SEATTLE -- Authorities do not expect traffic to return to the West Seattle Bridge high-rise this year or even in 2021. They aren't yet sure if repairs are even possible.
Cracking has continued -- at a lower rate -- since the city closed the upper portion of the West Seattle Bridge to traffic three weeks ago, officials said Wednesday.
"We do not yet know if repair of the bridge is feasible technically or financially," transportation officials wrote in a blog post. "If repair is feasible, it’s likely this would only restore up to an additional decade of life to the bridge. In either case, we will need to replace the West Seattle High Rise-Bridge much sooner than promised when it opened in 1984. Further, should repair prove feasible, under a “best case” scenario we do not anticipate traffic returning to the bridge in 2020 or 2021."
According to the Seattle Department of Transportation, initial repairs and stabilization could cost $33 million. But that is early math and the price will depend on what workers learn about the bridge as they go.
But when it comes time for decisions, SDOT will have the help of a technical advisory panel consisting of bridge, construction, marine, and geotechnical experts from across the country to help review their work and explore every possibility.
On a typical weekday, more than 100,000 vehicles travel on the bridge, which has been closed since late March.
An inspection report from August 2013 showed that a part of the bridge, which is noted as Segment 11, which approaches midspan, was already showing "numerous cracks."
The cracks, however, were not significant enough to close bridge traffic.
Annual inspections of the bridge continued from 2014-2019 and showed low-level crack growth, according to SDOT reports.
A consultant group issued another report in January 2019.
"The cracks do pose a threat to the long-term performance as they allow for the ingress of moisture, chlorides and oxygen which can accelerate corrosion of reinforcing steel," the report said.
Inspectors noticed the crack growth from October-December of last year.
But it was another inspection in February of this year that showed the cracks were becoming more concerning. Inspectors recommended reducing traffic load on the bridge from two lanes in each direction. They also said work should begin this year to fix the bridge.
By mid-March, the cracks were no longer "static," but instead "dynamic," meaning the infrastructure is very concerning for everyday commuting.
Mayor Jenny Durkan announced the bridge closure on March 23.
You can read the inspection reports on SDOT's website.