Sellwood Bridge completes huge milestone: Multnomah County re-opens span ahead of schedule

Thursday, 1/24/13 - 10:25 am

The temporary Sellwood Bridge is now open for traffic after a 6-day closure allowed workers to move a large portion of the span to make way for construction on the replacement bridge.

On Wednesday, Jan. 23, the first vehicles began crossing the bridge, ending a few days of detours. The temporary bridge opened to traffic 15 hours ahead of schedule. Multnomah County Commissioner Deborah Kafoury was in the first car to cross the bridge after it reopened. “It feels a lot like the old bridge did, but the new sections seem sturdier,” she said.

On Saturday, Jan. 19, workers began moving the 1,100-foot truss span of the 87-year-old bridge to the north onto new piers. It took 14 hours to move the span, which will create a detour bridge to make way for construction of the replacement bridge.

The truss span was the longest structure ever moved by specialty firm Omega Morgan of Hillsboro. While exact comparisons to other bridge moves are hard to find, experts say the Sellwood truss span was one the longest, oldest bridge sections ever moved in one piece.

Contractors moved the 3,400-ton truss span by pushing it with hydraulic jacks on rails along beams that linked the old piers with the new detour bridge piers. The process was a slow one, with workers moving the span a few inches at a time and then taking measurements to ensure it was properly positioned.

The big move was watched by hundreds of onlookers on the east and west banks of the river. Neighbors near the bridge hosted deck parties and Sellwood areas businesses sponsored a celebration with live music and free buttons that read “I Was Moved! Sellwood Bridge Jan. 2013.”

The detour bridge will minimize the impact of construction on local businesses and bridge users. It provides the following advantages over the original plan to build the new bridge in two phases:

Savings of $5 to $10 million in project costs
Reduction of construction time by one year
Improved safety by separating traffic from bridge construction
Reduced environmental impacts (due to less in-water work)

"We're continuing to make progress in completing this major transportation project," said Multnomah County Chair Jeff Cogen. "Watching the bridge move was an amazing moment. I'm very proud of the team that pulled off this engineering feat."

The old Sellwood Bridge, which in its former state was ranked a mere 2 on a scale of 0 to 100 on a sufficiency scale, was not built to withstand a major earthquake and had problematic cracks in the west approach. The new portions of the detour bridge have more seismic strength and the old west approach is not part of the detour bridge.

The permanent, replacement bridge is expected to open by the summer of 2015. For more information, visit www.sellwoodbridge.org.