This is an aerial view of WSSC’s Broad Creek sewage pumping station that overflowed Wednesday night in Fort Washington. (Courtesy of Washington Suburban Sanitary Commission)

Nearly 1 million gallons of untreated sewage spilled into Broad Creek in Prince George’s County on Wednesday night after heavy rain overwhelmed a sewage pumping station in Fort Washington, a utility spokesman said.

The Washington Suburban Sanitary Commission (WSSC) estimated that about 982,000 gallons flowed into the creek between 8:20 p.m. Wednesday and 12:30 a.m. Thursday. The pumps at the station at 10315 Livingston Rd. worked throughout the storm but were overwhelmed by the volume of water entering the system. WSSC’s sewer system is separate from the storm water run-off system but rain water can still rush into manholes and enter the sewers via leaky pipes, said WSSC spokesman Jerry Irvine.

The sewage overflow does not affect the drinking water supply. WSSC provides water and sewer services to nearly 2 million people in Montgomery and Prince George’s counties.

Like other older sewer utilities, WSSC is under a federal court agreement to reduce the number of sewage spills into local waterways. Irvine said WSSC has a construction project underway to reduce sewage overflows at the Broad Creek pumping station.