Maybe we should try McGinn's idea to shut the viaduct now

Our mayor's a recovering lawyer, so it's no surprise he likes to talk. But from his lips may have unwittingly flapped a way to end Seattle's 10-year talkathon over the Alaskan Way Viaduct.

Shut it. No, not Mike McGinn's mouth (although that might do the trick, too). Shut the viaduct.

McGinn suggested this Monday in an off-the-cuff response about the earthquake in Japan. Maybe we should close the viaduct to traffic, soon, instead of in another five years as planned.

"When you see what's going on in Japan, and you see the potential loss of life and damage that could be done, I really think it's appropriate to evaluate whether it's right to say we're gonna leave it up until we get this other solution in place," McGinn said on KUOW.

Look out. It was as if the mayor had started jack-hammering the concrete columns himself.

He was called a reactionary, a bomb-thrower, an exploiter of fears. A fomenter of total transportation chaos.

"It's amazing to hear the mayor say that," said Seattle City Councilmember Tom Rasmussen. "The viaduct carries 110,000 vehicles a day. To shut the viaduct down, it would be total gridlock."

Would it really? Would it even be partial gridlock?

This is the unresolved crux of this entire infernal debate. Count me as skeptical, or at least curious. What would happen if we took the mayor up on his idea?

Gridlock is what they forecast when they shut most of I-5 a few years back. There could be 30-mile traffic jams, they said. It never happened.

Same thing when they shut the downtown bus tunnel for two years. Buses would jam the streets, they said, triggering big tie-ups. Also didn't happen. In fact, Metro said buses moved through downtown more swiftly, on average, than before the closure.

These were not miracles. If you give drivers a heads-up before a road closure, and also make a series of adjustments to the system, the predicted crush of humanity often never materializes.

In the case of I-5, an astonishing 50,000 cars that normally use the freeway didn't appear. And didn't jam side routes either.

Now it's one thing to do this for three weeks, as with the I-5 shutdown. Or with a transit tunnel. Living without one of our main north-south highways might finally bring the gridlock-apocalypse they're always predicting.

What has hung up the viaduct project for a decade is that nobody knows. Some experts and studies say we can live without a waterfront highway. Others say as assertively that we can't.

I am so weary of this issue that I admit I was hoping our so-called leaders would ram through some plan and be done with it. I agree with Councilmember Nick Licata, who theorizes the problem all along has been that there isn't majority voter support for any idea on the waterfront (there have been more than 70 discussed to date).

What's the point of voting — again — if we seem to know only what we don't want?

So instead, let's shake it up. It may solve both a safety problem and a political one. Give six months' warning, and use that time to do a slew of little fixes to transit, Spokane Street and the rest of the street grid. Then close the viaduct and see what happens.

I bet we'd know within a few weeks whether we can live without it. Me, I'm most worried whether freight, the Port and industry can get around. We'd find out. Do this shutdown well before any vote and at least the public would be in a better position to judge.

This exact experiment was proposed five years ago by a group of University of Washington faculty. Nobody listened.

I called one of them, earth-sciences professor Dave Montgomery, to see if he thought anyone might listen now. What with quakes and the mayor so much in the news.

"We wrote that five years after the Nisqually quake," he mused. "Now another five years have gone by. It's really starting to get into geologic time."

Yep. For now it's still our move. Eventually it's going to be Earth's.

Danny Westneat's column appears Wednesday and Sunday. Reach him at 206-464-2086 or dwestneat@seattletimes.com.