A broken sewer pipe roughly 8 miles from the White House discharged an estimated 243 million gallons of wastewater into the Potomac River, officials say. The collapse occurred on January 19 in Montgomery County, Md., near the Chesapeake and Ohio Canal.
DC Water reported that most of the spill — about 368 Olympic-sized swimming pools worth — happened in the first five days before crews brought interim bypass pumping online to route sewage around the damaged section. The agency estimated peak discharge at about 40 million gallons per day, roughly 2% of the Potomac’s flow at the time.
Workers discovered a large internal blockage described as a “rock dam” of boulders and debris inside the ruptured pipe. Removing that obstruction will require heavy machinery, manual labor and additional equipment being brought in from Florida and Texas. DC Water estimates blockage removal will take four to six weeks; officials say they cannot set a full repair timeline until the obstruction is cleared and the pipe’s condition is assessed.
Until permanent repairs are finished, DC Water warns there remains a residual risk of limited overflows, though those are expected to be minimal. The authority also says that since February 1, E. coli concentrations downstream of the collapse have been within the U.S. Environmental Protection Agency’s acceptable range for primary-contact recreational activities.
Clean-water advocates have urged stronger public warnings. Betsy Nicholas, president of the Potomac Riverkeeper Network, said the river is not safe, citing collaborative testing with University of Maryland researchers that found samples taken nine days after the collapse contained fecal bacteria levels more than 2,700 times the safe limit used by Maryland and Virginia.
DC Water continues repairs and monitoring while officials weigh public messaging and next steps as cleanup and restoration proceed.