Project Summary
The 108-acre Meadowdale Beach Park, 24 miles north of downtown Seattle, in Snohomish County, Washington, sits adjacent to the Puget Sound Delta and Lunds Gulch Creek, which flows through the park. The park receives an estimated 65,000 visitors and hosts several environmental and recreational education programs annually.
The land’s rich history includes use and stewardship by the Coast Salish people and eventual ownership by the Great Northern Railroad, which built its first track in 1891 and became BNSF Railway Co. much later. The region’s logging industry later necessitated the addition of a second track. By 1968, Snohomish County had acquired the property, and in 1988, the county opened the park and signed a BNSF agreement that allowed the public to access the beach through a box culvert passing under the tracks, which separates the beach from the park area.
A past worth preserving
The connection between Lunds Gulch Creek and Puget Sound, known as a barrier embayment, is historically, culturally and environmentally significant. Embayments are protected estuaries and lagoons that play a major role in providing passage for anadromous salmon and trout migration. They also serve as essential rearing grounds for juvenile fish and enable natural sediment transport.
“Hanson did an outstanding job supporting railroad design work for this project. Hanson’s relationship with BNSF has been a huge plus for this project. Their suggestion early on to design the project to be in line with BNSF’s construction capabilities allowed a big win for Snohomish County when BNSF agreed to use their crews rather than a county-procured contractor.” - Logan Daniels, Snohomish County Parks and Recreation lead engineer
When the railroad’s embankments were built in the late 19th century, many stream crossings were restricted to culverts sized to maintain drainage and prevent flood impacts. An unintended consequence of this was the blockage of the embayments and the degradation of habitat quality due to Embankment construction led to the loss of most of the embayments along the eastern shore of Puget Sound.
Since Meadowdale Beach Park’s opening, the location of the BNSF-owned double tracks limited beach access to a 6-foot-by-6-foot box culvert, which park visitors had to share with passing stream water and fish. In addition to the environmental impacts noted above, the culvert created an access challenge for park users, some of whom resorted to trespassing over the railroad tracks when the culvert was inaccessible due to high stream flow, which was illegal and dangerous. Americans with Disabilities Act (ADA) accessibility was nonexistent, even under the best conditions.
Hanson design helps upgrade park
Snohomish County enlisted Hanson to contribute railroad bridge design and construction management for an approximately $16 million project to restore the park’s estuaries. The restoration of the 1.3-acre site established a rearing habitat for chinook, chum and coho salmon and cutthroat trout between Lunds Gulch Creek and Puget Sound. The Puget Sound chinook is a threatened species under the U.S. Endangered Species Act.
The project involved replacing a 6-foot-wide culvert and 128 linear feet of railroad embankment with a five-span rail bridge featuring a 100-foot opening allowing juvenile salmon access to a pocket estuary where they can grow.
Hanson also provided design for a temporary construction embankment, access road improvements, temporary shoring between the two tracks, the demolition of a box culvert and the removal and disposal of track embankment, as well as grant support.
The project presented multiple challenges, including project stakeholder concerns that BNSF would not support the project. To address this, the Hanson team proposed a revised bridge design that allowed BNSF bridge forces and equipment to install the bridge and reduce impacts to BNSF train operations.
The county also experienced delays in obtaining the temporary occupancy permit for surveying and geotechnical investigations; however, Hanson employed key BNSF contacts to contact decisionmakers and clear the logjam so the county could proceed with the field investigations and avoid further project delays.
Bright future for fish and beachgoers
In addition to a pathway for juvenile salmon, the bridge improves fish habitat, sediment transport, beach park access and safety in the area.
Hanson has presented on the project at events held by organizations including the American Railway Engineering and Maintenance-of-Way Association and the Railroad Environmental Conference. The Seattle Times also published an article about the project.