PORTLAND, Oregon — UPDATE: The Oregon Department of Transportation announced it has postponed the I-5 Interstate Bridge Trunnion Replacement Project to keep the highways as clear as possible for wildfire evacuees.
The project was scheduled to begin Saturday, Sept. 12 and last for nine days. ODOT said it will work with the Washington State Department of Transportation, contractors and the U.S. Coast Guard to discuss when the project will commence.
PREVIOUS STORY: Starting September 12, 2020, the northbound span of the interstate bridge, will close for eight days as crews replace a cracked trunnion and other parts that help lift and lower the bridge.
The interstate bridge is located on Interstate Five, where it connects Oregon and Washington across the Columbia River.
The equipment that lifts the bridge includes sheaves, sheave hoods, trunnions, and cables.
Each tower has two sheaves, like a giant wheel. They are about 12 feet in diameter. Each sheave has an axle called a trunnion that supports the weight of the bridge and counterweights.
In 1999, a crack was discovered in a trunnion on the northbound bridge's South Tower. The bridge is currently safe and the crack is regularly monitored.
We are replacing the trunnion to keep the bridge in working order. Our top priority is the public safety. Because this work takes place overhead, the northbound bridge must close to keep drivers safe and to provide access for construction crews and heavy equipment.
During the closure period travelers crossing the Interstate Bridge, in both directions, will share the three existing lanes and sidewalk on the southbound span.
A movable concrete barrier will allow two lanes of traffic to travel in the heaviest direction. For the morning commute, two southbound lanes will travel into Portland and one northbound lane into Vancouver. And for the evening commute, two northbound lanes will travel into Vancouver and one southbound lane into Portland. Crews will move the concrete barrier mid day and again overnight.
Four ramps withing the project zone will close during construction. These ramp closures are necessary to control traffic flow in the construction area to ensure a safe travel and work zone. Even with lanes remaining open, both directions throughout construction, travelers should expect heavy traffic, congestion, and long delays on I-205, I-5, I-84, and surrounding local streets
During the closure, if travel habits do not change, travelers can expect up to 16 hours of congestion a day. And up to four miles of congestion on either side of the Interstate Bridge. Everyone can make this project a success and ease congestion by changing travel habits, such as carpooling, taking a bus or transit, or delaying trips.
For the most up to date information, visit interstatebridge.org and sign up for project alerts.
