Report: Oregon bridges continue to age, deteriorate

The good news: ODOT is making progress in seismic reinforcement of state bridges, and work is scheduled to start later this year on the George Abernethy Bridge, built in 1970, which carries Interstate 205 across the Willamette River between West Linn and Oregon City. The work will eventually cover nine bridges in a seven-mile stretch of I-205 between Stafford Road and Highway 213 in Oregon City.

Time is working against state bridges, more than half of which were built before 1970, during the interstate highway era. A bridge has a normal lifespan of 50 years, although its usefulness can be extended.

Under a 2017 state transportation financing law, $12 million is generated annually for bridge repairs, up from $10 million in 2018. The recent federal infrastructure financing law, which President Joe Biden signed on Nov. 15, will yield a total of $268 million more earmarked for bridge repairs over the next five or six years.

Still, at the current rate of three bridges annually, it will take 900 years to replace the 2,750 bridges in the state system. ODOT estimates its bridge maintenance backlog at $5 billion. Robert Van Brocklin of Portland, chairman of the Oregon Transportation Commission, said the new federal funding helps with bridges and other transportation needs — but it is not enough.

“We can make progress on many of our goals, but we cannot solve the vast majority of our funding problems with the money from this legislation,” he said in a statement after a commission meeting Jan. 20. “We also need to pursue other revenue sources to produce sustainable transportation funding to invest in a reliable, diverse transportation system.”

But the report says important bridges, such as the Columbia Slough Bridge that offers access to the industrial area on Marine Drive in Portland, are left out because they are not on state highways and not on priority routes. Built in 1933, the main span of that bridge has steel girders supported by a concrete foundation, but 11 other spans are timber.

Unlike pavement conditions on highways, there are few alternatives for poor conditions on bridges, other than load limits or long detours.