DUKE ACCEPTED 8 ENERGY.
BUILDING A SMARTER ENERGY FUTURE FOR
Public Service Commission of South Carolina Allowable Ex Parte PROCESSING Managing Duke Energy - Hydroelectric Projects 2018 July 27 11:17 AM - SCPSC - ND-2018-19-E
July 23, 2018 - Page PRESENTED BY:
Duke Energy Carolinas (DEC) and Duke Energy Progress (DEP) 1 of 21 ACCEPTED 1%0 DUKE 8 ENERGY. FOR PROCESSING - 2018
Introduction July 27 Kodwo Ghartey-Tagoe 11:17
Duke Energy AM President, South Carolina - SCPSC - ND-2018-19-E - Page 2 of
2 21 ACCEPTED 1%0 DUKE Hydroelectric reservoirs support regional needs 8 ENERGY.
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'a Charlotte - 0 2018 v Matthews Southern tn
'Q July
ock Hill, k 53 QM R kinphem 0 I I 27 Lsunnburp
0 11:17 Keowee-Toxaway Catawba-Wateree I AM and Bad Creek t Dillon Nsrtsvrlle 0 -
0 SCPSC Wsrnesvilte Ds Ilrrlpton 0 Newberry Camden ~a~ Dreenwoodnt. Florence - ND-2018-19-E 32 hydro reservoirs enable: . Recreation . Hydropower . Shoreline development . Thermoelectric power . Flood and drought management - . Drinking water . Economic growth Page 3 of
3 21 ACCEPTED 1%0 DUKE 8 ENERGY. FOR PROCESSING - 2018
Presenter July 27 Jeff Lineberger 11:17
Duke Energy AM Director, Water Strategy and Hydro Licensing - SCPSC - ND-2018-19-E - Page 4 of
4 21 ACCEPTED Hydro operations are highly regulated FOR Technical studies Water quality certifications (N.C. and S.C.) PROCESSING Stakeholder agreements Endangered species conditions Legal settlement agreements Fish passage prescriptions License
“Ingredients” - 2018
FERC licenses (30-50 years) regulate hydro operations and shape the rivers’ uses July
including: 27 11:17 Normal Conditions Drought Conditions Emergency Conditions AM - . Lake levels . Drought protocols . Emergency River Access SCPSC License . Aquatic flows . High Water Events -
Requirements . Recreation flows . Grid Emergencies ND-2018-19-E . Recreation facilities . Unexpected Outages . Planned Outages - Page 5 of
5 21 ACCEPTED 1%0 DUKE Regional importance = stakeholder collaboration opportunities 8 ENERGY. FOR PROCESSING - 2018
. Hydro relicensing processes embraced stakeholder collaboration July
o 250+ stakeholder representatives 27 11:17 o Hundreds of public workshops AM Independently facilitated teams
o - SCPSC o Informed by sound science and engineering
. Emphasis on making the rivers better for all interests for next FERC license term - ND-2018-19-E . All stakeholders negotiated relicensing agreements (most signed binding agreements) . End product: Stakeholder-supported “new vision” tailored to meet regional needs - Page “Alone we can do so little; together we can do so much.” 6
– Helen Keller of
6 21 ACCEPTED 1%0 DUKE Managing the extremes 8 ENERGY. FOR Droughts PROCESSING
. Drought management advisory groups
. Public water utilities, industries, resource - agencies, DEC/DEP 2018
. Shared resource = shared responsibility July . 27
Drives Low Inflow Protocol (LIP) implementation 11:17 and communications . https://www.duke-energy.com/community/lakes AM - . SCPSC LIP is single most important drought management Lake Jocassee at 26.3 feet below full pond on Oct. 6, 2008 tool in the applicable river basins - . “Safety net” for public drinking water, industrial ND-2018-19-E water users, aquatic communities and power generation that never existed before - Page 7 of
7 21 ACCEPTED 1%0 DUKE 8 ENERGY. FOR PROCESSING - 2018
Presenter July 27 Randy Herrin 11:17
Duke Energy AM Vice President, Carolinas Regulated Renewables - SCPSC - ND-2018-19-E - Page 8 of
8 21 ACCEPTED 1%0 DUKE Hydropower is the original renewable energy source ENERGY
. 100+ years of clean, renewable hydropower FOR
. 5.2 million MWh of electricity produced in 2017 by PROCESSING DEC and DEP hydros combined . Provides flexible and dispatch-capable energy to customers - 2018 July
Catawba hydro, circa 1904 (replaced by Wylie hydro in 1925) 27 11:17 AM - SCPSC - ND-2018-19-E - Page
Great Falls hydro Cowans Ford hydro 9 of
9 21 ACCEPTED 1%0 DUKE Storing energy and integrating renewables ENERGY FOR . Bad Creek and Jocassee pumped storage PROCESSING hydros have reversible generating units
o Generate to meet electric demand o Pump water back uphill to store energy - 2018 o Tremendous grid support . Pumped storage hydro helps add other July
renewables, like solar, to the grid 27 11:17 . DEC is adding approximately 335 megawatts to Bad Creek Pumped Storage Station
Bad Creek over the next five years AM - SCPSC - ND-2018-19-E - Page Jocassee Pumped Storage Station 10 of
10 21 ACCEPTED 1%0 DUKE Managing the extremes 8 ENERGY. FOR Floods PROCESSING . Every storm is unique . Fundamentals:
Prepare -
o 2018 o Predict and store runoff July Systematically release water o 27 11:17 o Minimize safety/property risks
o Communicate AM - SCPSC - ND-2018-19-E - Page Lake with gated spillway: Lake with ungated (overflow) spillway:
Full pond (100 feet) = top of spillway gates Full pond (100 feet) = crest of spillway 11 of
11 21 ACCEPTED 1%0 DUKE High river flows 8 ENERGY FOR Lakes with ungated (overflow) spillways PROCESSING . When there is more river flow coming into the lake than can be passed through the powerhouse, the lake level rises above the crest of the spillway and flows over the
top. - 2018 . The lake level will be higher than full pond for the remainder of the storm event. July 27 . The simple, effective design of an open spillway allows 11:17 large volumes of excess water to move downstream. AM - SCPSC - ND-2018-19-E - Page Wateree Hydro Station and dam 12 of
12 21 ACCEPTED 1%0 DUKE High river flows 8 ENERGY FOR Lakes with gated spillways PROCESSING . DEC and DEP will not allow water to spill over these gates since trash or floating debris could impact gate operability. -
. When there is more river flow coming into the lake than 2018 can be passed through the powerhouse, spillway gates are opened to pass the extra flow. July 27 . A gated spillway consists of manually and automatic 11:17 operated floodgates that are tested on a routine basis. AM - SCPSC - ND-2018-19-E - Page Tillery flood gates 13 of
13 21 ACCEPTED 1%0 DUKE Subtropical Storm Alberto 8 ENERGY. FOR Catawba-Wateree focus PROCESSING . Region received significant amounts of rain, including in the Upper Catawba River Basin . This storm followed a wet April and May – soils -
were already saturated and lakes were above 2018 normal seasonal targets July . Prior to Alberto, DEC was lowering lake levels to 27 their normal seasonal targets 11:17 . Throughout the storm and the related high inflow event, DEC coordinated closely with local AM -
emergency response officials SCPSC USGS: United States Geological Survey . Updated lake information was posted on the -
DEC toll-free phone system (800.829.5253) and ND-2018-19-E website: www.duke-energy.com/community/lakes - Page 14 of
14 21 ACCEPTED Subtropical Storm Alberto
Catawba-Wateree focus FOR • Reservoir storage in NC (e.g., Lakes James and Norman) mitigated impacts to SC reservoirs • Lake James rose to about 3.5 ft. over full pond and Lake Norman was at 100 ft. and rising (very rare) PROCESSING • Lake Wateree did not begin to rise and spill until after Lakes James and Norman storage was filled
Catawba-Wateree Reservoir Levels -
106.0 2018 Alberto
104.0 July
102.0 27 11:17 100.0 AM 98.0 - SCPSC 96.0
94.0 - ND-2018-19-E 92.0
Lake James Lake Norman Lake Wateree Full Pond Elevation - Page 15 of
15 21 ACCEPTED After a high-water event FOR Catawba-Wateree focus PROCESSING . DEC is required by our FERC license1 and Comprehensive Relicensing Agreement2 to lower reservoirs back to their seasonal target levels. This means moving water downstream through the 11-reservoir system for days. -
. Spilling at reservoirs with no flood gates (about one foot over full pond) expedites returning lake levels to 2018 normal and prepares for future rain events. July . Lake Wateree, the most downstream reservoir, has to pass all the high water from all 10 upstream 27 reservoirs, which takes days. 11:17 AM - SCPSC - ND-2018-19-E
1FERC License: https://www.duke-energy.com/_/media/pdfs/community/lakes-and-rec/ferc-order-new-cw-license-11-25-2015.pdf - 2Comprehensive Relicensing Agreement: https://www.duke-energy.com//_/media/pdfs/community/comp-relicensing-agreement.pdf Page 16 of
16 21 ACCEPTED Lake Wateree FOR Past and future PROCESSING . Over the past 15 months, Lake Wateree has spilled two other times with both of those times being less than one foot over full pond. . Modifications to the Wateree spillway are scheduled for completion by March 2026 to increase flow release -
capacity by 10,000 cfs (nearly 75,000 gallons per second = over 400 Olympic-sized swimming pools per hour). 2018 July
Lake Wateree Lake Level 27
102.00 11:17 101.00
100.00 AM
99.00 - SCPSC 98.00 97.00 96.00 - 95.00 ND-2018-19-E 94.00 93.00 92.00 - Lake Level ft. (local datum, 100 ft. = Full Pond) = Full 100 ft. datum, (local ft. Level Lake Page
Actual Lake Level Full Pond Elevation 17 of
17 21 ACCEPTED Myth versus truth in managing Catawba-Wateree floods FOR
Myth: DEC manages flooding events differently on the North Carolina lakes (e.g., Norman) than the South PROCESSING Carolina lakes. Truth: Management fundamentals are exactly the same. Differences from lake-to-lake arise from lake-specific factors (e.g., gated v. ungated spillways, location/amount of the rainfall, shoreline topography, etc.). - 2018 July
Myth: These lakes were designed for flood control, but DEC doesn’t operate them that way. 27 11:17 Truth: Flood control reservoirs (e.g., Lake Hartwell) have normal target levels that are lower and provide much greater unused water storage capacity. Catawba-Wateree lakes’ target storage is closer to the full pond storage, AM providing some ability to help manage modest flooding events. - SCPSC - ND-2018-19-E
Myth: DEC waits too long to begin drawing down reservoirs when a storm is approaching. Truth: Forecasting actual inflow from an approaching storm is complex and not an exact science. DEC
balances preparatory drawdowns with the possibility the storm will miss the river basin to avoid an unintentional - water shortage. Page 18 of
18 21 ACCEPTED 1%0 DUKE 8 ENERGY. FOR PROCESSING - 2018
Presenter July 27 Jeff Lineberger 11:17
Duke Energy AM Director, Water Strategy and Hydro Licensing - SCPSC - ND-2018-19-E - Page 19 of
19 21 ACCEPTED 1%0 DUKE Getting to the next century 8 ENERGY.
Catawba-Wateree Water Management Group FOR . Organization and Purpose PROCESSING
o 501c(3) nonprofit corporation formed in 2007 o 18 public water utilities and DEC o $550,000 total annual member dues
Purpose is to enhance river’s ability to support human needs while -
o 2018 protecting the environment July
. Together we can do so much – Over $5 Million invested so far in technical 27
projects such as: 11:17 Irrigation efficiency improvements o AM Water conservation tool kit o - SCPSC o Water intake contingency plans o Reducing water loss -
o Sedimentation and groundwater monitoring ND-2018-19-E o Better water demand forecasting and modeling Rock Hill water intake on Lake Wylie . Water Supply Master Plan (www.catawbawatereewmg.org) - Page o Integrated resource planning in one river basin for water utilities and DEC Includes actions to extend shared water supply at least to 2100 o 20 of
20 21 ACCEPTED 1%0 DUKE 8 ENERGY. FOR PROCESSING QUESTIONS? - 2018 July 27 11:17 AM - SCPSC - ND-2018-19-E - Page 21 of
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