Project overview
Reconnecting waterways where our roads act as barriers is a priority for the state. In western Washington, that means building hundreds of fish passable structures under state highways to create habitat essential for meeting fish recovery goals. Beginning in 2025, WSDOT will build multiple structures that may include new bridges on I-90 and local roads near Issaquah to restore natural stream conditions in Lewis, West Village Park and Schneider creeks.
What to expect
I-90 travelers and users of local roads can expect:
- Traffic shifts on Westbound I-90 near the 17th Avenue Northwest and Lakemont Boulevard interchanges.
- Closures along Northwest Sammamish Road for utility work just west of Lake Sammamish State Park.
- Overnight lane reductions.
- Detours around closed on- and off-ramps and surface streets.
In July 2026, WSDOT will close Northwest Sammamish Road to build a new bridge over Schneider Creek. Prior to that work, beginning this spring, expect closures on that road west of Lake Sammamish State Park while utility providers relocate their services.
This project combines several fish passage projects into a single contract. Originally it included fish passage work on SR 900, but that work has been shifted to a separate new project, likely to be advertised in late 2026.
WSDOT will improve fish passage under I-90 by building new bridges at Lewis and Schneider creeks west of Issaquah.
To protect and restore fish runs, WSDOT is correcting fish barriers found under state highways. Since 1991, when WSDOT created a dedicated program, hundreds barriers have been corrected, opening more than 1,200 miles of fish habitat.
Replacing the culverts that carry Lewis, West Village Park and Schneider creeks under I-90 and adjacent surface streets with new fish passable structures increases the likelihood of fish migration in these streams.
Opening habitat allows more salmon and steelhead at all life stages, including juveniles that aren’t yet strong swimmers like adults, to access important spawning and rearing habitat, including areas that haven’t been accessed in years.
Improvements to fish passage also benefits commercial seafood operations, recreational fishers and provides more food for our declining orca population. In addition, replacing these culverts helps us meeting our obligation to remove barriers under a 2013 U.S. District Court injunction.
About the creeks at I-90
Lewis Creek runs under I-90 near Lakemont Boulevard. It serves as a tributary to Lake Sammamish. The culverts under I-90 are considered completely impassable. Lewis Creek is home to Chinook, coho, resident trout, steelhead, sockeye and sea-run cutthroat. Replacing the existing culverts with a new fish passable structure will result in a potential habitat gain of more than 2.5 miles.
West Village Park Creek flows under I-90 just east of Southeast 51st Street. As a tributary to Lake Sammamish, the creek is home to Coho, resident trout, steelhead, and sea-run cutthroat. The culvert carrying the creek is considered completely impassable. There is a potential habitat gain of more than a half-mile by replacing the existing culvert with a new fish passable structure.
Schneider Creek is located near the west edge of Lake Sammamish State Park and runs under I-90 as well. It is only 33% percent passable. The Coho, resident trout, steelhead, sockeye salmon and sea-run cutthroat runs will be better served by a larger structure, offering a potential gain of nearly three-quarters of a mile of new habitat.
