A sewer main break at a wastewater treatment plant forced more than 1 million gallons of water to overflow at the Prince George’s County facility, a spokeswoman said Thursday.

A pressurized sewer main at the plant ruptured at about 1:40 p.m. Thursday, said Lyn Riggins, a spokeswoman for the Washington Suburban Sanitary Commission. The break, which happened at the Piscataway Wastewater Treatment Plant in Accokeek, Md., and the overflow of water does not affect drinking water, Riggins said.

The plant – on Farmington Road – is one of several wastewater treatment plants operated by Washington Suburban Sanitary Commission in the D.C. region. The commission provides water and sewer services for communities in the area, including Prince George’s County and Montgomery County.

Riggins said the water overflow is on plant grounds. Crews will dig to locate the break and make repairs. But while they do, water will continue to come in. She said that early calculations show that the overflow has exceeded 1 million gallons and that number will continue to grow.

“We can’t stop it,” Riggins said. “You can’t stop the wastewater from going – it has to go somewhere. It’s going to keep flowing and we will work around the clock until we get equipment in place.”

What kind of equipment? Temporary pipes that will divert the overflow to retention basins, she said.

Riggins added that the overflow is being carefully monitored. Signs are posted in the area of the overflow along Piscataway Creek, she said, and once it stops the commission will “take all appropriate measures to clean up the impacted area.”