SELLWOOD, Ore. - Engineering crews will be moving the Sellwood Bridge to its new home over the Willamette River this weekend.
The Sellwood Bridge is being replaced and in order to give crews room to work on the new span, the old one is going to be slid out of the way and then used as a temporary detour for a couple of years.
"It's a big event for the community," said Project Manager Larry Gescher. "We try to make it a non event for ourselves - that's how we describe it. And that's all through the planning to make sure it's a non event."
The bridge has already been lifted off its main support beams (an 1,100-foot span weighing 6.8 million pounds has been jacked up several inches) in preparation for Saturday's big move. It could take up to 16 hours to move the section about 70 feet to the north - onto temporary support beams.
Project leaders say planning the move has been nerve-wracking but they believe moving day will be calm. They are scheduled to begin at 8:30 a.m.
This all started back in 2004 when engineers discovered cracks in the Sellwood Bridge. Crews have made several temporary fixes since then, but they knew all along that a permanent solution (building a new bridge) would be needed.
On Thursday, the old bridge was shut down to traffic and on Saturday the truss span will be moved in a full-day operation (it's expected to take about 16 hours to move an 1,100 foot section of the bridge). The bridge is scheduled to re-open as a detour on Thursday, Jan. 24.
Until then, the northern detour is Highway 43 to the Ross Island Bridge to Highway 99E and the southern detour is Highway 99E to Interstate 205 to Highway 43.
About the big move...
This particular method of building a new bridge is called a Shoo Fly. The idea is to shift the existing bridge out of the way so crews can build the new one right next to it. The benefits are that traffic can continue to flow and construction on the new bridge (slated for a 2015 completion) can be done all at once, instead of in stages. The animation below shows how the method works:
Why real-time won't be that exciting...
Contrary to what you might think, you won't actually be able to see the bridge move if you're watching it from the shore or from a boat a safe distance away. The move will be painstakingly slow.
The best way to see the whole operation is to watch the time lapse video that will be posted on the project website shortly after the move. You can also watch live video online if you want to see the progress at any given time.
However, if you do really want to see it in person, you can go to Sellwood Riverfront Park on the northeast side of the bridge at Southeast Spokane Street and Oaks Park Way. Just keep in mind that the park has very limited space for public parking and you may need to park several blocks away and walk in. Also, Southeast Spokane Street will be closed west of Southeast Oaks Park Way the day of the bridge move.
Boaters who want to watch the operation from the water will need to remain 500 feet away for safety reasons. The river under the bridge will be closed to boats the day of the big move and the sheriff's river patrol will be there to make sure no one gets too close.