Project overview
Reconnecting waterways where roads act as barriers is a priority for the state. In western Washington, this means building hundreds of fish-passable structures under state highways to create habitat that is essential for meeting fish recovery goals.
Two culverts in the interchange of Interstate 5 and State Route 104 in Mountlake Terrace are a barrier to fish migration through McAleer Creek, which drain into Lake Washington. This project will replace the culverts and rebuild the stream to reopen habitat and restore salmon populations. As early as spring 2033, a Design-Builder working for WSDOT will begin installing new fish-passable structures that convey McAleer Creek under Interstate 5.
What to expect
WSDOT will select a qualified design-build contractor to complete the design of the fish-passable structures for McAleer Creek under I-5. This project is combined into a single contract with a fish passage project on SR 524. Construction is currently anticipated to begin in spring 2033 and freeway closure needs will be determined by the type of structures and construction method proposed by the Design-Builder. Lane reductions on I-5 are expected to be necessary during select periods of construction to build the new culvert structure under I-5.
While the timing of culvert construction largely depends on the Design-Builder, we anticipate construction could occur periodically over the span of 2 to 3 years. The exact dates and details of travel impacts will be announced closer to the start construction.
As work progresses, we will post important project updates to our social media channels and our weekly GovDelivery e-newsletters.
This project will build two new fish passages at crossing centered around the I-5 interchange with SR 104 located in Mountlake Terrace, WA.
McAleer Creek crosses under I-5 north of the interchange with SR 104. Over the years the fish crossings at this location have been extensively modified from their natural condition. The existing structure is undersized for the stream which disrupts the flow of sediment and debris and reduces the quality of fish habitat. The current culvert also prevents fish access to the stream above the crossing, which reduces access to potential spawning and rearing habitat between the upper basin and Lake Ballinger.
As part of the project design, a total of two existing culverts will be replaced or removed. These structures are currently only 33 percent passable for native fish populations. The design of each barrier will focus on the removal or replacement of existing fish barrier structures with widened hydraulic openings to meet current fish passage requirements and introduce a new open-graded stream channel.
Fish in McAleer Creek
This work is part of WSDOT's fish passage program. Replacing the existing culverts and rebuilding the stream channel will expand healthy fish habitat, an important step in restoring fish runs and increasing populations. This benefits commercial seafood operations and recreational fishers and provides more food for the declining orca population. Additionally, replacing these fish barriers helps WSDOT meet its obligation to remove barriers under the 2013 U.S. District Court injunction.
