Seattle Seeks Engineers to Design Possible West Seattle Bridge Replacement
Seattle has put out a request for statement of qualifications for engineers to help the city’s transportation department deliver a partial or full replacement of the West Seattle High-Rise Bridge, which was closed on March 23 to vehicle traffic because of excessive cracking.
City documents show that the contract, estimated at $50 million to $150 million, could last for approximately 10 years, but further details on the schedule will come later this year as officials work to determine if the current bridge can be fixed. “We continue to write flexibility into all our contracts and plans,” the city says in a statement. “Moving forward with this dual-track approach of repair and replacement is critical.”
Currently a design and construction team is under contract “working on the necessary steps to stabilize the structure and reduce the risk of failure,” the city says. Next steps, then, are to separately investigate a repair to the bridge for opening to traffic and to develop a replacement design. The city’s call for consultant services is to “obtain a comprehensive engineering team(s) to design a replacement of the West Seattle High-Rise Bridge.”
The Seattle Dept. of Transportation will first fix a bulging bearing on Pier 18 of the cracking West Seattle Bridge before it can move forward and see if the 36-year-old bridge is salvageable.
Once the bearing gets repaired, SDOT will “add additional support to make sure the bridge does not crack under its own weight,” says Sam Zimbabwe, SDOT director. “Then we can understand what we need to do to shore up the bridge and repair it and we don’t know yet if that is technically or financially feasible,” he says. “Each step will help us better understand what next step to take.”
Worsening cracks in the West Seattle Bridge, a 2,600-ft-long high-rise structure crossing the Duwamish River between West Seattle and Harbor Island, forced an emergency closure of the bridge on March 23. Since that time, SDOT has installed around-the-clock monitoring and announced a plan to hire Kraemer North America to repair Pier 18 bearings.
The second phase of work, constructing shoring to stabilize the bridge, will require “unique equipment and materials that require fabrication,” Zimbabwe says. He doesn’t expect that work would be able get underway until late in 2020, but much of that phase’s work will be determined by how phase one proceeds.
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If the bridge isn’t fixable, the city plans to “quickly pivot” to the replace option.
The city plans a pre-submittal meeting for Tuesday, June 9, and the request for SOQ must be received by the Seattle Dept. of Transportation by June 30.
