Prior to deck replacement, five pile caps were replaced.  This required jacking the entire bridge using 8 hydraulic jacks, cutting the old caps into short sections using a chain saw and then inserting a new 30-foot long beam from the side.  Note the steel I beam sections in between the piles.  During jacking, these beams spread the bridge's weight over a larger surface to reduce the likelihood of jacking failure.  The silt found between the piles in incapable of supporting more than 2,000 pounds per square foot.

After insertion work was completed, the caps were strapped to the piles to restrict movement during a seismic event.  Work was completed in just two weeks.

Replacing a timber deck on a railway bridge can be hazardous. Workers are restrained with safety harnesses slowing their progress. Rails are laid across the bridge as the timber deck is placed and additional materials are delivered by rail-mounted crane.

The new deck consists of 141 10 inch square by 12 feet Douglas Fir ties treated with ACZA (ammoniacal copper zinc arsenate) and stained black.  Creosote products were banned on this project by the Washington State Department of Fish and Wildlife.

The rail is 112 lbs/yard, slightly heavier than the "original" 90 lb/yard rail. The heavier rail was applied to help spread load better through great beam strength in the rail section, and by the use of larger, double shoulder tie plates.

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