I crossed the Hood River White Salmon Bridge this weekend to take a look at the damage to the lift span.  It was hard to figure out which steel was from the original fixed span 1924 bridge and which steel was added in 1939.  This image from February 1940 and this image from April 1940 tell the story when compared with this image from 1924.  While the truss which spans the shipping channel is the original 1924 structure, three things had to happen to make it possible to lift this originally fixed component:

•  The piers at either end of the span needed to be reinforced to handle much more weight.  The tower includes concrete counterweights which equal the mass of the central span, so that portion of the load is effectively doubled.  We have images which show them adding a shell of concrete around the original piers, which are now larger than all the other bridge piers.

•  The two towers had to be constructed, each with a counterweight, drive motor, cable, pulley and counterweight capable of pulling up on the central span.

•  A “gateway” of sorts was added at each side of the 1924 truss so instead of two points resting on the piers, each side has a box structure which provides stability and strength for the lifting actions.

In my quick view as I drove across it looked like most of the damage was to 1939 steel, not 1924 steel.  It looks like the original steel truss is intact, but the box structure which was added to it so it could be lifted will need repair.  I’m not sure if the lift towers themselves were also damaged.  Current plans call for work to be done during 7 pm to 7 am bridge closures every evening for the next two weeks.

Hopefully these repairs will be completed on schedule, adding one more chapter to the one hundred year history of this structure.  I know this period will be remembered as one of significant hardship for many.  The construction of this bridge brought Hood River, White Salmon and Bingen together in many ways as a single community.  Its temporary absence  means people can’t get to work, daycare, shopping, and medical appointments.  I wonder if the people who built this bridge imagined it would transform the communities in such a fundamental way?

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