fish entrainment and turbine survival evaluation for tillery … · 2015. 7. 22. · the epri...

© 2005 Progress Energy

Yadkin-Pee Dee River Hydroelectric Project FERC No. 2206

FISH ENTRAINMENT AND TURBINE SURVIVAL EVALUATION FOR TILLERY

AND BLEWETT FALLS DEVELOPMENTS

Water Resources Working Group Issue No. 16 - Desktop Entrainment Study

PROGRESS ENERGY

NOVEMBER 2005

i

TABLE OF CONTENTS

Section Title Page No. ACRONYM LIST ....................................................................................................AL-1 EXECUTIVE SUMMARY ..........................................................................................ES-1 SECTION 1 - INTRODUCTION .................................................................................... 1-1 SECTION 2 - STUDY OBJECTIVES ............................................................................. 2-1 SECTION 3 - SITE DESCRIPTION ............................................................................... 3-1 SECTION 4 - METHODS ............................................................................................ 4-1 SECTION 5 - RESULTS AND DISCUSSIONS................................................................. 5-1 5.1 Project Fisheries ............................................................................................................ 5-1

5.1.1 Fish Populations and Species of Interest......................................................... 5-1 5.1.2 Fisheries Management History and Goals ...................................................... 5-3 5.1.3 Characteristics of Selected Species................................................................. 5-5

5.2 Entrainment and Survival Potential............................................................................. 5-10 5.2.1 Factors Affecting Fish Entrainment Abundance........................................... 5-10 5.2.2 Factors Affecting Turbine Survival/Mortality .............................................. 5-18

SECTION 6 - SUMMARY ........................................................................................... 6-1 6.1 Tillery Development...................................................................................................... 6-1 6.2 Blewett Falls Development ........................................................................................... 6-1 6.3 General Summary.......................................................................................................... 6-2 SECTION 7 - REFERENCES........................................................................................ 7-1 APPENDICES APPENDIX A - WATER RWG, ISSUE NO. 16, DESKTOP ENTRAINMENT STUDY -

RESERVOIR AND ANADROMOUS FISH

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LIST OF FIGURES

Figure Title Page No. Figure 3-1 Yadkin-Pee Dee River Project location map. ...................................................... 3-2

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LIST OF TABLES

Table Title Page No. Table 3-1 Summary of Tillery and Blewett Falls turbine-generator equipment and

summary of turbines from EPRI (1997). ............................................................. 3-3 Table 3-2 Reservoir and intake characteristics of developments in the Yadkin-Pee Dee

River Hydroelectric Project. ................................................................................ 3-4 Table 5-1 Fish taxa collected in the vicinity of the Yadkin-Pee Dee River Hydroelectric

Project (Blewett Falls and Tillery Hydroelectric Developments) including Lake Tillery and Blewett Falls Lake, 1986-2002. ............................................... 5-2

Table 5-2 Mean number and weight (Kg) per 24 hours for fish collected with quarterly gillnetting from Tillery Lake during 2000. .......................................................... 5-7

Table 5-3 Mean number and weight (Kg) per 24 hours for fish collected with quarterly gillnetting from Blewett Falls Lake during 2001................................................. 5-8

Table 5-4 Metric scoring for indices of relative entrainment potential for Yadkin-Pee Dee River Hydroelectric Developments (after GeoSyntec 2004). .................... 5-12

Table 5-5 Average annual entrainment densities for Yadkin-Pee Dee River Project fish species of interest from EPRI (1997) entrainment database. Annual density shown as fish per million cubic feet of water. ................................................... 5-13

Table 5-6 Mean monthly entrainment densities of Clupeids from EPRI (1997) database. Monthly density shown as fish per million cubic feet of water......................... 5-13

Table 5-7 Mean monthly entrainment densities of Ictalurus from EPRI (1997) database. Monthly density shown as fish per million cubic feet of water......................... 5-14

Table 5-8 Mean monthly entrainment densities of centrarchids from EPRI (1997) database. Monthly density shown as fish per million cubic feet of water. ....... 5-15

Table 5-9 Mean monthly entrainment densities of moronids from EPRI (1997) database. Monthly density shown as fish per million cubic feet of water. ....... 5-16

Table 5-10 Mean monthly entrainment densities of non-migratory American eel from EPRI (1997) database. Monthly density shown as fish per million cubic feet of water. ............................................................................................................. 5-16

Table 5-11 Mean monthly entrainment densities of Moxostoma from EPRI (1997) database. Monthly density shown as fish per million cubic feet of water. ....... 5-17

Table 5-12 Metric scoring for indices of relative turbine mortality potential for Yadkin-Pee Dee River hydroelectric developments (after GeoSyntec 2004). ............... 5-20

Table 5-13 Summary of 17 Francis turbine-generators from EPRI (1997) database used to estimate entrainment survival. ....................................................................... 5-20

Table 5-14 Turbine passage survival estimates for Yadkin-Pee Dee River Project fish species of interest from EPRI (1997) entrainment database.............................. 5-21

AL-1

Acronym List Federal/State Agencies Advisory Council on Historic Preservation (ACHP) Federal Aviation Administration (FAA) Federal Energy Regulatory Commission (FERC) National Park Service (NPS) National Marine Fisheries Service (NMFS) National Oceanic and Atmospheric Administration (NOAA) National Resource Conservation Service (NRCS) formerly known as Soil Conservation Service National Weather Service (NWS) North Carolina Department of Environment and Natural Resources (NCDENR) North Carolina Environmental Management Commission (NCEMC) North Carolina Department of Natural and Economic Resources, Division of Environmental Management (NCDEM) North Carolina Division of Parks and Recreation (NCDPR) North Carolina Division of Water Resources (NCDWR) North Carolina Division of Water Quality (NCDWQ) North Carolina Natural Heritage Program (NCNHP) North Carolina State Historic Preservation Officer (NCSHPO) North Carolina Wildlife Resources Commission (NCWRC) South Carolina Department of Natural Resources (SCDNR) South Carolina Department of Health and Environmental Control (SCDHEC) State Historic Preservation Office (SHPO) U.S. Army Corps of Engineers (ACOE) U.S. Department of Interior (DOI) U.S. Environmental Protection Agency (USEPA) U.S. Fish and Wildlife Service (USFWS) U.S. Geological Survey (USGS) U.S. Department of Agriculture (USDA) U.S. Forest Service (USFS) Other Entities Alcoa Power Generating, Inc., Yadkin Division (APGI) Atlantic States Marine Fisheries Commission (ASMFC) Electric Power Research Institute (EPRI) Progress Energy University of North Carolina at Chapel Hill (UNCCH) Facilities/Places Yadkin - Pee Dee River Project (entire two-development project including both powerhouses, dams and impoundments) Blewett Falls Development (when referring to dam, powerhouse and impoundment) Blewett Falls Dam (when referring to the structure) Blewett Falls Hydroelectric Plant (when referring to the powerhouse) Blewett Falls Lake (when referring to the impoundment) Tillery Development (when referring to dam, powerhouse and impoundment)

Acronym List

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Tillery Dam (when referring to the structure) Tillery Hydroelectric Plant (when referring to the powerhouse) Lake Tillery (when referring to the impoundment) Documents 401 Water Quality Certification (401 WQC) Draft Environmental Assessment (DEA) Environmental Assessment (EA) Environmental Impact Statement (EIS) Final Environmental Assessment (FEA) Initial Consultation Document (ICD) Memorandum of Agreement (MOA) National Wetland Inventory (NWI) Notice of Intent (NOI) Notice of Proposed Rulemaking (NOPR) Preliminary Draft Environmental Assessment (PDEA) Programmatic Agreement (PA) Scoping Document (SD) Shoreline Management Plan (SMP) Laws/Regulations Clean Water Act (CWA) Code of Federal Regulations (CFR) Electric Consumers Protection Act (ECPA) Endangered Species Act (ESA) Federal Power Act (FPA) Fish and Wildlife Coordination Act (FWCA) National Environmental Policy Act (NEPA) National Historic Preservation Act (NHPA) Terminology Alternative Relicensing Process (ALP) Cubic feet (cf) Cubic feet per second (cfs) Degrees Celsius (C) Degrees Fahrenheit (F) Dissolved oxygen (DO) Feet (ft) Gallons per day (gpd) Geographic Information Systems (GIS) Gigawatt Hour (GWh) Global Positioning System (GPS) Grams (g) Horsepower (hp) Kilogram (kg) Kilowatts (kW)

Acronym List

AL-3

Kilowatt-hours (kWh) Mean Sea Level (msl) Megawatt (MW) Megawatt-hours (MWh) Micrograms per liter (µg/L) Milligrams per liter (mg/L) Millimeter (mm) Million gallons per day (mgd) National Geodetic Vertical Datum (NGVD) National Wetlands Inventory (NWI) Non-governmental Organizations (NGOs) Ounces (oz.) Outstanding Remarkable Value (ORV) Parts per billion (ppb) Parts per million (ppm) Pounds (lbs.) Power Factor (p.f.) Probable Maximum Flood (PMF) Project Inflow Design Flood (IDF) Rare, Threatened, and Endangered Species (RTE) Ready for Environmental Assessment (REA) Resource Work Groups (RWG) Revolutions per Minute (rpm) Rights-of-way (ROW) River Mile (RM) Stakeholders (federal and state resource agencies, NGOs, and other interested parties) Volts (V)

ES-1

Executive Summary Progress Energy is currently relicensing the Blewett Falls and Tillery hydroelectric developments (i.e., Yadkin-Pee Dee River Hydroelectric Project, FERC No. 2206) with the Federal Energy Regulatory Commission (FERC). As part of the FERC relicensing process, Progress Energy established Resource Work Groups (RWGs) to identify environmental issues associated with project operations and develop study plans specific to Project lands, lakes, and tailwaters. The Water RWG identified the need for a desktop analysis of the potential for fish entrainment and turbine mortality associated with both hydroelectric developments. Progress Energy agreed to conduct a desktop entrainment study as part of its relicensing process (i.e., Water RWG, Issue No. 16, Desktop Entrainment Study - Reservoir and Anadromous Fish; Appendix A). In addition, the potential effects of entrainment on five species of diadromous fish were evaluated (hickory shad, blueback herring, American shad, American eel, shortnose sturgeon, and striped bass) (Progress 2003b). These species are potential future restoration target species in the Yadkin-Pee Dee River Basin diadromous fish restoration plan. A desktop entrainment and survival study typically involves a thorough review of published literature from field studies. Following the “Class of ’93” (a disproportionate number of Federal Energy Regulatory Commission [FERC] licensed project licenses that expired in 1993), much of the available empirical information, including difficulties in conducting entrainment studies was collected and compiled by the Electric Power Research Institute (EPRI), and published in 1997 as a turbine entrainment and survival database. The EPRI process followed for this assessment of entrainment potential and turbine passage survival was: ■ Compile and summarize life history information on all species of interest; ■ Characterize physical and biotic factors at the development sites; ■ Factors affecting entrainment potential at each project were qualitatively characterized as low,

medium, or high; and ■ The EPRI (1997) entrainment and survival database was referenced and species specific

entrainment and survival rates were evaluated on a monthly and annual time scale. The size and number of fish entrained at a hydroelectric development is related to a variety of physical factors, such as plant flow, intake and forebay configuration, intake depth, intake approach velocities, trashrack spacing, plant operating mode, reservoir temperature and dissolved oxygen stratification patterns, and proximity to fish feeding and rearing habitats. In conjunction with physical factors, biotic factors also influence a species susceptibility to entrainment. These variables include diurnal and/or seasonal movement patterns, fish size, swimming speed, fish behavior, life history requirements, relative size of the population, and density-dependent influences. Like entrainment, survival of turbine entrained fish depends on the physical characteristics of the turbine system, such as head, turbine size and design, runner speed, wicket gate openings, number of runner blades, runner blade angle, gap size, and water flow through the turbine. Many of these factors are causes of mechanical injury. Therefore, it has been generally accepted that survival depends on size, physiology, and behavior of entrained fish, as it relates to the sources of mechanical injury described above.

Executive Summary

ES-2

Each reservoir was examined individually with respect to multi-metric indices developed based on the above characteristics. This approach borrowed metric scoring concepts from widely used and accepted rapid bioassessment protocols such as the Index of Biotic Integrity used to characterize water resource conditions. Each metric was subjectively assigned a score of 1, 3 or 5, with lower values assigned to features with less impact on potential for entrainment. Metrics with similar characteristics at other projects in the EPRI database were scored similarly in this analysis. Species were selected for evaluation based on their relative abundance in the Project area, importance in resource management objectives, and availability of existing information. Species evaluated included resident species and diadromous species proposed for restoration in project waters. The overall entrainment potential of both project developments was rated “moderate” to “high.” As expected, small fish (15 inches). In fact, most studies have shown that entrainment is highest for fish less than 4 inches. Small- and medium-sized shad (clupeids) generally have the highest potential for entrainment in reservoirs where they are abundant due to their schooling behavior in the upper water column. Mean annual entrainment potential for small channel catfish and black crappie were also considered “high” based on the results from 41 entrainment studies reviewed for this analysis. Mean annual entrainment potential of small (

Executive Summary

ES-3

delayed stress mortality. Overall species-independent entrainment survival was estimated at 85 to 95 percent depending on fish size. Based on current reservoir fish population assessments, the fishery resources are healthy at the population level (Dorsey et al. 2004; Harland 2004a, 2004b; Progress Energy 2003a, 2004). Thus, there is no evidence that current levels of entrainment at these projects are having a negative impact on the fishery resource at the population level. Diadromous species proposed for restoration in project waters will likely have a high potential for entrainment because of requisite downstream migrations. While the likelihood of survival should be relatively good, downstream fish passage provisions would effectively increase survival of downstream migrants.

1-1

Section 1 - Introduction Progress Energy is currently relicensing the Blewett Falls and Tillery hydroelectric developments (i.e., Yadkin-Pee Dee River Hydroelectric Project, FERC No. 2206) with the Federal Energy Regulatory Commission (FERC). As part of the relicensing process, Progress Energy established Resource Work Groups (RWGs) to identify environmental issues associated with project operations and develop study plans specific to project lands, lakes, and tailwaters. The Water RWG identified the need for a desktop analysis of the potential for fish entrainment and turbine mortality associated with both hydroelectric developments. Progress Energy agreed to conduct a desktop entrainment study as part of its relicensing process (i.e., Water RWG, Issue No. 16, Desktop Entrainment Study - Reservoir and Anadromous Fish; Appendix A). The fish entrainment study plan specified evaluation of the potential for fish entrainment and survival relative to the physical features and fish communities of the developments in the Project. Entrainment, as used throughout this report, is the passage of organisms (in this case, fish) through water intakes (FERC 1995). In the case of the Project developments, fish entrained at the intakes are passed through the penstock and turbine, and discharged to the downstream tailwater. Some of the fish drawn into hydro turbine intakes may be injured or killed. Studies designed to measure the impact to fish passing through hydro turbines are called fish entrainment and survival studies. Fish survival is the complement to fish mortality. In other words, a survival rate of 95 percent is equivalent to a 5 percent mortality rate.

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Section 2 - Study Objectives The objectives of this study are two-fold. First, evaluate potential turbine entrainment effects on the major, representative resident fish species and any species proposed for diadromous restoration upstream of the Project dams. A second objective is to determine the relative health of the resident fish populations and assess whether the qualitative level of turbine entrainment poses a significant impact to these populations. This study was conducted in accordance with the study plan developed with the Water RWG for this issue (Progress Energy 2003b, 2004).

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Section 3 - Site Description The Project is located on the Yadkin-Pee Dee River in south-central North Carolina (Figure 3-1). The Yadkin-Pee Dee River basin is the second largest in North Carolina covering 7,213 square miles as measured at the North Carolina-South Carolina state line (NCDWQ 1998 as cited by Progress Energy 2003). The Yadkin-Pee Dee River originates near the town of Blowing Rock and flows northeasterly for approximately 100 miles from the Blue Ridge Mountains into the Piedmont physiogeographic region. As the river turns southeast, it enters an area in central North Carolina that has experienced considerable urban growth. This growing urban area that extends from Charlotte to Raleigh/Durham is known as the “Piedmont Crescent” (ASU 1999 as cited by Progress Energy 2003). Just to the south of the Piedmont Crescent, the river enters an area known as the Uwharrie Lakes Region. This region is named for the chain of six reservoirs located along this reach of the Yadkin-Pee Dee River, two of which are Lake Tillery and Blewett Falls Lake. It is in this region that the Uwharrie River joins the Yadkin River at the upper end of Lake Tillery to form the Pee Dee River. The Project developments, Tillery and Blewett Falls, are located approximately at river mile (RM) 218 and 188, respectively. The primary purpose of the Project is to provide peaking and load-following generation. Its ability to provide such benefits and meet other flow-related needs is largely dependent on the schedule of flows being released from upstream reservoirs. Currently, an agreement between Alcoa Power Generating, Inc., Yadkin Division (APGI) and Progress Energy governs the release of waters from the APGI developments to the Progress Energy developments. The Project has been continuously operated since 1928, and has a total generating capacity of 108.6 MW. Operational characteristics of each development are listed in Table 3-1. It is operated to provide peaking, load-following, and system control services. Progress Energy operates the Project in coordination with flow releases provided by the upstream Yadkin Project. Daily operation of the two hydroelectric plants is managed to comply with reservoir level requirements based on inflows. In addition, Progress Energy is required by its FERC license to provide continuous releases from the Tillery and Blewett Falls Developments of no less than 40 and 150 cfs, respectively (Progress Energy 2003). The Project intakes vary as to their configuration and location with respect to the powerhouse and shorelines, their depth, and the clear spacing between bars of their structural steel trashracks (Table 2). The Tillery Dam created the impoundment known as Lake Tillery. At the normal maximum operating elevation of 277.3 ft, Lake Tillery is approximately 72-ft deep at the dam and has a reservoir surface area of approximately 5,697 acres1 (Table 3-2). The Blewett Falls Dam created Blewett Falls impoundment. The normal maximum pool elevation is 177.2 ft with an average depth of approximately 11 ft. The surface area of the lake at the normal maximum operating pool is approximately 2,866 acres (Table 3-2). An important consideration in any project entrainment study is the resident fish population thus, brief summaries of each of the impoundment’s fish populations are provided in addition to the respective physical characteristics. Each summary is related to a priority list of species that are either very abundant in the reservoir, or the focus of North Carolina Wildlife Resources Commission

1 Unless otherwise noted, all elevations are in NAVD 88 datum. NAVD 88 datum is 0.9 feet lower than 1929 NGVD

datum.

Section 3 Site Description

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Figure 3-1 Yadkin-Pee Dee River Project location map.


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Table 3-1 Summary of Tillery and Blewett Falls turbine-generator equipment and summary of turbines from EPRI (1997). Project Turbine Unit 1 Unit 2 Unit 3 Unit 4 Unit 5 Unit 6

Manufacturer I.P. Morris I.P. Morris I.P. Morris Allis-Chalmers J. Leffel N/A Type Vertical Francis Vertical Francis Vertical Francis Vertical Propeller Vertical Francis N/A Rated Power (hp) 31,100 25,600 31,100 33,000 650 N/A Rated Head (feet) 70 70 70 70 70 N/A Speed (rpm) 90 75 90 128.6 600 N/A Discharge Capacity (cfs) 4,456 3,627 4,456 5,145 100 N/A Number of runners per turbine 1 1 1 1 N/A Number of runner blades 22 22 22 5 N/A Runner inlet diameter (inches) 173 170 173 180.38 N/A Peripheral runner velocity (ft/sec) 67.95 55.63 67.95 101.21 N/A

Generator Manufacturer Allis-Chalmers Allis-Chalmers Allis-Chalmers Westinghouse Westinghouse N/A Rated p.f. 0.8 0.8 0.8 0.8 0.8 N/A

Tillery

Power rating (kW) 22,000 18,000 22,000 22,000 450 N/A Turbine

Manufacturer S. Morgan Smith S. Morgan Smith S. Morgan Smith S. Morgan Smith S. Morgan Smith S. Morgan Smith Type Horizontal Francis Horizontal Francis Horizontal Francis Horizontal Francis Horizontal Francis Horizontal Francis Rated Power (hp) 5,350 5,350 5,350 6,400 6,400 6,400 Rated Head (feet) 47 47 47 47 47 47 Speed (rpm) 164 164 164 160 160 160 Discharge Capacity (cfs) 1,351 1,351 1,351 1,715 1,715 1,715 Number of runners per turbine 4 4 4 4 4 4 Number of runner blades each/total 16/64 16/64 16/64 16/64 16/64 16/64

Runner inlet diameter (inches) 54 54 54 54 54 54 Peripheral runner velocity (ft/sec) 38.64 38.64 38.64 38.64 38.64 38.64

Generator Manufacturer General Electric General Electric General Electric General Electric General Electric General Electric Rated p.f. 0.8 0.8 0.8 0.75 0.75 0.75

Blewett Falls

Power Rating (kW) 3,200 3,200 3,200 5,000 5,000 5,000


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Table 3-2 Reservoir and intake characteristics of developments in the Yadkin-Pee Dee River Hydroelectric Project. Intake Depth Trashrack Bars

Project Surface Area at full pond

(acres)

Maximum and (mean)

reservoir depth (ft)

Normal Full Pond Elevation

(ft) Top (ft)

Center Line (ft)

Bottom (ft) Intake

Width1 (ft) Gross Area1 (sq ft)

Width (in)

Clear Spacing

(in)

Number of Units

Tillery 5,697 70.5 (23.6) 277.3 37.46 50.46 63.4 24 624 0.375 2.625 5 Blewett Falls 2,866 35.0 (10.8) 177.2 20 28.4 54 16 384 0.375 1.6875 6

1 Values per individual turbine.


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(NCWRC) management efforts. A river basin fisheries survey is under development by NCWRC and may be completed during 2005. The most recent, comprehensive fish sampling of the Project reservoirs were conducted by Progress Energy biologists from 1986 to 2002. The top seven species in each reservoir were considered the most abundant fishes in each reservoir at present and of most interest to NCWRC from the standpoint of potential entrainment losses. The Water RWG also requested that Progress Energy evaluate the potential effects of entrainment on five species of diadromous fish (hickory shad, blueback herring, American shad, American eel, shortnose sturgeon, and striped bass) that are potential future targets of a Yadkin-Pee Dee River Basin restoration plan. The restoration plan development is being guided by the U.S. Fish and Wildlife Service (USFWS) in cooperation with NCWRC and National Marine Fisheries Service (NMFS). A draft plan has been prepared which focuses on restoration of American shad and American eel to the Pee Dee River and tributaries between the Blewett Falls Dam and Tillery Dam as the first incremental step in restoration (USFWS et al. 2004). Eventually, the plan is expected to include proposed restoration activities at both project developments as well as the four Yadkin developments located upstream.

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Section 4 - Methods Fish entrainment has been the subject of more than 40 studies nationwide over the past 15 years (FERC 1995; EPRI 1997), including several studies in the Carolinas. Field studies typically sample fish from the flow of project turbines at regular intervals through the course of a year. These catch data are then extrapolated to un-sampled periods to estimate the number of fish that are entrained annually (EPRI 1997). A desktop entrainment and survival study typically involves a thorough review of published literature from field studies. Following the “Class of ’93” (a disproportionate number of FERC licensed project licenses expired in 1993), much of the available empirical information, including difficulties in conducting entrainment studies was collected and compiled by EPRI, and published in 1997 as a turbine entrainment and survival database. The EPRI process followed for this assessment of entrainment potential and turbine passage survival was: ■ Compile and summarizing life history information on all species of interest; ■ Characterize development sites; ■ Factors affecting entrainment potential at each project were qualitatively characterized as low,

medium, or high; and ■ The EPRI (1997) entrainment and survival database was referenced and species-specific

entrainment and survival rates were evaluated on a monthly and an annual scale. This desktop study follows the same methodology used in several recent hydropower relicensings in the southeast including the Catawba-Wateree Project (FERC No. 2232) and the Yadkin Project (FERC No. 2197), located immediately upstream of the Yadkin-Pee Dee River Project.

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Section 5 - Results and Discussions 5.1 Project Fisheries 5.1.1 Fish Populations and Species of Interest Lake Tillery supports a healthy warmwater sport fishery for largemouth bass, crappie, striped bass, white bass, white perch, catfish, and panfish (Lepomis spp.). Forty-three fish taxa were collected by Progress Energy biologists during the most recent fisheries studies conducted between 1986 and 2002 with most taxa represented by the sunfish (Centrarchidae), bullhead catfishes (Ictaluridae), and sucker (Catostomidae) families (Table 5-1). Gizzard shad, threadfin shad, white perch, bluegill, largemouth bass, redear sunfish, pumpkinseed, redbreast sunfish, white catfish, and yellow perch dominated the fish community in Lake Tillery during 2000. Among these numerically dominant species, NCWRC management interests are focused on largemouth bass, crappie, and striped bass. Although Blewett Falls Lake was dominated by a few species, the reservoir has a healthy and diverse fish community (Progress Energy 2003a and Table 5-1). In particular, native and nonnative planktivorous or benthivorous feeding fish species — bluegill, threadfin shad, blue catfish, and smallmouth buffalo — were very prevalent in the fish community. Fifty-six taxa were collected from the reservoir during 1999 and 2001 with Centrarchidae, Cyprinidae, and Catostomidae families representing most taxa (Progress Energy 2003). Species composition may have been influenced, to some extent, by fish movement to and from the river reach located above the reservoir. Species were selected for entrainment and survival evaluation based on their relative abundance in the Project area, importance in resource management plan objectives, and availability of existing information on entrainment and survival studies. The following target species were evaluated in this desktop study: ■ Gizzard shad (also serves as surrogate for American shad); ■ Threadfin shad; ■ American shad (for survival estimates only); ■ Largemouth bass; ■ Bluegill; ■ Black crappie; ■ Channel catfish (also serves as surrogate for blue catfish); ■ White catfish; ■ White perch; ■ White bass (used ad a surrogate for striped bass); ■ Redhorse (Moxostoma spp. used as surrogate for Carolina and robust redhorse); and ■ American eel. While life history characteristics are reviewed for shortnose and Atlantic sturgeon, there is no existing information (EPRI 1997) on entrainment or survival rates available and no suitable surrogate species.

Section 5 Results and Discussions

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Table 5-1 Fish taxa collected in the vicinity of the Yadkin-Pee Dee River Hydroelectric Project (Blewett Falls and Tillery Hydroelectric Developments) including Lake Tillery and Blewett Falls Lake, 1986-2002.

Common Name Scientific Name+ Lake Tillery Blewett Falls Lake Longnose gar Lepisosteus osseus X X American eel Anguilla rostrata X Blueback herring Alosa aestivalis X X Gizzard shad Dorosoma cepedianum X X Threadfin shad D. petenense X X Satinfin shiner Cyprinella analostana X Whitefin shiner C. nivea X Fieryblack shiner C. pyrrhomelas X Unknown Cyprinella Cyprinella spp. X Common carp Cyprinus carpio X 1 X Eastern silvery minnow Hybognathus regius X Bluehead chub Nocomis leptocephalus X Golden shiner Notemigonus crysoleucas X X Whitemouth shiner Notropis alborus X 2 Comely shiner N. amoenus X Spottail shiner N. hudsonius X X Taillight shiner N. maculatus X Unknown Notropis Notropis spp. X Quillback Carpiodes cyprinus X X Highfin carpsucker C. velifer X 1 White sucker Catostomus commersoni X Creek chubsucker Erimyzon oblongus X X Unknown Erimyzon Erimyzon spp. X X 2 Smallmouth buffalo Ictiobus bubalus X Spotted sucker Minytrema melanops X Silver redhorse Moxostoma anisurum X X Shorthead redhorse M. macrolepidotum X X Carolina redhorse Undescribed Moxostoma spp. X X Unknown Moxostoma Moxostoma spp. X 1 X Brassy jumprock Scartomyzon spp. X Snail bullhead Ameiurus brunneus X White catfish A. catus X X Yellow bullhead A. natalis X Brown bullhead A. nebulosus X X 1 Flat bullhead A. platycephalus X Unknown Ameiurus Ameiurus spp. X 3 Blue catfish Ictalurus furcatus X X Channel catfish I. punctatus X X Flathead catfish Pylodictis olivaris X X Redfin pickerel Esox americanus americanus X Chain pickerel Esox niger X Pirate perch Aphredoderus sayanus X Eastern mosquitofish Gambusia holbrooki X X


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Common Name Scientific Name+ Lake Tillery Blewett Falls Lake White perch Morone americana X X White bass M. chrysops X X Striped bass M. saxatilis X X Unknown Morone Morone spp. X 1 X Bluespotted sunfish Enneacanthus gloriosus X 2 Redbreast sunfish Lepomis auritus X X Green sunfish L. cyanellus X X Pumpkinseed L. gibbosus X X Warmouth L. gulosus X X Bluegill L. macrochirus X X Redear sunfish L. microlophus X X Hybrid sunfish Lepomis hybrid X X Unknown Lepomis Lepomis spp. X X 2 Largemouth bass Micropterus salmoides X X White crappie Pomoxis annularis X X Black crappie P. nigromaculatus X X Unknown Pomoxis Pomoxis spp. X Tessellated darter Etheostoma olmstedi X X Unknown Etheostoma Etheostoma spp. X X Yellow perch Perca flavescens X X Total number of taxa 43 56

+Taxonomic nomenclature follows Robins et al. (1991) except for brassy jumprock (Scartomyzon spp.), Carolina redhorse (undescribed Moxostoma spp.), and robust redhorse (Moxostoma robustum). Species in bold non-native to the Yadkin-Pee Dee watershed. 1 Only collected in 1986. 2 Only collected in 1993. 3 Only collected in 1992. 5.1.2 Fisheries Management History and Goals Fishery management studies conducted by the NCWRC on Lake Tillery and Blewett Falls Lake since the 1960s have primarily assessed the largemouth bass and crappie populations (Tatum 1960; Van Horn et al. 1981, 1986; Chapman 1983; Van Horn and Jones 1990 as cited by Progress Energy 2003; Harland 2004a, 2004b). These studies were primarily designed to determine abundance, size, and age structure, young-of-year recruitment, and relative body condition of these sport fishes as related to harvest by anglers. Other fishery management activities have focused on the development of white bass fisheries within the reservoir-tailwater systems and a put-grow-and-take stocking program to develop striped bass fisheries within both reservoirs. The NCWRC published The North Carolina Black Bass Management Plan during 1993. This plan provides direction for managing largemouth bass populations throughout the state, including the Project reservoirs (NCWRC 1993 as cited by Progress Energy 2003). Several strategies were outlined in the plan, most notably habitat protection, angler creel restrictions to manage age and size structure, angler use feedback on management strategies, and management of fish stocking activities in reservoirs that is compatible with the plan’s objectives. During the spring (April 15 to May 15),


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Progress Energy has a voluntary agreement with the NCWRC to hold the lake elevation of Lake Tillery as constant as practicable during the largemouth bass spawning season (1 ft below lake full-pool elevation). The NCWRC has also regulated angler harvest of crappie populations in Lake Tillery and Blewett Falls Lake, with a size restriction of 8 inches and a 20-fish-per-day creel limit. This regulation was implemented during July 1991. The management goal of this regulation is to maintain quality crappie populations in the reservoirs. Recent studies by NCWRC (Harland 2004a, 2004b) indicate that black crappie populations are healthy in both impoundments, based on fishery assessments. NCWRC is in the process of updating its Fish and Wildlife Management Plan for the Yadkin-Pee Dee Basin. The updated management plan is currently in draft form (Dorsey et al. 2004). The new draft plan also indicates that the Yadkin-Pee Dee chain of lakes generally support good populations of largemouth bass, crappie, striped bass, and catfish. The continued management, regulation, and enhancement of striped bass, largemouth bass, crappie, catfish, and sunfish are management goals for both Lake Tillery and Blewett Falls Lake (Dorsey et al. 2004). Management of diadromous fish species (American eel, American shad, Atlantic sturgeon, shortnose sturgeon, blueback herring, and striped bass) in North and South Carolina is under jurisdiction of the National Marine Fisheries Service (NMFS) and the Atlantic States Marine Fisheries Commission (Beal et al. 2000; Stirratt et al. 1999, 2000a, 2000b; NMFS 2004). The South Carolina Department of Natural Resources (SCDNR) and NCWRC regulate harvest of migratory and resident warmwater fish species in the Pee Dee River below the Blewett Falls Development. Recreational harvest of American shad and striped bass in the Pee Dee River waters is permitted in North Carolina. A creel limit of 10 fish per day with no size restrictions for American shad. Creel limits for striped bass are three fish per day and at least 18 inches in total length within North Carolina waters, while South Carolina permits a recreational harvest of 10 striped bass per day with no size restrictions. No harvest of Atlantic or shortnose sturgeon is permitted in either state. A recovery plan has been prepared by the NMFS for shortnose sturgeon, a federally-listed endangered species (NMFS 1998a). The plan outlines several steps for recovery of this species, which includes establishing listing criteria for specific river populations and protection and restoration of populations and habitat respective to key life stage requirements. A joint plan for the restoration of diadromous fishes of the Yadkin-Pee Dee River outlined the several issues as significant obstacles to the restoration of diadromous fishes. The plan also outlined a sequential approach to restoring riverine habitats and for providing safe and effective fish passage (USFWS et al. 2004). The primary species to benefit from this plan are American shad and American eel. Current population targets for the restoration of American shad are 50 fish/acre of suitable riverine habitat (USFWS et al. 2004).


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5.1.3 Characteristics of Selected Species ■ Clupeids (shad and river herring) Gizzard shad and threadfin shad are highly prolific pelagic species that represent the primary components of a rich forage base within all the Yadkin-Pee Dee River impoundments (APGI 2002; Progress Energy 2003). Each is a schooling species typically found in the upper 45 ft of the water column. Gizzard shad and threadfin shad will typically spawn throughout spring and summer in inshore areas, tributary coves, and in open water. Significant mortality of threadfin shad occurs as waters cool below 45°F (7°C) (Jenkins and Burkhead 1993). Threadfin shad are non-native to the Yadkin-Pee Dee River and have been stocked by NCWRC as an additional prey species for crappies, largemouth bass and striped bass. Gizzard shad are more cold tolerant, but will succumb or become moribund at prolonged water temperatures below about 3°F (37°C). Young gizzard and threadfin shad may emigrate from the reservoirs during fall and early winter as water temperatures cool. The tendency for both species to become moribund as their lower temperature threshold is approached (Rohde et al. 1994) furthers their susceptibility to entrainment. As a result, fall/winter shad entrainment peaks are typical in reservoirs where they are abundant (FERC 1995). Land-locked blueback herring have been recorded in the Tillery and Blewett Falls lakes. Land-locked populations of these species spawn in the reservoirs, tailwaters, headwaters, or tributaries. Pelagic schools of young or adults tend to seek warmer, deeper water in the lower reaches of the reservoirs as winter approaches. As a result of this behavior, schools can become proximal to reservoir outlets or turbine intakes and suffer entrainment losses. Large predators may also exit out of reservoirs following the schools of prey. At present, this land-locked form is not as abundant as threadfin or gizzard shad (APGI 2002; Progress Energy 2003). American and hickory shad were the only clupeids not represented among the source studies that comprised the EPRI (1997) database. If included in future Pee Dee River basin restoration plans, juvenile anadromous blueback herring, and American shad (alosids) represent potential pelagic forage species. Young-of-the-year fish that might be spawned in the reservoirs or in individual tributaries, tailwaters, or other riverine areas would leave freshwater rearing sites each fall to migrate to marine environments before returning to natal rivers several years later as adults. Thus, young anadromous alosids would be susceptible to entrainment at individual projects. Additionally, adult river herring return to marine waters after spawning and a proportion may survive to spawn in subsequent years. Entrainment of spent adults through project facilities could occur. Blueback herring are not included as a target restoration species in the USFWS et al. (2004) draft plan. Adult American shad south of Cape Hatteras typically die after the first spawn (Jenkins and Burkhead 1993), thus entrainment of spent adult American shad would not be a concern in the Project. American shad entrainment potential is not represented in the EPRI (1997) entrainment database but is evaluated through the surrogate gizzard shad. EPRI data was available to evaluate survival potential of American shad. ■ Centrarchids (largemouth bass, black crappie and bluegill) Three species of centrarchids (largemouth bass, black crappie and bluegill) were typically found among the Project reservoir species with the highest relative abundance. Bluegill represented the most abundant panfish sampled in the 1999 to 2001 reservoir studies. Largemouth bass and black


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crappie were also among the most abundant species throughout project waters. All three species are important to the recreational fishery in each reservoir. Bluegill, black crappie and largemouth bass, primarily inhabit littoral areas and orient to cover such as woody debris and aquatic vegetation. Largemouth bass and black crappie are highly fecund spring spawner that builds nests on the different substrates found in the littoral zone while bluegill are also highly fecund, they may spawn multiple times within a year. Young largemouth bass school early while guarded by a parent, and then disperse throughout the littoral zone. After spawning, largemouth bass may move about within a variable sized home range in summer. Where sunfish and crappie abundance in a reservoir is high, smaller individuals (young-of-year and juveniles) tend to form a large portion of the fishes entrained (FERC 1995). Bluegill, black crappie, and largemouth bass were each represented by at least 30 source studies in EPRI (1997). ■ Ictalurids (catfish) Channel, blue, and white catfish are abundant species in both the Tillery and Blewett Falls Lakes and targeted by anglers. Recreational anglers seek catfishes in both project reservoirs and tailwater reaches (Crochet and Black 1997 as cited by Progress Energy 2003) and the popularity of this fishery is enhanced by the large size attained (Chapman and Van Horn 1992 as cited by Progress Energy 2003). Channel, white, and blue catfish spawn after water temperatures attain 70°F (21°C) in spring and build sheltered nests or nests associated with cover (Jenkins and Burkhead1993). Eggs and larvae are brooded by the male, and parental care is extended to young by white catfish. Young disperse from schools to available habitats when about 1 inch (25 mm) long (Becker 1983). FERC (1995) noted the tendency for channel catfish relative abundance in entrainment samples to generally exceed their relative abundance in impoundment populations. No comparable data were available for blue or white catfish. Channel and white catfish are represented in the source studies for the EPRI (1997) database. Channel catfish were used as a surrogate species for blue catfish given the similar life history characteristics. ■ Moronids (temperate basses) White perch, white bass, and striped bass represent this family in the Project reservoirs. White perch comprised 78 percent of the gill net catch by number in Lake Tillery, while they comprised less than 10 percent by number in Blewett Falls Lake during the 1999 to 2001 sampling (Tables 5-2 and 5-3). White perch, white bass, and striped bass are pelagic piscivorous predators that typically forage in open water but may also be found in littoral areas. However, they are less cover-oriented than other littoral fishes such as centrarchids. Littoral areas may be occupied by white perch at night and during crepuscular periods, and more open waters during daytime. Their vertical distribution within a reservoir can be dependent on the depth of available prey. Further, white perch, white bass, and striped bass could be susceptible to fall and winter entrainment due to pursuit of clupeid schools to deeper water. The summer distribution of large striped bass in southern reservoirs may also depend on the availability of deep, oxygenated, cool water 72°F (


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Table 5-2 Mean number and weight (Kg) per 24 hours for fish collected with quarterly gill netting from Tillery Lake during 2000.

Transect B F H K

Reservoir Mean Taxon

No./24 hrs

Kg/ 24 hrs

No./24 hrs

Kg/ 24 hrs

No./24 hrs

Kg/ 24 hrs

No./24 hrs

Kg/ 24 hrs

No./24 hrs

Kg/ 24 hrs

Black crappie 0.9 0.2 1.3 0.3 0.2 0.1 0 0 0.6 0.2 Blue catfish 0.5 0.5 1 0.9 0.3 0.2 0.3 0.4 0.5 0.5 Blueback herring 0.4 < 0.1 0.1 < 0.1 0.8 < 0.1 0.1 < 0.1 0.4 < 0.1 Bluegill 0.1 < 0.1 0 0 0 0 0 0 < 0.1 < 0.1 Brassy jumprock 0 0 0 0 0.2 0.2 0.9 1 0.3 0.3 Brown bullhead 0.1 < 0.1 0.1 < 0.1 0 0 0 0 < 0.1 < 0.1 Channel catfish 0.2 0.2 0.1 0.1 0.7 0.7 0.5 0.5 0.4 0.4 Creek chubsucker 0.1 < 0.1 0 0 0 0 0 0 < 0.1 < 0.1 Flat bullhead 0.4 0.1 0 0 0 0 0 0 0.1 < 0.1 Flathead catfish 0 0 0.1 0.3 0.1 0.1 0 0 < 0.1 0.1 Gizzard shad 3.9 1.4 2.8 1.1 4.2 1.8 1.4 0.7 3.1 1.3 Largemouth bass 2.1 0.8 0.6 0.3 0.8 0.4 0.1 < 0.1 0.9 0.4 Lepomis hybrid 0.1 < 0.1 0 0 0 0 0 0 < 0.1 < 0.1 Longnose gar 0.2 0.3 0.1 0.3 1.7 3.2 0.2 0.4 0.5 1.1 Pumpkinseed 0.2 < 0.1 0.1 < 0.1 0.1 < 0.1 0 0 0.1 < 0.1 Quillback 0.1 0.1 0 0 0.1 < 0.1 0 0 < 0.1 < 0.1 Redbreast sunfish 0.1 < 0.1 0 0 0 0 0.1 < 0.1 < 0.1 < 0.1 Redear sunfish 0 0 0 0 0.8 0.1 0.2 < 0.1 0.3 < 0.1 Shorthead redhorse 0.1 0.1 0.1 < 0.1 0 0 0.9 0.9 0.3 0.2 Silver redhorse 0 0 0.1 0.1 0.4 0.5 0.1 0.1 0.2 0.2 Snail bullhead 0.1 0.1 0.1 < 0.1 0 0 0.7 0.2 0.2 0.1 Striped bass 0.7 0.9 0.5 0.5 0.7 0.3 0 0 0.5 0.4 Threadfin shad 0.2 < 0.1 0 0 0.7 < 0.1 0.2 < 0.1 0.3 < 0.1 Warmouth 0.5 < 0.1 0 0 0.1 < 0.1 0 0 0.2 < 0.1 White bass 0.3 0.1 0.2 0.1 0.4 0.2 0 0 0.2 0.1 White catfish 3.5 1.3 1.8 0.6 0.9 0.5 0.9 0.3 1.8 0.7 White crappie 0 0 0.1 < 0.1 0 0 0 0 < 0.1 < 0.1 White perch 38.7 5.8 57.1 8.2 48.1 7 7.9 1.1 37.9 5.5 White sucker 0 0 0 0 0 0 0.1 0.1 < 0.1 < 0.1 Yellow perch 0.1 < 0.1 0.2 < 0.1 0.2 < 0.1 0 0 0.1 < 0.1 Total 53.4 12 66.3 13 61.5 15.5 14.4 5.9 48.9 11.6

Source: Progress Energy 2003.


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Table 5-3 Mean number and weight (Kg) per 24 hours for fish collected with quarterly gill netting from Blewett Falls Lake during 2001.

Transect B D F H

Reservoir Mean Taxon

No./24 hrs

Kg/ 24 hrs

No./24 hrs

Kg/ 24 hrs

No./24 hrs

Kg/ 24 hrs

No./24 hrs

Kg/ 24 hrs

No./24 hrs

Kg/ 24 hrs

Black crappie 3.8 0.8 8.7 2.4 1.9 0.5 0 0 3.6 1 Blue catfish 13.1 3.4 11.8 3.9 25 4 2.1 2 13 3.3 Bluegill 0.3 < 0.1 0.2 < 0.1 0.2 < 0.1 0.1 < 0.1 0.2 < 0.1 Channel catfish 0.7 0.2 1.1 0.5 1.2 0.7 0.9 0.7 0.9 0.5 Common carp < 0.1 < 0.1 0 0 0.2 0.6 0 0 0.1 0.2 Eastern silvery minnow 0 0 0.1 < 0.1 0 0 0 0 < 0.1 < 0.1 Flathead catfish 0.2 0.4 0.2 0.3 0.3 0.5 0.2 0.2 0.2 0.4 Gizzard shad 1.8 0.1 1.1 0.1 1.6 0.3 2.5 0.5 1.8 0.3 Golden shiner 0 0 0.1 < 0.1 0.4 < 0.1 0 0 0.1 < 0.1 Largemouth bass 0.5 0.2 0.4 0.1 0.1 < 0.1 0 0 0.3 0.1 Longnose gar 0.1 0.1 0 0 0.5 0.8 1.1 2.5 0.4 0.9 Morone spp. 0 0 < 0.1 < 0.1 0 0 0 0 < 0.1 < 0.1 Pomoxis spp. 0 0 0 0 0 0 0.1 < 0.1 < 0.1 < 0.1 Redear sunfish 0 0 0 0 0.2 < 0.1 0.1 < 0.1 0.1 < 0.1 Shorthead redhorse 0 0 0.1 < 0.1 0 0 0 0 < 0.1 < 0.1 Smallmouth buffalo 0.6 0.6 2.1 1 0.6 0.5 0.8 0.8 1 0.7 Threadfin shad 37.2 0.3 82 0.8 42 0.4 1.6 < 0.1 40.8 0.4 Warmouth 0.2 < 0.1 0.3 < 0.1 0.1 < 0.1 0 0 0.2 < 0.1 White bass 0.4 0.2 0.2 0.1 0.1 < 0.1 0.6 0.4 0.3 0.2 White crappie 0.3 < 0.1 0.3 0.1 0.3 < 0.1 0 0 0.2 < 0.1 White perch 1.9 0.1 5.7 0.6 1.1 < 0.1 0.2 < 0.1 2.2 0.2 Yellow perch < 0.1 < 0.1 0 0 0.1 < 0.1 0 0 < 0.1 < 0.1 Total 61.2 6.5 114.3 10.2 75.9 8.5 10 7.1 65.4 8.1

Source: Progress Energy 2003.


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Semi-anadromous white perch typically move upstream within estuaries to spawn in spring (Jenkins 1993). However, land-locked white perch spawning in Nebraska reservoirs concentrated in shallow shoreline areas around the entire reservoir perimeter (Zuerlein 1981 as cited by Progress Energy 2003). By summer, young-of-the-year 1.5 to 2 inches (40 to 50 millimeters [mm]) long inhabited the same shallow littoral areas. White perch and white bass are well represented in the EPRI (1997) database. White bass was used as a surrogate for striped bass due to the limited information in the EPRI (1997) database. ■ Moxostomid (Redhorse) The robust and Carolina redhorse are rare species of concern which have been recently collected in waters associated with the Project developments. The Carolina redhorse currently is considered an undescribed sucker species. The undescribed status means established professional scientific committees have not officially validated the fish as a formal, distinct species through peer-review of its taxonomic and genetic characteristics. Neither of these species holds a legally protected (rare, threatened, and endangered [RTE]) status in North or South Carolina. However, both species are listed as federal species of concern (LeGrand et al. 2004). Redhorse tend to spawn in mid- to late spring, when water temperatures range from 50 to 72.5°F (10 to 22.5ºC). Spawning often occurs over gravel beds associated with shallow runs and riffles (Jenkins and Burkhead 1993). Juvenile and adult moxostomids occupy a broad range of warmwater habitats, for example large creeks, big rivers, natural lakes, and impoundments. These species feed on aquatic insects, small crustaceans, mollusks, algae and detritus, which are typically found in littoral habitats. Currently, robust redhorse has been found only in the Pee Dee River below the Blewett Falls Development, while Carolina redhorse is found both upstream and downstream of the Blewett Falls Dam and within the Little River associated with the Project boundaries. Additionally, one Carolina redhorse was been documented in Lake Tillery (Progress Energy 2003a). The EPRI (1997) database evaluated multiple moxostoma species, and this data was combined for this entrainment evaluation. ■ American eel The American eel has not been found in Lake Tillery and represented a very small percentage of the Blewett Falls Lake fish community. However, within the Pee Dee River below the Blewett Falls Development, American eels are relatively abundant. Despite their relatively low abundance and absence from the Project impoundments, the American eel has been included in this analysis because they are included in current draft planning documents for river basin restoration of diadromous fish. Atlantic Coast eel populations, including those in the Pee Dee River drainage, are currently managed by an Interstate Fisheries Management Plan for American eel (Atlantic States Marine Fisheries Commission [ASMFC] 2000). The American eel is catadromous, spawning in the Sargasso Sea and rearing and maturing in estuaries and a variety of freshwater riverine and lacustrine habitats. Some juvenile eels move beyond estuaries upriver into rearing habitats as elvers (


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more) and attain large size, exceeding 1 m or more in length. Large individuals that attain the furthest upriver habitats are typically females. A restoration scenario that provides passage or transport of young eels past project dams would ultimately put large female eels approaching maturation at risk of injury or mortality due to turbine entrainment as obligatory downstream migrants. There is some limited information on American eel in the EPRI (1997) database. ■ Acipenseridae (Atlantic and shortnose sturgeon) Atlantic and shortnose sturgeon, while historically present in the vicinity of Blewett Falls Dam, are currently absent from project waters, but may be included in future planning documents for river basin restoration of diadromous fish. However, there have been recent sightings and validation of Atlantic and shortnose sturgeon populations in South Carolina waters of the lower Pee Dee River below Blewett Falls Lake (Progress Energy 2003; Collins et al. 2003). Both the shortnose sturgeon, a state- (North South Carolina) and federally-listed endangered species, and the Atlantic sturgeon, a species of state and federal concern are managed by the NMFS (NMFS 1998a, 1998b, 2004). Sturgeon are a primitive group of fishes with cartilaginous skeletons and rows of bony plate in place of scales. They have a heterocercal tail and a protrusible ventral mouth adapted to benthic feeding of invertebrates (Hartel et al. 2002). Sturgeon are relatively long lived (30 to 60 years) but slow maturing species, which may not spawn until 10 years of age (Hartel et al. 2002). The Atlantic sturgeon is a closely related species to the shortnose sturgeon. The two species can be separated by several morphological characteristics when young and by size in older individuals. The Atlantic sturgeon can grow to 5.9 to 8.6 ft (1.8 to 2.6 m) in length, whereas adult shortnose sturgeon rarely exceed 4.5 ft (1.4 m) (Hartel et al. 2002). Sturgeon generally move upstream to spawn in the spring, under conditions of decreasing flow and water temperatures increasing from 48 to 57°F (9 to 14°C) (Kieffer and Kynard 1996). However, there is some evidence from the Pee Dee River to suggest a fall spawning segment of the population of Atlantic sturgeon may be present. Spawning habitat is described as main channel waters 5.9 to 18 ft (1.8 to 5.5 m) deep, water velocities from 1.0 to 2.3 fps (0.3 to 0.7 m/s), over cobble and boulder substrate (Kieffer and Kynard 1996). Following spawning, adults move downstream to a feeding area. Atlantic sturgeon spend less time in freshwater riverine habitats and do not ascend rivers as far as shortnose sturgeon. Atlantic and shortnose sturgeon were not examined in the EPRI (1997) database, and no suitable surrogate was available so these species were excluded from further detailed evaluation. 5.2 Entrainment and Survival Potential 5.2.1 Factors Affecting Fish Entrainment Abundance The size and number of fish entrained at a hydroelectric development is related to a variety of physical factors near the dam and powerhouse, such as plant flow, intake and forebay configuration, intake depth, intake approach velocities, trashrack spacing, plant operating mode, proximity to fish feeding and rearing habitats, and reservoir temperature and dissolved oxygen (DO) stratification patterns (EPRI 1992; FERC 1995). In conjunction with physical factors, biotic factors also


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influence a species susceptibility to entrainment. These variables include diurnal and/or seasonal movement patterns, fish size, swimming speed, fish behavior, relative population size, life history requirements, and density dependent influences (EPRI 1992; FERC 1995). 5.2.1.1 Relative Entrainment Potential One form of entrainment assessment does not employ the EPRI database, but looks at overall entrainment potential based on documented relationships to the physical features of the hydropower site, including general powerhouse and intake layout, generation equipment, and reservoir physical and biological characteristics. This type of assessment is a qualitative screening, and is effective for comparison of entrainment potential between two or more developments. Both the Tillery and Blewett Falls Developments were compared with respect to entrainment potential as they relate to fish species identified as target species in Section 5.1.1. The assessment examined individual characteristics associated with the dams, intakes, hydroplant structural elements, reservoir characteristics, and fish populations that can affect entrainment. Various comprehensive reviews of entrainment and mortality data (FERC 1995; EPRI 1997) as well as fish behavior relative to turbine passage (Coutant and Whitney 2000) suggest that one or more of the factors listed in Table 5-4 may influence the risk of turbine passage entrainment or mortality. Among factors that can influence entrainment rates, this assessment examined the following: ■ Forebay configuration - Nearshore intakes typically entrain fishes at higher rates than

offshore intakes, as fish tend to follow shorelines or orient to physical structure associated with shorelines.

■ Abundant littoral zone species - Fishes such as centrarchids that spawn, rear, and spend most of their lives in shallow nearshore waters tend to be among the most abundant species in a fish assemblage.

■ Abundant limnetic zone species - Entrainment rates trend highest at projects with clupeids such as gizzard shad and threadfin shad.

■ Intake depth - Fish are usually more abundant in shallower portions of a reservoir throughout most of the year.

■ Hydraulic capacity - More water passed through intakes will entrain more fish for a given entrainment rate.

■ Annual plant factor - The plant factor is a ratio of mean annual output of a power station to its maximum annual output if it were to operate at full capacity for the entire year. Therefore, if a project operates at less than maximum, it will not entrain as many fish.

Each reservoir was examined individually with respect to these multi-metric indices. This approach borrowed metric scoring concepts from widely used and accepted rapid bioassessment protocols such as the Index of Biotic Integrity used to characterize water resource conditions (Karr et al. 1986; Barbour et al. 1999). These indices differ from the biotic indices cited previously in that all scoring was relative between developments. Scoring was not based on any reference condition or standard, and therefore do not represent a quantitative assessment of potential impact, but rather a relative ranking between developments, following the methods of GeoSyntec (2004). Therefore, scores derived in this study should not be compared to other hydroelectric projects.


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Each metric was subjectively assigned a score of 1, 3 or 5, with lower values assigned to features with less impact or potential for entrainment (Tables 3-1, 3-2, and 5-4). Weighted averages were used to evaluate metrics with multiple values at a single project (turbine speed, number of runner blades, rated flow, runner inlet diameter, and peripheral runner velocity). Metrics with similar characteristics at other projects were scored similarly in this analysis (GeoSyntec 2004). Table 5-4 Metric scoring for indices of relative entrainment potential for Yadkin-Pee

Dee River Hydroelectric Developments (after GeoSyntec 2004). Metric Tillery Blewett Falls Entrainment potential Forebay configuration 1 5 Depth of intake 3 5 Total hydraulic capacity 5 3 Annual plant factor 3 5 Littoral fish density 3 5 Limnetic fish density 3 5 Total Score1 (Moderate) 18 (High) 28

1 Low - 6-10; Moderately Low - 11-15; Moderate - 16-20; Moderately High - 21-25; and High - 26-30. Future plans for the Pee Dee River basin may include restoration of anadromous alosids, American eel, and shortnose and Atlantic sturgeon to Project waters (USFWS et al. 2004). Juvenile anadromous blueback herring, American shad, and adult American eel represent obligatory migrants from freshwater systems to the ocean to complete their lifecycle. Whereas non-migratory fish entrainment may be viewed as accidental (Coutant and Whitney 2000), obligate migrants are subject to the effects of cumulative mortality when passing out of rivers with multiple hydro projects. This study included these species in the overall entrainment potential; however, it is important to note that the EPRI database does not distinguish between resident and obligate migratory species. The qualitative results of this evaluation are presented in Table 5-4. The overall entrainment potential of the Tillery development was rated “moderate”, while Blewett Falls was rated “high” principally based on the intake orientation and layout, abundance of clupeids throughout the system, as well as numerous and abundant centrarchid species, primarily Lepomis sunfish. Young gizzard and threadfin shad, as well as young bluegill and crappie, are typically the most abundant species entrained in reservoirs where they are abundant (FERC 1995). Entrainment of cluepeids tends to be episodic due to their schooling behavior and their susceptibility due to lethargy induced by cold water. These episodic events tend to occur most often during the fall and winter. Additionally, seasonal movement patterns of clupeids may result in an increased potential of entrainment of predatory species utilizing the clupeid forage base. 5.2.1.2 Entrainment Potential Utilizing EPRI Database To obtain an estimate of individual species and seasonal entrainment potential, the data provided in the EPRI database was reviewed. Entrainment densities and entrainment potential in Table 5-5 represent up to 39 developments per species in the database without regard to variations in local conditions (e.g., intake configuration, reservoir size, etc.) that may influence entrainment. However,


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these data have been standardized on a per-unit volume of water passed through each turbine (numbers per million cubic feet of water) to remove the effect of flow through the turbine. Further, not all species of management interest or concern within the Project area were represented in the EPRI (1997) database. Species of interest or concern not represented in the EPRI (1997) database were assigned a surrogate. Surrogates were assigned from the same taxonomic family and linked to species with similar life history and biological traits. Table 5-5 Average annual entrainment densities for Yadkin-Pee Dee River Project fish

species of interest from EPRI (1997) entrainment database. Annual density shown as fish per million cubic feet of water.

Mean Entrainment Rate (Number/106Cubic Feet) Species 15”

Gizzard shad1 61.8495 6.1041 0.7061 0.0001 Threadfin shad 3.0521 0.3653 0.0000 0.0000 Channel & blue catfish2 1.6751 0.0395 0.0183 0.0009 Black crappie 1.0853 0.0590 0.0135 0.0000 Bluegill 0.3036 0.0290 0.0028 0.0010 Blueback herring 0.2896 1.5445 0.0558 0.0000 Largemouth bass 0.1976 0.0340 0.0035 0.0005 White perch 0.0474 0.0256 0.0059 0.0000 White catfish 0.0232 0.0952 0.0146 0.0000 Moxostoma spp.3 0.0177 0.0124 0.0062 0.0014 White bass4 0.0038 0.0094 0.0299 0.0000 American eel 0.0000 0.0000 0.0170 0.0514

1 Also used as a surrogate for American shad. 2 Channel catfish entrainment rate are also applicable to blue catfish. 3 Moxostoma spp. was used to describe Carolina redhorse. 4 Used as a surrogate for striped bass. Small fish (15 inches) fish (Tables 5-6 through 5-11). In fact, most studies have shown that entrainment is highest for fish less than 4 inches (FERC 1995; Winchell et al. 2000). Table 5-6 Mean monthly entrainment densities of Clupeids from EPRI (1997)

database. Monthly density shown as fish per million cubic feet of water. Mean Entrainment Rate (Number/106 Cubic Feet) Month Species1


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Mean Entrainment Rate (Number/106 Cubic Feet) Month Species1


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Table 5-8 Mean monthly entrainment densities of centrarchids from EPRI (1997) database. Monthly density shown as fish per million cubic feet of water.

Mean Entrainment Rate (Number/106 Cubic Feet) Month Species


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Table 5-9 Mean monthly entrainment densities of moronids from EPRI (1997) database. Monthly density shown as fish per million cubic feet of water.

Mean Entrainment Rate (Number/106Cubic Feet) Month Species


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Table 5-11 Mean monthly entrainment densities of Moxostoma from EPRI (1997) database. Monthly density shown as fish per million cubic feet of water.

Mean Entrainment Rate (Number/106 CFS) Month Species 15"

January Moxostoma spp. 0.0088 0.0000 0.0064 0.0000 February Moxostoma spp. 0.1131 0.0051 0.0000 0.0000 March Moxostoma spp. 0.0033 0.0044 0.0000 0.0000 April Moxostoma spp. 0.0087 0.0010 0.0053 0.0004 May Moxostoma spp. 0.0067 0.0002 0.0169 0.0057 June Moxostoma spp. 0.0411 0.0027 0.0036 0.0016 July Moxostoma spp. 0.0137 0.0189 0.0097 0.0019 August Moxostoma spp. 0.0116 0.0023 0.0012 0.0006 September Moxostoma spp. 0.0126 0.0076 0.0019 0.0006 October Moxostoma spp. 0.0121 0.0637 0.0105 0.0000 November Moxostoma spp. 0.0093 0.0044 0.0008 0.0000 December Moxostoma spp. 0.0116 0.0054 0.0000 0.0000

EPRI (1997) developed a five-tier qualitative index of entrainment abundance from low to high based upon break points in entrainment abundance between different species and size categories. These qualitative categories are utilized in the discussions that follow describing entrainment potential. Small- and medium-sized clupeids generally have the highest potential for entrainment in reservoirs where they are abundant. Mean annual entrainment potential for small channel catfish and black crappie was also considered “high” based on the results from 41 sites (Table 5-5). Mean annual entrainment potential of small (


5-18

All other resident species are considered a low to moderate risk for entrainment, while each species displays a slightly elevated risk of entrainment at various times of the year. None of these species exhibit the same degree of increased susceptibility as the aforementioned species (Tables 5-9 through 5-11). Two factors that strongly influence entrainment abundance are not reflected in the discussion above. The first is at the Tillery Development, where the deeper turbine intakes are frequently below the thermocline during summer months where anoxic DO conditions exist (DO concentrations 2 mg/L). Since fish will actively avoid low DO water, it is expected that entrainment would be close to zero during summer months (June to September) when turbine intake DO is low. The second factor is at the Blewett Falls Development. Because the hydraulic capacity of the plant is low (9,200 cfs), flows in excess of 9,200 cfs will spill over the dam providing an alternative means of downstream passage, bypassing turbine entrainment. Spills occur most frequently in the spring (March to May) (Progress Energy 2003a). 5.2.1.3 Entrainment Effects on Diadromous Species In contrast to resident species, diadromous species which are currently proposed for restoration to Project waters between Blewett Falls and Tillery Dams are considered obligate migrants at one or more times in their life history. As a result, they are susceptible to turbine entrainment and mortality, absent an alternative passage option. Downstream passage typically reduces entrainment rates to 25 to 50 percent, compared to 100 percent entrainment when downstream passage is not provided for obligate migrants. While several diadromous species are mentioned and data is presented in this analysis, the EPRI (1997) database makes no distinction between resident and migrating population. Therefore, one can only assume that if a population is going to migrate then it would likely experience a higher potential of entrainment than indicated by the EPRI database, lacking other suitable downstream passage means. 5.2.2 Factors Affecting Turbine Survival/Mortality 5.2.2.1 Relative Entrainment Survival Potential Injury and mortality of fish that pass through hydroelectric turbines can occur by the following mechanisms (Cada 1990, 2001; Cada et al. 1997; and Odeh 1999): ■ Mechanical effects (strikes and grinding) - Direct strikes or collisions within the turbine

system, including moving runner blades fixed guides and stay vanes, etc. Grinding can occur when fish are drawn through narrow openings or gaps between fixed and moving structures in the turbine passageway. Additional mechanical effects include lacerations, descaling, decapitation, etc.

■ Pressure changes - Rapid and extreme pressure changes within the runner and draft tube. Water pressure within the turbine may increase to several times atmospheric pressure then drop to sub-atmospheric pressures. The primary cause of pressure-related mortality is related


5-19

to air bladder injury resultant from rapid pressure change (i.e., swim bladder distention or rupture).

■ Cavitation - The rapid formation of vapor bubbles caused by sub-atmospheric pressure within a turbine. Cavitation can occur downstream of the runner, in areas of increasing velocity, in areas with abruptly changing flow direction and along roughened or irregular surfaces.

■ Turbulence - Irregular movement of the water occurring throughout turbine passage. Intense small-scale turbulence can distort and compress portions of the fish’s body, while large-scale turbulence can spin and disorient fish leaving them susceptible to predation within the tailrace.

■ Shear stress - Fluid-induced forces applied parallel to the fish’s surface, experienced by a fish passing between two water masses of differing velocities, or sliding along a solid structure such as an intake wall or turbine blade. Shear stress can spin or deform entrained fish.

Survival of turbine-entrained fish depends on the physical characteristics of the turbine system, such as head, turbine size and design, runner speed, wicket gate openings, number of runner blades, runner blade angle, gap size, and water flow through the turbine (Cada 1990, 2001; Cada and Rinehart 2000). Many of these factors can cause mechanical injury. Therefore, survival depends on the species, size, physiology and behavior of entrained fish (Cada et al. 1997). Physiologically, physostomous fishes (fish with a pneumatic duct connecting the swim bladder to the esophagus, i.e., catfish, trout, and minnows) are better adapted to deal with the pressure changes within a turbine system than are physoclistous fish (fish lacking a pneumatic duct, i.e., bass, perch, and bluegill). Factors examined that can influence fish survival/mortality during turbine passage included: ■ Turbine type - Among factors related to passage survival, the size of water passage spaces

available relative to fish size influences susceptibility to contact with structural elements. Francis turbine runners have more closely-spaced buckets/blades than Kaplan/propeller runners; and thus spaces available for passage are smaller, particularly for larger-sized fish in Francis turbines.

■ Turbine speed - Higher revolutions per minute increase the likelihood of contact with structural elements.

■ Rated head - The greater the head the more elevated the risk of pressure-related mortality (Cada 1990).

■ Number of runner blades - The more blades a turbine has the more likely a fish is to be struck by one of those blades.

■ Rated flow - While hydraulic capacity is a primary determinant of entrainment potential, the higher the rate of flow the more fish could potentially be entrained. However, when assessing survival, high discharge rates tend to increase the portability of survival (Cada 1990).

■ Runner inlet clearance - The greater the clearance between the turbine and the turbine housing the more likely a fish will be able to enter and pass through the turbine with contact.

■ Peripheral runner velocity - Similarly to turbine speed, decreased peripheral runner velocity will increase the likelihood of survival by transmitting less force to a fish in the case of a blade strike.

Each development was examined individually with respect to these multi-metric indices to develop a relative index of entrainment survival independent of the EPRI database. The same methods were used to evaluate turbine survival as were used to evaluate entrainment potential (Table 5-4). The


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results of the qualitative assessment of relative entrainment survival are presented in Table 5-12. Both Tillery and Blewett Falls received the same “moderate” ranking for entrainment survival. Table 5-12 Metric scoring for indices of relative turbine mortality potential for Yadkin-

Pee Dee River hydroelectric developments (after GeoSyntec 2004). Turbine Mortality Potential Tillery Blewett Falls Rated head 3 1 Number of runner blades 3 5 Turbine operating speed2 3 3 Rated flow2 3 5 Runner inlet diameter 3 5 Peripheral runner velocity 3 1 Total Score1 (Moderate) 18 (Moderate) 20

1 Low - 6-10; Moderately Low - 11-15; Moderate - 16-20; Moderately High - 21-25; and High - 26-30. 2 Weighted averages from all turbines at each project were used for evaluating potential turbine mortality. 5.2.2.2 Entrainment Survival Utilizing EPRI Database. EPRI (1997) provides numeric probabilities of entrainment survival by species. Seventeen hydroelectric projects with Francis turbines were evaluated, and the range of turbine-generators evaluated are summarized in Table 5-13. Table 5-13 Summary of 17 Francis turbine-generators from EPRI (1997) database used

to estimate entrainment survival. Turbine Mean Minimum Maximum Power rating (kW) 5,290 900 14,950 Rated Head (feet) 71.8 17.3 258 Speed (rpm) 175.60 72 360 Discharge Capacity (cfs) 1,121 326 3,500 Number of runner blades 15.69 13 19 Runner inlet diameter (inches) 89.22 47.50 139

Francis Turbines

summarized from EPRI

(1997)

Peripheral runner velocity (ft/sec) 54.35 35.98 92.63

Survival data summarized from (EPRI 1997) and reported in Table 5-14 represent most of the Project reservoirs’ resident fish species of interest, including diadromous species considered for restoration. Operational characteristics of both Tillery and Blewett Falls Developments are within the ranges of the 17 hydroelectric projects evaluated in this study (compare Tables 3-1 and 5-13). Both immediate and 48-hour post-passage survival rates were used in this assessment. Mean survival rates are reported irrespective of local site conditions such as intake depth and tailrace configuration, which could affect ultimate fish survival during turbine passage. Recent studies by Franke et al. (1997) and Winchell et al. (2000) suggest that fish size is more important than species when assessing survival potential. However, the EPRI (1997) data is not presented in a format to allow for this, consequently survival rates are reported by species.


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Generally, immediate and 48-hour post-passage survival was moderate to high in all the studies evaluated in the EPRI (1997) report, although largemouth bass presented a unique situation. Largemouth bass exhibited a statistically significant greater likelihood of survival at discharges greater than 1,000 cfs (P=0.04 and 0.03, immediate and 48-hour post passage, respectively) (Table 5-14). Despite a significantly higher survival at higher discharges, mean probability of survival was still low, 72.7 percent immediately after passage and 58.7 percent 48 hours post passage (Table 5-12). No other evaluation species exhibited a significant difference in survival potential as a function discharge. Bluegill and Moxostoma spp. surrogates exhibited moderate survival immediately after passage (89.5 and 84.5 percent, respectively) and 48-hour post-turbine passage (86.5 and 83.0 percent, respectively) (Table 5-12). Table 5-14 Turbine passage survival estimates for Yadkin-Pee Dee River Project fish

species of interest from EPRI (1997) entrainment database. Mean Minimum Maximum Survival Potential2

Species N Immediate survival

48-hour survival

Immediate survival

48-hour survival

Immediate survival

48-hour survival

Immediate survival

48-hour survival

Blueback herring 1 0.967 0.943 0.967 0.943 0.967 0.943 High High Alewife 5 0.835 0.539 0.728 0.155 0.972 0.818 Moderate Low American eel 1 1.000 0.936 1.000 0.936 1.000 0.936 High High American shad 2 0.864 0.605 0.835 0.598 0.894 0.613 Moderate Low Bluegill 60 0.895 0.865 0.044 0.000 1.343 1.870 Moderate Moderate Catfish 8 0.995 0.979 0.962 0.885 1.000 1.087 High High Largemouth bass3 9 0.408 0.264 0.025 0.000 0.956 0.865 Low Low Largemouth bass4 13 0.727 0.587 0.073 0.045 0.956 0.865 Low Low White sucker 1 87 0.845 0.830 0.128 0.118 1.121 2.343 Moderate Moderate

1 White sucker was used as a surrogate for Moxostoma spp. 2 Qualitative survival rating: High = 90-100 percent; Moderate = 80-89.9 percent; Low


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through turbines, although it is generally accepted the injuries and injury-related mortalities are all associated with mechanical strikes (EPRI 2001). The entrainment survival assessment above takes the approach of combining data gathered from a broad range of turbine sizes (Table 5-13) to achieve large enough sample sizes to break-down survival by species. An alternative to this approach is presented by Winchell et al. (2000) where all species are combined. Winchell et al. (2000) noted that differences in fish size and turbine size, runner type, and speed had a greater influence on fish survival than fish species. Grouping the data in this fashion allows for much closer matching of project and database turbines and break-down by fish size. This also allowed data quality screening to use data only from tests where control fish survival was 90 percent or higher. All project turbines except the Tillery propeller unit are best represented by Winchell et al. (2000) grouping of Francis turbines under 250 rpm. This was also the most common turbine tested representing 11 to 19 different turbines. Mean survival based upon control survival screened data for Francis turbines under 250 rpm, from Winchell et al. (2000) are:

Fish Length Mean Immediate Survival (percent) Mean 48-hour Survival

(percent

6-1

Section 6 - Summary 6.1 Tillery Development The Tillery Development possesses several risk factors, suggesting entrainment rates are expected to be relatively moderate (Table 5-4). Entrainment potential is primarily influenced by high population densities of limnetic species such as clupeids and seasonally-high limnetic populations of white perch. Additionally, the Tillery Development exhibits moderate population densities of littoral fishes, including largemouth bass, bluegill, black crappie, and seasonally abundant populations of white bass, white perch, and juvenile ictalurids. The relatively shallow intake ceiling (37.46 ft below normal pool level) compared to other studies cited in EPRI (1997) also contributed to the assessment of a moderate risk of entrainment. Deep intake ceilings (e.g., >60 ft) are often isolated from areas of greater pelagic population densities, and therefore would have resulted in a lower score for this metric (Coutant and Whitney 2000). Additional variables factored into the assessment of this project include the moderate total hydraulic capacity, relatively moderate annual plant factor of 28.3 percent (based on 17 years of annual generation data, and intake placement relative to the littoral zone and shoreline (Tables 3-1, 3-2, and 5-4). While not included in the EPRI methodology for determining the entrainment risk potential of these projects, thermal and DO stratification patterns in Lake Tillery present a natural means of limiting entrainment potential. During periods of low DO and thermal stratification from May through September fish are often likely repelled from areas of low DO. Because Lake Tillery typically stratifies about 10 to 20 ft above the top of the intake, fish entrainment can be near zero when anoxic conditions exist at the intake. No single metric strongly influenced turbine survival positively or negatively. Based on the subjective rating system used in this analysis, the Tillery Development represents a moderate probability of survival for fish passing through the development powerhouse. Compared to the Blewett Falls Development which has 64 blades per turbine, Tillery has only 16, mean runner inlet clearance is over three times greater at Tillery, compared to Blewett Falls, and rated discharge per individual turbine is greater than four times that of Blewett Falls. The only metric that indicated greater mortality potential at Tillery than Blewett Falls was a moderate peripheral runner velocity of 73.2 ft/sec compared to 38.6 ft/sec at Blewett Falls. Overall entrainment survival at Tillery is expected to range between 85 to 95 percent (moderate to high) depending on fish species and size. 6.2 Blewett Falls Development The overall potential for fish entrainment at the Blewett Falls Development was judged to be high (Table 5-4). Entrainment risks at this development were strongly influenced by the forebay configuration (use of an intake canal), an annual plant factor of nearly 60 percent, a high population density of littoral and limnetic species such as clupeids, and seasonally-high limnetic populations of white perch. However, the small hydraulic capacity, and thus high frequency of spillage at Blewett Falls, helps mitigate this entrainment potential, especially during wet periods in spring and fall. Turbine survival was strongly influenced by virtually all metrics, leading to an overall evaluation of moderate. Metrics negatively affecting the survival evaluation included four runners per turbine with each runner having 16 blades, therefore 64 blades/turbine, relatively low discharge per turbine,

Section 6 Summary

6-2

and very small runner inlet diameter (Table 3-1). While these metrics lead to a decreased likelihood of survival, the relatively low head and slow peripheral runner velocity are metrics which are attributed to increased likelihood of survival (Tables 3-1 and 3-2). Comparable units in the EPRI database suggest entrainment survival should be in a similar range of 85 to 95 percent depending on fish size and species. 6.3 General Summary Based on current fish population data and resource management plans, the fish and populations are healthy in Lake Tillery and Blewett Falls Lake (Progress Energy 2003a). Overall entrainment potential estimates developed in this desktop evaluation were judged to be moderate to moderately high and turbine survival estimates were rated moderate to high for both developments. However, there is no evidence that entrainment at these projects is having a negative impact on the fishery resource at the population level. Generally, species that are most susceptible to entrainment (shad) are highly fecund fractional spawners. Fish biomass estimates for both Lake Tillery and Blewett Falls Lake are within expected ranges for southeastern impoundments of similar productivity.

7-1

Section 7 - References APGI. 2002. Yadkin Hydroelectric Project FERC No. 2197. Project Relicensing Initial

Consultation Document. September 2002. Alcoa Power Generating, Inc., Yadkin Division, Badin, NC.

Appalachian State University. 1999. North Carolina’s Central Park: Assessing Tourism and

Outdoor Recreation in the Uwharrie Lakes Region. Appalachian State University, September 1999.

Atlantic States Marine Fisheries Commission. 2000. Fishery Management Report No. 36 of the

Atlantic States Marine Fisheries Commission, Interstate Fishery Management Plan for American Eel (Anguilla rostrata). U.S. Department of Commerce, National Oceanic and Atmospheric Administration.

Barbour, M.T., J. Gerritsen, B.D. Snyder and J.B. Stribling. 1999. Rapid bioassessment protocols

for use in streams and wadeable rivers: periphyton benthic macroinvertebrates, and fish, second edition. EPA 841-B-99-002. U.S. Environmental Protection Agency, Office of Water, Washington D.C.

Beal, R., K. McKown, G. Shepard, and W. Laney. 2000. 2000 review of the Atlantic States Marine

Fisheries Commission fishery management plan for Atlantic striped bass (Morone saxatilis). Becker, G.C. 1983. Fishes of Wisconsin. The University of Wisconsin Press. Madison,

Wisconsin. Cada, G.F. 1990. A review of studies relating to the effects of propeller-type turbine passage on

fish early life stages. North American Journal of Fisheries Management 10:418-426. ——. 2001. The development of advanced hydroelectric turbines to improve fish passage survival.

Fisheries. 26(9):14-23. Cada, G.F., C.C. Coutant, and R.R. Whitney. 1997. Development of biological criteria for the

design of advanced hydropower turbines. DOE/ID-10578. Prepared for the U.S. Department of Energy, Idaho Operations Office, Idaho Falls, Idaho.

Cada, G.F., and B.N. Rinehart. 2000. Hydropower R&D: recent advances in turbine passage

technology. U.S. Department of Energy, Idaho Operations Office, DOE/ID-10753. April 2000.

Chapman, W.R. 1983. Trophy bass lakes. Performance Report F-23-S. North Carolina Wildlife

Resources Commission, Raleigh, North Carolina. Chapman, W.R. and S.L. Van Horn. 1992. Tuckertown Reservoir creel survey, 1988-1990. Final

Report. North Carolina Wildlife Resources Commission, Raleigh, North Carolina. Coutant, C.C. 1985. Striped bass, temperature and dissolved oxygen: a speculative hypothesis for

environmental risk. Trans. Amer. Fish Soc. 14:31-61.

Section 7 References

7-2

Coutant, C.C. and R.R. Whitney. 2000. Fish behavior in relation to passage through hydropower turbines: a review. Transactions of the American Fisheries Society 129:351-380.

Crochet, D.W. and W.P. Black. 1997. Fisheries investigations in lakes and streams. District VII.

Annual Progress Report F-31-9. July 1, 1996 to June 30, 1997. South Carolina Department of Natural Resources, Division of Wildlife and Freshwater Fisheries, Columbia, South Carolina.

Dorsey, L.G., K.B.Hodges, Jr., K.J. Hinning, and J.C. Borawa. 2004. Fisheries and Wildlife

Management Plan for the Yadkin-Pee Dee River Basin. North Carolina Wildlife Resources Commission. Draft Document.

Electric Power Research Institute. 1992. Fish entrainment and turbine mortality review and