Skip Top Navigation

US 12 Wishkah River Bridge load restriction lifted

Get Our Mobile App

  • Our Android and iPhone apps include statewide traffic cameras, travel alerts, mountain pass reports, ferry schedules and alerts, northbound Canadian border wait times and more.

Date:  Tuesday, June 19, 2012

Contact: Claudia Bingham Baker, WSDOT Communications, 360-357-3270 (Tumwater)

ABERDEEN – Local truckers will be pleased to learn that the Washington State Department of Transportation has lifted a load restriction on the US 12 Wishkah River Bridge in Aberdeen.

Effective immediately, WSDOT will grant qualifying truckers permits to haul overweight loads up to 22,000 pounds per axle. Previously, a load restriction had prohibited truckers hauling loads over 19,000 pounds per axle from using the bridge.

The change in the bridge’s load rating is the result of an in-depth analysis and physical testing of a key crossbeam in the bridge’s structure. WSDOT materials engineers drilled cores from the crossbeam’s concrete and tested its compressive strength.

“The results were amazing,” said Harvey Coffman, WSDOT bridge preservation engineer. “We found that the concrete in the crossbeam was almost twice as strong as we expected. In a bridge over 87 years old, that finding is quite impressive.”

WSDOT conducted the tests following concerns from local trucking companies that overweight restrictions on numerous bridges around Aberdeen were hindering commerce. After meeting with trucking representatives to identify key trucking routes, WSDOT subsequently looked more closely at load-restricted bridges on SR 107, SR 105, US 12 and US 101.

Bridge preservation engineers have identified fixes needed to lift the load restrictions on those bridges, which range from repairs by WSDOT crews to full bridge replacements. The needed repairs and bridge replacement projects will move forward as resources allow. In the case of the Wishkah Bridge, the test results showed the restriction could be lifted immediately.

With 3,200 bridges in the state inventory, bridge preservation engineers rely on construction and as-built documents to determine the grade of materials used during construction, and then use that data to calculate load ratings.

“People might wonder why we didn’t physically test the Wishkah Bridge before we placed the load restriction on it,” said Coffman. “I wish we had the resources to do that.
We do structural inspections every two years to look for bridge deterioration. Sometimes a special circumstance or request comes up, and we have the opportunity to take a closer look at a bridge. I’m glad in this case we have a satisfactory outcome.”

To learn more about WSDOT maintenance or construction activities that may impact traffic, please visit

WSDOT keeps people, businesses and the economy moving by operating and improving the state's transportation systems. To learn more about what we're doing, go to for pictures, videos, news and blogs. Real time traffic information is available at or by dialing 511.
To unsubscribe to WSDOT media releases please reply and type REMOVE in the subject line.

< Go Back