A 10-foot-deep sinkhole appeared Friday on the George Washington Memorial Parkway. (National Park Service)

One of two northbound lanes of the George Washington Memorial Parkway reopened Tuesday after a 10-foot-deep sinkhole appeared in the road Friday. But officials warned that future lane closures are planned on both sides of the parkway as long-term repairs continue.

The northbound lanes had been closed between the Chain Bridge Road interchange and the Capital Beltway since Friday evening after a U.S. Park Police officer found the sinkhole. National Park Service officials had said rain slowed repair work and they expected one lane to reopen before Tuesday’s evening rush.

The left lane opened around 1 p.m. Tuesday, although it wasn’t known when the right lane would reopen. The southbound lanes were open through the duration of the repairs.

Officials said they worked with the Federal Highway Administration to “inject grout to stabilize soil,” a process during which the grout works like foam to fill gaps in the soil. The sinkhole measured about 30 feet long and 20 feet wide.

Park Service officials said repairs will allow vehicles to travel in the left northbound lane while work is done to design a long-term fix for the right lane. FHA engineers and Park Service crews will monitor the road for any signs of deterioration.

Engineers identified the cause of Friday’s sinkhole as leakage around “a brick inlet that drains water from the road,” but said repairs are difficult because the area is particularly deep.

Officials said a fix will require closing both the northbound and southbound lanes for repairs, although officials haven’t determined when the work will occur.

“As a critical link in the region’s transportation network, closing the George Washington Memorial Parkway is never a decision the National Park Service makes lightly,” the agency said in a statement.

The parkway has had other sinkhole troubles this year. In March, a 10-foot-deep sinkhole opened near Turkey Run after an underground storm water pipe broke.