DC Health lifts Potomac River advisory after 21 days of safe tests

DC Health lifted the recreational advisory for the Potomac River within Washington, D.C., on March 2 after repeated water-quality tests showed bacterial levels, including E. coli, met federal recreational standards for 21 consecutive days. The decision clears the way for most boating and fishing in District waters, though officials cautioned residents to stay vigilant near the site of the January spill and said swimming remains prohibited without special permission.

The advisory followed a catastrophic collapse of a section of the Potomac Interceptor sewer on Jan. 19 that released "millions of gallons of untreated wastewater" into the river. DC Water, the operator of the interceptor, began daily bacterial testing of the river on Jan. 29 and has continued monitoring multiple locations in coordination with other agencies since then. Officials said the readings over the last three weeks stayed within a typical range for the District and met Environmental Protection Agency recreational standards, which assess E. coli at a threshold of 410 MPN per 100 mL.

"Protecting the health and safety of District residents is our top priority," Dr. Ayanna Bennett, director of DC Health, said in announcing the lift. "After careful review of the last three weeks of water quality data, we are confident that conditions in the District’s portion of the Potomac River no longer pose an elevated public health risk. This advisory applies only to waters within the District of Columbia, and we encourage residents to follow guidance from neighboring jurisdictions for areas outside the District’s boundaries."

DC Water said it expects to repair the collapsed section and restore normal flow by mid-March. The utility also plans environmental restoration along the drainage channel, the C&O Canal, and the Potomac shoreline out to Swainson Island once repairs are complete. Officials emphasized that the District’s municipal drinking water supply was not affected by the collapse because drinking water intakes are located upstream and opposite the direction of the sewage flow.

With the advisory lifted, District guidance permits boating and fishing in the city's portion of the Potomac, but swimmers should note that swimming in the Potomac within D.C. remains restricted unless a special permission is granted. Health authorities urged people to avoid direct contact with discolored water and to take extra care after rain or snowmelt, which can stir up runoff and cause bacterial levels to fluctuate.

Public response has been mixed. Local officials and the mayor’s office highlighted the lift of the advisory, but some residents said they were still uneasy about returning to the river for recreation.

Officials said they will continue routine testing and urged anyone who recreates on the river to follow posted notices and guidance from neighboring Maryland and Virginia authorities for waters outside the District. Key unanswered items remain, including a precise accounting of the total volume spilled and detailed timelines for all restoration work; officials said those details will be provided as repairs and assessments continue.