Welding crews work on the Hood River-White Salmon Bridge

Welding crews work on the Hood River-White Salmon Bridge.

The Oregon Dept. of Transportation (ODOT) will impose a lower load rating on the Hood River-White Salmon Interstate bridge effective March 3, the Port of Hood River announced in a press release.

The new load rating is the result of a directive by the Federal Highway Administration (FHWA) requiring all states to evaluate the structural capacity of all bridges to carry Specialized Hauling Vehicles (single-unit trucks with closely spaced, multiple axles) and other load factors. Extensive structural analysis was carried out by ODOT’s engineers in 2020 on the bridge as part of this nationwide effort. The bridge is a steel truss structure that is nearly 100 years old. ODOT’s structural evaluation identified deficiencies in some bridge components that required the lower load rating.

The current maximum vehicle weight for the bridge is 80,000 pounds, or 40 tons. The updated load rating will affect most classes of trucks. It will be posted at 24 tons for Type 3 vehicles, 32 tons for Type 3S2 and Type 3-3, 22 tons for the SU4, 24 tons for the SU5, and 25 tons for the SU6 and SU7 vehicles.

The Port’s bridge engineering firm, HDR, will immediately begin a detailed analysis of ODOT’s structural evaluation to identify strengthening measures needed to restore the current weight limit, and the potential cost of such measures.

“The engineering effort to determine if repairs are possible will take several months,” said Port Director Michael McElwee. “The Port Commission will then need to determine whether it is financially feasible to carry out those repairs.” HDR may also recommend live load testing portions of the bridge which may reduce the extent and cost of structural upgrades.

Port staff have been in contact with local commodity haulers and shippers and will work to ensure that businesses impacted by this new weight limit are kept informed as the Port’s response actions are carried out.