Hydrologic Modeling Workshop. HEC-5 Modeling of ACF Interim Operation by Mobile District

Transcription

1 Hydrologic Modeling Workshop HEC-5 Modeling of ACF Interim Operation by Mobile District May 24, 2006

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3 Model Settings Demands Hydropower Water Supply 2001 actual Required Flow Atlanta Columbus Jim Woodruff Outflow Operation Balanced 4 federal reservoirs Based on Comp Study Black & White

4 Model Settings C LANIER: OPERATES FOR ATLANTA AND WEST POINT DAM C TOP ZONE ELEVATIONS: /1: /2: /3: /4: / C POWER (WEEKDAYS): /1: 3 HRS /2: 2 HRS /3: 2 HRS /4: 0 HRS/ C 450 CFS CONTINUOUS RELEASE (LEAKAGE) C ATLANTA MIF = 750 CFS C C WEST POINT: OPERATES FOR COLUMBUS, W.F. GEORGE C TOP ZONE ELEVATIONS: /1: /2: /3: /4: / C POWER (WEEKDAYS): /1: 4 HRS /2: 2 HRS /3: 2 HRS /4: 0 HRS / C 675 CFS CONTINUOUS RELEASE (LEAKAGE) C COLUMBUS MIF = 1,850 CFS (WP > 621.6), 1,200 CFS (WP < 621.6) C C W.F. GEORGE: OPERATES FOR WOODRUFF C TOP ZONE ELEVATIONS: /1: /2: /3: /4: / C POWER (WEEKDAYS): /1: 4 HRS /2: 2 HRS /3: 2 HRS /4: 0 HRS / C POWER (WEEKEND): /1: 2 HRS /2: 1 HRS /3: 1 HRS /4: 0 HRS / C 0 CFS AVERAGE DAILY MINIMUM RELEASE (CP) C C JIM WOODRUFF: OPERATES FOR CHATTAHOOCHEE C TOP ZONE ELEVATIONS: /1: 77.8/2: 77.1/3: 76.8/4: 76.74/ C POWER: 7200 MWH/MONTH (WCP) C 100 CFS CONTINUOUS RELEASE (LEAKAGE) C C DEMANDS YEAR 2000 ACTUAL. C NAVIGATION - NO DEMAND

5 Woodruff Required Outflow Preprocess Spreadsheet (JWoutflows.xls) Based on Basin Inflows (BI) 7 day moving average 2 Seasons March May (spawning) June February Storage Ratio 70% 90%

6 Woodruff Required Outflow Values imported to DSS HEC-5 Chattahoochee Minimum Flow Flow (cfs) Jan Jul Jan Jul Jan Jul Jan Jul BASIN_INFL INITIAL FLOW-RES IN Basin Inflow CHATTAHOOCHEE INITIAL FLOW-DESIRED Woodruff Required Outflow

7 Interim Plan Ramping Rates Exceed Powerhouse Capacity (18,000 cfs) 0.5 to 1.0 ft/day* Within Powerhouse Capacity and > 8,000 cfs 0.25 to 0.5 ft/day* Within Powerhouse Capacity and < 8,000 cfs 0.25 ft/day or less* * Consistent with safety requirements, flood control operations, and equipment constraints

8 Ramping Rate Development Chattahoochee Rating foot change at Chattahoochee in cfs 1 ft change/ cfs Flow 1ft change/cfs Flow, cfs x 0.25 ft = 365 cfs

9 Maximum Fall Rate in Model Ramping Rate Elevation Maximum Fall Rate, cfs Flow Basin Inflow, cfs n Maximum Fall Rate, feet Flow Elevation

10 Model Runs Model Demands Storage Ratio Ramping INTERIM_YR 2K % Yes INTERIM_YR 2K_NR % No INTERIM_90_ YR2K % Yes INTERIM_90_ YR2K_NR % No

11 Buford - Ramping Impact Elev (ft) Historic Ramping No-Ramping 1035 Jan Jul Jan Jul Jan Jul Jan Jul BUFORD DAM YR2000 ELEV BUFORD DAM YR2000NR ELEV BUFORD DAM OBS_ADJ ELEV

12 Buford - Ramping Impact Ramping No-Ramping 1065 Elev (ft) BUFORD DAM YR2000 ELEV Jul Jan Jul Jan Jul Jan Jul BUFORD DAM YR2000NR ELEV

13 Buford - Ramping Impact Ramping No-Ramping Elev (ft) BUFORD DAM YR2000 ELEV Jul Jan Jul Jan Jul Jan Jul BUFORD DAM YR2000NR ELEV

14 Buford - Storage Ratio Impact % Basin Inflow 90% Basin Inflow Elev (ft) BUFORD DAM YR2000 ELEV Jul Jan Jul Jan Jul Jan Jul BUFORD DAM YR2000_90 ELEV

15 Buford - Storage Ratio Impact % Basin Inflow 90% Basin Inflow 1068 Elev (ft) BUFORD DAM YR2000 ELEV Jul Jan Jul Jan Jul Jan Jul BUFORD DAM YR2000_90 ELEV

16 West Point - Storage Ratio Impact % Basin Inflow 90% Basin Inflow 635 Elev (ft) WEST POINT YR2000 ELEV Jul Jan Jul Jan Jul Jan Jul WEST POINT YR2000_90 ELEV

17 West Point - Ramping Impact Ramping No-Ramping 635 Elev (ft) WEST POINT YR2000 ELEV Jul Jan Jul Jan Jul Jan Jul WEST POINT YR2000NR ELEV

18 WF George - Ramping Impact Ramping No-Ramping Elev (ft) W.F. GEORGE YR2000 ELEV Jul Jan Jul Jan Jul Jan Jul W.F. GEORGE YR2000NR ELEV

19 WF George - Storage Impact % Basin Inflow 90% Basin Inflow Elev (ft) W.F. GEORGE YR2000 ELEV Jul Jan Jul Jan Jul Jan Jul W.F. GEORGE YR2000_90 ELEV

20 Chattahoochee - Ramping Impact Average daily difference of 9 cfs Additional water required for ramping Flow (cfs) Ramping No-Ramping Jan Jul Jan Jul Jan Jul Jan Jul CHATTAHOOCHEE YR2000 FLOW-REG CHATTAHOOCHEE YR2000NR FLOW-REG

21 Chattahoochee - Ramping Impact Ramping No-Ramping Flow (cfs) Jul Aug Sep Oct Nov Dec Jan 1999 CHATTAHOOCHEE YR2000 FLOW-REG CHATTAHOOCHEE YR2000NR FLOW-REG

22 Chattahoochee - Storage Ratio Impact Average diff 2.4 cfs Flow (cfs) % Basin Inflow 90% Basin Inflow Jan Jul Jan Jul Jan Jul Jan Jul CHATTAHOOCHEE YR2000 FLOW-REG CHATTAHOOCHEE YR2000_90 FLOW-REG

23 Chattahoochee - Storage Ratio Impact ,907,326 additional DSF 4,476,832 additional DSF/yr Additional 1,035 cfs/day required Flow (cfs) Jan Jul Jan Jul Jan Jul Jan Jul CHATTAHOOCHEE YR2000 FLOW-REQUIRED 70% Basin Inflow 90% Basin Inflow CHATTAHOOCHEE YR2000_90 FLOW-REQUIRED

24 Jim Woodruff Release Decision CASE-RES Release Summay % of Time Case Description 40% 0.00 Required Release 32% 0.02 Max Rate of Change 27% 0.03 Reach Top of Conservation 1% 0.06 Max Release due to Outlet Capacit Jan Jul Jan Jul Jan Jul Jan Jul JIM WOODRUFF YR2000 CASE-RES

25 Net 2000 Demands above Whitesburg Flow, cfs Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec COE Values GA Values COE Values GA Values

26 Net 2000 Demands Jim Woodruff - Flint River Flow, cfs Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec COE Values GA Values COE Values GA Values

27 Summary Model captures Basin Inflow Woodruff discharge relationship Fall ramping rate Balance operation, greatest demand on downstream reservoirs

28 Next Step Incorporate improvements from modeling meeting Fine tune fall rate for flows > 20,400 Period of record simulation Measure impacts during critical period Reality check - water management team review modeling results to measure real life applicability