNA STATION AK 4350&agency_cd=USGS&inventory_output=0&rdb_invento ry_output=file&TZoutput=0&pm_cd_compare=Greaterthan &radio_parm_cds=all_parm_cds&format=html_table&qw_ attributes=O&qw_sample_wide=wide&rdb_qw_attributes= O&date_format=YYYY-MM- DD&rdb_compression=file&submitted_ form=brief_list 2010 |United States USGS USGS 15292000 SUSITNA RAT |http://waterdata.usgs.gov/nwis/uv/?site_no=15292000&PA Geological Survey GOLD CREEK AK DAILY RAmeter_cd=00065,00060,00062,72020 DISCHARGE,CUBIC FEET PER SECOND 2004 |URS Corp.URS Talkeetna Airport,Phase lJ https://sftp101.urscorp.com/human.aspx?OrglD=9164 Hydrologic/Hydraulic Assessment Table 4-2.Additional Documents Reviewed from Reference Library on AEA SharePoint Site. DOC_ID |Author Title Date Review Notes on RoR rer SUSAHIA.FOR LICENSE second review-review of electronic version included 127 ACRES HYDROELECTRIC PROJECT VOL.SA,EXHIBIT E,02/01/1983 vole (Uses naw)was already captured in summaryCHAPTERS1&2 ' BEFORE THE FERC,APPLICATION FOR LICENSE FOR MAJOR PROJECT SUSITNA reviewed-included water quality figures;data already128ACRESHYDROELECTRICPROJECTVOL.5B,EXHIBIT E,02/01/1983 captured in summary table;did not pull data from figures CHAPTER 2,(FIGURES) BEFORE THE FERC,APPLICATION FOR LICENSE .d tai |r b an129|aAcRES |FOR MAJOR PROJECT SUSITNA 02/01/1983 |T°viewee-contains general water quality observations;no HYDROELECTRIC PROJECT VOLUME 6A,specific data Le i RFP#2011-006 |URS |Tetra Tech,Inc.|Arctic Hydrology | WATANA HYDRO PROJECT:WATER QUALITY AND SEDIMENT DATA GAP ANALYSIS DOC_ID|Author Title Date Review Notes EXHIBIT E,CHAPTER 3 BEFORE THE FERC,APPLICATION FOR LICENSE FOR MAJOR PROJECT SUSITNA could not get document to open from SharePoint Site;130 ACRES HYDROELECTRIC PROJECT VOL.6B,EXHIBIT E,02/01/1983 assume no data appears that its only figures CHAPTER 3 (FIGURES) PRELIMINARY CHANNEL GEOMETRY,VELOCITY ... 192 R&M |AND WATERLEVEL DATA FOR THE SUSITNA _|04/22/1981 |Te¥iewed-no water quality data;contains WSE andRIVERAT_DEVIL'S CANYON velocity ENVIRONMENTAL STUDIES,SUBTASK 7.14, 296 TES ENVIRONMENTAL ANALYSIS OF ALTERNATIVE 10/01/1981 |reviewed-no water quality data ACCESS PLANS 346 ADF&G Neue RELATIONSHIPS DOLLY 05/01/1981 |reviewed-no water quality data 347 ADF&G ayonyUNG TAT RELATIONSHIPS 04/01/1981 |reviewed-no water quality data 349 ADF&G COND.WHITEFISH RELATIONSHIPS 04/01/1981 |reviewed-no water quality data 350 ADF&G Re ESPINE.MO ICKLEBACK RELATIONSHIPS 04/01/1981 |reviewed-no water quality data FISH AND WILDLIFE MITIGATION POLICY 385 ACRES NOVEMBER 1981,REVISED MARCH 1982,04/01/1982 |reviewed-no water quality data REVISED APRIL 1982 WATER RESOURCES ANALYSIS REVIEW OF .. . ..471 |ACRES |EXISTINGWATER RIGHTSINTHESUSITNA |12/01/1981 reviewed-no water quality data;water rights issueRIVERBASIN¥ See DAAREPORT VOL AQUATIC It reviewed-appears that contains water quality data in 585 |ADF&G |WaBITATAND INSTREAM FLOW STUDIES 01/01/1983 appends,however appenare not included in scanned1982PARTS1&2 ;om sloughs and tributaries ADF&G SU HYDRO AQUATIC STUDIES MAY reviewed-contains methods and site selection for WQ 885 ADF&G 1983 -JUNE 1984 PROCEDURES MANUAL 02/02/1984 |data during FY 1984;need to see if data report is FINAL DRAFT available Li G :RFP#2011-006 |URS |Tetra Tech,Inc.|Arctic Hydrology | WATANA HYDRO PROJECT:WATER QUALITY AND SEDIMENT DATA GAP ANALYSIS on le Fe ee DOC_ID |Author Title Date Review Notes THE DESTRUCTION OF MANITOBA'S LAST ..887 NEWBURY GREAT RIVER 01/01/1983 |reviewed-no water quality data reviewed-is companion document to DOC_585 and938ADF&G PHASE ILFINAL DRAFT 1982-83 (FY 83)08/31/1983 explains methods for collected WQ data and siteselection 1247 ACRES HYDROLOGY HYPOTHETICAL DAM BREAK 03/01/1982 |reviewed-no water quality dataANALYSIS reviewed-includes water quality data from 1981,would like to summarize along with data from 5 year study;WQ data associated with fisheries evaluation sites includesSUBTASK7.10 PHASE |FINAL DRAFT VOL.2 sloughs and tributaries;basic WQ parameters (temp,DO1308ADF&G PART 1 AQUATIC HABITAT AND INSTREAM 01/01/1981 6 .wi.P bo FLOW PROJECT pH,Conductivity,turbidity);Because of the age of thedata,it is not essential that it is summarized without the subsequent years.Data would be extremely outdated compared to conventional data from other resources. 1984 SUSITNA HYDRO AQUATIC STUDIES,reviewed-no water quality data in this report but 1450 ADF&G +REPORT #1 -ADULT ANADROMOUS FISH 01/01/1984 |included in Report No.3 from this series (need to obtain); INVESTIGATION:MAY -OCTOBER 1983 activities of ADF&G during 1983 open water season reviewed-contains water quality data from 1977 (most of PRELIMINARY ENVIRONMENTAL ASSESSMENT it unreadable),some USGS data that already is included1613|ADF&G |OF HYDROELECTRIC DEVELOPMENTON THE |03/01/1978 |1 SUm™mary table;Temp,DO,pH,Conductivity,turbidity SUSITNA RIVER data for slough and tributaries;most likely samelocationsasinearly80s.Data would be extremely outdated and not included in summary tables. ALASKA POWER AUTHORITY COMMENTS ON 1770 APA THE FERC DEIS OF MAY 1984 VOL.1 08/01/1984 |reviewed-no water quality data INTRODUCTION ALASKA POWER AUTHORITY COMMENTS ON 1772 APA TECHNICAL COMMIENTS..AQUATI .B 08/01/1984 |reviewed-no water quality data RESOURCES 1776 APA ALASKA POWER AUTHORITY COMMENTS ON 08/01/1984 |reviewed-no water quality data LY j RFP#2011-006 |URS |Tetra Tech,Inc.|Arctic Hydrology | WATANA HYDRO PROJECT:WATER QUALITY AND SEDIMENT DATA GAP ANALYSIS DOC_ID!Author Title Date Review Notes THE FERC DEIS OF MAY 1984 VOLUME 5 APPENDIX III -THERMAL ALTERNATIVES TO SUSITNA APA COMMENTS ON THE FERC DEIS MAY 1984 VOL.7 APPENDIX V -TEMPERATURE reviewed-no water quality data;simulated river1778APASIMULATIONS,SUSITNA RIVER,WATANA DAM 08/01/1984 temperatures TO SUNSHINE GAGING STATION,OPEN WATER A TRAM FLOW i VESTIGATIONS reviewed-contains no water quality data (only chapter 2) 1931 ADF&G (MAY-OCTOBER 1983)CHAPTER 2:CHANNEL 09/01/1984 vonparten te other ADRS ronortenn inet Scanned);GEOMETRY INVESTIGATIONS P year stuay ON THE FOOD CHAIN INSOME NORTH reviewed-no water quality data;literature concerning1954GRIMASSWEDISHRIVERRESERVOIRS01/01/1965 impacts to fish from hydro power projects in Sweden REPORT NO.4 ACCESS AND TRANSMISSION ...2049 |ADF&G |CORRIDOR AQUATIC INVESTIGATIONS (JULY-|01/01/1984 |Teviewed-no Susitna River WQ data;need Report No.3 OCTOBER 1983)(not scanned) Table 4-3.Documents of Interest (Possible Water Quality Data Source)But Not Available Electronically on AEA SharePoint Site. DOC_ID |Author Title Date Notes TASK 6 -DEVELOPMENT SELECTION,SUBTASK 6.05,..220 ACRES DEVELOPMENT SELECTION REPORT,FINAL 12/01/1981 |Could not locate on SharePoint Site TASK 6 -DEVELOPMENT SELECTION SUBTASK 6.05,.;221 ACRES DEVELOPMENT SELECTION REPORT,APPENDICES A-J 12/01/1981 |Could not locate on SharePoint Site SUSITNA HYDRO AQUATIC STUDIES PHASE I]BASIC DATA Report contains WQ data from 5 year REPORT VOL.4 AQUATIC HABITAT AND INSTREAM FLOW fisheries evaluation study conducted by 586 ADF&G |STUDIES 1982 APPENDIX A THRU C 01/01/1983 |ADF&G SUSITNA HYDRO AQUATIC STUDIES PHASE II BASIC DATA Report contains WQ data from 5 year REPORT VOL.4 AQUATIC HABITAT AND INSTREAM FLOW fisheries evaluation study conducted by 587 ADF&G |STUDIES 1982 APPENDIX D THRU J 01/01/1983 |ADF&G UNDERGROUND CABLE SYSTEMS:POTENTIAL .;746 D&M ENVIRONMENTAL IMPACTS DRAFT REPORT 08/31/1981 |Could not locate on SharePoint Site ia)RFP#2011-006 |URS |Tetra Tech,Inc.|Arctic Hydrology | WATANA HYDRO PROJECT:WATER QUALITY AND SEDIMENT DATA GAP ANALYSIS eee REPORT NO.3 AQUATIC HABITAT AND INSTREAM FLOW INVESTIGATIONS (MAY-OCTOBER,1983)CHAPTER 3: Report contains WQ data from 5 year fisheries evaluation study conducted by 1932 ADF&G |CONTINUOUS WATER TEMPERATURE INVESTIGATION 09/01/1984 |ADF&G REPORT NO.3 AQUATIC HABITAT AND INSTREAM FLOW Report contains WQ data from 5 year INVESTIGATIONS (MAY-OCTOBER 1983)CHAPTER 4:fisheries evaluation study conducted by 1933 ADF&G |WATER QUALITY INVESTIGATIONS 09/01/1984 |ADF&G TASK 29 AND 37 SUPPORT TECHNICAL REPORT CONTINUOUS coulg not locate onninarpin a one couldMNVESTIGATIONS2867|ADF&G WATER TEMPERATURE |06/01/1985 |continuous temperature monitoring RFP#2011-006 |URS |Tetra Tech,Inc.|Arctic Hydrology | WATANA HYDRO PROJECT:WATER QUALITY AND SEDIMENT DATA GAP ANALYSIS 4.2 Data Quality Data quality was evaluated,wherever possible,using companion information available from source documents.Quality objectives for existing data sets including:laboratory and field precision measurements,laboratory analysis accuracy,analytical bias,and matrix spikes are evaluated to determine comparability between data sets used in the data gaps evaluation.The consequence for using data that varies in comparability in this data gap analysis would bias conclusions by interpreting data with thresholds that were prescribed for use with lower method detection limits and reporting limits. Data that meet expectations for laboratory analysis performance or for measurement quality objectives in the field increases the sensitivity for detecting change and for correctly concluding water quality conditions.Combining multiple data sets that had differing data quality characteristics may result in improperly declaring a condition when using older data with higher reporting limits and matched with current criteria or thresholds. Generally,most of the data discovered and used for this data gap analysis is more than 20 years old. Many of the documents did not report data quality expressions and so an evaluation for comparability of data sets was not possible.The exception was the United States Geological Survey (USGS)data where long-term monitoring at select stations was completed in the drainage.The comparability of data among USGS stations was not in question,but the lack of DQOs from older data did not enable a comparison between USGS and other existing data sets.Any interpretations of data close to pollutant concentration criteria were interpreted as exceeding the standard.This conservative approach was taken in order to preserve the intent of water quality criteria and to suggest additional studies that should be conducted in order to advance definitive decisions. 4.3 Applicable Water Quality Standards Evaluation of water quality conditions began with determination of individual parameter exceedances and by identifying the location in the drainage where the exceedance occurred.The purpose for this analysis was to identify locations that presented potentially degraded conditions to important fish populations in the drainage and the conditions under which these occurred.The Alaska State Water Quality Standards were used for these comparisons against existing data as reported in Table 4-4. RFP#2011-006 |URS |Tetra Tech,Inc.|Arctic Hydrology | WATANA HYDRO PROJECT:WATER QUALITY AND SEDIMENT DATA GAP ANALYSIS Table 4-4.Alaska State Water Quality Standards for the Protection of Aquatic Life and Wildlife (18 AAC 70,May 2011). cobalt scale) Parameter Criteria Color Color or apparent color may not reduce the depth of the compensation point for (platinum-photosynthetic activity by more than 10%from the seasonally established norm for aquatic life.For all waters without a seasonally established norm for aquatic life,color or apparent color may not exceed 50 color units or the natural condition,whichever is greater. Fecal Coliform Not applicable. Bacteria Dissolved D.O.must be greater than 7 mg/I in waters used by anadromous or resident fish.In no Oxygen case may D.O.be less than 5 mg/l to a depth of 20 cm in the interstitial waters of gravel used by anadromous or resident fish for spawning (see note 2).For waters not used by anadromous or resident fish,D.O.must be greater than or equal to 5 mg/l.In no case may D.O.be greater than 17 mg/I.The concentration of total dissolved gas may not exceed 110%of saturation at any point of sample collection. Total Dissolved Solids TDS may not exceed 1,000 mg/l.A concentration of TDS may not be present in water if that concentration causes or reasonably could be expected to cause an adverse effect to aquatic life. pH May not be less than 6.5 or greater than 8.5.May not vary more than 0.5 pH unit from natural conditions. Temperature May not exceed 20°C at any time.The following maximum temperatures may not be exceeded,where applicable: Migration routes 15°C Spawning areas 13°C Rearing areas 15°C Egg &fry incubation 13°C For all other waters,the weekly average temperature may not exceed site-specific requirements needed to preserve normal species diversity or to prevent appearance of nuisance organisms. Turbidity May not exceed 25 NTU above natural conditions.For all lake waters,may not exceed 5 NTU above natural conditions. Additional data describing metals concentrations had been identified and aggregated into a summary table.The Alaska State Water Quality Standards for metals and other xenobiotics are reported in Table 4-5.Results from data comparisons for metals will inform on any elevated concentration in the drainage.Most metals water quality criteria are based on hardness concentrations measured at the same time.Due to the nature of the water quality summary and review,determining specific metals criteria for individual sample collections was not achievable.Therefore metal exceedances of state criteria were not determined.In Section 4.7 of this report,metal concentrations found in the Susitna River and tributaries were compared to known toxic thresholds providing valuable information on the impact of metals on fish populations. fa |RFP#2011-006 |URS |Tetra Tech,Inc,|Arctic Hydrology | WATANA HYDRO PROJECT:WATER QUALITY AND SEDIMENT DATA GAP ANALYSIS [: Table 4-5.Alaska State Water Quality Standards for Toxics and Other Deleterious Organic and tnorganic Substances (December 2008). Parameter Acute Criteria (CMC)Chronic Criteria (CCC) Aluminum,750 pg/L 87 ug/L Total recoverable (1-hr avg)(4-day avg) Ammonia,.1.77 to 28.1 Criteria are pH and temperature(total ammonia "eos 1 2 ..Criteria are pH dependent dependentnitrogenin(1-hr avg)(30-day avg)mg N/|) Arsenic,340 pg/L 150 tg/L dissolved (1-hr avg)(4-day avg) Barium No Criteria No Criteria Cadmium,Criteria Hardness Dependent®Criteria Hardness Dependent? dissolved (1-hr avg)(4-day avg) Chloride,860,000 pg/L 230,000 pg/L dissolved (1-hr avg)(4-day avg) Applies to dissolved chloride when Applies to dissolved chloride when associated with sodium.associated with sodium. Copper,Criteria Hardness Dependent?Criteria Hardness Dependent? dissolved (1-hr avg)(4-day avg) Iron No Criteria 1,000 pg/L Lead,Criteria Hardness Dependent®Criteria Hardness Dependent? dissolved (1-hr avg)(4-day avg) Manganese No Criteria No Criteria Mercury,1.4 pg/L 0.77 pg/L dissolved (1-hr avg)(4-day avg) ve Y,1.694 pg/L 0.9081 pg/L Nickel,Criteria Hardness Dependent®Criteria Hardness Dependent? dissolved (1-hr avg)(4-day avg) Selenium,See Note'5.0 pg/L Total recoverable (1-hr avg)(4-day avg) Zinc,Criteria Hardness Dependent?Criteria Hardness Dependent? dissolved (1-hr avg)(4-day avg) 15H values in the Susitna River range from 6.8 to 8.6.Using Appendix C in the Alaska Water Quality Criteria Manual for Toxic and Other Deleterious Organic and Inorganic Substances the criteria for Total Ammonia Nitrogen as N would range from 1.77 to 28.1 mgN/L. Chronic criteria for Ammonia should be calculated based on pH and temperature when early life stages of fish are present as shown in Appendix D of the Alaska Water Quality Criteria Manual for Toxic and Other Deleterious Organic and Inorganic Substances. 5To calculate dissolved metals criteria please refer to the table in Appendix A of the Alaska Water Quality Criteria Manual for Toxic and Other Deleterious Organic and Inorganic Substances. "The CMC =1/[(f1/CMC1)+(f2/CMC2)]where f1 and f2 are the fractions of total selenium that are treated as selenite and selenate,respectively,and CMC1 and CMC2 are 185.9 g/l and 12.82 g/l,respectively. RFP#2011-006 |URS |Tetra Tech,Inc.|Arctic Hydrology | WATANA HYDRO PROJECT:WATER QUALITY AND SEDIMENT DATA GAP ANALYSIS [a Turbidity measurements were summarized from existing data sets,but not evaluated against criteria and not interpreted further.The turbidity criterion is based on comparison against a natural background measurement and requires several observations from the same location within a specified period of time.Unless turbidity exceedances were identified at a location and within a reviewed report it was not possible to appropriately determine a turbidity exceedance from existing data.In addition,the Susitna River and several of the tributaries are glacially fed and already very turbid. 4.4 Locations Exceeding Water Quality Standards Identification of locations and timing of water quality exceedance was compared against fish population presence in each ofthe four reaches.High concentrations of conventional parameters and/or metals concentrations were initially screened and identification of location and time of year when water quality exceedances may have occurred.The next step in evaluation of existing data was the comparison between fish population presence and exceedance of toxics threshold concentrations.Both evaluations measure effects of water quality conditions on aquatic life,both direct and indirect assessments of impairments.Some of the high concentrations for metals appear to exceed toxics criteria,but the geologic setting of this river drainage is a major influence on water chemistry. Earlier studies indicated naturally elevated metals background concentrations from select sampling sites throughout the drainage (Harza-Ebasco 1986).The following was an excerpt taken from this document explaining which of the metals had elevated concentrations and the potential activities that may have been related to these toxics: The original License Application (APA 1983a,b)reviews the concentrations of metals in Susitna River water and evaluates them using published criteria and guidelines (Alaska Administrative Code (ACC) 1984;EPA 1976;McNeely et al.1979;Sittig 1981).Many natural metal concentration exceeded these criteria and guidelines.As stated in the original License Application,the measured levels of heavy metals in the Susitna River represent natural conditions.With the exception of some placer mining operations,the watershed supports no significant industry,agriculture,or urbanization.It was concluded,consequently,that the exceedance of water quality criteria by certain metal concentrations is representative of a naturally affected aquatic ecosystem.Nevertheless,the high levels of certain heavy metals warrant further investigation.Metals which exceeded applicable criteria included both dissolved and total recoverable aluminum (Al),cadmium (Cd),copper (Cu),manganese (Mn),mercury (Hg),and zinc (Zn).In addition,the dissolved fraction of bismuth (Bi)and the total recoverable quantities of iron (Fe),lead (Pb),and nickel (Ni)also exceeded the criteria. Temperature data collection has been the most abundant type of water quality evaluation conducted in the Susitna River drainage.Recently,tributaries have been the focus of many water temperature studies as this water quality parameter may represent the greatest threat of impairments to the mainstem condition (Table 4-6 through Table 4-8 and Figure 4-1).Highlighted numerical values in Table 4-6 and Table 4-7 represent temperature violations at a tributary location during a particular month.The summer months (May through September)represent the most stressful period of the year for impaired water quality conditions.According to state water quality standards,the maximum temperature that RFP#2011-006 |URS |Tetra Tech,Inc.|Arctic Hydrology | WATANA HYDRO PROJECT:WATER QUALITY AND SEDIMENT DATA GAP ANALYSIS must not be exceeded in waters where spawning activity occurs is 13°C.This was the criterion used to evaluate tributary temperatures within the Susitna River Basin since it is known that fish populations use the tributaries and sloughs as spawning areas. A limited number of conventional water quality parameters have been collected at locations throughout the drainage.Most ofthis information had been collected for projects 30-40 years ago (1970's -1980's) and does not represent a complete characterization of conventional water quality conditions.Water quality indicators that have been measured periodically at mainstem Susitna River and tributary stations are nutrients.Mainstem nutrient concentrations were low in almost all cases and the age of this data is reflected in poor detection limits reported in original literature (e.g.,ortho-phosphate <0.1 mg/L ). Examination for temporal or spatial patterns in both nitrate and phosphate concentrations indicated a potential relationship with salmon carcass presence.The temporary increase in nitrate concentrations (e.g.,Talkeetna River,Appendix B-1)occurs during the fall season and coincides with presence of the salmon spawning season.Influence ofthe fisheries on surface water quality is measurable in some locations of the drainage. Almost all tributaries exceeded the spawning temperature criteria during the summer months in 2008 and 2009 (Table 4-6 and Table 4-7).The highest summer water temperatures were seen in Alexander Creek and Kroto Creek.Alexander Creek is located in Reach 4 at the lower end of the watershed while Kroto Creek is located in Reach 2 and below major river tributaries (e.g.Chulitna River and Talkeetna River).Due to the locations of these tributaries within the basin,temperature modifications to the mainstem are unlikely to occur.The coldest water temperatures recorded during the summer months were in the East Fork of the Chulitna River.This tributary is located at the northern edge of the basin. Smaller tributaries to the Susitna River serve primarily as coldwater refugia to salmon and steelhead populations,especially during the summer months. RFP#2011-006 |URS |Tetra Tech,Inc.|Arctic Hydrology | WATANA HYDRO PROJECT:WATER QUALITY AND SEDIMENT DATA GAP ANALYSIS = Table 4-6.2008 Susitna River Basin Temperatures (Cook Inlet Keepers,via personal communication). Station Name © =@ ry y ®pad wu2)si]et]e]e2]¢e]2]5]8 lee]8]ao]%oO @ vo o oO P=©>ras]Vc pas w 2MonthTemperature(°C)5 oO Oo oe)c Ss x 3 7 So v E oO =2 2)¥|Bs 8 |=5 |ef]g 9 3 c wo Ss 2 a we Q ==o =a 2s/e/S5)5)/8 1s]e]2]es |S5}£|8]s<a s 6 |BE |2 -2oZ=e uw Max 16.0 17.1 11.8 14.3 13.9 10.2 19.3 12.3 13.3 17.2 17.2 13.5 -- June Min 11.0 5.1 3.2 11.0 5.6 2.6 13.2 5.9 5.2 8.9 10.0 4.5 -- Mean 13.9 10.6 6.7 12.9 9.4 5.9 16.0 8.9 8.9 12.3 13.3 8.5 -- Max 22.0 19.6 15.3 20.8 15.7 11.6 20.4 15.6 16.5 19.8 19.2 17.0 14.8 July Min 11.1 9.8 4.5 10,1 7.9 4.6 10.9 77 8.4 10.2 11.9 7.6 7.6 Mean 14.3 13.6 8.8 13.8 10.7 7.3 14.5 10.4 10.9 13.1 14.2 11.0 10.2 Max 18.3 16.5 13.7 16.1 13.9 10.5 20.3 13.8 14.5 15.0 16.0 13.2 13.4 August Min 12.6 10.7 5.4 10.0 8.1 4.5 10.6 8.3 8.0 9.5 11.1 79 8.1 Mean 15.1 13.1 9.7 13.3 10.6 7.2 14.5 10.5 10.7 12.3 13.4 10.7 10.5 Max --15.2 11.6 13.5 11.4 9.2 17.2 11.2 11.9 12.9 12.5 12.1 11.2 September Min --5.2 0.2 2.0 1.9 -0.1 4.9 1.7 2.0 3.8 3.4 1.6 2.3 Mean -10.4 6.6 9.0 7.7 5.2 10.1 7.6 8.1 9.1 9.5 7.8 7.7 Note:Temperatures may not exceed 20°C at any time.Applicable temperature criteria for protection of the salmon life cycle are as follows:migration routes 15°C,spawning areas 13°C,rearing areas 15°C,egg &fry incubation 13°C. RFP#2011-006 |URS |Tetra Tech,Inc.|Arctic Hydrology | WATANA HYDRO PROJECT:WATER QUALITY AND SEDIMENT DATA GAP ANALYSIS .alfatoetone Table 4-7.2009 Susitna River Basin Temperatures (Cook Inlet Keepers,via personal communication). Station Name @ ri rr Month Temperature (°C)5 o o S E G g 8 3 3 o 9 re E Q el e/ele]efe"}3°)2 |e |se)e)2]£/*|s)é)ele je |e}sis")2)2]8 a Ee Max -7.0 6.4 17.2 12.8 6.5 18.1 8.1 10.5 -16.3 6.0 - May Min --5.5 3.2 5.3 2.0 3.1 9.5 5.8 0.1 --2.8 4.3 -- Mean --6.2 4.7 10.0 7.2 4.6 12.6 6.9 4.8 --9.5 5.2 - Max 22.1 18.9 14.9 19.6 15.2 11.5 20.7 14.4 15.1 --18.8 16.0 13.9 June Min 10.9 6.2 3.6 6.7 5.6 3.3 9.6 6.3 5.2 --9.2 4.2 7.1 Mean 14.9 11.9 8.3 14.0 11.0 6.8 15.6 10.7 10.2 --13.8 10.1 10.2 Max 22.6 22.8 20.7 24.3 18.8 15.5 24.5 19.5 18.8 18.1 22.2 19.9 18.8 July Min 13.1 11.9 7.8 13.9 10.3 6.2 14.1 11.0 10.0 12.4 13.6 10.3 10.6 Mean 18.1 17.1 13.9 17.8 14.1 10.5 18.7 14.6 14.2 14.7 17.3 14.8 14.3 Max 18.1 19.1 17.3 17.3 15.1 13.7 17.8 15.8 16.4 16.9 17.7 16.5 16.3 August Min 9.5 10.7 5.8 9.3 8.8 3.8 11.6 8.7 9.2 9.5 11.1 8.0 8.9 Mean 14.6 13.9 10.4 13.1 11.4 8.1 13.7 11.7 11.8 12.6 13.7 11.4 11.8 Max 17.3 14.3 11.5 13.1 11.2 9.3 12.6 12.1 13.1 17.5 13.2 11.2 12.6 September Min 2.9 5.2 0.8 7.7 6.9 1.0 4.8 2.8 2.9 7.1 4.2 2.3 3.5 Mean 10.1 10.2 6.7 10.4 9.6 5.5 9.5 7.9 8.4 10.5 9.4 7.8 8.2 26)RFP#2011-006 |URS |Tetra Tech,Inc.|Arctic Hydrology | WATANA HYDRO PROJECT:WATER QUALITY AND SEDIMENT DATA GAP ANALYSIS Station Name x 4wsxSwo@ o 3)S ny 7 =@2|/sf]sj)}s|e2 {8 |5 |2 |3es/3]6 |% °id @ v v v =2._|Gx >'s)es 5 w £Month Temperature (°C)S Pa S 5 =Oo|8s S ©OD bd =OoaS”n ®2 =>|ao =c o 0 o oO 2 c S rat 3 ra 5 =5 S %ox a 4ooOrya(°)o VU =y OG ro)ae)o >3 ral o uw 2 Cc o ¢Qa Y =o a Oo G 2 2 a x eo |s =}&£$s ==a o x Fe]=F 5 wi der}oe- Max --7.7 4.7 =--4.8 6.4 6.5 ------6.7 -- October Min --4.7 0.9 ----0.0 2.4 1.7 ------1.9 - Mean --6.3 3.0 ----2.7 5.0 4.2 ------4.1 -- Note:Temperatures may not exceed 20°C at any time.Applicable temperature criteria for protection of the salmon life cycle are as follows:migration routes 15°C,spawning areas 13°C,rearing areas 15°C,egg &fry incubation 13°C. i :RFP#2011-006 |URS |Tetra Tech,Inc.|Arctic Hydrology | WATANA HYDRO PROJECT:WATER QUALITY AND SEDIMENT DATA GAP ANALYSIS Table 4-8.Location of continuous temperature monitoring data on tributaries of the Susitna River mainstem (Cook Inlet Keeper,2008 and 2009). Stream Name Description Latitude Longitude Alexander Creek Approx.2 miles upstream from Susitna River 61.44000 -150.59600 Byers Creek Upstream from Park's Highway 62.71158 -150.20407 Cache Creek 1/2 mile downstream from landing strip 62.38900 -151.08100 Chijuk Creek At Oilwell Road Crossing 62.07963 150.58314 Deception Creek Upstream from Willow-Fishhook Road 61.76200 -150.03400 East Fork Chulitna River Downstream from Park's Highway 63.14500 -149.42100 Kroto (Deshka)Creek 1 mile upstream from Susitna River 61.74000 -150.32000 Little Willow Creek 0.25 miles downstream from Parks Highway 61.81000 -150.09900 Montana Creek End of Access Road South of Helena 62.12800 -150.01900 Moose Creek (Talkeetna)At Oilwell Road Crossing 62.22900 -150.44100 Trapper Creek At Bradley Road Crossing 62.26600 -150.18400 Troublesome Creek Downstream from Park's Highway 62.62700 -150.22700 Willow Creek 0.25 miles upstream from Susitna River 61.78000 -150.16100 ©RFP#2011-006 |URS |Tetra Tech,Inc.|Arctic Hydrology | WATANA HYDRO PROJECT:WATER QUALITY AND SEDIMENT DATA GAP ANALYSIS abel joose?ue}re AP eenen%Bye pot CEES A Ny 0XSeBe Figure 4-1.Mat-Su temperature monitoring locations,corresponding watersheds are highlighted. Water quality summary data tables (Appendix B)were reviewed for concentrations of parameters that exceeded water quality criteria.Summer temperature measurements primarily at tributary stations exceeded criteria in the lower three reaches (reaches 2-4)in some cases for spawning and others, migration.High aluminum concentrations occurred at the upper three reaches (reaches 1-3)and forms of mercury had exceeded criteria only at lower mainstem stations.High background concentrations of metals have been noted from past studies and may have an effect on the fisheries should these elements become bioavailable.In areas like reach 4 where metals criteria had been exceeded,factors that promote elemental forms that become bioavailable are present like low dissolved oxygen concentrations and pH (Table 4-9). Table 4-9.Location of water quality criteria exceedances in the Susitna River drainage. Bounds of Reach Reach Water Quality Criteria .;.General Description(Susitna River Miles)Number Exceedance Upper Susitna River,Aluminum 313-184 1 including headwaters and fron tributaries above the proposed Watana dam RFP#2011-006 |URS |Tetra Tech,Inc.|Arctic Hydrology | WATANA HYDRO PROJECT:WATER QUALITY AND SEDIMENT DATA GAP ANALYSIS rane Lee ayes Bounds of Reach Reach .Water Quality Criteria ...General Description(Susitna River Miles)Number Exceedance site Middle Susitna River and {Total Dissolved Gas tributaries through Devil's Temperature (for Migration) 184 -150 2 Canyon and below the proposed Watana Dam site Aluminum Middle Susitna River and Temperature for Migration tributaries from the Aluminum 150 -99 3 mouth of Devil's Canyon fron to the Susitna-Chulitna rota)Mercury (Mainstem at Gold -Talkeetna confluence Creek) Temperature for Spawning Lower Susitna River from Talkeetna River) 99-0 4 Susitna -Chulitna -Dissolved Oxygen Talkeetna confluence to [pH mouth at Cook Inlet ron Mercury The State of Alaska periodically prepares a list of impaired water bodies (303d list)that reports the type and magnitude of pollution problems.The impairments are presented on the ADEC web site and can be found at the following address: http://www.dec.state.ak.us/water/wasar/Docs/2010impairedwaters.pdf The Susitna River and associated tributaries are not listed by the State of Alaska as impaired. 4.5 Timing of Pollutant Introduction Evaluation of several groups of water quality parameters were previously compared against state criteria and are compared against biological toxics thresholds for salmon species using the no observed effects concentrations (NOECs)and lowest observed effects concentrations (LOECs).In addition, longitudinal station comparisons described how water quality conditions changed as the Susitna River flows downstream through distinct physical settings and influenced by tributary conditions. Pollutant introduction can enter the Susitna River mainstem during many of the months of the year and remain sequestered until water quality conditions that favor mobilization occurs.Timing for pollutant mobilization can vary based on location in the drainage such as in the mainstem and tributaries to the Le _g RFP#2011-006 |URS |Tetra Tech,Inc.|Arctic Hydrology | cient:-einer eta:WATANA HYDRO PROJECT:WATER QUALITY AND SEDIMENT DATA GAP ANALYSIS r oe eee UY Susitna River.The physical settings of each reach will have a major influence on how water quality conditions could materialize and become factors of pollutant mobilization.The descriptions of these settings for the length of the Susitna River and the fisheries that could be affected by water quality impairments are combined in Table 4-10. Mainstem Distinct settings were identified using physical channel characteristics and surrounding topography of the mainstem Susitna River.A previous strategy for naming distinct reaches was suggested by Acres (1983)in the FERC Application for License (Table 4-10). Tributaries Tributaries to the Susitna River potentially represent sources of pollution that would be identified as data is analyzed from mainstem stations.The tributary rivers and streams tend to be influenced by human development in the watershed and so are important focal points for further evaluation.The connectivity between the mainstem Susitna River and the tributaries are further examined for value as fish population refugia and limitations to this type of access by the fisheries from pollution barriers,if present. Bi5 "*)RFPH2011-006|URS |Tetra Tech,Inc.|Arctic Hydrology | WATANA HYDRO PROJECT:WATER QUALITY AND SEDIMENT DATA GAP ANALYSIS Table 4-10.Presence of fish species by Susitna River reach and segment. 152 149-144 144-139 139-129.5 129,5-119 Devil's:Canyon Proposed Site... 0.00195 Single channel confined by valley walls. Frequent bedrock control points.ooSplitchannelconfinedbyvalleywalland: River Average Mile Bed Segment Description Fish Species Present (RM)Reach Slope 3130 |_|Headwaters..S :313--233 =Upper Drainage Basinee Grayling,Rainbow Trout,Longnose Suckeroe&Oh Grayling,Burbot,Longnose Sucker,Round and Humpback - -oe ee eee Whitefish,Slimy Sculpin,Dolly Varden,LakeTrout,Chinook ee184-223 |Area of Probable Inundation _Salmon -Dolly Varden,Humpback Whitefish,Eulachon,'Rainbow Trout, s meenDam Site Chinook Salmon,_Longnose Sucker -3s Dolly Varden,Humpback Whitefish,Eulachon,Rainbow Trout,:Chinook Salmon,Longnose Sucker...Chum,Coho,Chinook,and Pink Salmon,Dolly Varden, Humpback Whitefish,Eulachon,Rainbow Trout,Burbot, Longnose Sucker -Chum,Coho,Chinook,and Pink Salmon,Dolly Varden, 0.00173 occupy east floodplain.west valley wall.Subchannels and sloughs :. 0.00260 Humpback Whitefish,Eulachon,Rainbow Trout,Burbot,terraces. Ss.Split channel confined occasionally by :3 0.00210 terraces and valley walls.Main channels,Chum,Coho,Chinook,Pink,and Sockeye Salmon,Dolly ,side channels and sloughs occupy valley Varden,Humpback Whitefish,Eulachon,Rainbow Trout, bottom."cp sunsssrinay|Burbot,Longnose Sucker"Splitchannelwith occasionaltendencyto |a braid.Main channel frequently flows against |Chum,Coho,Chinook,Pink,and Sockeye Salmon,DollyVarden,Humpback Whitefish,Eulachon,Rainbow Trout,Burbot,Longnose Sucker ==: RFEP#2011-006 |URS |Tetra Tech,Inc.|Arctic Hydrology |