CONCLUSION OF THE DROUGHT EXERCISE - Afternoon simulated Potomac flow and demand update (Tuesday 10/11/2020) - DROUGHT EXERCISE
This afternoon email report concludes CO-OP's 2016 Washington Metropolitan Area Drought Exercise. We conduct these exercises every year to practice communications and operational procedures that would be used in case of actual low flow conditions in the Potomac River. Thank you all for helping us stay well prepared for drought!
ACTUAL - Basin and system conditions:
Yesterday's basin-wide average precipitation (above Little Falls):
0 inches
(based on CO-OP's Low Flow Forecast System analysis of MARFC gridded multisensor precipitation estimates)
Daily Flows:
Little Falls gage flow 10/10: 1810 MGD (2800 cfs)
Point of Rocks gage flow 10/10: 1980 MGD (3070 cfs)
Note: Gage flow at Little Falls is measured after water supply withdrawals.
Little Falls gage flow 10/11: 1840 MGD (2850 cfs)
Point of Rocks gage flow 10/11: 2290 MGD (3540 cfs)
Net Potomac Production (10/10/20):
FW Corbalis raw water withdrawal (Potomac): 96 MGD
WSSC Potomac Production: 110 MGD
Aqueduct withdrawal: 129 MGD
Total Potomac demand: 336 MGD
Patuxent, Occoquan, and Net Total System Production (10/10/20):
WSSC Patuxent withdrawal: 52 MGD
FW Occoquan raw water withdrawal: 71 MGD
Total System demand: 458 MGD
Today's estimated demand (10/11/20) P.M.:
WSSC P.M. estimated demand: 162 MGD
FW P.M. estimated demand: 160 MGD
Aqueduct P.M. estimated demand: 135 MGD
Total P.M. estimated demand: 457 MGD
Tomorrow's estimated demand (10/12/20):
WSSC estimated demand: 160 MGD
FW estimated demand: 160 MGD
Aqueduct estimated demand: 140 MGD
Total estimated demand: 460 MGD
Loudoun Water Broad Run Discharge:
Yesterday's (10/10/20): 9 MGD
Today's (10/11/20): 9 MGD
Tomorrow's (10/12/20) : 9 MGD
Loudoun Water demand:
Yesterday's (10/10/20): 9 MGD
Today's (10/11/20): 9 MGD
Tomorrow's (10/12/20) : 9 MGD
SIMULATED - Recommended operations for today (10/11/20):
Fairfax Water:
Continue withdrawing minimum from Potomac.River
Occoquan withdrawal: 100 MGD (flexible)
Potomac withdrawal: 60 MGD (firm)"
WSSC:
Starting as soon as possible, implement a Potomac to Patuxent load shift by reducing Potomac withdrawals by 30 MGD. Patuxent production per operational preference.
Seneca (release date, time, amount in MGD):
Initiate a water supply release of 140 MGD starting as soon as possible.
Aqueduct:
Meet all demands from Little Falls.
North Branch Reservoirs:
Initiate a water supply release with a Luke target of 173 cfs. The assumed Luke flow without water supply releases is 120 cfs (simulated).