I-5/Tributaries to Friday, Lake & Chuckanut Creeks - Fish Passage

Project overview

This project removes and replaces several outdated culverts under I-5 roads for the Unnamed Tributaries of Friday Creek, Lake Creek, and Chuckanut Creeks in Whatcom and Skagit Counties.

WSDOT will replace outdated culverts with new structures for improved fish migration in the streams below as part of a statewide fish barrier correction program.

What to expect

Currently, this project is in the design phase. The length of closures needed at each construction site is still being determined. Timelines are subject to change as more design and permitting work progresses.

The locations for culvert replacement are:

• I-5 at Unnamed Tributaries to Friday Creek (milepost 241)
• Lake Samish Road at UNT to Friday Creek (Exit 240)
• I-5 at Lake Creek (Milepost 245.8)
• I-5 at Unnamed Tributary to Lake Creek (milepost 246.2)
• I-5 at Chuckanut Creek (milepost 246.8)
• Old Samish Road at Chuckanut Creek 

Construction of the Lake Creek crossing, located just south of the North Lake Samish Exit (Exit 246), will begin in 2025. During this phase, people traveling on northbound and southbound I-5 can expect nightly lane closures to construct temporary bypasses. Travelers on I-5 will then use the temporary bypasses through the summer while the Lake Creek crossing is under construction.

Work on the Unnamed Tributary to Friday Creek crossing is anticipated to start in the spring of 2025. To install the new structures, I-5 traffic will be temporarily reduced to one lane in each direction at two separate times for brief periods. Southbound I-5 will close for 15 days. During this time both directions of traffic will use northbound I-5 (one lane in each direction). Shortly following that closure, northbound I-5 will close for 12 days during this time both directions of traffic will travel on southbound I-5 (one lane in each direction). Travelers should expect extended back-ups during this time. Additionally, in either 2025 or 2026 crews will construct a new crossing under Lake Samish Road west of the Exit 240 (Alger) Interchange, which will require a two-week road closure.

Construction on the Chuckanut Creek crossing is expected to begin in the spring of 2026. During this time, travelers will use temporary bypasses for both directions of I-5 while new bridges are constructed. Old Samish Road will be closed while southbound I-5 traffic utilizes the county road. Once the I-5 bridges are completed, Old Samish Road will remain closed as a new bridge will also be constructed on that roadway for Chuckanut Creek. Restoration of the salmon stream channel habitat under the bridges is planned for the summer of 2027.

In 2027, work will begin at the North Lake Samish Interchange (Exit 246). During this phase, people traveling on northbound and southbound I-5 can expect nightly lane closures to construct temporary bypasses. Travelers on I-5 will then use the temporary bypasses through the summer while the Unnamed Tributary to Lake Creek crossing is under construction. A new culvert will be constructed across the existing lanes of traffic, and the southbound I-5 on and off-ramps will be reconfigured to accommodate this additional crossing. Most of the work will take place without any ramp closures. The new stream alignment will only intersect I-5 below the southbound I-5 on-ramp.

WSDOT and contractor crews will coordinate with local agencies and emergency services to minimize delays and keep traffic moving through work zones.