The sudden closure of the West Seattle Bridge requires instant traffic detours

The emergency closure Monday night of the high-level West Seattle Bridge has created a dilemma not only for travelers, but also city leaders who’ve had no time to plan other traffic routes.

First comes the immediate need for commuters and deliveries to reach West Seattle this week. Mayor Jenny Durkan said the two-lane swing bridge below is reserved for emergency vehicles, transit and freight only, though for much of the day Tuesday, some general traffic passed through. The walk-bike lane remains open to all.

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Then hopefully later this year, the coronavirus epidemic will lift and people will return to work and play — but the landmark, arched span that carries 107,000 daily vehicles will still be off-limits as cracks in support girders are repaired. It could take months to reinforce the bridge, possibly using giant sheets of carbon wrap.

“We’re definitely talking about months, it’s not going to be weeks. It’s safe to say that whatever we do, it’s probably going to last longer than COVID-19,” said Ryan Avery, senior research engineer at the Washington State Transportation Center, at the University of Washington, who currently telecommutes at his West Seattle home.

Seattle officials announced Monday the bridge will be closed, possibly for months, until the city repairs cracks that render the span structurally unsound.

To drive to and from the peninsula, drivers now must take circuitous paths such as down Highland Park Way Southwest to the First Avenue South Bridge and then either north on East Marginal Way, or east on South Michigan Street to I-5. Some others are equally mazelike, such as South Roxbury Street to Myers Way South, descending to Highways 599 and 99 northbound interchanges.

Some commuters will hasten through residential zones and minor arterials where the city has tried for years to calm traffic. Many alternate paths, through the High Point and Roxbury areas, pass schools and playgrounds.

City Councilmember Lisa Herbold, a Highland Park-area resident, is already proposing changes and forwarding ideas from constituents.

Topping the list would be the hilltop intersection where industrial Highland Park Way meets neighborhood Southwest Holden Street, site of frequent T-bone crashes. Immediate safety changes are needed, both Herbold and Avery say — compounded by the fact a planned roundabout there was never built.

A traffic stoplight should be installed there, Herbold said Tuesday.

Residents are asking for a turn light next to the Delridge Way Home Depot, and speed cameras on Sylvan Way Southwest near Delridge where drivers will travel to Highland Park.

Herbold also mentioned an exemption for health-care workers to drive on the lower bridge.

Another potential problem is South Park, a low-income neighborhood that has room for 40,000 vehicles on its new four-lane bridge. But to get there, many drivers would zip past homes and children on narrow arterials.

“That’s a nonstarter, in terms of community impact,” Avery said.

Herbold and Councilmember Alex Pedersen, who chairs the Transportation and Utilities Committee, say they were notified just Monday afternoon of what appears to be a rapid decision by SDOT, following a bridge inspection a few days ago. Also, the span didn’t appear on the SDOT watch list of urgent projects that council members closely track, Herbold said.

With heavier bus traffic across the bridge in recent years, Herbold has sought repaving on the bridge, but recalls that “no one has said to me, ‘by the way while you’re worried about pavement conditions, you should be aware we’re having this problem with the bridge too.’ ”

So what about after the virus passes?

The First Avenue South Bridge, which already carries 100,000 daily trips in normal traffic, probably doesn’t have a lot of extra capacity, Avery said. “I would expect your trip time to double in peak times, or triple, and there will be a high degree of unreliability.”

He does praise King County Executive Dow Constantine’s effort to create more Metro bus connections and more water taxi trips. The water taxi will help, but will absorb only a fraction of trips, Avery said.

As long as the low-bridge traffic is restricted, transit will move slightly faster than usual, he predicted. “When things return to normal I think people need to ride the bus, if they want to go downtown,” he said.

With the bridge out, Avery thinks that many people will need to keep telecommuting even when the coronavirus outbreak ebbs, or at least change work hours.

Shooing people away from crowded highways could be easier this time than during past road closures, he hopes. People are getting lots of practice now. “I was joking with friends, there isn’t a better time for this to start,” Avery said. “But it will outlast the pandemic.”

Staff reporter Heidi Groover contributed to this story.