As late summer and early fall approaches, there is good news about the D.C. area’s water supply.
The Interstate Commission on the Potomac River Basin said there is a below normal probability of needing to release backup water supplies from area reservoirs. In the commission’s latest update, it said “there is a minimal, less than 1% to 2% conditional probability that natural Potomac flow will drop below 600 to 700 million gallons per day at Little Falls through December 31, 2025.”
Above average rainfall in the area in May, June and July is contributing to the positive outlook and resulted in the drought watch for our area being dropped in late June, after being in place for more than a year.
The commission also said groundwater levels are stable or rising, and major reservoirs are near full capacity.
More good news, the seasonal outlook calls for a continued likelihood of above-normal rainfall. If that forecast is not accurate, the commission said it’s ready for that contingency.
“If dry conditions were to develop, the region remains well prepared with carefully designed drought contingency plans and coordinated reservoir operations.”
Despite this optimistic outlook, drought conditions in the D.C. area can’t be ruled out in the future, and are being driven by many factors including one called hot drought. That happens when rising temperatures couple with the natural variability in precipitation.
There have also been discussions in the last year about finding alternative water supplies for the area. The U.S. Army Corps of Engineers is set to begin a three-year feasibility study of ways to bolster the resilience of the area’s water supply.
D.C. and its Virginia and Maryland suburbs are dependent on the Potomac River as the main — or sole — source of drinking water, with only a one-or-two-day supply of drinking water if the Potomac became contaminated, or otherwise unavailable.
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