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 (Friday, 2024-07-26)

Submitted by aseck on Fri, 07/26/2024 - 12:08

Situational Awareness (Friday, 2024-07-26)

A small amount of rain fell on the basin yesterday. Flow at the Little Falls gage has peaked and begun to recede. No rain is expected over the next 3 days, with a basin rainfall average of approximately 0.4 inches predicted for the next 7 days.

Special Conditions

None

Recent basin-wide average precipitation (above Little Falls):

Daily Potomac flow and demand update (Thursday, 2024-07-25)

Submitted by aseck on Thu, 07/25/2024 - 00:12

Situational Awareness (Thursday, 2024-07-25)
The recent rain has provided temporary relief to low river flows. Yesterday,  flow at the Point of Rocks gage rose above 2000 cfs before receding and is currently at about 1840 cfs. Flow at the Little Falls gage has begun to rise and is expected to recede over the coming days. Limited rain is in the forecast. A basin average rainfall of about 0.4 inches is expected over the next 7 days, with 0.1 inches anticipated over the next 3 days.
                            
Special Conditions

Daily Potomac flow and demand update (Wednesday, 2024-07-24)

Submitted by hmoltz on Wed, 07/24/2024 - 12:26

Situational Awareness (Wednesday, 2024-07-24)
Flows have been rising overnight at the Point of Rocks gage due to recent rain. According to the Middle Atlantic River Forecast Center, the next 24 hours may see 0.2 inches of rain. Over the next 3 days, the average basin rainfall is expected to be around 0.4 inches. 

Special Conditions
None

Daily Potomac flow and demand update (Tuesday, 2024-07-23)

Submitted by snummer on Tue, 07/23/2024 - 12:22

Situational Awareness (Tuesday, 2024-07-23)
Just over 0.4 inches of rain fell across the basin yesterday. According to the Middle Atlantic River Forecast Center predictions, the next 24 hours may see 0.3 inches of rain. Over the next 3 days, the average basin rainfall may be around 0.6 inches. 

Special Conditions
None

Daily Potomac flow and demand update (Monday, 2024-07-22)

Submitted by hmoltz on Mon, 07/22/2024 - 12:16

Situational Awareness (Monday, 2024-07-22)
Trace amounts of rain fell in scattered areas of the basin yesterday.  According to the Middle Atlantic River Forecast Center, up to an inch of rain is possible over the next 24 hours. The average basin rainfall for the next 3 days may be around 1.5 inches. 

Special Conditions
None

Daily Potomac flow and demand update (Sunday, 2024-07-21)

Submitted by admin1 on Sun, 07/21/2024 - 11:55

Situational Awareness (Sunday, 2024-07-21)
Rainfall yesterday in the Potomac basin was scattered. Potomac River flows at Point of Rocks have been relatively steady over the past few days. The Middle Atlantic River Forecast Center predicts little rain in the basin over the next day and an average of 0.6 inches over the next three days.

Daily Potomac flow and demand update (Saturday, 2024-07-20)

Submitted by snummer on Sat, 07/20/2024 - 14:24

Situational Awareness (Saturday, 2024-07-20)
No appreciable rainfall has fallen in the basin over the past 24 hours. According to the Middle Atlantic River Forecast Center predictions, the next 24 hours may see 0.1 inches of rain and the next three days may see about 0.2 inches of rain. The week-long outlook expects a total of approximately 1 inch of rain in the basin.

Daily Potomac flow and demand update (Friday, 2024-07-19)

Submitted by admin1 on Fri, 07/19/2024 - 12:49

Situational Awareness (Friday, 2024-07-19)
Dry conditions persist and Potomac basin stream flows continue to decline. According to the Middle Atlantic River Forecast Center, the Potomac watershed above Little Falls is expected to receive no precipitation over the next day, 0.2 inches over the next 3 days, and 1.1 inches over the next week.

Special Conditions

Daily Potomac flow and demand update (Wednesday, 2024-07-17)

Submitted by admin1 on Wed, 07/17/2024 - 08:19

Situational Awareness (Wednesday, 2024-07-17)
Stream flows throughout the Potomac basin are continuing to decline. Flows in some major Potomac River tributaries have fallen below historic minimums for this day of the year – notably in the South Branch Potomac River near Springfield, WV, and the Shenandoah River at Millville, WV. According to the Middle Atlantic River Forecast Center predictions, 0.4 inches of rain is expected in the basin over the next day and 0.6 inches over the next 3 days.