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.

Daily Potomac flow and demand update (Saturday 07/10/2010)

Submitted by admin1 on Sat, 07/10/2010 - 09:00

Flow at Little Falls is currently 1520 cfs (980 MGD). The MARFC observed precipitation map shows that much of the western part of the basin received 0.05 to 1 inch of rain in the past 24 hrs. The National Weather Service (NWS) quantitative precipitation forecasts (qpf) indicate a chance of 0.75 to 3.2 inches of accumulated rain across the basin over the next 5 days. Today 0.25 to 0.5 inches of rain is expected for the Washington, D.C. area.

Daily Potomac flow and demand update (Friday 07/09/2010)

Submitted by admin1 on Fri, 07/09/2010 - 09:00

Stream flows continue to fall throughout the basin. Yesterday's daily mean flow at Little Falls was 890 MGD (1370 cfs). The July 4th whitewater release is almost past Point of Rocks, and should be arriving at Little Falls today - producing a short-term uptick in flow.

MARFC's observed precipitation maps indicate that there were scattered thunderstorms in the basin over the past 24 hours, with accumulations
of 1/2 to 1.5 inches in a few localized areas. MARFC predicts accumulations of over an inch throughout much of the basin in the next 48 hours.

Daily Potomac flow and demand update (Thursday 07/08/2010)

Submitted by admin1 on Thu, 07/08/2010 - 09:00

Flow at Point of Rocks is currently 2,070 cfs (1,340 MGD). The increase in Point of Rocks flow is likely due to the 6 hour whitewater release from Savage of 1,000 cfs, which should be recorded sometime today. The basin has received no rain for the month of July, which is 0.7 inches below normal. The National Weather Service (NWS) quantitative precipitation forecasts (qpf) indicate a chance of 0.75 to 1.9 inches of accumulated rain across the basin over the next 5 days.

Daily Potomac flow and demand update (Wednesday 07/07/2010)

Submitted by admin1 on Wed, 07/07/2010 - 09:00

Flow at Point of Rocks is currently 1,910 cfs (1,234 MGD). The basin received no rain yesterday. The National Weather Service (NWS) quantitative precipitation forecasts (qpf) indicate a chance of 0.75 to 1.5 inches of accumulated rain across the basin over the next 5 days. On July 4, there was a 6 hour whitewater release from Savage of 1,000 cfs. The release passed the Hancock gage yesterday.

Discontinuing Daily Monitoring - Potomac flow and demand update, (Wednesday 10/21/09)

Submitted by admin1 on Wed, 10/21/2009 - 09:00

Flow at Point of Rocks is currently 2,710 cfs. The Potomac basin is forecasted to receive 0.75 to 1.00 inch of rain over the next five days. The Corps continues its release from Savage Reservoir of approximately 100 cfs.

Flow at Point of Rocks has remained above the low flow monitoring threshold for several days running. Therefore, daily monitoring will be discontinued until further notice. Thank you to all for your contribution to the monitoring efforts. If flow at Point of Rocks drops below 2,000 cfs, daily monitoring will be resumed.