CONUNDRUM ON THE COLUMBIA
Project exemplifies Interstate work

Few projects better illustrate the challenge of carrying the Interstate Highway System into its second half-century than the Interstate 5 Columbia River Crossing.

In the nearly 90 years since the first of the twin, 3,528-ft., steel-through-truss, vertical-lift-span structures was built, the corridor connecting Portland and Vancouver, Wash., has become the nexus of a rapidly expanding metropolitan area of two million residents. As a critical link in North America's primary West Coast commercial route, the bridge's daily load of 125,000 automobiles, buses and heavy trucks is expected to increase by 40 percent in the next 20 years.

But there's much more facing the Oregon and Washington transportation departments than simply insufficient corridor capacity.

In an area that has long embraced alternative transportation modes, the crossing offers only a narrow path for pedestrian and cyclists, and no special provisions for buses or other transit systems. Peak traffic periods often overlap with the Coast Guard-designated windows for raising the 279-ft.-long lift span for the Columbia's maritime traffic, stalling traffic for miles in both directions.

Downstream-bound tugboat-barge combinations that can slip through the normal 72-ft. clearance beneath the bridge's fixed center spans have less than a mile to reposition themselves for a rail bridge's narrow north-side opening.

The complications continue on both sides of the Columbia, in the form of congested interchanges and bottlenecks; limited right-of-way for construction; sensitive environmental areas; nearby historic sites; two sets of state and local level permitting and approval processes; and any number of stakeholder groups with diverse and often-conflicting priorities.

Small wonder that project spokesperson Rob DeGraff characterizes the Columbia River Crossing as "a four-dimensional jigsaw puzzle."?

Nevertheless, it's a challenge that the two DOTs are determined to solve. Since 2000, the agencies have been collaborating with local officials to map a holistic approach for relieving I-5's congestion woes within a 5-mi. "bridge influence area" from SR 500 in Vancouver to Columbia Boulevard in Portland.

After a series of studies and option assessments, a 39-member advisory task force of business, neighborhood and community leaders began evaluating the lengthy list of proposed highway and transit improvement options for resolving the corridor's safety and capacity needs.

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The first major screening took place in March, when the task force eliminated several proposals, including construction of a tunnel, upgrading the upstream Interstate 205 bridge-another structure nearing design capacity-and heavy-rail options such as monorail and maglev systems.

The task force also shelved the long-standing controversial idea of adding a third crossing downstream of I-5, arguing that it offered only minimal benefits to the corridor's congestion problems. A various designs for supplemental or replacement bridges. The remaining six transit options include light rail, buses and streetcars. Plans call for narrowing the options into a locally preferred alternative that ODOT and WSDOT can submit for federal approval in early 2008. Preliminary design and construction steps such as right-of-way acquisition could begin soon afterward.

Although a great deal of debate and decision-making lies ahead, DeGraff said many design and construction issues are already evident.

For example, "We have to provide enough clearance for large vessels, but we also have to consider the proximity of Pierson Air Park, which is home to many historic aircraft with limited climbing ability," DeGraff added. "Together, those constraints significantly restrict the height and profile of any new structure."

DeGraff said that constructability and maintenance of traffic will loom large in the planning process, particularly since "we're talking about a 5-mi. freeway corridor with eight interchanges that need to be reconstructed."

Construction crews will find elbowroom at a premium, given the dense commercial development adjacent to I-5 in the economically revived Vancouver and the presence of wetlands and Delta Park on the Oregon side.

"Any potential solution will be threading a needle," DeGraff said.

The states of Oregon and Washington can also count on a hefty price tag for whatever Columbia River Crossing strategy emerges. While the project sponsors have not officially speculated on cost estimates, a 2002 study by the Portland/Vancouver I-5 Transportation and Trade Partnership put the cost of freeway, bridge and transit improvements in the bridge influence area at more than $2.2 billion.

For now, the most important hurdle facing the Columbia River Crossing is achieving a consensus solution. DeGraff said that while Oregon and Washington transportation officials have the final say as to how the Columbia River Crossing will proceed, their decision will be shaped by representatives of two communities that typically have different priorities and approaches to transportation, land use and planning.

"Everyone has to get on the same page," he added.