State DOT project manager Brenden Clarke says the $30 million project is mostly federally funded and calls for replacing just the northbound span of the bridge.
"It has reached its service life," Clarke explained, pointing out corrosion on the 75-year-old span. "It's not unsafe, it's not structurally inadequate to hold traffic on it today, but as we all know it's not going to get any better."
The southbound span is newer and does not need to be replaced.
Crews will, however, put the old northbound span to good use while building the new one. They will move the aging section 60 feet to carry traffic in that direction.
Once the moving operation is finished Sunday, traffic will resume in both directions as contractors begin the year-long project to build a new span.
"It's going to have wider lanes, wider shoulders and a wider sidewalk," said Clarke. "it's part of our commitment to keep traffic moving smoothly in and out of Puyallup."
Crews will move the 1.5-million-pound span using the same technique employed over the Skagit River earlier this year. That operation entailed moving a temporary bridge into place after the old one collapsed. The Puyallup River span will not take as long.
Using powerful jacks, workers will lift the northbound span a couple feet, the slide it over three feet at time, repeating the lift-and-slide move until it's relocated 60 feet to its new position.
Barring any problems, traffic should open in both directions by 2 p.m. Sunday.
Detour signs will direct drivers around the closure. DOT managers suggest residents put off non-essential trips to help reduce congestion.
The DOT would like to recycle the old span once the project is finished in October 2015. The agency is trying to find a community that might want to use the structure as a foot or bicycle bridge in a park or other outdoor recreation area.