kt-Updated-Study-Report-2014-01-24

KEOWEE- TOXAWAY HYDROELECTRIC PROJECT
FERC PROJECT NO. 2503
UPDATED STUDY REPORT
('DUKE
ENERGY
Prepared by:
Duke Energy Carolinas, LLC
Charlotte, North Carolina
January 2014
© Duke Energy Carolinas, LLC

Updated Study Report Keowee - Toxaway Hydroelectric Project
FERC No. 2503
TABLE OF CONTENTS
TERMS, ABBREVIATIONS, AND ACRONYMS ........... ............................... ............................
1.0 INTRODUCTION AND BACKGROUND ......................................... ............................... 1
1.1 Project Facilities ............................................................................... ............................... 2
1.2 Study Background ............................................................................ ............................... 4
1.3 Initial Study Report .......................................................................... ............................... 5
1.4 Updated Study Report ...................................................................... ............................... 6
1.4.1 Information on the Upcoming USR Meeting ............................. ............................... 6
1.5 Notice of Intent to File Draft License Application .......................... ............................... 6
2.0 STUDY SUMMARIES ........................................................................ ............................... 7
2.1
Fish Community Assessment Study ................................................ ............................... 8
2.2
Fish Community Assessment Study — Fish Entrainment Modification ..........................
9
2.3
Hydro Structures NRHP Eligibility Assessment Study ................... ............................... 9
2.4
Recreation Use and Needs Study ................................................... ...............................
10
2.5
Shoreline Erosion Study ................................................................ ...............................
10
2.6
Shoreline Classification Map Update Study .................................. ...............................
11
2.7
Lake Jocassee Forebay and Tailwater Water Quality Study ......... ...............................
11
2.8
Keowee Reservoir Water Quality Modeling Study ....................... ...............................
12
2.9
Reservoir Level and Project Flow Releases Study ........................ ...............................
13
2.10
Operations Model Study ................................................................ ...............................
13
2.11
Water Supply Study ....................................................................... ...............................
15
2.12
Wetlands Study .............................................................................. ...............................
16
2.13
Avian Study ................................................................................... ...............................
16
2.14
Mammal Study ............................................................................... ...............................
17
2.15
Botanical Study .............................................................................. ...............................
17
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APPENDICES
Keowee - Toxaway Hydroelectric Project
FERC No. 2503
APPENDIX A — ADDENDUM TO KEOWEE RESERVOIR WATER QUALITY MODELING
STUDY REPORT — W2 MODEL RESULTS COMPARING WATER
QUALITY PREDICTED UNDER DUKE ENERGY TRIAL BALLOON
(WQ3) AND REVISED (WQ4) OPERATIONAL CONDITIONS
APPENDIX B — ADDENDUM TO KEOWEE RESERVOIR WATER QUALITY MODELING
STUDY REPORT — W2 MODEL RESULTS FROM CLIMATE CHANGE
SCENARIOS USING 1998 AND 2008 DUKE ENERGY TRIAL BALLOON
(WQ3) CONDITIONS
APPENDIX C — ADDENDUM TO THE OPERATIONS MODEL STUDY REPORT
APPENDIX D — WATER SUPPLY STUDY REPORT ADDENDUM 2
LIST OF FIGURES
Figure 1 -1 Project Location Map ..................................................................... ............................... 3
LIST OF TABLES
Table 1 -1 FERC Approved and Modified Studies for the Project ................... ............................... 4
Table 2 -1 Final Study Report Submittal Dates ................................................ ............................... 7
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Keowee - Toxaway Hydroelectric Project
FERC No. 2503
TERMS, ABBREVIATIONS, AND ACRONYMS
AMSL
CFR
cfs
CHEOPSTM
DCP
DLA
DO
Duke Energy Carolinas
or Duke Energy
above mean sea level
Code of Federal Regulations
cubic feet per second
Computerized Hydro Electric Operations Planning
Software
Drought Contingency Plan
Draft License Application
Dissolved Oxygen
Duke Energy Carolinas, LLC, including all predecessor
companies
Existing License The license document as issued to Duke Energy for the
Keowee - Toxaway Hydroelectric Project (FERC Project
No. 2503) with an effective date of September 1, 1966, and
including all license amendments that have occurred since
that time. The Existing License is effectively a contract
between Duke Energy and the FERC that provides
requirements relative to Duke Energy's operation of the
Project through the license expiration date (i.e., September
1, 2016 unless extended by an annual license(s)).
FERC
Federal Energy Regulatory Commission
FERC Project Boundary The area surrounding hydro project facilities and features
as delineated in Exhibit G or originally Exhibit K of the
FERC license.
Forebay The reservoir area immediately upstream from the hydro
project powerhouse, from which water is drawn into a
tunnel or penstock for delivery to the powerhouse.
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FERC No. 2503
FPC Federal Power Commission, the predecessor to the FERC
ft foot / feet
g gram
GPD gallons per day
HEC ResSim Hydrologic Engineering Center's Reservoir System
Simulation
ILP
Integrated Licensing Process
ISR
Initial Study Report
KT
Keowee - Toxaway
L
Liter
LA/FLA
(Final) License Application
LRBR
Little River Bypassed Reach
M Meter
MW Megawatt
NC North Carolina
New License The license document that will be issued to Duke Energy
by the FERC to replace the Existing License and will
provide requirements relative to Duke Energy's operation
of the Project through the term of the New License,
including any extension periods for the New License as
may be granted by the FERC through annual licenses.
NGOs Non - Governmental Organizations
Normal Full Pond Elevation Also referred to simply as "full pond," this is the level of a
reservoir that corresponds to the point at which water
would first begin to spill from the reservoir dam(s) if Duke
Energy took no action. This level corresponds to the
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Updated Study Report Keowee - Toxaway Hydroelectric Project
FERC No. 2503
lowest point along the top of the floodgates. To avoid
confusion among the many reservoirs Duke Energy
operates, Duke Energy has adopted the practice of referring
to the Full Pond elevation for all of its reservoirs as equal to
100.0 ft relative or local datum.
NRHP National Register of Historic Places
OSC Operating Scenario Committee
ONS Oconee Nuclear Station
Penstock
An inclined pressurized pipe through which water flows
from a forebay or tunnel to the hydro powerhouse turbine
PLP
Preliminary Licensing Proposal
PM &E
Protection, Mitigation, and Enhancement measures
Project
Keowee - Toxaway Hydroelectric Project
PSP
Proposed Study Plan
Relicensing
The process of acquiring from FERC a new license for a
hydroelectric project that has an existing license
RSP
Revised Study Plan
RTE Rare, Threatened, and Endangered species
RUN Recreation Use and Needs
SC South Carolina
SCDNR South Carolina Department of Natural Resources
SERC SERC Reliability Corporation
SMP Shoreline Management Plan
Spillway A structure or passage for controlling high reservoir levels
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Updated Study Report Keowee - Toxaway Hydroelectric Project
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Stakeholder(s) Federal and state resource agencies, federally recognized
tribes, local governments, NGOs, and other interested
parties
Study Area The geographic area covered by a specific study typically
including the reservoir and any area within the zone of
operational influence
Tailrace Channel through which water is released from the hydro
powerhouse turbines
Tailwater The area immediately downstream of a hydro station
without a tailrace
Turbine A machine in a hydro station that converts the energy from
a stream of water into the mechanical energy of rotation;
this energy is then used to turn an electrical generator or
other device; also called a "water wheel" or "runner"
U.S.
United States
USACE U.S. Army Corps of Engineers
USFWS US Fish and Wildlife Service
USR
Updated Study Report
W2 CE- QUAL -W2; a hydrodynamic and transport water
quality model
Wetland Lands intermediate between aquatic and terrestrial
ecosystems where water is at, near, or above the land
surface long enough to be capable of supporting water
tolerant vegetation
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Updated Study Report Keowee - Toxaway Hydroelectric Project
FERC No. 2503
1.0 INTRODUCTION AND BACKGROUND
Duke Energy Carolinas, LLC (Duke Energy Carolinas or Duke Energy) is in the process of
applying for a New License from the Federal Energy Regulatory Commission (FERC or
Commission) to continue operation of the existing 867.6 megawatt (MW) Keowee - Toxaway
Hydroelectric Project (FERC No. 2503) (Project). The Project consists of two developments -
the Jocassee Development and the Keowee Development. The Project is located in Upstate
South Carolina primarily in Oconee County and Pickens County with a small portion of Lake
Jocassee extending into Transylvania County, North Carolina. Duke Energy is using the
Integrated Licensing Process (ILP), as outlined by FERC Regulations 18 CFR Part 5, to relicense
the Project.
The Project was issued an original license on September 1, 1966, by the Federal Power
Commission (FPC) (the FERC's predecessor agency). The Project's primary purposes include
hydroelectric and thermal electric generation. Other beneficial uses of the Project include
recreation and public water supply. The power generated by the Project helps meet the power
requirements of Duke Energy's service area and the SERC Reliability Corporation (SERC).
The 710.1 MW Jocassee Development is the upstream development of the Project and includes
the Jocassee Pumped Storage Station, Lake Jocassee, Jocassee Dam, and two saddle dikes. The
Jocassee Development is located on the Keowee River approximately 20 miles north of Seneca,
South Carolina. The Normal Full Pond Elevation is 1,110 feet above mean sea level (AMSL)
(see Figure 1 -1). At full pond, the reservoir has a surface area of approximately 7,980 acres with
approximately 92.4 miles of shoreline and a drainage area of 145 square miles.
Construction of the Jocassee Development began in 1968 and was completed in 1972.
Commercial operation of Units 1 and 2 began in 1973, and commercial operation of Units 3 and
4 began in 1975. The Jocassee Development releases water directly into Lake Keowee.
The 157.5 MW Keowee Development includes the Keowee Hydroelectric Station, Lake Keowee,
the Little River Dam, the Keowee Dam, and four saddle dikes. The Keowee Development is
located on the Keowee River approximately eight miles north of Seneca, South Carolina (see
Figure 1 -1). The Normal Full Pond Elevation is 800 feet AMSL. At full pond, the reservoir has
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Updated Study Report Keowee - Toxaway Hydroelectric Project
FERC No. 2503
a surface area of approximately 17,660 acres with 387.9 miles of shoreline and a drainage area of
435 square miles. Construction of the Keowee Development began in 1967 and was completed
in 1971. Commercial operation of the Keowee Development began in 1971. Water released
from Keowee Hydro Station flows directly into Hartwell Lake, a U.S. Army Corps of Engineers
(USACE) reservoir on the Savannah River.
In addition to the Project, two additional generating facilities utilize the Project reservoirs. The
Bad Creek Hydroelectric Project (FERC Project No. 2740) (Bad Creek Project) is a 1,065 MW
pumped storage station that utilizes Lake Jocassee as its lower reservoir. Oconee Nuclear
Station (ONS) is a 2,538 MW nuclear station that utilizes Lake Keowee as a cooling water
source and Keowee Hydro Station as a backup power supply.
1.1 Project Facilities
Jocassee
The Jocassee Development is located on the Keowee River in Oconee and Pickens Counties,
South Carolina and Transylvania County, North Carolina. The powerhouse is approximately 12
miles upstream of Keowee Hydro Station and approximately 5.5 miles northeast of Salem, South
Carolina. The Jocassee Development includes Lake Jocassee, the Jocassee Dam, two saddle
dikes (designated 1 and 2), two intake structures, water conveyance tunnels, the powerhouse, the
tailrace, and the gated spillway. Jocassee Pumped Storage Station generates electricity through
operations of four turbines that are supplied water through the two intake structures and tunnels
during peak demands, typically during the day, and pumps water from Lake Keowee back to
Lake Jocassee during low demand periods, typically at night. Lake Jocassee Normal Full Pond
Elevation is 1,110 ft AMSL with a minimum elevation for hydropower operations per the
Existing License of 1,080 ft AMSL.
Lake Jocassee also serves as the lower reservoir for the Bad Creek Project. When electricity is
being generated at the Bad Creek Project, water stored in the upper Bad Creek Reservoir is
released into Lake Jocassee through an underwater opening or discharge portal located on the
Whitewater River arm of Lake Jocassee. During the refilling of the upper Bad Creek Reservoir,
the pumped storage station turbines are reversed to pump water back from Lake Jocassee into the
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Updated Study Report
Figure 1 -1 Project Location Map
Keowee - Toxaway Hydroelectric Project
FERC No. 2503
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23
Kentucky Virginia
Legend
Keowee - Toxaway Relicensing
- -- Project Boundary 0 Lake
FERC Project Na. 2503
Tennessee
— County Boundary National Forest! Natural Area
North Carolina
— Stream 0 State Park / Natural Area
US Highway Urban Area
Project Location Map
South Carolina
Alabama Georgia
0 2 4 6 8
Data Saar
Base data deru.d from ESRI 9 3 Base Data. Layers, 7008
Project Location
Miles Prol"tion NAD 1983 StatePlana South Camlina International Feet
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Updated Study Report
Keowee - Toxaway Hydroelectric Project
FERC No. 2503
upper Bad Creek Reservoir. The Bad Creek Project began operations in 1991 and its FERC
license expires in 2027.
Keowee
The Keowee Development is located on the Keowee River which divides Oconee County from
Pickens County, South Carolina. The development consists of the Keowee Dam, Lake Keowee,
the Little River Dam, four saddle dikes designated A, B, C, D, the ONS intake dike, gated
concrete ogee spillway, the Keowee Powerhouse, and an intake structure. ONS lies just beyond
the right abutment of the Keowee Dam.
1.2 Study Background
The Existing License expires August 31, 2016, and Duke Energy is using the ILP as defined
under FERC Regulations (18 CFR Part 5) for relicensing. As required by 18 CFR §5.11, Duke
Energy prepared and filed a Proposed Study Plan (PSP) on August 26, 2011. Duke Energy held
the Initial PSP Meetings in accordance with 18 CFR §5.11(e) on September 13 and 14, 2011.
Agency recommendations obtained during these and other meetings and formal comments to the
FERC were integrated into the Revised Study Plan (RSP). The RSP was filed with the FERC on
December 22, 2011, and approved and modified per the Study Plan Determination Letter issued
by the FERC on January 27, 2012 (Table 1 -1).
Table 1 -1 FERC Approved and Modified Studies for the Project
11
Approved
Study
as Proposed
Approved
by Duke
With FERC
Energy
Modifications
Fish Community Assessment (FERC modification included a
X
Fish Entrainment Study)
Hydro Structures National Register of Historic Places (NRHP)
X
Eligibility Assessment
Recreation Use and Needs Study
X
Shoreline Erosion Study
X
Shoreline Classification Map Update
X
Lake Jocassee Forebay and Tailwater Water Quality Study
X
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Updated Study Report
Keowee - Toxaway Hydroelectric Project
FERC No. 2503
Study
Approved
as Proposed
by Duke
Energy
Approved
With FERC
Modifications
Keowee Reservoir Water Quality Model
X
Reservoir Level and Project Flow Releases Study
X
Operations Model
X
Water Supply Study
X
Wetlands Study
X
Avian Study
X
Mammal Study
X
Botanical Study
X
Fish Entrainment (included with Fish Community Assessment)
X
In 2012 and 2013, Duke Energy completed the FERC- approved studies detailed in the Study
Plan Determination Letter and submitted first season Study Progress Reports to the FERC on
June 15, 2012, and November 9, 2012. Duke Energy submitted the Initial Study Report (ISR) on
January 25, 2013, the ISR Meeting Summary on February 22, 2013, and second season Study
Progress Reports on April 29, 2013 and November 6, 2013.
1.3 Initial Study Report
The ISR filed with the FERC on January 25, 2013, provided a summary of all the FERC-
approved study plans (Table 1 -1) and included the following completed study reports.
• Fish Community Survey Report
• Hydro Structures NRHP Eligibility Assessment Report
• Shoreline Erosion Study Report
• Reservoir Level and Project Flow Releases Report
• Addendum to Operations Model Verification Report
• Water Supply Study Report
• Water Supply Study Report Addendum 1
• Wetlands Study Report
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Updated Study Report
1.4 Updated Study Report
Keowee - Toxaway Hydroelectric Project
FERC No. 2503
Section 2.0 of this Updated Study Report (USR) presents a discussion of study activities
performed in 2013 and an overall summary of the relicensing studies completed to date.
1.4.1 Information on the Upcoming USR Meeting
Pursuant to 18 CFR § §5.15(f) and (c)(2), within 15 days following the filing of the USR, the
potential applicant shall hold a meeting with stakeholders and FERC staff to discuss the study
results. On January 7, 2014, Duke Energy invited relicensing participants to attend the
upcoming USR Meeting. The USR meeting details are included below; those planning to attend
are asked to pre- register by emailing ktrelicensingkduke- energy.co by February 1, 2014.
Date:
Wednesday, February 5, 2014
Time:
9:00 am —1:00 pm
Location:
Duke Energy's Wenwood Operations Center
425 Fairforest Way
Greenville, South Carolina
Contact:
Ms. Elana Kimbrell
202 -535 -7800
Email:
ktrelicensinggduke- energy com
1.5 Notice of Intent to File Draft License Application
Pursuant to 18 CFR §5.16(a), Duke Energy is required to file a Preliminary Licensing Proposal
(PLP) no later than 150 days (April 3, 2014) prior to the deadline for filing a New License
application (August 31, 2014). Pursuant to 18 CFR §5.16(c), a potential applicant may elect to
file a Draft License Application (DLA), which includes the contents of a license application
required by 18 CFR §5.18, instead of the PLP. An applicant that elects to file a DLA must
include a notice of intent to do so in the USR required by §5.15(f) of the regulations. Duke
Energy herein includes its notice of intent to file a DLA in lieu of the PLP.
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Updated Study Report
2.0 STUDY SUMMARIES
Keowee - Toxaway Hydroelectric Project
FERC No. 2503
Duke Energy has completed the FERC- approved studies as required by the January 27, 2012
Study Plan Determination Letter. The final study reports have been submitted to the FERC for
all the studies, with the sole exception that the updated shoreline classification maps that are part
of the Shoreline Classification Map Update Study will be submitted with the Application for
New License. Study report addenda have also been filed with the FERC or are included with this
USR filing. A summary of the final study report submittal dates and study report addenda is
included in Table 2 -1 and an overall summary of the fourteen studies is provided below.
Table 2 -1 Final Study Report Submittal Dates
7
Final Study
FERC- Approved Studies
Report Submittal
Date
Fish Community Assessment Study
Fish Community Assessment Study Report
1/25/2013
Fish Community Assessment Study — Fish Entrainment
11/6/2013
Modification Report
Hydro Structures NRHP Eligibility Assessment Study
Hydro Structures NRHP Eligibility Assessment Study Report
1/25/2013
Recreation Use and Needs Study
Recreation Use and Needs Study Report
4/29/2013
Shoreline Erosion Study
Shoreline Erosion Study Report
1/25/2013
Shoreline Classification Map Update Study
Shoreline Classification Maps
License Application
Lake Jocassee Forebay and Tailwater Water Quality Study
Lake Jocassee Forebay and Tailwater Water Quality Study
2/22/2013
Report
Keowee Reservoir Water Quality Model Study
Keowee Reservoir Water Quality Model Study Report
4/29/2013
Keowee Reservoir Water Quality Model Study Report
Addendum — W2 Model Results Comparing Water Quality
USR*
Predicted Under Duke Energy Trial Balloon (WQ3) and Revised
(WQ4) Operational Conditions
Keowee Reservoir Water Quality Model Study Report
USR*
Addendum — W2 Model Results from Climate Change Scenarios
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Keowee - Toxaway Hydroelectric Project
FERC No. 2503
FERC- Approved Studies
Final Study
Report Submittal
Date
Using 1998 and 2008 Duke Energy Trial Balloon (WQ3)
Conditions
Reservoir Level and Project Flow Releases Study
Reservoir Level and Project Flow Releases Study Report
1/25/2013
Operations Model Study
Operations Model Verification Report
6/15/2012
Operations Model Verification Report Addendum
1/25/2013
Operations Model Study Report
4/29/2013
Operations Model Study Report Addendum
USR*
Water Supply Study
Water Supply Study Report
1/25/2013
Water Supply Study Addendum 1
1/25/2013
Water Supply Study Addendum 2
USR*
Wetlands Study
Wetlands Study Report
1/25/2013
Avian Study
Avian Study Report
2/22/2013
Mammal Study
Mammal Study Report
4/29/2013
Botanical Study
Botanical Study Report
2/22/2013
Revised Botanical Study Report
11/6/2013
*Included with this filing
2.1 Fish Community Assessment Study
FERC staff approved Duke Energy's proposed Fish Community Assessment Study Plan with
modifications to include an evaluation of fish entrainment as requested by the U.S. Fish and
Wildlife Service (USFWS), the South Carolina Department of Natural Resources (SCDNR), and
Upstate Forever. Duke Energy filed a study plan addendum to include and address the FERC-
required modifications (see Section 2.2).
The goal of the Fish Community Assessment Study was to collect additional information on
fishery resources from the Project area or areas immediately adjacent to the Project. Study
objectives from the FERC- approved study plan included: 1) collect and evaluate spring and
summer fish community data from the immediate tailwaters of Jocassee Pumped Storage Station
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Updated Study Report Keowee - Toxaway Hydroelectric Project
FERC No. 2503
and Keowee Hydro Station and from reference locations downstream of these facilities; and 2)
collect and evaluate fish community data from the Little River Bypassed Reach (LRBR).
The Fish Community Assessment Study was completed in 2012 and the final report was filed
with the ISR on January 25, 2013.
2.2 Fish Community Assessment Study — Fish Entrainment Modification
Pursuant to the January 27, 2012 Study Plan Determination Letter, FERC staff directed Duke
Energy to expand the scope of the Fish Community Assessment Study to address fish
entrainment. On June 15, 2012, Duke Energy filed an addendum to the study plan addressing the
study modification.
The primary goal of the Fish Entrainment Study was to determine the potential effects of
Jocassee Pumped Storage Station operations on the fisheries of both Lakes Keowee and
Jocassee.
Pursuant to the FERC- approved study plan addendum, Duke Energy conducted a 12 -month
study (July 2012 through June 2013) to estimate species, numbers, and sizes of fish entrained
during the generation and pumping modes of operation at the Jocassee Pumped Storage Station.
The Fish Entrainment Study was completed in 2013 and the final report was filed with the
November 6, 2013, Study Progress Report.
2.3 Hydro Structures NRHP Eligibility Assessment Study
The specific goal of the Hydro Structures NRHP Eligibility Assessment Study was to conduct an
evaluation of Project structures to determine if the structures are eligible for the NRHP. The
specific objectives included: 1) assessment of Project structures to determine if they are historic
properties; and 2) identification of the features contributing to the NRHP eligibility of Project
structures.
The study report provides a detailed summary of the archival research, descriptions of the Project
structures, a detailed historic context for hydroelectric development at both the national and state
levels, and an NRHP evaluation of the Project facilities.
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Updated Study Report Keowee - Toxaway Hydroelectric Project
FERC No. 2503
The FERC- approved Hydro Structures NRHP Eligibility Assessment Study was completed in
2012 and the final report was filed with the ISR on January 25, 2013.
2.4 Recreation Use and Needs Study
Pursuant to the January 27, 2012 Study Plan Determination Letter, the Recreation Use and Needs
(RUN) Study was approved by the FERC with minor clarifications.
The goal of the RUN Study was to determine the potential need for providing new or enhanced
public recreational facilities to support the current and future needs of the Project, over the life of
the New License. Information collected from this study will be used to develop a new Project
Recreation Management Plan, which will be filed with the Application for New License. The
objectives detailed in the FERC- approved study plan included the following.
• Characterize current public recreation activity and satisfaction levels at the Project
• Estimate future demand for recreational facilities and services at the Project
• Estimate current boating density and carrying capacity at the Project
• Delineate the boundaries of, and estimate current boating density and carrying capacity of
selected boating constriction areas on Lake Keowee
• Identify coincidences of high boating density and high boating conflict areas (as identified by
survey respondents) on Lake Keowee
• Benchmark best practices for enhancing boater safety in constricted areas on Lake Keowee
• Characterize the economic value of recreation generated by the Project
The FERC- approved RUN Study was completed and the final study report was filed with the
April 29, 2013, Study Progress Report.
2.5 Shoreline Erosion Study
Pursuant to the January 27, 2012 Study Plan Determination Letter, the scope of the Shoreline
Erosion Study was expanded by the FERC to include an assessment of the causes of erosion
occurring at the Project and to include Lake Keowee and its islands. Accordingly, Duke Energy
modified the study plan to address the FERC's requirements and filed an addendum to the study
plan with the FERC as part of the Study Progress Report filed on June 15, 2012. The objectives
detailed in the FERC- approved study plan included the following.
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Updated Study Report
Keowee - Toxaway Hydroelectric Project
FERC No. 2503
• Characterize the overall erosion at each lake (including islands)
• Identify Project- induced erosion sites on both reservoirs
• Quantify the level or rate of erosion occurring at those sites
• Collect adequate data on the erosion issue and the Project effect to evaluate the potential
needs or opportunities for erosion - related PM &E and monitoring measures at certain sites
The FERC- approved Shoreline Erosion Study was completed and the final study report was filed
with the ISR on January 25, 2013.
2.6 Shoreline Classification Map Update Study
The goal of the Shoreline Classification Map Update Study was to gather the information
necessary to update the current shoreline classification maps for the Project. The updated maps
depict new shoreline uses since the previous Shoreline Management Plan (SMP) maps were
developed, adjustments to shoreline classifications made by Duke Energy personnel during field
review of permitting activities, correction of previously - identified mapping errors, and other
information (e.g., cultural resource, recreation, etc.) collected as part of the relicensing process to
ensure it is considered during the lake -use permitting process.
As discussed in the ISR filed on January 25, 2013, information was collected in 2012 to support
updates to the shoreline classification maps, and draft shoreline classification maps were
provided to study team members on August 31, 2012. The shoreline classification maps have
been further revised to reflect findings and outcomes resulting from the Avian and Botanical
Studies and Stakeholder Team discussions. The final revised shoreline classification maps will
be filed with the Application for New License as described in the FERC- approved study plan.
2.7 Lake Jocassee Forebay and Tailwater Water Quality Study
The goal of the Lake Jocassee Forebay and Tailwater Water Quality Study was to provide the
information necessary to determine the effects of recent Project modifications (i.e., the
installation of new hydro unit runners) on water quality in the forebay and tailwater of Jocassee
Pumped Storage Station. The objectives detailed in the FERC- approved study plan included the
following.
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Updated Study Report Keowee - Toxaway Hydroelectric Project
FERC No. 2503
• Collect dissolved oxygen (DO) and temperature data from the Jocassee Pumped Storage
Station forebay and tailwater (Lake Keowee)
• Compare data collected to applicable state water quality standards
• Evaluate the need for modifications to Project operations if DO standards are not met
The FERC- approved Lake Jocassee Forebay and Tailwater Water Quality Study was completed
and the final study report was filed with the ISR Meeting Summary on February 22, 2013.
2.8 Keowee Reservoir Water Quality Modeling Study
The goal of the Keowee Reservoir Water Quality Modeling Study was to evaluate the effects of
proposed changes in Project operations on water quality in Keowee Hydro Station flow releases.
The study focused on the development of a calibrated water quality model for Lake Keowee to
be used to evaluate the potential water quality changes with changing water use. Model
simulations of various scenarios were compared to South Carolina water quality standards. The
objectives detailed in the FERC- approved study plan included the following.
• Evaluate the potential impact of Lake Keowee water level fluctuations on both reservoir
water quality and on water quality in subsequent hydro flow releases
• Compare tailrace simulation results to applicable South Carolina water quality standards
• Evaluate the need for modifications to Project operations if applicable South Carolina
water quality criteria for hydro flow releases are not met
The FERC- approved Keowee Reservoir Water Quality Modeling Study was completed and the
final study report was filed with the second season Study Progress Report on April 29, 2013.
Subsequent to filing the final study report, the Operating Scenario Committee (OSC) developed a
proposed Project operation scenario to evaluate Project effects. The Water Quality Resource
Committee (WQRC) subsequently requested this scenario (WQ4) be applied to the calibrated
CE- QUAL -W2 Lake Keowee water quality model (W2 model) to evaluate the influence of
Project operations on the water temperature and DO concentrations in the Keowee Hydro Station
tailrace. The evaluation was intended to quantify comparative differences in water quality
predicted under the WQ4 scenario as compared to modeled output for the Duke Energy Trial
Balloon (WQ3 scenario). As described in the evaluation, modeled water temperatures and DO
concentrations under the WQ4 scenario were comparable to those under the WQ3 scenario.
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Additional information can be found in the Addendum to Keowee Reservoir Water Quality
Modeling Study Report — W2 Model Results Comparing Water Quality Predicted under Duke
Energy Trial Balloon (WQ3) and Revised (WQ4) Operational Conditions, included herein as
Appendix A.
Additionally, after the completion of the Lake Keowee Reservoir Water Quality Modeling Study,
the OSC developed low- and high- impact climate change scenarios to evaluate the effects of
Project operations on reservoir levels, downstream flow releases, and hydropower generation
using Computer Hydro Electric Operations and Planning Software ( CHEOPS), a hydroelectric
operational model. The WQRC subsequently requested similar climate change scenarios be
applied to the calibrated W2 model to evaluate the influence of comparable climate change
assumptions on the temperature and DO levels in the Keowee Hydro Station tailrace. The results
of the application of the W2 model to those CHEOPS - modeled climate change scenarios are
presented in the Addendum to the Keowee Reservoir Water Quality Modeling Study Report —
W2 Model Results from Climate Change Scenarios Using 1998 and 2009 Duke Energy Trial
Balloon (WQ3) Conditions, included herein as Appendix B.
2.9 Reservoir Level and Project Flow Releases Study
The goal of the Reservoir Level and Project Flow Releases Study was to organize historic lake
level data for both Lake Keowee and Lake Jocassee and flow release data for Keowee Hydro
Station into a database format to allow easy electronic access and analysis. The data include all
available reservoir level and flow release data for the entire available record, including both
drought and non - drought times.
The FERC- approved Reservoir Level and Project Flow Releases Study was completed and the
final study report was filed with the ISR on January 25, 2013.
2.10 Operations Model Study
The goal of the Operations Model Study was to simulate various Project operations proposed
during the relicensing process to aid in decision making regarding the effects of various
operating scenarios on water quantity, reservoir levels, hydropower generation, and flow releases
from the Project.
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Water quantity models were developed using proprietary CHEOPSTM and the USACE
Hydrologic Engineering Center's Reservoir System Simulation (HEC ResSim) operations
models. The CHEOPSTM model is capable of detailed modeling of hydro turbine and pumped -
storage operations and can simulate dispatch according to load curve shapes based on economic
energy value information, both of which are important aspects of relicensing and can be custom -
programmed to meet the evolving goals of relicensing stakeholders. Both models have been
validated against historic operations and in respect to each other, and both were used during the
relicensing process as needed. However, CHEOPSTM is the primary modeling tool used to
explore proposed operating scenarios for the relicensing process.
The Operations Model Study has been completed in accordance with the FERC- approved study
plan with minor modifications. Duke Energy submitted the Model Verification Report to the
FERC as part of the June 15, 2012 Study Progress Report. Subsequent to that submittal, the
hydrology dataset for the model was adjusted based on input from the study team and the model
was revised to incorporate the USACE's revised Drought Contingency Plan (DCP) implemented
in July 2012. Accordingly, Duke Energy reissued the model to the study team in October 2012
and submitted the Addendum to the Model Verification Report with the ISR on January 25,
2013.
Subsequent to filing the Addendum to the Model Verification Report, the Operations Model
Scenario Documentation Report was submitted with the second season Study Progress Report on
April 29, 2013. However, additional reservoir operations modeling was performed subsequent to
February 2013 including the scenario included in the Stakeholder Team Relicensing Agreement
and results of selected previously presented scenarios were re -run using a revised - extended
hydrology data set (1939 through 2011). The extended data set (2009 -2011) facilitated review of
the Duke Energy and USACE reservoir system responses to recovery from the 2007 -2008
drought of record based on high inflows experienced in 2009 -2010 over the range of operating
scenarios. The additional reservoir operations modeling performed subsequent to February 2013
is detailed in the Addendum to the Operations Model Scenario Documentation Report, included
herein as Appendix C.
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2.11 Water Supply Study
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The primary goal of the Water Supply Study was to document the current water withdrawals,
water returns, and overall water use within the Keowee - Toxaway Basin, as well as to estimate
future water needs based on reasonable growth projections and assumptions.
The Water Supply Study was conducted in accordance with the FERC- approved study plan with
minor modifications. Development of water use projections for the Water Supply Study
involved compiling a list of water withdrawals and returns greater than or equal to 100,000
gallons per day (GPD) within the Savannah River Basin (Basin). While the study plan calls for
evaluation of water withdrawals and returns within the Basin greater than or equal to 50,000
GPD, only entities with water withdrawals and returns greater than or equal to 100,000 GPD are
presented in the study. This approach was agreed to by the study team during development of
the detailed water use projections for this study. The reasons for increasing the volume of
withdrawals and returns from 50,000 GPD to 100,000 GPD are as follows.
• Water use data for entities with water use equal to or greater than 100,000 gallons per day
are more readily accessible than for those entities with water use less than 100,000
gallons per day. Entities with water use of 100,000 gallons per day or more are required
to report their use to applicable state agencies (specifically, in South Carolina 3,000,000
gallons per month, which equates to 100,000 gallons per day), while those using less than
100,000 gallons per day are not required to report water use.
• Water use for individual entities using less than 100,000 gallons per day is considered
insignificant when compared to the overall water use in the Basin.
The final Water Supply Study Report (dated October 2012) and the Water Supply Study Report
Addendum 1 (dated December 2012) were filed with the ISR on January 25, 2013. The Water
Supply Study Addendum 1 was prepared to address the request of the Water Supply Study Team
to supplement the baseline water yield analysis using the critical intake evaluation constraint
(described in the October 2012 Water Supply Study Report). The analysis discussed within
Addendum 1 focuses on a baseline water yield analysis using a full reservoir usable storage
constraint.
A second addendum to the Water Supply Study Report was prepared in November 2013. The
Water Supply Study Report Addendum 2 includes an analysis that calculates water yields for
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Duke Energy's upstream Bad Creek Project, the Project, and the USACE downstream reservoirs
(Hartwell Lake, R.B. Russell Lake, and J.S. Thurmond Lake) using the proposed operating
scenario included in the Stakeholder Team Relicensing Agreement. Additional information can
be found in the Water Supply Study Report Addendum 2, included herein as Appendix D.
2.12 Wetlands Study
The goal of the Wetlands Study was to identify and characterize the existing wetland habitats
within the FERC Project Boundary. Pursuant to the January 27, 2012 Study Plan Determination
Letter, the FERC required the study to identify hydrologically connected wetlands outside the
FERC Project Boundary affected by current or proposed operations and maintenance, to map
these wetlands, and to assess them to identify Project effects. The objectives detailed in the
FERC- approved study plan included the following.
• Map and classification of existing Project wetlands
• Assess the impact of Project operations, maintenance, and recreation activities on Project
wetlands
• Provide information needed to develop any proposed PM &E measures
The FERC- approved Wetlands Study was completed and the final study report was filed with the
ISR on January 25, 2013.
2.13 Avian Study
The primary goal of the Avian Study was to characterize the avian resources within and
immediately adjacent to the FERC Project Boundary. The objectives detailed in the FERC-
approved study plan included the following.
• Survey and evaluate existing breeding, resident, and migratory avian populations
• Survey and identify the presence of any state or federal rare, threatened or endangered
(RTE) species
• Assess effects of current and proposed Project - related hydropower operations and
maintenance on the breeding and migratory species and communities
• Provide information to assist in developing potential PM &E measures
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The FERC- approved Avian Study was completed and the final study report was filed with the
ISR Meeting Summary on February 22, 2013
2.14 Mammal Study
The goal of the Mammal Study was to characterize the mammalian resources within and adjacent
to the FERC Project Boundary. The objectives detailed in the FERC- approved study plan
included the following.
• Survey and evaluate mammalian populations
• Identify the presence of RTE mammal species
• Assess the effects of current and proposed Project - related hydropower operations and
maintenance on mammalian resources
• Provide information to assist in developing any needed PM &E measures
The FERC- approved Mammal Study was completed and the final study report was filed with the
ISR Meeting Summary on February 22, 2013.
2.15 Botanical Study
The goal of the Botanical Study was to characterize the botanical resources affected by operation
of the Project. The objectives detailed in the FERC- approved study plan included the following.
• Survey and classify the composition of existing vegetation within and adjacent to the
FERC Project Boundary
• Survey and identify the presence of state or federal RTE species
• Assess the potential impacts of Project operations and maintenance on the vegetative
communities
• Provide information to assist in developing appropriate PM &E measures for the botanical
resources at the Project
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The FERC- approved Botanical Study was completed and the final study report was filed with the
ISR Meeting Summary on February 22, 2013. Pursuant to a letter dated March 27, 2013, FERC
issued comments on the Initial Study Report and Initial Study Report Meeting Summary which
included comments on the Botanical Study Report. In response to the FERC's comments, Duke
Energy revised the Botanical Study Report and resubmitted the final Botanical Study Report
with the Study Progress Report submitted on November 6, 2013.

APPENDICES