In July of last year, the Oregon Department of Transportation restricted heavy trucks from crossing the Bridge of the Gods after discovering dozens of corroding bridge components that were in need of repair or replacement.
The Port of Cascade Locks completed the repair project in December 2013, allowing heavy trucks back onto the bridge, but is now facing new load restrictions that will affect truckers once again.
According to Paul Koch, interim general manager of the Port of Cascade Locks, restrictions will likely be in place within the next 60 days preventing short haul vehicles — also known as specialized haul vehicles — with more than four axles and weights over 50,000 pounds from crossing the bridge until further notice.
The restrictions stem from new federal regulations that require state transportation agencies to conduct load analyses on how specialized haul vehicles (SHV) impact bridge wear. According to a memo from Christy Jordan, the state’s Over-Dimension Permit Unit manager, SHV are “closely-spaced, multi-axle single unit trucks which were introduced by the trucking industry over the last decade.” They primarily consist of trucks with more than four axles, including drop axles, and Jordan’s memo cites “dump trucks, construction vehicles, solid waste trucks, and other hauling trucks” as examples of SHV.
Bruce Johnson, state bridge engineer for ODOT, explained that while a long-haul truck such as a 53-foot semi-trailer may weigh more than a SHV, its weight is spread out over a longer distance. A SHV, on the other hand, has a shorter wheelbase, meaning its weight isn’t spread out as much, which in turn concentrates greater stress on bridge components.
All public bridges in Oregon will be required to undergo the new load analysis for SHV, according to Johnson, a process that is still underway. If the bridges don’t pass, they will either have to make the necessary upgrades or repairs or will have to post signs indicating new weight restrictions for SHV.
Michael McElwee, executive director for the Port of Hood River, said he had not yet been contacted by ODOT about conducting an SHV load analysis for the Hood River Bridge, but was aware of the new requirements.
Johnson said on the Bridge of the Gods, the concrete approach spans at the ends of the bridge would have to be upgraded in order to comply with the new standards, which he expected “would be a very expensive project” that would likely cost several million dollars. He noted, however, that the work done on the $1.2-million project completed last year to strengthen the bridge and return it to its original 40-ton weight-limit was still “fine.”
Koch estimated that when the SHV restriction does go into place, it will affect approximately 15-20 trucks per month. Although the restrictions are an inconvenience to both the port and SHV drivers, Koch noted, “We don’t want to have vehicles that are going to increase or exacerbate our costs of maintenance.”
Johnson said the state doesn’t currently have to fund such a project for the Bridge of the Gods and suggested the Port of Cascade Locks would have to save its own money if it wanted to upgrade the bridge.
After last year’s repair project, which was financed through state, federal, and port funds, the port was required by ODOT to develop a 10-year maintenance and operations plan for the bridge to help keep it rated at 40 tons. The plan, which Koch said is scheduled for completion in September, calculates the port will spend $250,000-$300,000 annually on maintaining the bridge in order to keep the 40-ton weight restriction.
Earlier this year, the port increased tolls by 50 cents per axle to help fund bridge repairs and Koch wrote in a recent bridge status report that the Cascade Locks Port Commission “will be reviewing tolls every November in the future to ensure that tolls keep pace with necessary maintenance and repair.” He added the port is working with other ports in the Columbia River Gorge as well as the Gorge Commission “to develop the plans and strategies to be able to properly fund major repair items” on the Bridge of the Gods.