Welcome to the Puget Sound Gateway Program's "SR 509 Completion Project".
This Project runs from the SR 509 interchange at South 160th Street, in Burien, to the I-5
interchange at South 272nd Street, in Federal Way.
The purpose of this project is to ease congestion on I-5 near Tukwila, add a southern access
point to the Sea-Tac International Airport, and improve travel between industrial districts
for general purpose traffic and trucks.
This will be accomplished by building a new, four-lane, three-mile long "SR 509 Expressway"
to bypass I-5, SR 99, and local streets.
The project will be constructed in 3 stages - Stage 1A, Stage 1B, and Stage 2.
Stages 1A and 1B have already started construction.
Stage 1A will be completed in 2022.
Stage 1B should be completed in 2025.
Stage 2 is expected to start construction in late 2024,
and the entire project should be completed by 2029.
Stage 1A involves the construction of a new bridge on SR 99.
It is being constructed by Sound Transit's Federal Way Link Extension project, which
extends light rail from the Angle Lake Station in the City of SeaTac to the Federal Way Transit
Center.
This new rail line is integrated with and compliments the SR 509 Completion project.
Stage 1B will reconstruct the SR 516 / I-5 interchange, replace the 216th Street Overpass,
and build the first mile of the new SR 509 Expressway.
The I-5 / SR 516 Interchange reconstruction will include a new Veterans Drive/I-5 underpass.
This will provide a direct connection to the manufacturing and warehousing areas in the
Kent Valley.
New multi-use paths and bus pullouts will improve access and safety for pedestrians,
bicyclists, and transit riders.
A new 216th Street overpass will be built to make room for new direct access ramps and
several new "auxiliary" and "collector-distributor" lanes that will run along I-5, below the bridge.
The new direct access ramps will connect I-5 to the new SR 509 Expressway.
At 24th Avenue South, the new four-lane SR 509 Expressway will have a northbound off-ramp
leading to 24th Avenue South and a south bound on-ramp heading towards I-5.
Stage 2 consists of two parts.
One part will add a southbound auxiliary lane to I-5 from the vicinity of the SR 516 Interchange
to the interchange at the South 272nd Street off ramp.
The other part will extend the new SR 509 Expressway from 24th Avenue South
to the interchange at South 188th Street.
And Stage 2 will include roundabouts and ramp improvements at both the South 188th Street
Interchange and the South 160th Street Interchange.
In addition, WSDOT has funded a 1.8 mile portion of the "Lake to Sound Trail."
This is a 16-mile long, non-motorized trail extending from Lake Washington to the Puget
Sound shoreline.
The trail project is under construction and being administered by King County Parks.
This 1.8 mile portion of the trail will interface with the new SR 509 Expressway near South
200th Street, Des Moines Memorial Drive, and the South 188th Street Interchange and will
be completed in 2023.
The Puget Sound Gateway Program's "SR 509 Completion Project" is a strategic investment
in Washington State's freight mobility, multimodal growth, general purpose traffic, and safety.
From a new four-lane expressway with interchanges, direct connections to future light rail stations
and an extended pedestrian trail, this project will benefit all users, both now and well
into the future.
Thanks for watching!