Caltrans Begins Ambitious Project To Replace US Highway 101 Bridge Deck At Alemany Circle In San Francisco
SAN FRANCISCO (KPIX 5) -- Caltrans crews on Friday took advantage of the reduced traffic during the lockdown, starting work on a major project that's closing U.S. Highway 101 near the Interstate 280 split in San Francisco.
The project to replace the US 101 Bridge Deck at Alemany Circle will provide an upgrade for one of the Bay Area's most heavily traveled corridors that connects the Peninsula to downtown San Francisco. Over 240,000 vehicles travel through the corridor on a daily basis, though the volume of traffic is down considerably due to the coronavirus stay-at-home order.
Construction commenced Friday with a temporary detour of northbound 101 traffic onto highway 280. One lane of southbound 101 is also closed near the construction site.
Caltrans originally planned to do the work in July 2020, but pushed the start time up to this week given the reduced traffic from the Bay Area sheltering in place. The plan is to complete the project in a shorter timeframe before the state's stay-at-home order is lifted further reducing the impact to local and regional traffic.
From the air, the point where Highway 101 northbound is closed at the 280 split is plainly visible, as are the Caltrans crews working the project. If there's an upside to the stay at home order, it's that commuters are avoiding the six-mile long backups this project that would have caused in July had it not been pushed up.
"With people staying at home right now, traffic counts have come down between 40 and 60 percent, which gave us a tremendous opportunity to do this and not impact people," said CalTrans spokesperson Bart Ney.
A crew of 100 people working around the clock will be demolishing 800 feet of bridge deck and replacing it in the space of less than two weeks.
To minimize noise, dust, and vibrations from the project, Caltrans will be sawing away sections of the bridge deck and removing them whole, rather than jackhammering to demolish the bridge deck.
"So what we're doing is we're saw cutting sections out of it, lifting them out of place and then pouring a new deck in place," Ney explained.
After the northbound deck is complete, southbound 101 traffic will be shifted onto the new northbound deck. The southbound deck will then be demolished and rebuilt.
To make the project happen, about three months of prep work got condensed into three weeks as contractors shored up their supply chain and figured out new rules for the job site, including wearing face covering and mandatory temperature checks.
"Wearing masks, wearing bandanas, wearing gloves; when we can be six feet apart, people are trying to keep their distance," Ney said.
The closure and construction is scheduled to last until May 3rd, but could be done even sooner.
"The contractor believes we can take it down to 10 days or less," said Ney.
Caltrans has additional information about the project available on its website. There are also multiple live web cameras showing the demolition and construction as it happens.
