In what is being described as tedious and labor-intensive work, DC Water contractors are removing layers of hard rock at the bottom of a manhole they are trying to excavate to 42 feet. They hit the rock at 30 feet and as of August 22nd, were halfway through.
The manhole in question is in the closed section of Albemarle Street east of Connecticut Avenue. Its excavation is part of the final stage of DC Water’s Soapstone sewer rehabilitation project. And that layer of rock is one of two reasons the agency is giving for the latest project delays.
DC Water had a three-month timeline for this phase when it closed the street last September, but the manhole held many surprises, including a large storm drain that no one knew was there, and had a cascading effect on the planning.
Another surprise discovery is still holding up the project: a ten-inch sewer pipe that wasn’t on any infrastructure maps, old or new. It’s believed to originate at Avalon the Albemarle (4501 Connecticut Avenue).
“We have found couple of illegal connections to our system, we suspect this may be another one,” DC Water’s Peter Tinubu wrote in an August 22 email to Forest Hills Connection.
Tinubu, the head of the project, says the sewer pipe likely dates back to the construction of the building [in the late 1950s]. DC Water needs to know where the pipe enters the building so it can control the flow of sewage for the last of its sewer relining work in the Soapstone Valley. And, “Avalon has been trying without success to find the as-built drawing.”
DC Water has done its own digging, with Avalon’s blessing, in a grassy area near the parking entrance, and has also had little success.
It’s that sewer connection – and not the rocky layer – that Tinubu says presents the greatest challenge to meeting DC Water’s projected September 11th project completion date, set in late May. Now, he says, mid-to-late October is more likely.
The final segment to be relined is a 325-foot pipe that flows from Albemarle Street into the park. Once that’s done, DC Water can begin to reassemble the manhole and the street.