what we do


Providing safe, convenient routes for pedestrians and bicyclists

Non-motorized facilities weave our communities together, improve livability, and promote healthy lifestyles. Parametrix designs safe spaces dedicated to people and seamless connections to places where people live, work, and play.

Lake to Sound Trail
Lake to Sound Trail 
Renton to Des Moines, Washington
Client: King County Parks

The 16-mile multi-use Lake to Sound Trail is being built in four segments and will ultimately span from the south end of Lake Washington to the shoreline of Puget Sound. It offers a non-motorized transportation alternative to South King County and strengthens regional trail connections between communities, making it convenient to walk, run, or bike to high-capacity transit.
Segment A is 1.1 miles, from Fort Dent Park in Tukwila to the Black River Riparian Forest in Renton, where users can catch glimpses of the largest heron rookeries in the region. The trail crosses over the Black River via a new pedestrian bridge, traverses under high-speed rail, and includes a new HAWK pedestrian signal that allows users to cross a heavily traveled industrial road. Segment B is 1.5 miles connecting SeaTac and Burien along Des Moines Memorial Drive. The design includes a boardwalk over Walker Creek and associated wetlands, lease agreement, and construction approvals from WSDOT for traversing under SR 509, and coordination with Seattle City Light for the undergrounding of utilities. Segment C, under construction, will connect Segment B to the Des Moines Creek Trail. It will traverse a densely developed area requiring coordination with a number of stakeholders, including WSDOT for use of a portion of the right-of-way intended for an extension of SR 509, as well as the cities of Burien, Normandy Park, and SeaTac. The final segment is in early planning stages.

  • ACEC Gold Award for Social, Economic, and Sustainable Design



  • Lake to Sound Trail

    Lake to Sound Trail

  • Oregon Coast Trail Action Plan

    Oregon Coast Trail Action Plan

  • Alameda Drain Trail

    Alameda Drain Trail

  • Dona Larsen Park Multi-Use Pathway

    Dona Larsen Park Multi-Use Pathway

  • Mica Peak Trail

    Mica Peak Trail

  • East Lake Sammamish Trail | Parametrix

    East Lake Sammamish Trail


“I wanted to thank you and the Parametrix team for the outstanding support you have provided the County on the East Lake Sammamish Trial Project. Parametrix’s complete understanding of the controversies surrounding the East Lake Sammamish Trail Project, the complexities in dealing with multiple jurisdictions, and the difficulties with regard to constraints surrounding the County’s budget has been critical in Parametrix and the County’s ability to identify and quantify risks associated with the project’s cost and schedule.”

Gina Auld, King County