A group of cyclists approach to cross the ceremonial finish line at the opening ceremony for a new segment of the Lake to Sound Trail in SeaTac. (Andrew Engelson)

The project better links SeaTac and Burien into the regional trail network.

On a sunny Saturday in early June while noisy commercial jets made their approach to landing at SeaTac International Airport, King County and the City of SeaTac celebrated the opening of a new 2.2-mile segment of the paved Lake to Sound Trail. When complete, the 16-mile non-motorized trail will stretch from the southern tip of Lake Washington in Renton to the shores of Puget Sound in Des Moines. 

The trail, first conceived and funded in 2009, is a collaboration between King County and the cities of Renton, Tukwila, SeaTac, Burien, and Des Moines and represents a critical east-west corridor for cycling and walking. The full trail, currently about two-thirds complete, will eventually connect with four existing multi-use trails: Eastrail, Interurban, Green Lake, and Cedar River.

Lake to Sound Trail's Segment C adds 2.2 miles in Burien and SeaTac, as the map shows. The trail tracks SR 518.
Segment C completes part of the larger vision to connect Des Moines and Renton’s waterfronts. Unfinished segments remain in Tukwila and Renton. (King County Parks)

This new segment, a portion of what King County calls Segment C, travels through the city of SeaTac just to the south of the airport. Much of the 12-foot wide path is located on Washington Department of Transportation (WSDOT) land that will eventually contain an extension of State Route 509. The new segment features about 800 feet of elevated concrete boardwalk designed to protect existing wetlands. 

On hand at the opening ceremony — which included a ride from the Angle Lake light rail station by about two dozen members of the Cascade Bicycle Club — was David Shaw, a capital projects manager for King County. Shaw oversaw the creation of Segment C, which he said took a little less than two years to complete. King County oversaw the construction, and the trail itself has been given to the city of SeaTac to operate and maintain.

A group of over dozen people with their bikes on a wetland boardwalk segment of the trail.
Cascade Bicycle Club members were on hand to celebrate the opening of Segment C of the Lake to Sound Trail on June 7. (Andrew Engelson)

“A lot of the property is WSDOT [Washington State Department of Transportation] right of way,” Shaw said, “There were also a couple pieces of private property that needed to be purchased, that are now City of SeaTac-owned.”

Funding for this section of trail was provided by WSDOT, a grant from the Washington State Recreation and Conservation Office, and King County Parks Levy.

The character of the trail south of the airport will change dramatically once WSDOT completes its $2.8 billion expansion of SR 509, which will include four-lane flyover expressways. Adjacent to the trail, one can see a wide swath of bulldozed land where the freeway will eventually roar through here once complete in 2029. For now, though, the area is relatively peaceful, with a leafy canopy of cottonwoods and alders.

As an Alaska Airlines jet shrieked nearby on its final approach to the airport, SeaTac city council member Peter Kwon talked about the importance of the Lake to Sound Trail. “We have a need for bike lanes, especially in our communities near the airport impacted by noise, pollution, and traffic,” Kwon said. “We really need natural open spaces – it’s an even higher priority here than in other areas.”

Just south of SeaTac Airport, the trail runs through a busy flight path. (Andrew Engelson)

Shaw said that the county ranks its trail projects in terms of equity and social justice impact, and that this segment was at the very top of the list. “Historically, a lot of the investments have been in the north and on the Eastside, and maybe not as much in south King County,” he said. “That’s what this is really targeted towards — getting to these under-served communities, connecting them up, making sure they’ve got accessibility to the trail system.”

Shaw said that all of the Lake to Sound trail meets ADA requirements and is designed to encourage people who might otherwise not ride or walk in an area that’s historically been less than safe for pedestrians. South King County saw pedestrian fatalities nearly triple over a recent ten-year period. 

“Any time you can get people on a dedicated pedestrian, non-motorized facility, it’s going to increase their safety. It’s going to increase their comfort level,” Shaw said. “They’re going to get out there and use it more, shifting those trips from car trips to foot trips or bike trips.”

A promotional graphic highlights the value of the Lake to Sound Trail’s Segment in tying together Burien and SeaTac. (Leafline / King County Parks)

Robert Onishi, who lives in Auburn, was one of the Cascade Bicycle Club members who rode from Angle Lake station to the ribbon-cutting ceremony (although technically, rather than a ribbon, cyclists rode through a huge paper banner placed across the trail). 

Onishi, a volunteer trip leader for Cascade, says in some years he’ll cycle 5,000 miles or more, and sometimes on busy streets in South King County. “But that’s not the kind of thing that brand new cyclists or families with kids are necessarily going to want to start out with,” he said. “So, having accessible options that don’t involve fighting cars or worrying about traffic — that’s great.”

Cycling advocate Bob Svercl was also on the Cascade ride. “I wanted to make sure people knew, with this ride, that you have a light rail station right there,” he said. “You can get to Des Moines marina. You can go through here, on a nice paved path, all the way through Burien and SeaTac.”

In addition to being a short bike ride from the Angle Lake and Tukwila International Boulevard light rail stations, the Lake to Sound Trail’s new, contiguous 11-mile segment (which incorporates Segment C and a segment of the Des Moines Creek) is also accessible to Sounder S Line commuter rail and Metro’s RapidRide A Line bus. 

An empty field a pile of wood chips and a skid loader and a plan in the distance
The area Segment C traverses is both bucolic and airport-y. (Andrew Engelson)

“We’re making it safer and healthier for people in South King County to bike, walk, and roll to some of the best destinations our dynamic region has to offer,” King County Executive Shannon Braddock said of the new trail segment in a statement.

Shaw said that previous sections of the Lake to Sound Trail, which was first conceptualized and funded in 2009, include Segment B, west and north of the airport, which opened in 2018, and the 1.2-mile Segment A south of Skyway that incorporated parts of the Green River Trail, which opened in 2020.   

Four concrete boardwalks helped the county preserve wetlands along this segment. “Obviously, boardwalk construction is more expensive than building trail at grade on the ground. But from an environmental standpoint, it’s the right thing to do. It really reduces our impact,” Shaw said, noting that water, vegetation and wildlife are much more apt to thrive in those sections. 

Three people walk on the trail in the distance with thick trees on either side.
The boardwalk keep the trails out of the muck while preserving the wetland environment below. (Andrew Engelson)

Shaw also said that the completed trail segment will feature wayfinding signs and public art. There are no restrooms along this segment but there are some at the trailhead for the Des Moines Creek Trail further south.

Onishi is particularly excited about this no-man’s-land south of the runway being put to good use. “It’s beautiful, this underutilized area,” he said. “Much of this had been shut down for airport flyway traffic 30-some years ago.”

“It’s a great public use of that kind of space, especially as nicely put together as this is, and having some rationale about getting to and from the whole network of trails. That’s the key to usability, and the sort of thing that gets people out to use this system,” Onishi said.

Article Author
Andrew Engelson

Andrew Engelson is an award-winning freelance journalist and editor with over 20 years of experience. Most recently serving as News Director/Deputy Assistant at the South Seattle Emerald, Andrew was also the founder and editor of Cascadia Magazine. His journalism, essays, and writing have appeared in the South Seattle Emerald, The Stranger, Crosscut, Real Change, Seattle Weekly, the Seattle Post-Intelligencer, the Seattle Times, Washington Trails, and many other publications. He’s passionate about narrative journalism on a range of topics, including the environment, climate change, social justice, arts, culture, and science. He’s the winner of several first place awards from the Western Washington Chapter of the Society of Professional Journalists.