Time is running out for viaduct visionaries

Seattle is still in the imagination time about the Alaskan Way Viaduct, though we are getting close to the end of it. Gov. Christine Gregoire, fearing the legal liability of keeping the viaduct, says flatly, "I want it replaced."

Last week, at a meeting of the Seattle Marine Business Coalition in Ballard, two retired structural engineers of long experience, Victor Gray and Jack Christensen, presented a plan to not replace it, but to brace it. They say the viaduct is damaged where it curves but is not in too bad a shape overall, and that dampers and inverted V-shapes of steel could restore it for the next 30 to 50 years for about 10 percent of the cost of a rebuild.

State bridge engineer Jugesh Kapur of the Washington Department of Transportation (DOT) disagreed. He said the viaduct is weak in the joints and foundations — weaker than the retired engineers think — and that fixing it would not be worth it.

The Nisqually quake is said to be a one-in-220-year event. The retired engineers say their proposal could meet the 500-year earthquake standard, meaning that in the worst quake likely in any 500-year period, no one would die. Kapur said the state now uses a 2,500-year standard for big projects like the viaduct and the Tacoma Narrows Bridge.

Gray said the 2,500-year standard is excessive for a retrofit designed to last 30 to 50 years. Kapur said later, "We are not going to lower the bar to make the viaduct look good."

The Ballard business people, many of them on the Ship Canal or in Interbay, had a more immediate concern: closures of Highway 99.

"We need it open," said Patrick McGarry, Northwest manager for Manson Construction. A long shutdown, said Doug Dixon, general manager of the Pacific Fisherman Shipyard, "will put the Ballard industrial base out of business."

Either a new viaduct or a tunnel will shut down the corridor for 18 to 42 months and partly close it for five to six years. "Partly close" means no entry or exit at the viaduct's northern end, which is where Ballard uses it, and perhaps one-way traffic on Highway 99 for long periods, said Bob Chandler, project manager for the city of Seattle.

"We're still working on it," he said.

The Ballard meeting did not consider replacing the viaduct with a road. There are several versions of this. The People's Waterfront Coalition, which does not like highways, proposes a four-lane city street with stoplights. The DOT never considered this, but it did look at a proposal for a six-lane street with 12 stoplights. It estimated that rush-hour speeds would fall to 8 miles an hour.

One might imagine a six-lane avenue with no stoplights and no turns — a sort of Aurora on the waterfront. It would not be pretty, and there would be noise. But it would work. The traffic would move and the views from buildings would be tremendous.

Engineer Dave Petrie suggests this with a lid on it. The lid would cut the noise, but it would create a 19-foot wall about a mile long. And, like a tunnel, a lidded road would not be available for trucks carrying hazardous cargo. Petrie was at Ballard working the crowd for his proposal, but I have not found anyone as excited about it as he is.

For all such viaduct visions it is probably too late. Says DOT project manager Ron Paananen, "There are only two projects we're looking at now": viaduct and tunnel.

In November, the people of Seattle will cast advisory ballots for a new, 25-foot-wider viaduct, for which the money is in hand, or a tunnel, which costs $1.2 billion to $1.6 billion extra. Says the governor to Seattle, "If you want a tunnel, you've got to pay for it."

The money is in hand for a new viaduct, at least. I think that means the retrofit is out.

Bruce Ramsey's column appears regularly on editorial pages of The Times. His e-mail address is bramsey@seattletimes.com