This image shows the old concrete pier where the bridge used to rest and the temporary metal one to which it was moved.

On January 19, 2013, the 87-year-old Sellwood Bridge was moved (translated, in engineer jargon) 33 feet north at its east end and 66 feet north at its west end to make way for a new bridge. The translation took 14 hours and was accomplished by lifting the 1,100-foot-long, 3,400-ton (6.8 million pounds) truss span off its concrete piers and pushing it by means of hydraulic jacks along translation beams to rest on its new temporary bents. This would have been fascinating to watch, but what is visible now is the work on the new bridge.

A more detailed engineering explanation plus some time-lapse videos can be found at http://www.sellwoodbridge.org/?p=bridge-move-and-detour-bridge and http://www.sellwoodbridge.org/?p=frequently-asked-questions-about-the-sellwood-bridge-move-and-de

A view of this venerable bridge from the south side (taken with the Leica):