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 (Tuesday 2017-10-03)

Submitted by admin1 on Tue, 10/03/2017 - 09:00

The National Weather Service's 7-day quantitative precipitation forecast indicates that the basin could receive 1/2 inch to 1 inch of rain at the beginning of next week.

Daily Flows:
Little Falls gage flow 2017-10-02: 827 MGD (1280 cfs)
Little Falls gage flow 2017-10-03: 814 MGD (est., based on recently available real time data) (1260 cfs)
Note: Gage flow at Little Falls is measured after water supply withdrawals.

Daily Potomac flow and demand update (Monday 2017-10-02)

Submitted by admin1 on Mon, 10/02/2017 - 09:00

River flows continue to fall. It looks like the western portion of the basin could receive some rain toward the end of the next 7-day period.

Daily Flows:
Little Falls gage flow 2017-10-01: 873 MGD (1350 cfs)
Little Falls gage flow 2017-10-02: 840 MGD (est., based on recently available real time data) (1300 cfs)
Note: Gage flow at Little Falls is measured after water supply withdrawals.

Point of Rocks flow 2017-10-01: 892 MGD (1380 cfs)
Point of Rocks flow 2017-10-02: 834 MGD (est., based on recently available real time data) (1290 cfs)

Daily Potomac flow and demand update (Saturday 2017-09-30)

Submitted by admin1 on Sat, 09/30/2017 - 09:00

The National Weather Service forecasts that dry conditions will continue in the basin over the next 7 days.

Daily Flows:
Little Falls gage flow 2017-09-29: 853 MGD (1320 cfs)
Little Falls gage flow 2017-09-30: 860 MGD (est., based on recently available real time data) (1330 cfs)
Note: Gage flow at Little Falls is measured after water supply withdrawals.

Point of Rocks flow 2017-09-29: 944 MGD (1460 cfs)
Point of Rocks flow 2017-09-30: 918 MGD (est., based on recently available real time data) (1420 cfs)

DROUGHT EXERCISE - Afternoon simulated Potomac flow and demand update (Tuesday 09/29/2017) - DROUGHT EXERCISE

Submitted by admin1 on Fri, 09/29/2017 - 14:00

This email concludes CO-OP's 2015 Washington Metropolitan Area Drought Exercise. Experience gained during our annual drought exercises helps maintain our region's preparedness to reliably supply water even in the face of serious drought. We would like to thank everyone who participated in the exercise for your assistance, insights, patience, and hard work.

Daily Potomac flow and demand update (Friday 2017-09-29)

Submitted by admin1 on Fri, 09/29/2017 - 09:00

National Weather Service forecasts indicates that the basin will have no relief from the dry weather over the next week. Potomac River flow at Point of Rocks is now close to its 25th percentile level for this day of the year.

The daily flow and demand update was inadvertently not sent out yesterday. Yesterday's reported demand values appear at the end of today's report.

DROUGHT EXERCISE - Afternoon simulated Potomac flow and demand update (Monday 09/28/2017) - DROUGHT EXERCISE

Submitted by admin1 on Thu, 09/28/2017 - 14:00

DROUGHT EXERCISE - Afternoon simulated Potomac flow and demand update (Monday 09/28/2017) - DROUGHT EXERCISE

Daily Flows (simulated):
Little Falls gage flow 09/27: 140 MGD (210 cfs)
Point of Rocks gage flow 09/27: 390 MGD (610 cfs)
Note: Gage flow at Little Falls is measured after water supply withdrawals.
Little Falls gage flow 09/28: 140 MGD (210 cfs)
Point of Rocks gage flow 09/28: 400 MGD (620 cfs)

DROUGHT EXERCISE - Afternoon simulated Potomac flow and demand update (Sunday 09/27/2017) - DROUGHT EXERCISE

Submitted by admin1 on Wed, 09/27/2017 - 14:00

DROUGHT EXERCISE - Afternoon simulated Potomac flow and demand update (Sunday 09/27/2017) - DROUGHT EXERCISE

Daily Flows (simulated):
Little Falls gage flow 09/26: 190 MGD (300 cfs)
Point of Rocks gage flow 09/26: 420 MGD (650 cfs)
Note: Gage flow at Little Falls is measured after water supply withdrawals.
Little Falls gage flow 09/27: 120 MGD (180 cfs)
Point of Rocks gage flow 09/27: 400 MGD (630 cfs)

Daily Potomac flow and demand update (Wednesday 2017-09-27)

Submitted by admin1 on Wed, 09/27/2017 - 09:00

Forecasts indicate that dry conditions will continue for at least the next 7 days.

Daily Flows:
Little Falls gage flow 2017-09-26: 969 MGD (1500 cfs)
Little Falls gage flow 2017-09-27: 982 MGD (est., based on recently available real time data) (1520 cfs)
Note: Gage flow at Little Falls is measured after water supply withdrawals.

Point of Rocks flow 2017-09-26: 1079 MGD (1670 cfs)
Point of Rocks flow 2017-09-27: 1034 MGD (est., based on recently available real time data) (1600 cfs)

DROUGHT EXERCISE - Afternoon simulated Potomac flow and demand update (Saturday 09/26/2017) - DROUGHT EXERCISE

Submitted by admin1 on Tue, 09/26/2017 - 14:00

DROUGHT EXERCISE - Afternoon simulated Potomac flow and demand update (Saturday 09/26/2017) - DROUGHT EXERCISE

Daily Flows (simulated):
Little Falls gage flow 09/25: 180 MGD (280 cfs)
Point of Rocks gage flow 09/25: 380 MGD (590 cfs)
Note: Gage flow at Little Falls is measured after water supply withdrawals.
Little Falls gage flow 09/26: 130 MGD (190 cfs)
Point of Rocks gage flow 09/26: 370 MGD (580 cfs)