Seattle Mayor Greg Nickels says the city "will not support" any option other than a multi-billion dollar tunnel to replace the aging Alaskan Way viaduct, regardless of what the governor decides. The mayor's alternative? Send all those viaduct drivers onto city streets.

Seattle.gov

An artist's rendering of what the Seattle waterfront would look like without the viaduct.

Governor Christine Gregoire could decide as soon as next week what she wants to do with Seattle’s aging viaduct. Her options: build a new viaduct, fix the existing structure or invest in a $4 billion tunnel.

Nickels wants the tunnel, and now it appears it’s his way or the highway.

“Should the governor choose an elevated structure we've indicated that we don't support an elevated structure,” Nickels said. “That a distant second choice would be to go to a surface option.”

A surface street option would mean diverting 103,000 trips per day through the waterfront and downtown, in a city already choked with traffic.

If Gregoire opts for anything other than the mayor's tunnel, he could try to block the plan by not approving permits, withholding funds or through legal action.

Nickels would only: “We will cross that bridge if we come to it.”

But if the mayor blocks any non-tunnel proposal, countless drivers could be forced to cross the crumbling and earthquake-prone viaduct for a lot longer that originally expected.

Right now it appears to be a risk the mayor is willing to take:

“It's not our first option, but the prospect of another 60 or 70 years of an even wider, more intrusive elevated highway along our waterfront is unacceptable,” he said.

Gregoire's office will only say the mayor's comments will not affect how she makes her decision.  When asked what the state would do if Seattle refuses to go along with anything other than a tunnel, a spokesperson said: "We can't comment on hypothetical."

A Department of Transportation study found that diverting viaduct traffic onto surface streets could increase congestion downtown from four hours a day to 13 hours a day.