West Seattle Bridge Repairs Could Begin As Early As October

SEATTLE — The next stage of the West Seattle Bridge repairs could begin as early as October.

According to the latest update from the Seattle Department of Transportation (SDOT), this week the city reached an important internal milestone, completing and submitting an intermediate outline of the next phase of repairs.

SDOT says that means it remains on track to reopen the bridge to commuters by mid-2022.

Now that the intermediate design milestone has been set, the department is working on the final design, which will be submitted in September. After that, the last phase of construction can begin.

SDOT has already contracted Kraemer North America to handle the final bout of work. Previously, Kraemer worked with SDOT on the Northgate Pedestrian and Bike Bridge and had been involved in the emergency stabilization of the West Seattle Bridge.

The West Seattle Bridge was first closed in March 2020, when SDOT engineers discovered a series of cracks and structural concerns. Before the closure, the bridge carried upwards of 100,000 commuters per day.

The city debated replacing the bridge outright, until November 2020 when Mayor Jenny Durkan ultimately elected to repair the bridge instead. The repair process is cheaper and quicker than a replacement, which would have cost up to $522 million, but is only temporary, and the bridge will need to be fully replaced within 15 to 40 years.

Since the decision was made to repair the bridge, crews working with SDOT, including Kraemer, have installed more than 10 miles of steel cable inside the structure, wrapped several portions of the bridge in carbon fiber for emergency reinforcement, and fixed a deformed bearing in one of the support piers.

When the final phase of rebuilding begins, construction will largely be focused on filling cracks, reinforcing the main span, adding more carbon fiber wraps, and strengthening two segments of the bridge's side span.

"While our teams are confident that these repair methods will be successful in bringing the bridge back into service on schedule, that doesn’t mean the process is simple," writes SDOT's Katie Olson. "It requires careful and complex planning: barging temporary work platforms into place over the working Duwamish Waterway, mobilizing skilled construction crews, and procuring steel cable and carbon-fiber wrap to be installed along multiple spans of the 1,300-foot long and 140-foot tall bridge."

Crews will also be installing a long-term bridge monitoring system, which SDOT says will continue to check the bridge's structural integrity even after it is reopened to traffic in 2022 to ensure no further problems arise.

SDOT is inviting anyone with further questions about the bridge repair process to attend a virtual public meeting this coming Wednesday.