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New video shows ‘rapid replacement’ option for West Seattle Bridge

SEATTLE — The design firm hired to plan a replacement of the West Seattle Bridge has a new video showing how the bridge could be dismantled and replaced quickly with a new superstructure.

Ted Zoli of HNTB told a task force on Wednesday that a bridge built with the method he suggests, which involves barging in premade steel trusses, means the bridge could open to traffic as soon as the first quarter of 2023.

“We feel that’s feasible given the fast-track start,” Zoli said.

City officials stress that Mayor Jenny Durkan has not reached a decision on whether to go with the so-called “rapid replacement” option, which came up late in a recent cost-benefit analysis of several other plans. Nevertheless, the possibility of opening a bridge three years earlier than that analysis suggested for a similar replacement has clearly captured the imagination of city officials and task force members.

“This is an intriguing option and I’m very happy it’s come forward. It needs to be vetted,” said former mayor Greg Nickels, who co-chairs the task force.

The rapid-replacement plan is based on the Lake Champlain Bridge between Vermont and New York, which was replaced in 18 months.

The Seattle Department of Transportation only has a rough cost estimate at this point, which suggests a rapid replacement would be about $400 million in upfront costs, with a lifetime cost, including maintenance, of about $1 billion.

Zoli said the bridge he suggests building could last 100 years.

SDOT officials expect Durkan will make a decision about various repair and replacement options by the end of the year.

As to where the money might come from, SDOT officials said they are putting the “finishing touches” on a financial plan, and that bridge money would come from a variety of sources.

Officials said a consultant is reviewing whether tolls might be feasible to help pay for a new bridge.

See video below showing how the West Seattle Bridge could be dismantled and replaced quickly.