SR 116 - Kilisut Harbor - Remove Fish Barrier

Project news

  • Cascade Bridge LLC crews working for WSDOT began construction on Monday, Aug. 5 on a 440-foot, two-lane concrete girder bridge spanning Kilisut Harbor just west of Marrowstone Island. 
  • View construction progress photos
  • A temporary bypass lane has been constructed at the site to allow for one-way alternating traffic with a signal through fall of 2020. 
  • Kayakers and pleasure craft will not be able to pass through the channel under the crossing at Kilisut Harbor. Due to safety considerations, the pedestrian trail to Isthmus Beach (from WSDOT right-of-way towards anything east of that location) is closed around-the-clock through fall of 2020. The trail west of that location is still open to the public. 

Needs & benefits

The goal of this project, spearheaded by the North Olympic Salmon Coalition (NOSC) and funded by its partners, is to restore historic tidal channels and fish runs between southern Kilisut Harbor and Oak Bay in Jefferson County by creating approximately 2,300 acres of productive habitat in Puget Sound. WSDOT will administer the construction contract to build the new bridge to replace the existing causeway, which has been identified as a barrier to fish. WSDOT and NOSC aim to re-establish major northern and southern migratory fish channels for juvenile and adult salmonoids, including ESA-listed Hood Canal summer Chum, Puget Sound Chinook and Puget Sound Steelhead.  

This work is part of WSDOT’s Fish Passage Barrier Removal Program, which identifies and removes barriers to fish caused by culverts under state highways. WSDOT works in partnership with the Washington Department of Fish and Wildlife to identify culverts that, once replaced, will increase fish habitat.

During construction, travelers will encounter reduced speeds and one-way alternating traffic at the work zone throughout the entirety of the project. Any total roadway closures will be announced in advance.

The End Result 

The new bridge will sport 11-foot lanes with four-foot shoulders. Crews will accommodate traffic while improving local fish migration and restoring the estuary to a more natural state.


  • May 2019: Advertise contract for competitive bids
  • June 19, 2019: Contract awarded to Cascade Bridge LLC.
  • Aug. 5, 2019: Construction begins
  • Mid-Sept. 2019: Traffic will alternate using a temporary signal around-the-clock through project completion
  • Fall 2020: Most work is complete


Financial Data for PIN 311605A
Funding Source Amount ($ in thousands)
2003 Gas Tax (Nickel Funding) $0
2005 Gas Tax (TPA) $0
Pre-Existing Funds (PEF) $12,610
CWA $29
Total $12,640


Dan McKernan
WSDOT Project Engineer

Tina Werner
WSDOT Communications


SR 116 Kilisut Harbor Thumbnail Image