The late Sen. Everett Dirksen never said, “A billion here, a billion there, and pretty soon it adds up to real money.” But the quote has nevertheless become the go-to phrase when describing an escalation in spending or, in the design and construction industry, a project’s mounting costs.

It’s nice to know that the adage can work in reverse as well.

According to the Washington State Dept. of Transportation (WSDOT), the winning bid for replacing the southern end of the Alaskan Way Viaduct was $114.6 million—nearly $40 million under the state’s estimate of $152.6 million.

Should the bid from Skanksa USA Civil, Riverside, Cal., hold up, WSDOT will be getting a relative bargain to replace the southern mile of Seattle’s aging, seismically suspect downtown double-deck viaduct with a wider side-by-side roadway that meets current earthquake standards and provides better access to the sports stadiums and businesses of the city’s “SoDo” area.

It also bodes well for the next step in the Viaduct replacement program—constructing a 2-mile tunnel bored 200 feet below street level that will carry four lanes of traffic. That project, scheduled to begin in 2011, has a current estimated price tag of $1.96 billion.

Needless to say, state and local officials greeted the news of the SoDo section’s low price with grins usually reserved for the baseball heroics of Ichiro Suzuki.  But it’s important to remember that this fire sale on construction services is due in part to the still-depressed economy, and the fact that a lot of the region’s workers, equipment, and materials aren’t being used elsewhere.

And despite the best efforts of WSDOT and its consultants to identify and manage the risks associated with constructing the tunnel, there’s no guarantee that its estimated cost will hold up. Economic factors could cause costs to skyrocket over the tunnel's multi-year construction period, there may be some unwelcome "surprises" hidden in the fill bordering Elliott Bay, or an earthquake could provide the knock-out blow to the existing Viaduct, which is currently planned to remain in service until the tunnel is complete. 

On the other hand, the low bid seems to verify what construction industry groups have been saying all along—now is THE time to build infrastructure. All it takes is having the money to do it.  

That’s good news for the Viaduct tunnel project, which is now looking like a good deal after initially being criticized for its high cost compared with other options (an at-grade boulevard or retrofitting of the existing structure).

WSDOT has $2.4 billion in committed funding for the entire project (including the “SoDo” section) from the state’s gas tax and federal sources, plus a $300 million contribution from the Port of Seattle. The balance will be made up through tolls.

But if these trends hold, WSDOT may find itself getting change back from its proverbial construction dollar—a million here, and a million there….

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