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Home My WebLink About02_BRBM_HydroLogics_Broad_11oct2011Broad River Basin Hydrologic Model OverviewBroad River Basin Hydrologic Model OverviewCasey Caldwell, E.I.TSteven Nebiker, P.E.Brian McCrodden, P.E.October 11, 2011Casey Caldwell, E.I.TSteven Nebiker, P.E.Brian McCrodden, P.E.October 11, 2011 Meeting Objectives2•Review system-specific operating rules and input data used in basecase model run•Show preliminary results of current and future demand levels Concept of Broad Hydrologic ModelA basinwide model of the Broad River Basin at the finest practical geographic resolution and timestep.Possible Uses:1. Evaluation of the combined effects of municipal water supply plans2. Evaluation of interbasin transfer permit applications3. Development of individual water supply plans –model will be on the DWR server and available to stakeholders and their consultants4. A platform for developing risk-based drought plans.3 Project Timeline•Components–Basin schematic: 1 - 2 months (complete)–Data collection (demands and discharges, including agricultural demands): 4 - 6 months (complete)–Inflow development: 6 – 10 months (complete)–Operating rules: 3 months (complete pending review)–Current and future demand model runs: 2 - 4 months (complete pending review)–Documentation, installation, and training: 1 month–Expected completion date: February 20124 Why Data Collection Matters•Unimpaired flows are important because they allow alternative operating / demand scenarios to be run–Historic impairment data required to unimpair flows•Model should mimic how your system performs–Operating rules–Reservoir operations–Demand and wastewater returns–Drought plans5 Typical Model Output•Flow in the river•Storage and elevation at reservoirs•Derived attributes–Frequency and duration of drought plan activation–Frequency and duration of transfer / sales–Environmental / instream flow statistics6 Overall Schematic7 Broad River Water Authority (BRWA)•Primary source – Broad River•Sells water to Spindale, Rutherfordton–Wastewater treated in these towns•Annual Average Demand = 5.17 MGD–Assume 2.5 is for Polk county in current scenario•Treatment capacity = 8 MGD•Drought Plan–Stage 1 – Flow at Intake < 65 MGD for 7 days• Voluntary – 5% reduction–Stage 2 – Flow at Intake < 20 MGD for 7 days• Mandatory I – Shortage – 10% reduction–Stage 3 – Flow at Intake < 18 MGD for 7 days• Mandatory II – Emergency – 20% reduction–Stage 4 – Flow at Intake < 15 MGD for 7 days• Mandatory III – Crisis – 25% reduction8 BRWA System (from model)9 BRWA System - Simplified10Flow from upstream Broad RiverSpindale sales/wastewater discharge to 2ndBroadRutherfordton sales/wastewater dischargeBRWA total withdrawalBroad River flow Demand Pattern11 0.000.020.040.060.080.100.120.140.160.18Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov DecFraction of Monthly DemandWastewater Pattern - Rutherfordton12** Fraction of total BRWA demand 0.000.050.100.150.200.250.300.35Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov DecFraction of Monthly DemandWastewater Pattern - Spindale13** Fraction of total BRWA demand Polk County•Primary source–Current: BRWA–Future: Lake Adger (expected)•Annual Average Demand = 2.5 MGD•Need drought plan for new reservoir14 Polk County System15Polk Co. DemandLake AdgerFlow from upstreamGreen RiverGreen River flowdownstreamNatural reservoir inflow Stage-Storage Curve – Lake Adger16 Demand Pattern17 Forest City•Primary source – Second Broad River•Annual Average Demand = 1.825 MGD–After sales to Franklin Co.•Treatment capacity = 8 MGD•Drought Plan–Stage 1 – Flow at Intake < 26.8 cfs for 7 days• Voluntary – 5% reduction–Stage 2 – Flow at Intake < 21.4 cfs for 7 days• Mandatory I – 10% reduction–Stage 3 – Flow at Intake < 16.1 cfs for 7 days• Mandatory II – Emergency – 20% reduction–Stage 4 – Flow at Intake < 10.7 cfs for 7 days• Emergency – 25% reduction–Stage 5 – Flow at Intake < 5.4 cfs for 7 days• Rationing (assumed 50% reduction)18 Forest City System19Natural inflow at 2ndBroad IntakeWW DischargeForest City Demand2ndBroad River flow Demand Pattern20 Wastewater Pattern21*0.000.100.200.300.400.500.600.700.800.901.001.10Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov DecFraction of Monthly Demand Cliffside Steam Station•Primary source – Broad River (Cliffside Dam)•Annual Average Demand = 19.4 MGD22 Cliffside Steam Plant System23Cliffside DemandCliffside DamFlow from upstreamBroad River flowdownstreamCooling towerDischargeNatural reservoir inflow Demand Pattern24 Cooling Tower Discharge Pattern25*0.000.100.200.300.400.500.600.700.800.901.001.10Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov DecFraction of Monthly Demand Cleveland County•Primary source – First Broad River•Annual Average Demand = 4.23 MGD•Treatment capacity = 6 MGD•Drought Plan–Stage 1 – Flow at gage (Lawndale) < 25 cfs for 14 days• Voluntary – 5% reduction–Stage 2 – Flow at Gage < 15 cfs for 10 days• Mandatory I – 10% reduction–Stage 3 – Flow at Gage < 10 cfs for 7 days• Mandatory II – Emergency – 20% reduction–Stage 4 – Flow at Gage = 5 cfs for 5 days• Emergency – 25% reduction–Stage 5 – Flow at Gage < 5 cfs• Rationing (assumed 50% reduction)26 Cleveland County System27Flow from upstreamNatural inflow at CCW IntakeCCW DemandFlow towards Shelby1stBroad River Demand Pattern28 Shelby•Primary source – First Broad River–25 cfs minimum downstream flow–Secondary source – Broad River Intake•Annual Average Demand = 3.85 MGD–Sells water to Boiling Springs•Treatment capacity = 12 MGD•Drought Plan (language from plan needs clarification)–Stage 1 – Flow at intake < 30 cfs for 14 days• Voluntary – 5% reduction–Stage 2 – Release 25 cfs for 7 days• Mandatory I – 10% reduction–Stage 3 – Flow at intake < 25 cfs for 7 days• Mandatory II – Emergency – 20% reduction–Stage 4 – Flow at intake < 25 cfs and receiving @ 80% of allocated Broad River intake flow (7.2 MGD)• Emergency – 25% reduction–Stage 5 – Broad River intake >= 9 MGD• Rationing (assumed 50% reduction)29 Shelby System30Natural inflow at IntakeShelby demand nodeWastewater discharge1stBroad River downstream flowUpstream from 1stBroadTotal WDSales to Boiling SpringsWD from Broad River Intake Demand Pattern31 Wastewater Pattern32*0.000.100.200.300.400.500.600.700.800.901.001.10Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov DecFraction of Monthly Demand Kings Mountain•Primary source – Moss Lake (Kings Mt. Reservoir)•Annual Average Demand = 2.43 MGD–Sells water to Grover•Treatment capacity = 8 MGD•Drought Plan–Stage 1 – Storage < 75% • Voluntary - 5% reduction–Stage 2 – Storage < 65%• Mandatory I - 10% reduction–Stage 3 – Storage < 50%• Mandatory II 20% reduction–Stage 4 – Storage < 30%• Emergency 25% demand reduction–Stage 5 – Storage < 10%• Rationing (assumed 50% reduction)33 Kings Mountain System34Moss Lake / Kings Mt ReservoirKings Mtdemand nodeBuffalo CkKM WW DischargeNatural reservoir inflowGrover WW Discharge Stage-Storage Curve – Kings Mtn.35 Demand Pattern36 Wastewater Pattern37*0.000.100.200.300.400.500.600.700.800.901.001.10Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov DecFraction of Monthly Demand Other Reservoirs/Dams – Non Water Supply•Tuxedo Dam (Lake Summit)–Normal pool (upper rule) = 2010.6 ft–Lower rule = 2005.6 ft•Turner Shoals Dam (Lake Adger)–Operated as run-of-river for current scenario–Would be operated with rule curve when used as Polk County supply•Lake Lure–Operated as run-of-river–Minimum Release•Cliffside Dam–Operated as run-of-river•Stice Shoals Dam–Operated as run-of-river38 Gaston Shoals Dam•Normal pool (upper rule)–March = 605.2 ft–Jan-Feb, Apr-Dec = 604.2 ft•Minimum release and bypass flow (see next slide)•Hydropower operating policy and drought protocol are not yet available39 Gaston Shoals – Minimum Release & Bypass Flows40Months Minimum Release (cfs) Bypass Flow (cfsJan – Feb 718 150Mar – Apr518350May301350June501150Jul – Nov438150Dec725150 Other Basin Minimum Releases / Flows41MonthsMinimum Release/Flow (cfs)Lake Lure7Shelby Intake25 Stage-Storage Curve – Lake Summit42 Stage-Storage Curve – Lake Lure43 Stage-Storage Curve – Cliffside44 Stage-Storage Curve – Stice Shoals45 Stage-Storage Curve – Gaston Shoals46 Summary of Major Basin Demands47Utility2010 Average Annual Demand (MGD)BRWA5.7Polk Co.*2.5Forest City1.8Cliffside Steam19.4Cleveland Co.4.2Shelby3.8Kings Mtn.2.4Gaffney (SC)6.1* Included in BRWA for current scenario Additional Basin Wastewater Returns48Utility2010 Average Annual Return (MGD)Lake Lure0.07Rutherfordton0.5Spindale1.2Saluda0.05Columbus0.3Boiling Springs0.3PPG Industries0.7Grover0.05 Monthly Impairments at Boiling Springs (2008)490200400600800100012000510152025303540Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov DecAverage Monthly Gage Flow (cfs)Average Monthly Impairment (cfs)Ag. WDM&I Net WDGage Flow Monthly Impairments at Boiling Springs (2008)50020040060080010001200Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov DecAverage Monthly Impairment (cfs)Ag. WDM&I Net WDGage Flow Future Projections of Major Basin Demands51Utility2010 Average Annual Demand (MGD)2060 Average Annual Demand (MGD)BRWA5.73.9*Polk Co.2.53.5Forest City1.82.6Cliffside Steam (Net WD) 11.420.7Cleveland Co.4.27.9**Shelby3.85.4Kings Mtn.2.42.0Gaffney (SC)8.314.6*2060 BRWA demand is lower because future Polk Co. demand assumed to be met from Lake Adger.** All demands from most recent LWSP on file with DWR, except for CCW 2060 demand, which is from recent planning work. Future Projections of Wastewater Returns52Utility2010 Average Annual Return (MGD)2060 Average Annual Return (MGD)Lake Lure0.070.2Rutherfordton0.50.9Spindale1.21.5Saluda0.050.2Columbus0.30.5Boiling Springs0.30.5PPG Industries0.72.9Grover0.050.2 Sample Output•Unless otherwise noted using current (2010) demand53 Boiling Springs Monthly Gage Flow54 Boiling Springs Monthly Gage Flow55 First Broad Shelby Monthly Flow56 Gaffney Gage Monthly Flow57 Gaston Shoals Monthly Storage58Note: Not modeling any drought protocol for the reservoir Monthly Gaston Shoals Outflow / Blacksburg Gage Flow59 Daily Gaston Shoals Outflow / Blacksburg Gage Flow60 Boiling Springs Monthly Gage Flow – 2010 vs. 2060* Demands61* Only 2060 municipal & industrial demands have been estimated,agricultural demands remain at current levels Forest City Drought Trigger Activations62Note: Frequency/duration of activation does not change with 2060 demand Basin Reservoirs – 2010 Demands63Note: Drawdown only occurs on Gaston Shoals and Moss Lake; other reservoirs are not used for water supply and are generally operated as run-of-river 64 01234567891011121930 1935 1940 1945 1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010Gage Reference NumberTimeline for Gage DataGage TimelineJacobHenryNeboGaffney1stBroad Lawndale1stBroad CasarBoiling Springs2ndBroad Cliffside2ndBroad LoganCove CreekBroad - Chimney65Indian