SR 202 Evans Creek & Patterson Creek Fish Passage
Hamilton was the design-builder on this fish passage project that replaced three existing fish barrier culverts crossing SR 202 with fish-passable water crossing structures over two weekend closures. The project included multiple sites, substantial roadway work, stream restoration, traffic control, and landscaping. Stream restoration features included natural channel design, large woody material (LWM), bank stabilization, and associated wetland creation. This WSDOT design-build fish passage project resulted in opening up 11.25 miles of stream to provide high quality aquatic habitat.
Work was accomplished with limited duration closures utilizing accelerated bridge construction techniques of pre-casting the culvert components off-site, then assembling them on-site. The first closure completed the installation of the Patterson Creek crossing in a 54-hour period. Two remaining separate locations, east and west tributaries to Patterson Creek, were completed simultaneously within a 56-hour period. Careful preplanning, pre-staging, and pre-fabrication of components reduced the duration of construction.
The success of this project relied on collaboration between the Hamilton design-build team, WSDOT, the Muckleshoot and Tulalip Tribes, Washington Department of Fish & Wildlife (WDFW), the U.S. Army Corps of Engineers, public utility companies, suppliers, private homeowners, and subcontractors. Substantial coordination was needed with residents to minimize impacts, including using only two of the three allowable weekend closures to remove the three barriers.
Major Project Elements