Afternoon Potomac flow and demand update (Wednesday, 2023-09-06)
River flows at Little Falls continue to decline. The proactive voluntary load shift from Great Falls to Little Falls by Washington Aqueduct is still ongoing.
Monitoring Reports
During periods of drought, the Cooperative Water Supply Operations on the Potomac (CO-OP) helps manage the Washington metropolitan area water supply system by coordinating withdrawals from the Potomac River and off-river reservoirs and recommending releases from upstream reservoirs when forecasted flow in the river is not sufficient to meet expected needs. These needs include water demands and an environmental flow-by of 100 million gallons per day (MGD) on the Potomac River at Little Falls dam near Washington, D.C.
Morning Potomac flow and demand update (Wednesday, 2023-09-06)
According to Middle Atlantic River Forecast Center forecasts, small amounts of rain are expected in the basin tomorrow, and accumulations of approximately ½ inch are expected over the next three days. The longer-term forecasts are currently very promising, with accumulations of 1 to 2 inches expected. Tropical Storm Lee is expected to become a major hurricane, with potential impacts on the eastern US.
Afternoon Potomac flow and demand update (Tuesday, 2023-09-05)
According to the real-time USGS gage flow at Little Falls, flows have fallen from 409 MGD (633 cfs) to 365 MGD (565 cfs) since this morning.
Based on yesterday's daily flow and withdrawals, flows fell below the numerical threshold for the Alert Stage of the Low Flow Allocation Agreement (LFAA).
Morning Potomac flow and demand update (Tuesday, 2023-09-05)
According to Middle Atlantic River Forecast Center predictions, no rain is expected for the next 24 hours. Forecasts suggest an average basin rainfall of around 0.15 inches over the next three days and 0.83 inches over the next week.
The proactive voluntary load shift from Great Falls to Little Falls by Washington Aqueduct is still ongoing.
Afternoon Potomac flow and demand update (Monday, 2023-09-04)
Little precipitation is expected in the Potomac basin over the next several days according to National Weather Service forecasts.
Morning Potomac flow and demand update (Monday, 2023-09-04)
According to Middle Atlantic River Forecast Center predictions, a trace of rainfall is expected in the basin over the next 3 days. The week-long outlook points to an approximate total of 0.02 inches across the basin.
Afternoon Potomac flow and demand update (Sunday, 2023-09-03)
River flows at Little Falls have been relatively steady over the past day.
The proactive voluntary load shift from Great Falls to Little Falls by Washington Aqueduct is still ongoing.
Morning Potomac flow and demand update (Sunday, 2023-09-03)
No rain fell in the basin in the past 24 hours. According to Middle Atlantic River Forecast Center predictions, no rain is expected in the next 72 hours. The week-long outlook points to an approximate total of 0.1 inches across the basin.
The proactive voluntary load shift from Great Falls to Little Falls by Washington Aqueduct is still ongoing.
Recent basin-wide average precipitation (above Little Falls):
Afternoon Potomac flow and demand update (Friday, 2023-09-01)
ICPRB CO-OP enhanced drought monitoring will continue throughout the holiday weekend. Please continue to review the accuracy of the data in your automated emails, verify that the file includes all requested data, and email any additional data to coop@icprb.org. Thank you for your continued cooperation through the holiday weekend.
Best,
ICPRB CO-OP Drought Team
Afternoon Potomac flow and demand update (Thursday, 2023-08-31)
River Flows at Little Falls continue to decline and are currently at 587 cfs.
Washington Aqueduct’s voluntary load shift from Great Falls to Little Falls is still ongoing.