South Park Bridge Replacement is underway!

Artist's rendering of new South Park Bridge - after (courtesy of King County DOT)

If you’ve been around the South Park Bridge area, you are probably wondering “when is construction starting?”  The groundbreaking ceremony happened on May 5, and Kiewit-Massman, the joint-venture contractor that was selected for the project, received the “Notice to Proceed” on May 17. However, major construction begins on August 1, with the start of the ‘fish window’ (the time during which in-water construction is permitted).

As part of the process, a survey of the construction area was performed, which revealed three prehistoric archeological sites. One of these sites is located in the path of the new bridge. We know that around 1,000 years ago, the main channel of the Duwamish River flowed about 350 feet south of the existing channel, and the Duwamish people’s ancestors lived on the banks of the river (the channel was later filled in the early 20th century, since it has become an oxbow, or U-shaped bend in the river). A team of consultants dug several excavation pits in search of archeological artifacts, such as shells, stone tools, animal bones and hearths. Items found will be stored at the Burke Museum after they are analyzed.

South Park Bridge - before (courtesy of King County DOT)

The teams are gathering information about natural environmental information as well as some information about the people who used this area. So far, they’ve been able to determine that this was one of the seasonal fishing camps used by the ancestors of the Duwamish people. King County hosted tours of the archeological dig and put together a video with some highlights: Archeological project – South Park Bridge (courtesy of King County)

Fencing is up around the staging area at the south end of the bridge. This week, the contractor started working in the staging area, fabricating the formwork for the caissons (watertight structures that will be used to build the foundations of the bridge piers).

You can check out the County’s web page for more updates: http://kingcounty.gov/transportation/SouthParkBridge/ProjectUpdates.aspx