More than 5 million gallons of untreated wastewater gushed into Broad Creek, near Fort Washington, Maryland, on Friday.
The overflow occurred at the Broad Creek Wastewater Pumping Station at about 11:15 a.m. Friday, Washington Suburban Sanitary Commission said in a statement. The water utility stopped the flow more than 12 hours later, at about 11:35 p.m.
About 5.22 million gallons of untreated wastewater flowed into the creek, which goes into the Potomac River. Crews cleaned up the affected area and used lime to try to fight the odor.
Residents were advised to avoid the area.
WSSC's water and wastewater systems are separate, and WSSC's drinking water is not affected, the utility's statement said.
WSSC will investigate what caused the overflow. According to the preliminary investigation, a pipe buried about 30 feet deep at the station may have failed.