All northbound lanes of 14th Street between L Street and Thomas Circle in Northwest D.C. are closed because D.C. Water said an abandoned, century‑old sewer tunnel beneath the roadway is at risk of collapsing.
“We had a watermain break in the area some time ago, and at that time we discovered this century-old, brick-lined sewer tunnel had not been filled 50 years ago when it was abandoned,” said Sherri Lewis, a spokesperson for D.C. Water.
The road was shut down early Saturday as a precaution.
“For public safety it was important that we get this road closed,” Lewis said. “We couldn’t have heavy vehicles riding over it.”
Engineers deployed cameras into the structure and found a 70-inch crack along the top of the old tunnel. If the tunnel were to collapse, it could lead the road above it to sink.
To avoid that, the plan is to carefully fill the old 42-inch sewer tunnel with a special engineered material that will help support the road and reduce any further risk.
The work needs skilled crews and specialized equipment, and it’s expected to take a few days.
D.C. Water hopes to begin the work by midweek when temperatures are expected to be more accommodating for this type of repair. The utility company is aiming to get the lanes back open by the end of the week.
In the meantime, detours are in place and northbound drivers are being directed to use 13th or 15th streets.
The utility said pedestrian access is being maintained where it is safe.
Southbound lanes on 14th Street remain open.