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Can Seattle Stop Its Highway Tunnel Boondoggle Before It’s Too Late?

It's been one year since the world's largest tunnel boring machine, "Bertha," got stuck 120 feet beneath Seattle. Before it broke down, the colossal machine had excavated just 1,000 feet of the two-mile tube that's supposed to house a new, $3.1 billion underground highway to replace an aging elevated road called the Alaskan Way Viaduct.
Is it too late for Bertha? Photo: WsDOT
Seattle and the state of Washington have a window of opportunity to stop throwing good money after bad. Photo: WsDOT

It’s been one year since the world’s largest tunnel boring machine, “Bertha,” got stuck 120 feet beneath Seattle. Before it broke down, the colossal machine had excavated just 1,000 feet of the two-mile tube that’s supposed to house a new, $3.1 billion underground highway to replace an aging elevated road called the Alaskan Way Viaduct.

Bertha hasn’t budged an inch in the 12 months since. Meanwhile, the bad news keeps on piling up.

Right now, the state’s contractor is busy building a second tunnel down to the machine, so that parts can be removed, repaired, and replaced. In order to keep the second tunnel dry, construction crews have been draining the water table. This work has dangerously destabilized the very elevated highway the tunnel is supposed to replace, and one of the city’s historic neighborhoods — Pioneer Square — is actually sinking as well.

As David Roberts detailed in a recent Grist story, the project could impose billions of dollars in cost overruns on the public. Nobody is certain the machine can be fixed, or if it does get fixed, whether the same problem won’t occur again, farther down its path. In December, the deep-bore tunnel ran away with the voting for Streetsblog’s “Highway Boondoggle of the Year” award.

If there’s anything positive to emerge from the current mess, it’s that local advocates like Cary Moon, who warned against building the tunnel in the first place, are commanding attention again. Moon recently took to the pages of the local alt-weekly, the Stranger, to argue that in light of the tunnel project’s spectacular, slow-motion meltdown, the city should explore other options.

We reached out to her to learn more.

This is a pretty big disaster, it sounds like.

This project identified a lot of risks at the beginning of the process, but the political commitment to it was already high enough at that point that no one really paid that much attention, except for several of us.

They treated us like we were gadflies instead of pointing out honestly and clearly what was probably going to happen. It’s frustrating because all this was known then but no one was listening.

Photo of Angie Schmitt
Angie is a Cleveland-based writer with a background in planning and newspaper reporting. She has been writing about cities for Streetsblog for six years.

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