Options for replacing Viaduct down to two

The Alaskan Way Viaduct will either be rebuilt or replaced with a tunnel, the Washington State Department of Transportation said yesterday, essentially narrowing its options for replacing the earthquake-damaged structure from five to two.

"These seem the most logical and viable alternatives on the table," said Maureen Sullivan, urban-project director for the DOT.

The urgency to replace the bridge, which carries 110,000 cars a day, came after the February 2001 Nisqually quake, which caused major damage to the viaduct. The road was built in 1953 to carry 64,000 cars a day.

In a presentation yesterday to legislators, Seattle City Council members, Mayor Greg Nickels and others, Sullivan said that rebuilding the viaduct or replacing it with a tunnel are the most likely options for replacing the bridge and seem to be the most popular among those who responded to an environmental-impact statement produced for the project.

She said the three other alternatives — a new bridge, a bypass tunnel and the cheapest option, a widened Alaskan Way arterial — are still on the table but are unlikely choices now.

"No one is supporting the surface and the bypass, and the new bridge is pretty wide and massive," Sullivan said.

Under one plan, supported by arts organizations and the Greater Seattle Chamber of Commerce, the viaduct would be replaced with a tunnel along the central waterfront carrying three lanes in each direction. An aerial structure would connect the tunnel from the waterfront to the Battery Street Tunnel and, in the south, the viaduct would be replaced with an at-grade roadway.

This is the most expensive option, with cost estimates of $3.6 billion to $4.1 billion. It would take from seven to nine years to build.

Arts groups, such as Allied Arts, like the tunnel idea because they say it would open up the waterfront and rid it of the viaduct obstruction.

The rebuild alternative, backed by a group of Magnolia residents, would replace the viaduct, in its existing location, including ramps into downtown at Seneca and Columbia streets. In the south the viaduct would be replaced with an at-grade roadway and interchange near the sports stadiums. It is estimated to cost $3.2 to $3.5 billion and would take six to eight years to build.

Magnolia residents like the rebuild option because they say it would provide better access to their neighborhood.

Tim Ceis, Seattle's deputy mayor, characterized the tunnel and rebuild as "emerging as front-runners" and said, "obviously, the city's needs are better met with the tunnel in terms of impact on the waterfront, noise pollution and the visual barrier along the waterfront. The downside is it's more expensive."

Seattle City Councilman Richard Conlin, chairman of the council's transportation committee, said he doesn't agree with narrowing the options and thinks it's premature. "I want to look more at mixes and matches," he said.

But Conlin did score one victory with the transportation department. Conlin is an advocate of studying a sixth alternative — tearing down the viaduct and not replacing it. The state now says it is finishing an analysis of that idea, although Sullivan said that's an unlikely scenario given the volume of traffic on the viaduct.

She said the state plans to pick its preferred viaduct alternative by the end of October and said it's crucial to choose a plan soon so the state can look for financing. Sullivan said it will be a joint decision among the state, city and federal governments.

She said the state is envisioning that it would contribute $2 billion to the project and the rest would come from other sources, such as the Army Corps of Engineers, possible federal funds dedicated to mega-projects, the city, the Port of Seattle and a possible voter-approved regional-transportation package. She said there probably would not be tolls on the viaduct because of all its exits.

There's still no money to replace the viaduct, other than $177 million as part of the nickel-a-gallon gas-tax increase approved by the Legislature.

As part of the viaduct-planning process, the state has always said it intended to keep the viaduct open during construction. Now it has agreed to study what would happen if it closes the roadway. A group of Seattle waterfront-business owners has asked the state to study whether to close the viaduct during construction because it could shorten construction time and save money.

David Hancock, an attorney with Graham & Dunn on Pier 70, said "there could be immediate gridlock and foul up Interstate 5, but we just want an assessment, not a knee-jerk assumption that this will gridlock everything."

"Would it save time and dollars?" asked Sullivan in listing the questions to be answered in the report. "Is it worth the additional grief for traffic and how far spread out would the grief be?"

That report is due to be completed this week.

Meanwhile, the state will close the viaduct later this month to see if it is still moving. Last February a study found that it was moving and was only 2 inches away from potentially expensive repairs. After the Nisqually earthquake damaged the viaduct, the DOT established semiannual inspections of the bridge to see if there was movement of the structure.

Susan Gilmore: 206-464-2054