Current drought monitoring status:

Daily Monitoring was discontinued on 10/30/2017

Daily Monitoring was recommenced on 10/20/2017

Daily Monitoring was discontinued on 10/13/2017

Daily Monitoring was initiated on 9/19/2017


​​Discontinue Monitoring - Daily Potomac flow and demand update (Monday 2017-10-30)

The National Weather Service (NWS) 24 hour observed precipitation shows that there was between 0.10 and 3.00 inches of precipitation in the Potomac basin above Little Falls. The NWS 3-day and 5-day forecasts both predict 0.00 to 0.25 inches of rain in this same area.

The daily average flow at the US Geological Survey gage at Point of Rocks has been above 2,000 cfs, our trigger for daily monitoring, for the past four days. The NWS Global Ensemble Forecast System simulations predict that flow at Point of Rocks may continue to remain above 2,000 cfs for the week. Therefore, daily monitoring will be discontinued until further notice. Thank you to all for your contribution to the monitoring efforts!

Daily Flows:

Little Falls gage flow 2017-10-29: 1590 MGD (2460 cfs)

Little Falls gage flow 2017-10-30: 2120 MGD (est., based on recently available real time data) (3280 cfs)

Note: Gage flow at Little Falls is measured after water supply withdrawals.

Point of Rocks flow 2017-10-29: 1454 MGD (2250 cfs)

Point of Rocks flow 2017-10-30: 2734 MGD (est., based on recently available real time data) (4230 cfs)

​​Net Potomac withdrawal (2017-10-29):

FW Corbalis withdrawal (Potomac): 77 MGD

WSSC Potomac withdrawal: 132 MGD

Aqueduct withdrawal: 116 MGD

Total Potomac withdrawal: 325 MGD


Daily Potomac flow and demand update (Sunday 2017-10-29)

According to the Middle Atlantic River Forecast Center (MARFC), portions of the basin received no rain or trace amounts over the last 24 hours, and the northwestern edge of the basin received up to 2 inches. Over the next day, MARFC predicts 1 to 1 3/4 inches in the drainage area above Little Falls dam.  Although flow at the US Geological Survey gage at Point of Rocks is currently above 2,000 cfs, our trigger for daily monitoring, we will continue daily monitoring efforts until we see that flows have significantly improved for several days.

Daily Flows:

Little Falls gage flow 2017-10-28: 1590 MGD (2460 cfs)

Little Falls gage flow 2017-10-29: 1551 MGD (est., based on recently available real time data) (2400 cfs)

Note: Gage flow at Little Falls is measured after water supply withdrawals.

Point of Rocks flow 2017-10-28: 1364 MGD (2110 cfs)

Point of Rocks flow 2017-10-29: 1338 MGD (est., based on recently available real time data) (2070 cfs)

Net Potomac withdrawal (2017-10-28):

FW Corbalis withdrawal (Potomac): 148 MGD

WSSC Potomac withdrawal: 133 MGD

Aqueduct withdrawal: 128 MGD

Total Potomac withdrawal: 409 MGD


Daily Potomac flow and demand update (Saturday 2017-10-28)

The National Weather Service (NWS) reports that there was no precipitation in the Potomac basin over the last 24 hours. The NWS 3-day forecast predicts 1.25 to 2.0 inches of rain in the portion of the basin above Little Falls dam.  Although flows at the US Geological Survey gage at Point of Rocks is currently above 2,000 cfs, our trigger for daily monitoring, we will continue daily monitoring efforts until we see that flows have significantly improved for several days.

Daily Flows:

Little Falls gage flow 2017-10-27: 1545 MGD (2390 cfs)

Little Falls gage flow 2017-10-28: 1616 MGD (est., based on recently available real time data) (2500 cfs)

Note: Gage flow at Little Falls is measured after water supply withdrawals.

Point of Rocks flow 2017-10-27: 1370 MGD (2120 cfs)

Point of Rocks flow 2017-10-28: 1564 MGD (est., based on recently available real time data) (2420 cfs)

Net Potomac withdrawal (2017-10-27):

FW Corbalis withdrawal (Potomac): 155 MGD

WSSC Potomac withdrawal: 132 MGD

Aqueduct withdrawal: 127 MGD

Total Potomac withdrawal: 415 MGD


Daily Potomac flow and demand update (Friday 2017-10-27)

The National Weather Service (NWS) 24 hour observed precipitation shows that there were scattered, trace amounts of rain in the Potomac basin above Little Falls. The NWS 3-day forecast predicts 0.75 to 1.5 inches of rain in this same area. The National Weather Service (NWS) 5-day forecast predicts accumulations of up to 2.5 inches of rain in the Potomac basin. Although flows at the US Geological Survey gage at Point of Rocks is currently above 2,000 cfs, our trigger for daily monitoring, we will continue daily monitoring efforts until we see that flows have significantly improved for several days.

Daily Flows:

Little Falls gage flow 2017-10-26: 1474 MGD (2280 cfs)

Little Falls gage flow 2017-10-27: 1487 MGD (est., based on recently available real time data) (2300 cfs)

Note: Gage flow at Little Falls is measured after water supply withdrawals.

Point of Rocks flow 2017-10-26: 1331 MGD (2060 cfs)

Point of Rocks flow 2017-10-27: 1506 MGD (est., based on recently available real time data) (2330 cfs)

Net Potomac withdrawal (2017-10-26):

FW Corbalis withdrawal (Potomac): 84 MGD

WSSC Potomac withdrawal: 116 MGD

Aqueduct withdrawal: 129 MGD

Total Potomac withdrawal: 329 MGD


Daily Potomac flow and demand update (Thursday 2017-10-26)

The National Weather Service (NWS) 24 hour observed precipitation shows that there were scattered, trace amounts of rain in the Potomac basin above Little Falls. The NWS 3-day forecast predicts 0 to 0.5 inches of rain in this same area with the largest amounts expected in the western portions of the basin. The National Weather Service (NWS) 5-day forecast predicts accumulations of up to 1.75 inches of rain in the Potomac basin. Although flows at the US Geological Survey gage at Point of Rocks is currently above 2,000 cfs, our trigger for daily monitoring, we will continue daily monitoring efforts until we see that flows have significantly improved for several days.

Daily Flows:

Little Falls gage flow 2017-10-25: 1512 MGD (2340 cfs)

Little Falls gage flow 2017-10-26: 1428 MGD (est., based on recently available real time data) (2210 cfs)

Note: Gage flow at Little Falls is measured after water supply withdrawals.

Point of Rocks flow 2017-10-25: 1228 MGD (1900 cfs)

Point of Rocks flow 2017-10-26: 1461 MGD (est., based on recently available real time data) (2260 cfs)

Net Potomac withdrawal (2017-10-25):

FW Corbalis withdrawal (Potomac): 85 MGD

WSSC Potomac withdrawal: 125 MGD

Aqueduct withdrawal: 130 MGD

Total Potomac withdrawal: 340 MGD


Daily Potomac flow and demand update (Wednesday 2017-10-25)

The National Weather Service (NWS) 24 hour observed precipitation shows that there was 0.00 to 0.50 inches of rain in the Potomac basin above Little Falls. The NWS 3-day forecast predicts no rain over the majority of this same area. The US Geological Survey shows that Point of Rocks flow fell below and then rose above 2,000 cfs, our trigger for daily monitoring. We will continue daily monitoring efforts until we see that flows have significantly improved for several days.

Daily Flows:

Little Falls gage flow 2017-10-24: 1247 MGD (1930 cfs)

Little Falls gage flow 2017-10-25: 1519 MGD (est., based on recently available real time data) (2350 cfs)

Note: Gage flow at Little Falls is measured after water supply withdrawals.

Point of Rocks flow 2017-10-24: 1202 MGD (1860 cfs)

Point of Rocks flow 2017-10-25: 1338 MGD (est., based on recently available real time data) (2070 cfs)

Net Potomac withdrawal (2017-10-24):

FW Corbalis withdrawal (Potomac): 79 MGD

WSSC Potomac withdrawal: 125 MGD

Aqueduct withdrawal: 135 MGD

Total Potomac withdrawal: 339 MGD


Daily Potomac flow and demand update (Tuesday 2017-10-24)

The National Weather Service (NWS) 24 hour observed precipitation shows that there was 0.01 to 1.25 inches of rain in the Potomac basin above Little Falls. The NWS 3-day forecast predicts accumulations of 0.25 to 1.50 inches of rain over this same area. The US Geological Survey shows that Point of Rocks flow rose above 2,000 cfs, our trigger for daily monitoring. We will continue daily monitoring efforts until we see that flows have significantly improved for several days.

Daily Flows:

Little Falls gage flow 2017-10-23: 1099 MGD (1700 cfs)

Little Falls gage flow 2017-10-24: 1086 MGD (est., based on recently available real time data) (1680 cfs)

Note: Gage flow at Little Falls is measured after water supply withdrawals.

Point of Rocks flow 2017-10-23: 1053 MGD (1630 cfs)

Point of Rocks flow 2017-10-24: 1370 MGD (est., based on recently available real time data) (2120 cfs)

Net Potomac withdrawal (2017-10-23):

FW Corbalis withdrawal (Potomac): 94 MGD

WSSC Potomac withdrawal: 150 MGD

Aqueduct withdrawal: 136 MGD

Total Potomac withdrawal: 380 MGD


Daily Potomac flow and demand update (Monday 2017-10-23)

The National Weather Service (NWS) 24 hour observed precipitation shows that there was 0 inches of rain in the Potomac basin above Little Falls. The NWS 3-day forecast predicts accumulations of 0.50 to 1.25 inches of rain over this same area. The NWS Global Ensemble Forecast System simulations predict that flow at Point of Rocks may rise above 2000 cfs, our trigger for daily drought monitoring, sometime this week.

Daily Flows:

Little Falls gage flow 2017-10-22: 1228 MGD (1900 cfs)

Little Falls gage flow 2017-10-23: 1060 MGD (est., based on recently available real time data) (1640 cfs)

Note: Gage flow at Little Falls is measured after water supply withdrawals.

Point of Rocks flow 2017-10-22: 1028 MGD (1590 cfs)

Point of Rocks flow 2017-10-23: 1034 MGD (est., based on recently available real time data) (1600 cfs)

Net Potomac withdrawal (2017-10-22):

FW Corbalis withdrawal (Potomac): 104 MGD

WSSC Potomac withdrawal: 132 MGD

Aqueduct withdrawal: 125 MGD

Total Potomac withdrawal: 361 MGD


Daily Potomac flow and demand update (Sunday 2017-10-22)

No rain fell in the basin over the past 24 hours. The National Weather Service (NWS) 3-day forecast predicts accumulations of 0.5 to 1 inch of rain across the basin. The NWS 5-day forecast predicts accumulations of up to 1.75 inches of rain in the Potomac basin.

Daily Flows:

Little Falls gage flow 2017-10-21: 1280 MGD (1980 cfs)

Little Falls gage flow 2017-10-22: 1170 MGD (est., based on recently available real time data) (1810 cfs)

Note: Gage flow at Little Falls is measured after water supply withdrawals.

Point of Rocks flow 2017-10-21: 1138 MGD (1760 cfs)

Point of Rocks flow 2017-10-22: 1008 MGD (est., based on recently available real time data) (1560 cfs)

Net Potomac withdrawal (2017-10-21):

FW Corbalis withdrawal (Potomac): 89 MGD

WSSC Potomac withdrawal: 132 MGD

Aqueduct withdrawal: 137 MGD

Total Potomac withdrawal: 358 MGD


Daily Potomac flow and demand update (Saturday 2017-10-21)

No rain fell in the basin over the past 24 hours. Flow at Point of Rocks is currently at about 1900 cfs. The National Weather Service (NWS) 3-day forecast predicts accumulations of 0.01 to 0.10 inches in the western part of the Potomac basin. The NWS 5-day forecast predicts accumulations of up to 1.25 inches of rain in the Potomac basin.

Daily Flows:

Little Falls gage flow 2017-10-20: 1331 MGD (2060 cfs)

Little Falls gage flow 2017-10-21: 1280 MGD (est., based on recently available real time data) (1980 cfs)

Note: Gage flow at Little Falls is measured after water supply withdrawals.

Point of Rocks flow 2017-10-20: 1144 MGD (1770 cfs)

Point of Rocks flow 2017-10-21: 1234 MGD (est., based on recently available real time data) (1910 cfs)

Net Potomac withdrawal (2017-10-20):

FW Corbalis withdrawal (Potomac): 98 MGD

WSSC Potomac withdrawal: 133 MGD

Aqueduct withdrawal: 132 MGD

Total Potomac withdrawal: 363 MGD


Daily Potomac flow and demand update (Friday 2017-10-20)

Flow at Point of Rocks is currently at about 2000 cfs, CO-OP's trigger for daily drought monitoring. No rain fell in the basin over the past 24 hours, and no rain is expected over the next 72 hours, according to the Middle Atlantic River Forecast Center's quantitative precipitation forecasts. The National Weather Service (NWS) 5-day forecast predicts accumulations of up to 1.25 inches of rain in the Potomac basin.

Daily Flows:

Little Falls gage flow 2017-10-19: 1558 MGD (2410 cfs)

Little Falls gage flow 2017-10-20: 1338 MGD (est., based on recently available real time data) (2070 cfs)

Note: Gage flow at Little Falls is measured after water supply withdrawals.

Point of Rocks flow 2017-10-19: 1176 MGD (1820 cfs)

Point of Rocks flow 2017-10-20: 1293 MGD (est., based on recently available real time data) (2000 cfs)

Net Potomac withdrawal (2017-10-19):

FW Corbalis withdrawal (Potomac): 87 MGD

WSSC Potomac withdrawal: 135 MGD

Aqueduct withdrawal: 145 MGD

Total Potomac withdrawal: 367 MGD


Daily Potomac flow and demand update (Friday 2017-10-13)

Point of Rocks flow is at 3110 cfs. Within the last 24 hours, the Potomac basin has received up to 0.1 inches of precipitation. The National Weather Service (NWS) 3-day forecast predicts accumulations of 0.25 inches of rain in the Potomac basin above Little Falls.

With rain continuing to fall across much of the basin, and Point of Rocks flow being above the low flow monitoring threshold of 2,000 cfs, daily monitoring will be discontinued until further notice. Thank you to all for your contribution to the monitoring efforts.

Daily Flows:

Little Falls gage flow 2017-10-12: 1965 MGD (3040 cfs)

Little Falls gage flow 2017-10-13: 1978 MGD (est., based on recently available real time data) (3060 cfs)

Note: Gage flow at Little Falls is measured after water supply withdrawals.

Point of Rocks flow 2017-10-12: 1667 MGD (2580 cfs)

Point of Rocks flow 2017-10-13: 2010 MGD (est., based on recently available real time data) (3110 cfs)

Net Potomac withdrawal (2017-10-12):

FW Corbalis withdrawal (Potomac): 82 MGD

WSSC Potomac withdrawal: 128 MGD

Aqueduct withdrawal: 136 MGD

Total Potomac withdrawal: 345 MGD


Daily Potomac flow and demand update (Thursday 2017-10-12)

The National Weather Service (NWS) 24 hour observed precipitation shows that there was 0.10 to 1.75 inches of rain in the Potomac basin above Little Falls. The NWS 3-day forecast predicts accumulations of 0.01 to 0.75 inches of rain over this same area. The US Geological Survey shows that Point of Rocks flow has remained above 2,000 cfs, our trigger for daily monitoring, since yesterday. The NWS Global Ensemble Forecast System simulations predict that flow at Point of Rocks will continue to rise above 2,000 cfs for the next couple of days. We will continue daily monitoring efforts until we see that flows have significantly improved for several days.

Daily Flows:

Little Falls gage flow 2017-10-11: 1448 MGD (2240 cfs)

Little Falls gage flow 2017-10-12: 1842 MGD (est., based on recently available real time data) (2850 cfs)

Note: Gage flow at Little Falls is measured after water supply withdrawals.

Point of Rocks flow 2017-10-11: 1351 MGD (2090 cfs)

Point of Rocks flow 2017-10-12: 1609 MGD (est., based on recently available real time data) (2490 cfs)

Net Potomac withdrawal (2017-10-11):

FW Corbalis withdrawal (Potomac): 100 MGD

WSSC Potomac withdrawal: 115 MGD

Aqueduct withdrawal: 144 MGD

Total Potomac withdrawal: 359 MGD


Daily Potomac flow and demand update (Wednesday 2017-10-11)

The National Weather Service (NWS) 24 hour observed precipitation shows that there was 0.00 to 0.50 inches of rain in the Potomac basin above Little Falls. The NWS 3-day forecast predicts accumulations of 0.50 to 1.50 inches of rain over this same area. The US Geological Survey shows that Point of Rocks flow has been fluctuating around 2,000 cfs, our trigger for daily monitoring, since yesterday. The NWS Global Ensemble Forecast System simulations predict that flow at Point of Rocks will continue to rise above 2,000 cfs. We will continue daily monitoring efforts until we see that flows have significantly improved for several days.

Daily Flows:

Little Falls gage flow 2017-10-10: 1176 MGD (1820 cfs)

Little Falls gage flow 2017-10-11: 1396 MGD (est., based on recently available real time data) (2160 cfs)

Note: Gage flow at Little Falls is measured after water supply withdrawals.

Point of Rocks flow 2017-10-10: 1267 MGD (1960 cfs)

Point of Rocks flow 2017-10-11: 1383 MGD (est., based on recently available real time data) (2140 cfs)

Net Potomac withdrawal (2017-10-10):

FW Corbalis withdrawal (Potomac): 85 MGD

WSSC Potomac withdrawal: 127 MGD

Aqueduct withdrawal: 137 MGD

Total Potomac withdrawal: 349 MGD


Daily Potomac flow and demand update (Tuesday 2017-10-10)

The National Weather Service (NWS) 24 hour observed precipitation shows that there was 0.00 to 1.50 inches of rain in the Potomac basin above Little Falls. The NWS 3-day forecast predicts accumulations of 0.25 to 1.25 inches of rain over this same area. The NWS Global Ensemble Forecast System simulations predict that flow at Point of Rocks will temporarily rise above 2,000 cfs, our trigger for daily drought monitoring, as earlier as sometime today.

Daily Flows:

Little Falls gage flow 2017-10-09: 1053 MGD (1630 cfs)

Little Falls gage flow 2017-10-10: 1112 MGD (est., based on recently available real time data) (1720 cfs)

Note: Gage flow at Little Falls is measured after water supply withdrawals.

Point of Rocks flow 2017-10-09: 1079 MGD (1670 cfs)

Point of Rocks flow 2017-10-10: 1280 MGD (est., based on recently available real time data) (1980 cfs)

Net Potomac withdrawal (2017-10-09):

FW Corbalis withdrawal (Potomac): 106 MGD

WSSC Potomac withdrawal: 147 MGD

Aqueduct withdrawal: 134 MGD

Total Potomac withdrawal: 386 MGD


Daily Potomac flow and demand update (Monday 2017-10-09)

The National Weather Service (NWS) 24 hour observed precipitation shows that there was 0.25 to 1.75 inches of rain in the Potomac basin above Little Falls. The NWS 3-day forecast predicts accumulations of 0.40 to 1.75 inches of rain over this same area. The NWS Global Ensemble Forecast System simulations predict that flow at Point of Rocks will rise above 2,000 cfs, our trigger for daily drought monitoring, over the coming week.

Daily Flows:

Little Falls gage flow 2017-10-08: 860 MGD (1330 cfs)

Little Falls gage flow 2017-10-09: 957 MGD (est., based on recently available real time data) (1480 cfs)

Note: Gage flow at Little Falls is measured after water supply withdrawals.

Point of Rocks flow 2017-10-08: 840 MGD (1300 cfs)

Point of Rocks flow 2017-10-09: 957 MGD (est., based on recently available real time data) (1480 cfs)

Net Potomac withdrawal (2017-10-08):

FW Corbalis withdrawal (Potomac): 95 MGD

WSSC Potomac withdrawal: 136 MGD

Aqueduct withdrawal: 133 MGD

Total Potomac withdrawal: 363 MGD


Daily Potomac flow and demand update (Sunday 2017-10-08)

According to the Middle Atlantic River Forecast Center's observed precipitation, there was 0.01 to 0.25 inches of precipitation above the Point of Rocks streamflow gage over the last 24 hours. The National Weather Service (NWS) 3-day forecast predicts accumulations of 0.75 to 1.75 inches of rain in the Potomac basin above Little Falls. The NWS Global Ensemble Forecast System simulations predict that flow at Point of Rocks will rise above 2000 cfs, our trigger for daily drought monitoring, over the coming week.

Daily Flows:

Little Falls gage flow 2017-10-07: 866 MGD (1340 cfs)

Little Falls gage flow 2017-10-08: 814 MGD (est., based on recently available real time data) (1260 cfs)

Note: Gage flow at Little Falls is measured after water supply withdrawals.

Point of Rocks flow 2017-10-07: 918 MGD (1420 cfs)

Point of Rocks flow 2017-10-08: 860 MGD (est., based on recently available real time data) (1330 cfs)

Net Potomac withdrawal (2017-10-07):

FW Corbalis withdrawal (Potomac): 104 MGD

WSSC Potomac withdrawal: 136 MGD

Aqueduct withdrawal: 146 MGD

Total Potomac withdrawal: 386 MGD


Daily Potomac flow and demand update (Saturday 2017-10-07)

The National Weather Service (NWS) 3-day forecast predicts accumulations of 1 1/4 to 2 inches of rain in the Potomac basin above Little Falls. The NWS Global Ensemble Forecast System simulations predict that flow at Point of Rocks will rise above 2000 cfs, our trigger for daily drought monitoring, over the coming week.

Daily Flows:

Little Falls gage flow 2017-10-06: 918 MGD (1420 cfs)

Little Falls gage flow 2017-10-07: 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 2017-10-06: 892 MGD (1380 cfs)

Point of Rocks flow 2017-10-07: 879 MGD (est., based on recently available real time data) (1360 cfs)

Net Potomac withdrawal (2017-10-06):

FW Corbalis withdrawal (Potomac): 109 MGD

WSSC Potomac withdrawal: 143 MGD

Aqueduct withdrawal: 157 MGD

Total Potomac withdrawal: 409 MGD


Daily Potomac flow and demand update (Friday 2017-10-06)

The Middle Atlantic Forecast Center forecasts approximately an inch of rain in the basin over the next three days.

Daily Flows:

Little Falls gage flow 2017-10-05: 821 MGD (1270 cfs)

Little Falls gage flow 2017-10-06: 885 MGD (est., based on recently available real time data) (1370 cfs)

Note: Gage flow at Little Falls is measured after water supply withdrawals.

Point of Rocks flow 2017-10-05: 976 MGD (1510 cfs)

Point of Rocks flow 2017-10-06: 918 MGD (est., based on recently available real time data) (1420 cfs)

Net Potomac withdrawal (2017-10-05):

FW Corbalis withdrawal (Potomac): 111 MGD

WSSC Potomac withdrawal: 136 MGD

Aqueduct withdrawal: 145 MGD

Total Potomac withdrawal: 392 M


Daily Potomac flow and demand update (Thursday 2017-10-05)

One to two inches of rain is expected over the next 7 days.

Daily Flows:

Little Falls gage flow 2017-10-04: 840 MGD (1300 cfs)

Little Falls gage flow 2017-10-05: 769 MGD (est., based on recently available real time data) (1190 cfs)

Note: Gage flow at Little Falls is measured after water supply withdrawals.

Point of Rocks flow 2017-10-04: 931 MGD (1440 cfs)

Point of Rocks flow 2017-10-05: 1034 MGD (est., based on recently available real time data) (1600 cfs)

Net Potomac withdrawal (2017-10-04):

FW Corbalis withdrawal (Potomac): 112 MGD

WSSC Potomac withdrawal: 130 MGD

Aqueduct withdrawal: 139 MGD

Total Potomac withdrawal: 381 MGD


Daily Potomac flow and demand update (Wednesday 2017-10-04)

The National Weather Services 7-day quantitative precipitation forecast continues to look promising.

Daily Flows:

Little Falls gage flow 2017-10-03: 808 MGD (1250 cfs)

Little Falls gage flow 2017-10-04: 814 MGD (est., based on recently available real time data) (1260 cfs)

Note: Gage flow at Little Falls is measured after water supply withdrawals.

Point of Rocks flow 2017-10-03: 885 MGD (1370 cfs)

Point of Rocks flow 2017-10-04: 873 MGD (est., based on recently available real time data) (1350 cfs)

Net Potomac withdrawal (2017-10-03):

FW Corbalis withdrawal (Potomac): 107 MGD

WSSC Potomac withdrawal: 136 MGD

Aqueduct withdrawal: 147 MGD

Total Potomac withdrawal: 391 MGD


Daily Potomac flow and demand update (Tuesday 2017-10-03)

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.

Point of Rocks flow 2017-10-02: 847 MGD (1310 cfs)

Point of Rocks flow 2017-10-03: 905 MGD (est., based on recently available real time data) (1400 cfs)

Net Potomac withdrawal (2017-10-02):

FW Corbalis withdrawal (Potomac): 119 MGD

WSSC Potomac withdrawal: 139 MGD

Aqueduct withdrawal: 130 MGD

Total Potomac withdrawal: 388 MGD


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

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)

Net Potomac withdrawal (2017-10-01):

FW Corbalis withdrawal (Potomac): 102 MGD

WSSC Potomac withdrawal: 133 MGD

Aqueduct withdrawal: 137 MGD

Total Potomac withdrawal: 372 MGD


Daily Potomac flow and demand update (Sunday 2017-10-01)

No change in weather conditions is expected over the next week. The US Army Corps of Engineers made the season's final whitewater release yesterday from Savage Reservoir: 1000 cfs from 10 AM to 4 PM. More information on North Branch Potomac releases can be found at http://www.nab-wc.usace.army.mil/northBranch.html.

Daily Flows:

Little Falls gage flow 2017-09-30: 873 MGD (1350 cfs)

Little Falls gage flow 2017-10-01: 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 2017-09-30: 905 MGD (1400 cfs)

Point of Rocks flow 2017-10-01: 879 MGD (est., based on recently available real time data) (1360 cfs)

Net Potomac withdrawal (2017-09-30):

FW Corbalis withdrawal (Potomac): 107 MGD

WSSC Potomac withdrawal: 125 MGD

Aqueduct withdrawal: 142 MGD

Total Potomac withdrawal: 374 MGD


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

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)

Net Potomac withdrawal (2017-09-29):

FW Corbalis withdrawal (Potomac): 108 MGD

WSSC Potomac withdrawal: 139 MGD

Aqueduct withdrawal: 155 MGD

Total Potomac withdrawal: 402 MGD


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

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.

Daily Flows:

Little Falls gage flow 2017-09-28: 918 MGD (1420 cfs)

Little Falls gage flow 2017-09-29: 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 2017-09-28: 969 MGD (1500 cfs)

Point of Rocks flow 2017-09-29: 957 MGD (est., based on recently available real time data) (1480 cfs)

Net Potomac withdrawal (2017-09-28):

FW Corbalis withdrawal (Potomac): 111 MGD

WSSC Potomac withdrawal: 137 MGD

Aqueduct withdrawal: 153 MGD

Total Potomac withdrawal: 401 MGD

Net Potomac withdrawal (2017-09-27):

FW Corbalis withdrawal (Potomac): 123 MGD

WSSC Potomac withdrawal: 125 MGD

Aqueduct withdrawal: 157 MGD

Total Potomac withdrawal: 405 MGD


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

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)

Net Potomac withdrawal (2017-09-26):

FW Corbalis withdrawal (Potomac): 116 MGD

WSSC Potomac withdrawal: 138 MGD

Aqueduct withdrawal: 148 MGD

Total Potomac withdrawal: 402 MGD


Daily Potomac flow and demand update (Tuesday 2017-09-26)

Dry conditions are expected to continue over the next week.

Daily Flows:

Little Falls gage flow 2017-09-25: 1021 MGD (1580 cfs)

Little Falls gage flow 2017-09-26: 957 MGD (est., based on recently available real time data) (1480 cfs)

Note: Gage flow at Little Falls is measured after water supply withdrawals.

Point of Rocks flow 2017-09-25: 1028 MGD (1590 cfs)

Point of Rocks flow 2017-09-26: 1125 MGD (est., based on recently available real time data) (1740 cfs)

Net Potomac withdrawal (2017-09-25):

FW Corbalis withdrawal (Potomac): 123 MGD

WSSC Potomac withdrawal: 144 MGD

Aqueduct withdrawal: 145 MGD

Total Potomac withdrawal: 412 MGD



Daily Potomac flow and demand update (Monday 2017-09-25)

Potomac basin stream flows continue to fall. The 7-day forecast indicates that dry conditions will persist.

Daily Flows:

Little Falls gage flow 2017-09-24: 1138 MGD (1760 cfs)

Little Falls gage flow 2017-09-25: 1034 MGD (est., based on recently available real time data) (1600 cfs)

Note: Gage flow at Little Falls is measured after water supply withdrawals.

Point of Rocks flow 2017-09-24: 1021 MGD (1580 cfs)

Point of Rocks flow 2017-09-25: 1021 MGD (est., based on recently available real time data) (1580 cfs)

Net Potomac Production (2017-09-24):

FW Corbalis raw water withdrawal (Potomac): 106 MGD

WSSC Potomac Production: 119 MGD

Aqueduct withdrawal: 140 MGD

Total Potomac demand: 364 MGD


Daily Potomac flow and demand update (Sunday, 2017-09-24)

The Middle Atlantic River Forecast Center (MARFC) predicts no rain in the basin over the next 3 days.

Daily Flows:

Little Falls gage flow 2017-09-23: 1222 MGD (1890 cfs)

Little Falls gage flow 2017-09-24: 1144 MGD (est., based on recently available real time data) (1770 cfs)

Note: Gage flow at Little Falls is measured after water supply withdrawals.

Point of Rocks flow 2017-09-23: 1105 MGD (1710 cfs)

Point of Rocks flow 2017-09-24: 1034 MGD (est., based on recently available real time data) (1600 cfs)

Net Potomac Production (2017-09-23):

FW Corbalis raw water withdrawal (Potomac): 105 MGD

WSSC Potomac Production: 142 MGD

Aqueduct withdrawal: 143 MGD

Total Potomac demand: 390 MGD


Daily Potomac flow and demand update (Saturday 2017-09-23)

Stream flows in the Potomac basin continue to slowly decline. The National Weather Service (NWS) quantitative prediction forecast indicates that less than 1/10 inch of rain will fall in the basin over the next seven day period.

Daily Flows:

Little Falls gage flow 2017-09-22: 1351 MGD (2090 cfs)

Little Falls gage flow 2017-09-23: 1254 MGD (est., based on recently available real time data) (1940 cfs)

Note: Gage flow at Little Falls is measured after water supply withdrawals.

Point of Rocks flow 2017-09-22: 1189 MGD (1840 cfs)

Point of Rocks flow 2017-09-23: 1163 MGD (est., based on recently available real time data) (1800 cfs)

Net Potomac Production (2017-09-22):

FW Corbalis raw water withdrawal (Potomac): 120 MGD

WSSC Potomac Production: 125 MGD

Aqueduct withdrawal: 143 MGD

Total Potomac demand: 387 MGD


Daily Potomac flow and demand update (Friday 2017-09-22)

The 7-day forecast calls for dry conditions throughout the Potomac basin. Flows in the river are at typical levels for this time of year.

Daily Flows:

Little Falls gage flow 2017-09-21: 1293 MGD (2000 cfs)

Little Falls gage flow 2017-09-22: 1338 MGD (est., based on recently available real time data) (2070 cfs)

Note: Gage flow at Little Falls is measured after water supply withdrawals.

Point of Rocks flow 2017-09-21: 1377 MGD (2130 cfs)

Point of Rocks flow 2017-09-22: 1280 MGD (est., based on recently available real time data) (1980 cfs)

Net Potomac Production (2017-09-21):

FW Corbalis raw water withdrawal (Potomac): 107 MGD

WSSC Potomac Production: 119 MGD

Aqueduct withdrawal: 139 MGD

Total Potomac demand: 364 MGD


Daily Potomac flow and demand update (Thursday 2017-09-21)

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.

Point of Rocks flow 2017-09-20: 1325 MGD (2050 cfs)

Point of Rocks flow 2017-09-21: 1506 MGD (est., based on recently available real time data) (2330 cfs)

Net Potomac Production (2017-09-20):

FW Corbalis raw water withdrawal (Potomac): 109 MGD

WSSC Potomac Production: 145 MGD

Aqueduct withdrawal: 139 MGD

Total Potomac demand: 393 MGD


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

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.

Point of Rocks flow 2017-09-19: 1247 MGD (1930 cfs)

Point of Rocks flow 2017-09-20: 1351 MGD (est., based on recently available real time data) (2090 cfs)

Net Potomac Production (2017-09-19):

FW Corbalis raw water withdrawal (Potomac): 106 MGD

WSSC Potomac Production: 146 MGD

Aqueduct withdrawal: 145 MGD

Total Potomac demand: 397 MGD


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

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.

The US Army Corps of Engineers made two "artificially varied flow" releases, each of over 1000 cfs and of approximately 12 hour duration, last Saturday and Sunday, Sep 16 and 17. These releases are currently visible at the USGS gage at Hancock.

Daily Flows:

Little Falls gage flow 2017-09-18: 1254 MGD (1940 cfs)

Little Falls gage flow 2017-09-19: 1280 MGD (est., based on recently available real time data) (1980 cfs)

Note: Gage flow at Little Falls is measured after water supply withdrawals.

Point of Rocks flow 2017-09-18: 1260 MGD (1950 cfs)

Point of Rocks flow 2017-09-19: 1306 MGD (est., based on recently available real time data) (2020 cfs)

Net Potomac Production (2017-09-18):

FW Corbalis raw water withdrawal (Potomac): 108 MGD

WSSC Potomac Production: 139 MGD

Aqueduct withdrawal: 149 MGD

Total Potomac demand: 396 MGD