News | Oregon

Q&A: Sellwood Bridge Reopens After Being Moved

OPB | Jan. 23, 2013 4:45 p.m. | Updated: Jan. 24, 2013 11:20 a.m. | Portland

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Portland commuters will be happy to learn the Sellwood Bridge opened Wednesday afternoon — ahead of schedule. Kristian Foden-Vencil has been following the work and joined Eve Epstein in the studio to discuss the project.

Traffic resumed Wednesday afternoon on the Sellwood Bridge, half a day earlier than forecast. The old structure, in a new location, now serves as a temporary bridge while its replacement is constructed in its original position.

Traffic resumed Wednesday afternoon on the Sellwood Bridge, half a day earlier than forecast. The old structure, in a new location, now serves as a temporary bridge while its replacement is constructed in its original position.

Vince Patton / OPB

Eve Epstein: So, the bridge was scheduled to open Thursday morning at 7 a.m. But here we are, with cars crossing the bridge on this afternoon’s commute. Why? 

Kristian Foden-Vencil: Well, I’m told Saturday’s move went very well. The bridge didn’t groan or creak, it simply slid quietly into place. 

That apparently is what engineers were hoping for. Banging or screeching indicated breaking or twisting steel. 

Anyway, I understand engineers checked the bridge in four different ways: with lasers and strain-gages, to make sure it remains straight; with GPS, to make sure it’s in the right place; and with people crawling all over it, to make sure no rivets popped or steel cracked.  The fourth part, and the part that’s apparently took the longest to verify, is the mathematics. Someone has to re-calculate all the loads and stresses, just to make doubly sure. 

EE: So, is it safe? For example, can the buses and trucks that were banned a few years ago, now use the bridge again. 

KFV: Well the short answer is yes, the bridge is safe. And no, anything over 10 tons can’t go on it. 

One new safety feature: the new pilings the bridge stands on are up to current earthquake standards, even if they are temporary. Whereas the old bridge supports were not. 

Secondly, the long green steel box that made up the deck of the old bridge was always fine.  The problem was the two access ramps leading up to the bridge. The one of the westside stood on a slow moving landslide. It was badly twisted and cracked. In fact, it’s already been demolished. 

The ramp on the eastside is still in partial use and that’s why big trucks still can’t use the bridge.

EE: 30,000 people a day use that bridge, I understand. Do authorities think they’re all coming back?

KFV: I asked Mike Pullen, Multnomah County’s go-to guy on the bridge, and he says, yes.

Mike Pullen: We do expect most people who used the Sellwood Bridge previously will be using the detour bridge. I’ve heard from a few people anecdotally that they wonder, “Wow, this bridge was so old and you moved it. Is it really safe?” We think it’s safer than the old Sellwood Bridge for a number of reasons. And we’re seeing a lot of traffic back on it already.

KFV: Pullen says he was the first person to drive over the new bridge, with Multnomah County Commissioner, Deborah Kaufory. He says it was very smooth and felt more solid.  One other point, he says the speed limit has been dropped from 30 miles per hour to 25 — that’s because a couple of turns have been incorporated on the ramps. 

EE: So, what’s next?

KFV: Well the new detour bridge will be there for three years as the new bridge is built where the old bridge used to be.  No work can be done in the river until July, because of fish.  But now workers are going to start digging out the old tree stumps and earth along Highway 43, to make way for a new improved junction. 

EE. Thank you. 

KFV: My pleasure. 

 


OPB’s Geoff Norcross spoke with Pullen once again on  Thursday a.m. You can hear their conversation below.


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