Situational Awareness (Thursday, 2025-09-25)
Potomac River flows are expected to rise slightly over the next several days according to Middle Atlantic River Forecast Center (MARFC) predictions. MARFC estimates that total rainfall over the past three days has ranged from 0.25 to 1 inches in most portions of the Potomac watershed above Little Falls. Cumulative precipitation forecasts call for 0.50 to 0.75 inches of rain over the next three days.
Special Conditions
None
Daily flows:
Little Falls gage flow 2025-09-24: 1008 MGD (1560 cfs)
Little Falls gage flow 2025-09-25: 1060 MGD (est., based on recently available real-time data) (1640 cfs)
Note: Gage flow at Little Falls is measured after water supply withdrawals.
Point of Rocks flow 2025-09-24: 1138 MGD (1760 cfs)
Point of Rocks flow 2025-09-25: 1047 MGD (est., based on recently available real-time data) (1620 cfs)
Yesterday's estimated daily flows:
Great Falls estimated flow 2025-09-24: 1008 MGD (1560 cfs)
Note: Estimated flow below Great Falls intake is flow at Little Falls plus Little Falls water supply withdrawal.
Yesterday's Washington metropolitan area Potomac River withdrawals and discharges (2025-09-24):
Fairfax Water Corbalis withdrawal - Potomac: 100 MGD
WSSC Water Potomac withdrawal: 148 MGD
Washington Aqueduct withdrawal - Great Falls: 144 MGD
Washington Aqueduct withdrawal - Little Falls: 0 MGD
Loudoun Water withdrawal: 12 MGD
Loudoun Water Broad Run discharge: 7 MGD
Total Potomac withdrawal: 404 MGD
Total net Potomac withdrawal: 397 MGD
Loudoun Water Potomac River (PR) flow values for drought operations protocol (based on yesterday's flows):
QPR: 1760 cfs
QPR, obs: 1760 cfs
QPR, WS: 0 cfs