This email concludes the 2022 Washington Metropolitan Area (WMA) drought exercise. A summary report describing exercise assumptions, activities, and tools will be prepared and published on ICPRB's website (www.potomacriver.org).
Thank you for participating in the exercise and helping to maintain the reliability of the regional water supply system! We extend a special thanks to MWCOG for coordinating the practice Drought Coordination Technical Committee Call Tuesday afternoon. Given the high Potomac River flows during this year's exercises, we did not practice a Little Seneca test release, but we hope to continue this tradition for future events.
All the best,
The ICPRB CO-OP Drought Team
ACTUAL Daily flows:
Little Falls gage flow 2022-11-16: 8855 MGD (13700 cfs)
Little Falls gage flow 2022-11-17: 6980 MGD (est., based on recently available real-time data) (10800 cfs)
Note: Gage flow at Little Falls is measured after water supply withdrawals.
Point of Rocks flow 2022-11-16: 6366 MGD (9850 cfs)
Point of Rocks flow 2022-11-17: 6463 MGD (est., based on recently available real-time data) (10000 cfs)
ACTUAL Yesterday's Washington metropolitan area Potomac River withdrawals and discharges (2022-11-16):
Fairfax Water Corbalis withdrawal (Potomac): 84 MGD
WSSC Water Potomac withdrawal: 120 MGD*
Washington Aqueduct withdrawal: 118 MGD
Loudoun Water withdrawal: 8 MGD
Loudoun Water Broad Run discharge: 7 MGD
Total Potomac withdrawal: 330 MGD
Total net Potomac withdrawal: 323 MGD
*REVISED from Day 3, A.M. WSSC Water withdrawal report
ACTUAL Yesterday's Patuxent, Occoquan, and Net Total System Withdrawal (2022-11-16):
FW Occoquan withdrawal:60 MGD
WSSC Patuxent withdrawal:40 MGD
ACTUAL Yesterday's total system withdrawal (2022-11-16): 422 MGD*
*REVISED from Day 3, A.M. WSSC Water withdrawal report
ACTUAL Today's estimated production* (2022-11-17):
FW estimated production:122 MGD
WSSC estimated production:147 MGD
Washington Aqueduct estimated production:121 MGD
Total estimated production:390 MGD
LW total estimated consumption:21 MGD**
*Based on CO-OP daily demand forecasting models. FW includes the LW purchase and excludes Falls Church. Washington Aqueduct includes Falls Church
**LW total estimated consumption includes purchase and production water and is not included in the total production estimate
ACTUAL Tomorrow's estimated production* (2022-11-18):
FW estimated production:125 MGD
WSSC estimated production:148 MGD
Washington Aqueduct estimated production:120 MGD
Total estimated production:394 MGD
LW Total estimated consumption:21 MGD**
*Based on CO-OP daily demand forecasting models. FW includes the LW purchase and excludes Falls Church. Washington Aqueduct includes Falls Church
**LW total estimated consumption includes purchase and production water and is not included in the total production estimate
SIMULATED Recommended operations for today (DREX Day 3, P.M.):
SIMULATED Fairfax Water: Per operational preference, keep Potomac withdrawals steady. Maintain Griffith WTP at maximum production of 70 MGD.
SIMULATED WSSC Water: Maintain Patuxent at maximum production of 60 MGD. Potomac withdrawals per operational preference, keeping as steady as possible.
SIMULATED Little Seneca Reservoir (release date, time, amount in MGD): Maintain Little Seneca release at 118 MGD.
SIMULATED Washington Aqueduct: Meet all demands from Little Falls in order to maintain the Great Falls flow-by.
SIMULATED North Branch Reservoirs A.M. Summary: Maintain a minimum Luke target = 297 cfs (192 MGD). The assumed Luke flow without water supply releases is 251 cfs (162 MGD) (simulated).
SIMULATED Loudoun Water Potomac River (PR) flow values for drought operations protocol (based on yesterday's flows):
QPR: 723 cfs
QPR, obs: 748 cfs
QPR, WS: 25 cfs
Note: Flow levels have dropped to a level that has triggered enhanced monitoring, per the drought operations manual of the Water Supply Coordination Agreement. When adjusted flow at Little Falls (adjusted flow is gage flow plus upstream withdrawals) less the environmental flow is less than twice the Washington metropolitan area withdrawals, the water suppliers will begin reporting yesterday's and today's withdrawals and this morning's reservoir storage volumes. ICPRB asks that communications be sent by 7:30 am and updates sent by 1:00 pm. Reporting can be submitted through www.icprbcoop.org, by email to coop@icprb.org, or by telephone by leaving a message with the CO-OP operations number at 301-274-8132. Monitoring emails can be viewed at http://icprbcoop.org/products/monitoring-reports. Thank you for your contribution to the monitoring efforts.