Potomac River seeing “unusual dryness” the last few months

by Kate Shunney

The Interstate Commission on the Potomac River Basin issues monthly water supply reports on the Potomac River’s water supply for the DC Metro area and general conditions for the length of the river.

Their July 6 and July 12 “Water Supply Outlook” reports that in the Washington metropolitan area, the Com- mission anticipates a higher likelihood of water releases from the backup reservoirs during the summer and fall of 2023.

“Despite receiving some relief from heavy rains, the Potomac basin has experienced unusual dryness over the past few months, resulting in ongoing challenges with low stream flows, groundwater, and soil moisture,” the Commission reports. “Notably, July 4th marked the hottest day ever recorded on Earth, underscoring the necessity of regular reassessment of the current conditions.”

The Potomac River “currently satisfies the region’ s demands” but the Interstate Commission says “comprehensive contingency plans have been established to prevent shortages in the event of low-flow conditions.”

Potomac River conditions are visibly low, as river watchers have observed.

The current river flow is similar to the median for this time of year. But the Potomac River area still experiencing the impact of a dry winter and spring.

Potomac River in Hancock. photo by Geoff Fox

The 90-day precipitation remains low at two inches below average.

The U.S. Geological Survey graph showing the current flow flush with the median flow at Point of Rocks is “only telling part of the story.”

“The northern half of Maryland has been placed under a Drought Watch due to low groundwater levels. The gap between current precipitation and the average precipitation is shrinking, but not very quickly. Much of the basin continues to be in moderate or severe drought status, according to the National Drought Mitigation Center,” the Commission reports.

The Potomac River flow was 3410 cubic feet per second (cfs) at the time of their analysis. Median flow for that same period is 3410 cfs.

Low but still strong

Even when the river flow is low, there are areas that can look calm but are still treacherous, the Commission reminds the public. Unfortunately, drownings happen every year in the Potomac. Stay smart and safe by wearing a personal flotation device.