WASHINGTON — Drivers may have noticed that D.C’s 3rd Street Tunnel is getting longer.
The $1.3 billion Capitol Crossing project will eventually add four office buildings and one residential building right over I-395, and an elevated deck that will hold the first building is now finished.
With help from a recently added crane, construction work is starting on the building itself, at 200 Massachusetts Avenue in Northwest.
Capitol Crossing is the largest private development underway in the District, and will create 2.2 million square feet of space on a seven-acre site.
“It’s a fascinating engineering challenge and we’ve got three major structural engineering firms working on it, all of whom have a lot of experience with major infrastructure projects like this,” Bob Braunohler, regional vice president of developer Property Group Partners, told WTOP.
To support the buildings, huge concrete footings, eight feet in diameter, were sent 100 feet into the ground.
“Part of the reason we had to do that is because there’s no bedrock under this site. This used to be an old streambed. That’s why the caissons had to go so deep,” Braunohler said.
The completed deck covers the highway from Massachusetts Avenue to G Street between 2nd and 3rd streets, and the deck will eventually be extended two more blocks south to E Street.
Excavation work will start soon on land west of the highway.
“That’s where we’re going to build a parking garage that runs the whole length of the project, and serves all five buildings. So that’s going to start in about two weeks,” Braunohler said.
In coming months, drivers can expect overnight lane closings on I-395 and more work at street level.
Braunohler said they have a letter of intent with a major unnamed tenant interested in moving in to Capitol Crossing.
“It’s an exciting tenant … it should help establish this location as a destination,” he said.
The project will go beyond LEED Platinum standards by recycling water captured on-site, using combined heat and power and installing “EcoChimneys” to clean the air.
Construction on the first building is expected to be finished in 2018, with the entire project on track for completion around 2021.
“When we’re finished here, we’re going to have 10,000 people either living or working in these three blocks,” Braunohler said.
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