Officials with D.C. Water are on the scene of a water main break in Southeast Washington.

The 12-inch water main broke early Sunday, near the confluence of Benning Road and Southern Avenue, Water officials said. By 4:30 p.m., officials said crews were expected to complete work to repair the water main by around 10 p.m. Sunday.

The median age of water mains in the District is 77 years, D.C. water officials said, and some sewer pipes in the city date to the civil war.

The District is working to replace all water mains in the city, but the project will take more than a century. D.C. Water is replacing about 1 percent of the city’s water mains per year, which is a faster rate than comparable water agencies, officials said.