Culvert replacement underway at 35th Ave NE & Ballinger Way (SR104)
Friday, August 8, 2025
From the Lake Forest Park Stewardship Foundation
Anyone who has driven along Ballinger Way recently is well aware of the project to replace the Lyon Creek culvert beneath the roadway. Construction is happening up to seven days a week, with traffic control primarily occurring between 9pm and 5am.
Crews will perform site work and utility upgrades before installing the new culvert beneath SR 104, which will require extended road closures.
The following closures are planned during different stages of the project:
The following closures are planned during different stages of the project:
- Overnight, single-lane closures on SR 104, 35th Avenue Northeast and Northeast 185th Street with flaggers alternating traffic in each direction.
- A five-day closure along Northeast 185th Street.
- At least one overnight closure along 35th Avenue Northeast near SR 104.
- A 35-day closure along SR 104/Ballinger Way.
More details and an updated schedule for this project here
Most fish passage barriers are metal or concrete pipes, known as culverts. Culverts carry streams underneath roads, trails, and railroads. In King County, many culverts are decades old. Older culverts are often too small, too steep, or have a waterfall coming out of them.
Many culverts resemble firehoses, pushing water through at a high speed. This can make the culvert impossible for salmon to swim through. Over time, flows from the culvert can erode a deep hole in the streambed downstream. This prevents fish from being able to jump high enough to enter the culvert. The resulting waterfall out of the culvert creates a fish passage barrier.
Modern culverts look more like arches than pipes. They are big enough to allow the stream in the culvert to simulate natural stream conditions. This means that it's easy for fish and other aquatic life to move upstream or downstream through them.
See the graphic below from King County Department of Natural Resources: