The sinkhole on southbound Interstate 270 in Gaithersburg, Maryland, is going to take a lot longer to fix than first expected.
The Maryland State Highway Administration’s Charlie Gischlar said it could take two weeks to get all lanes reopened, after replacing a damaged drainage pipe that caused the 20-by-30 foot sinkhole to open up June 15 in the far-right lane, north of the I-270 interchange.
“We’re hoping we can get it open by the Fourth of July holiday, if not sooner,” said Gischlar. “There’s a lot of work that still has to be done.”
Gischlar said the replacement pipe should be at the work site Wednesday.
“Then they’re going to work on getting the collar, and replacing that section of pipe that was damaged and led to the erosion,” said the spokesman. “Then we’ve got to put in small white stone, and then the soil, and let it compact.”
Repairing the pipe, then stabilizing the area that will support a road surface capable of carrying thousands of cars daily takes some time.
“You can’t just go in there, replace the pipe and then open everything up,” said Gischlar. “It has to be stable, so you’re not going back there in a few months, doing the same thing to the drivers out there.”
Weather will play a role in how soon all lanes will reopen to commuters, Gischlar said.
“Looks like we’re up to two weeks away from doing that,” he said. “We’re expecting some pretty serious rains (on Wednesday night), so we have to take that into consideration — so, we’re saying up to two weeks.”
Two lanes were shut down on the highway. The construction area, which was initially cordoned off by cones, now has a concrete structure to protect workers.
With school out of session, lower traffic volume and driver awareness is helping minimize delays.
In an aim to alleviate traffic congestion, Montgomery County traffic officials adjusted traffic signal timing on nearby Md. Route 355, which runs parallel to the interstate.
“They were good enough to give a little bit more green time to the through-traffic to southbound traffic, and that’s helping,” said Gischlar. “And a lot of folks are just using their own alternate routes that they take whenever there’s an incident on I-270.”
Below is a map of the area:
WTOP’s Scott Gelman contributed to this story.
