May 17, 2018

Kiewit wins $94M job to demolish viaduct

Photo from WSDOT/Flickr [enlarge]

The southern mile of the viaduct was demolished in 2011-12 by Rhine Demolition. Skanska USA Civil was the general contractor.

Washington State Department of Transportation yesterday selected Kiewit Infrastructure West Co. to demolish the Alaskan Way Viaduct under a design-build contract valued at $93.7 million.

Kiewit submitted the apparent best value bid, which considers technical proposals as well as price. It beat three other shortlisted teams: Granite Construction, Flatiron West, and a joint venture of Myers & Sons Construction and Silverado Contractors.

“It will be challenging to tear down a major highway in the heart of a booming city, but we're looking forward to getting it done safely and as quickly as possible,” said Brian Nielsen, WSDOT's Alaskan Way Viaduct Replacement Program administrator, in a news release.

The work area covers 1.4 miles, from South Dearborn Street to Battery Street Tunnel.

Kiewit will remove most of the cast-in-place viaduct's 397 foundations and footings to five feet below grade. An on-ramp at Columbia Street and an off-ramp at Seneca Street will also be removed.

Earlier this year, Nielsen said parts of the viaduct near buildings may have to be cut into pieces and removed by crane. That would be slower and more expensive than traditional methods, he said.

Kiewit's contract includes two other large components: decommissioning the Battery Street Tunnel; and regrading Aurora Avenue North between Harrison Street and Denny Way, and making road connections at John and Thomas streets.

Combining these three projects under a single design-build contract is expected to shave a year off the construction time.

The schedule for the work won't be determined until after the contract is final and Kiewit receives approval to begin design work. WSDOT estimates demolition will be finished in fall 2019.

A Kiewit official didn't respond to a request for comment.

The replacement tunnel is expected to open this fall. At that time, the temporary Alaskan Way surface street will move west from under the viaduct, with two lanes in each direction along the waterfront.

Crews also will remove the Marion Street pedestrian bridge that crosses below the decks of the viaduct to connect with the ferry terminal. A temporary replacement bridge is included in the contract, but not a permanent bridge.

WSDOT said Kiewit could start limited demolition work late this year. Initial demolition will remove part of the viaduct to make room for a new road near the stadiums.

Demolition will be performed in sections to minimize the disruption.

WSDOT will close the viaduct for three to four weeks before the replacement tunnel opens along the waterfront. This closure is needed to realign state Route 99, finish access ramps and connect the highway and tunnel.

The southern mile of the viaduct was demolished in 2011-12 by Rhine Demolition as part of a larger project to replace that section with a new side-by-side roadway. Skanska USA Civil was the general contractor.