County home to 21 deficient bridges

Four maintained by state, 17 by county

By LAUREN L. DILLARD

Of The News-Register

Twenty-one Yamhill Valley bridges have been classified as structurally deficient - the same rating carried by the Interstate 35W bridge that collapsed to spectacular and devastating effect into the Mississippi River in Minneapolis.

Four of the local bridges are maintained by the state and 17 by Yamhill County. The largest and most important of the bunch is the Three Mile Lane bridge spanning the Yamhill River in McMinnville.

None are thought to be in imminent danger, but then neither was the Minneapolis bridge. All undergo regular inspections, but then so did the Minneapolis bridge.

The county is responsible for 133 bridges in all. It has them inspected every two years by Burgess & Niple out of Columbus, Ohio.

"It's kind of a moving target," said Bill Gille, the county's director of public works. "We feel like we are on top of it, but we are always checking things."

In the past few years, 10 local bridges have either been replaced or rebuilt to meet current standards. But many more need attention.

In addition to the bridges classified as structurally deficient, the county has a number of bridges classified as functionally obsolete. That is to say they are not capable of meeting current demands.

Seven of these are currently on widening, upgrading or replacement schedules. None of them are thought to suffer from structural problems.

Gille said the county has bridges dated back to the 1920s, and they were built to the standards of the time. Over the intervening years, trucks have grown exponentially in size and weight, and that poses the principal problem.

"Frankly, cars don't break bridges," Gille said. "It's trucks."

Modern trucks are capable of hauling some very heavy loads, and he said, "Some of those bridges have not reacted well to that particular scenario."

According to the Oregon Department of Transportation, there is one absolute truth when it comes to bridges: "All things deteriorate." ODOT's Bridge Inspection Coding Guide goes on to note, "Bridges represent the highest unit investment of all elements of the highway system and deficiencies in that structure represents a reduction in the original investment."

Like Minnesota, Oregon is facing an enormous amount of deferred bridge maintenance, renovation and replacement. But unlike Minnesota, it has been moving to address that.

Under its OTIA III program, it is in the process of renovating or replacing more than 300 bridges around the state. There are no OTIA III projects in Yamhill County, but there are in all of its surrounding counties, according to Kelda Rericha of Oregon Bridge Delivery Partners.

The next Yamhill County structure up for replacement by the state is the Ash Swale Bridge, spanning Salt Creek near Amity. The project is on ODOT's action list for 2011, according to Spokesperson Adam Torgerson.

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