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 (Thursday 2017-09-21)

Submitted by admin1 on Thu, 09/21/2017 - 09:00

Flow at Point of Rocks is currently elevated because of two water quality releases made by the Corps last weekend from Jennings Randolph Reservoir. NWS forecasts indicate that dry conditions will persist for the next week.

Daily Flows:
Little Falls gage flow 2017-09-20: 1260 MGD (1950 cfs)
Little Falls gage flow 2017-09-21: 1254 MGD (est., based on recently available real time data) (1940 cfs)
Note: Gage flow at Little Falls is measured after water supply withdrawals.

Daily Potomac flow and demand update (Wednesday 2017-09-20)

Submitted by admin1 on Wed, 09/20/2017 - 09:00

Flow at Point of Rocks is currently at about 2000 cfs, CO-OP's trigger for daily drought monitoring. But the likely cause of this rise in flow is the Corps' AVF release on Saturday, Sep 16th. National Weather Service (NWS) forecasts indicate that dry conditions will continue in the basin for the next 7 days.

Daily Flows:
Little Falls gage flow 2017-09-19: 1267 MGD (1960 cfs)
Little Falls gage flow 2017-09-20: 1280 MGD (est., based on recently available real time data) (1980 cfs)
Note: Gage flow at Little Falls is measured after water supply withdrawals.

Daily Potomac flow and demand update (Tuesday 2017-09-19)

Submitted by admin1 on Tue, 09/19/2017 - 09:00

Potomac River flow at Point of Rocks is hovering around 2000 cfs, the trigger for CO-OP daily drought monitoring. It should be noted that flows in the river are not particularly low for this time of year - 2000 cfs is close to the median flow at Point of Rocks in mid-September. The National Weather Service forecast calls for little rain over the next seven days.

DROUGHT EXERCISE - Afternoon Potomac flow and demand update (Wednesday 8/13/2017) - DROUGHT EXERCISE

Submitted by admin1 on Sun, 08/13/2017 - 14:00

This concludes the 2017 Washington Metropolitan Area (WMA) Drought Exercise - thank you for your support of WMA drought preparedness!
Actual daily drought monitoring continues, so suppliers please continue to submit your withdrawal data every morning.

DROUGHT EXERCISE - Afternoon Potomac flow and demand update (Wednesday 8/13/2017) - DROUGHT EXERCISE
NOTE: In our twice daily reports for the 2017 exercise we will be reporting ACTUAL basin flows and system withdrawals, and SIMULATED recommended operations.

Daily Potomac flow and demand update (Saturday 09/10/2016)

Submitted by admin1 on Sat, 09/10/2016 - 09:00

Over the past 24 hours, accumulations of rain of up to an inch were recorded in scattered areas, in the northwestern portion of the basin. According to the Middle Atlantic River Forecast Center's quantitative precipitation forecasts, between zero and 1/2 of an inch is expected over the next 72 hours, mainly in the northern portion of the basin.

Daily Potomac flow and demand update (Saturday 09/26/2015)

Submitted by admin1 on Sat, 09/26/2015 - 09:00

A limited area in southwestern portion of the basin received a half to one inch of rain over the past 24 hours. Other areas in the southern half of the basin received up to a quarter of an inch. Accumulated rainfall predictions over the next three days remain the greatest to the south. Today's prediction ranges from 0.01 to 0.75 inches.

A white water release has begun from Savage Reservoir. It will conclude early this evening.

Daily Potomac flow and demand update (Friday 09/25/2015)

Submitted by admin1 on Fri, 09/25/2015 - 09:00

A negligible amount of rain fell in the basin yesterday. MARFC continues to show some chance of rain through the weekend. Between 0.01 and 0.50 inches are possible today in the southern portion of the basin. The chance of rain extends north on Saturday and Sunday. Accumulated rainfall may reach 1.50 inches to the south. The northern areas may see a 3-day accumulation between 0.10 and 0.50 inches.

Last weekend's artificially varied flow release is now passing Little Falls.