The work is taking so long because workers digging down to the sewer line have to navigate a complex thicket of utility lines and old trolley tracks, according to George S. Hawkins, general manager of the D.C. Water and Sewer Authority.
“It’s been the most complicated street repair I’ve seen since I’ve been on the job,” Hawkins said at a news conferencein front of the sinkhole.
Work at the pit could cost nearly $2 million, Hawkins said.
All of the work should be completed and the roads reopened by Friday, said Paul A. Quander Jr., the deputy mayor for public safety.
“A lot of progress has been made,” Quander said. ”We’ve been working around the clock to fix this.”
Northbound 14th Street remains blocked between Pennsylvania and New York avenues, while F Street is closed between 13th and 15th streets. Only southbound traffic can pass through the intersection.
If the roads do reopen Friday, the intersection will have been at least partially blocked for 10 days spanning two work weeks and a holiday weekend. Traffic was severely affected in the blocks around the closure, with cars and buses being diverted from a key artery in and out of the city.
While the cause of the sinkhole is still being investigated, Hawkins said it appears that the hole developed because a nearby manhole was blocking a storm drain.
The storm drain at the northwest corner of the intersection, in front of the Hamilton restaurant, is meant to funnel storm water into the sewer system. But a manhole was constructed that blocked the drain. As a result, water had nowhere to go and seeped into the dirt under the street.
“That’s our best hypothesis,” Hawkins said.
The blockage in the storm drain was discovered Friday when workers threaded a camera into the drain. Authorities don’t know when the manhole was installed, but the dirt appears to have been washed out over a period of several years, Hawkins said.