SR 203 - Loutsis Creek - Fish Passage

Project news

  • SR 203 will be closed 24 hours a day in both directions July 26-Aug. 26 at Loutsis Creek south of Duvall. Travelers will follow a detour.
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Needs & benefits

Loutsis Creek goes through a 5-foot culvert under SR 203 just south of Duvall. The culvert is difficult for fish to navigate at times because water levels can be too low or can move too fast. To improve passage for native and migratory fish, we will replace the culvert with an arched structure and build a more natural creek bed under the highway. This will improve fish runs and open an additional 3.1 miles of habitat for fish and other aquatic creatures.

This work will require this section of SR 203 to close for about six weeks starting in July 2020. The approximately 13,000 vehicles a day that use this portion of the highway will need to detour via Northeast 124th Street, West Snoqualmie Valley Road Northeast and Northeast Woodinville-Duvall Road. The detour adds about two miles to the trip. The crews will allow local access near the creek, but for safety reasons no one - including pedestrians and bicyclists - will be allowed to cross the work zone.


  • April 2020: Complete design and advertise project for competitive bidding.
  • May 2020: Contract awarded to Goodfellow Bros.
  • July 2020: Construction begins.
  • July 26, 2020: SR 203 closed at Loutsis Creek.
  • Aug. 26, 2020: SR 203 reopens at Loutsis Creek.
  • Fall 2020: Construction is scheduled to be complete.


The total estimated project cost is $8.2 million, using state and federal funding.


Tom Pearce
WSDOT Communications

A small map showing the location of Loutsis Creek near Duvall.