I-5 fish passage project construction begins Wednesday, April 30, south of Bellingham

BELLINGHAM – A three-year project to remove 17 barriers to fish migration along a 6-mile stretch of Interstate 5 in Skagit and Whatcom Counties will begin construction Wednesday, April 30. 

Contractor crews working on behalf of the Washington State Department of Transportation will begin overnight work on I-5 south of Bellingham at 8 p.m. Wednesday, April 30.

Construction is expected to last until 2027, as crews will remove 17 barriers and replace them with 10 new structures that will allow fish to swim freely beneath I-5 and adjacent Whatcom and Skagit county roads near Lake Samish. This work will improve stream connectivity along Lake Creek, Chuckanut Creek and unnamed tributaries to Friday Creek and Lake Creek.

What to expect

From April through October 2025, construction will occur at Lake Creek near the north end of Lake Samish. During this time, travelers should expect to see:

• Nighttime single-lane closures on I-5 from 8 p.m. to 5 a.m., starting Wednesday, April 30, through early June.
• Temporary two-lane bypass roads used for northbound and southbound I-5 traffic during the summer.
• Occasional nighttime rolling slowdowns, where traffic is briefly held or slowed to create a safe work zone ahead.

Later in 2025, construction may occur at the unnamed tributaries to Friday Creek near Alger. More information will be shared once the schedule is finalized.

Temporary bypass roads

In 2025, bypass roads will be built to divert northbound and southbound I-5 traffic around the Lake Creek work zone (milepost 245). An advisory speed reduction will be set once traffic is shifted to the bypass roads. 

Restoring fish habitat

This project is part of WSDOT’s efforts to improve fish passage under state highways. 2013 federal court injunction requires the state to significantly increase its efforts to remove state-owned culverts that block salmon, bull trout and steelhead habitats.

People can find real-time updates by visiting the Friday, Lake and Chuckanut Creeks Online Open House and the WSDOT Travel Map.