‘Indefinite shutdown’: Stress cracks endanger West Seattle Bridge

VIDEO: West Seattle Bridge closes over safety concerns

SEATTLE — In a sudden, indefinite safety closure that many drivers found jolting, city SDOT engineers closed the West Seattle Bridge Monday night to repair cracks weakening the enormous support columns which hold the bridge up.

Estimates of the length of the closure vary, but the complexity of the issue suggests repairs could take months.

"There's concerns that the West Seattle high rise bridge cannot safely support vehicular traffic at this time," said Seattle Mayor Jenny Durkan.

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Durkan explained engineers have been watching and repairing stress cracks in the high-rise West Seattle Bridge for years, but an inspection last weekend showed the cracks becoming severe enough to deteriorate the strength of the support columns.

According to SDOT Director Sam Zimbabwe, the cracks were so severe, the bridge was not safe for typical pre-pandemic crisis traffic, which was about 100,000 vehicles per day.

"The extent and the type of cracking that we've seen have concerned our structural engineering experts to the point what we're removing live load traffic from the bridge in the best interest of public safety at this point," Zimbabwe said.

Cracks can clearly be seen in the sides of the upper high rise-rise bridge deck, but SDOT engineers say much of the danger is deteriorating the interior of the support columns, where water and air are said to be seeping in and weakening the structure.

Drivers navigating the maze of detour signs were frustrated at the thought of driving one of several longer routes to cross the Duwamish Waterway.

"It's going to be really hard travel to get across," said John Hampton. "I live all the way up in Bothell, and I work at the tire center here, so it's going to be stressful."

"In some ways I guess it's fortunate that traffic volumes are so low." Durkan said. "But we know that as we get through this COVID emergency, those traffics hopefully will be increasing and we have to have a plan in place."

According to SDOT, all vehicles will be prohibited from crossing the high-rise span of the bridge between I-5 and Fauntleroy Way SW.

Buses, freight and emergency vehicles will be moved to Spokane Street Bridge, which is also called the “low bridge.” Motorists should use the First Ave or South Park bridges.

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