After years of planning, the Puget Sound Gateway Program took a major step toward completing the SR 509 corridor with the Washington State Department of Transportation’s selection of Guy F. Atkinson Construction as the ‘apparent best value’ winner for the contract to build the next large phase of the project.
WSDOT announced that the $263,975,895 million price proposal resulted in the “apparent best value” for this design-build project. A design-build contract combines final project design and construction into a single contract. The “apparent best value” determination is based on a combined score for the design proposal and project price.
The SR 509 Completion Project was originally funded over a 16-year timeline with targeted completion in 2031. The state Legislature advanced Program funding in the 2019 session, moving project completion to 2028.
WSDOT says that the work, under the Puget Sound Gateway Program’s State Route 509 Completion Project will include:
- Building the first of 3 new miles of SR 509 Expressway
- Constructing new freight connections from the Kent Valley to Interstate 5 and Sea-Tac International Airport
- Creating additional access south of the airport to business centers in SeaTac and Des Moines
“We’re building a large and complex project that includes a new highway and new connections to I-5, which is rare in an urban environment,” said John White, administrator of the Puget Sound Gateway Program. “Guy F, Atkinson Construction stood out for its creative ideas, accelerated construction schedule and commitment to minimizing disruption to the traveling public. We look forward to working with them.”
Here’s a video about the project:
Here’s more from WSDOT:
Key features of this stage of construction
The contractor will complete design work in 2021. Construction will start by early 2022 and is scheduled to wrap up by the end of 2025. The work includes:
- The first mile of a new SR 509 Expressway between I-5 and 24th Avenue South in SeaTac
- A new interchange at 24th Avenue South in SeaTac that connects to the new SR 509 Expressway
- A new, wider South 216th Street bridge with improved access over I-5 for people who drive, bike and walk
- New ramps along I-5 that connect to the new SR 509 Expressway
- A new I-5 underpass at Veterans Drive in Kent, which provides a direct connection to the manufacturing and warehousing area in the Kent Valley
- A reconfigured I-5/SR 516 interchange that improves mobility for people who drive, walk, bike, and use transit
Other construction stages of the SR 509 Completion Project
The first phase of the SR 509 Completion Project is underway and partners with Sound Transit to build a new SR 99 bridge as part of Sound Transit’s Federal Way Link Extension work. Combining these projects helps reduce the construction impact to nearby communities.
The final 2 miles of the new SR 509 Expressway between 24th Avenue South and 188th Street in SeaTac will be built under a separate contract, scheduled to be advertised in 2023 and completed in late 2028.
The SR 509 Completion Project was originally funded over a 16-year timeline with targeted completion in 2031. The state Legislature advanced Program funding in the 2019 session, moving project completion to 2028.</p
- Stage 1a: Constructs a new bridge over SR 99 near South 208th Street; This work will be done by Sound Transit and will take about two and a half years to complete.
- SR 509/I-5 to 24th Avenue South – New Expressway Project (formerly Stage 1b):
- Reconstructs the I-5/SR 516 interchange
- Builds new SR 509 ramps to and from I-5
- Constructs a new interchange at 24th Avenue
- Builds a new South 216th Street I-5 overpass. This new overpass provides pedestrian and bike access, which does not exist on the current 216th Street bridge.
- SR 509/24th Avenue South to South 188th Street – New Expressway Project (formerly Stage 2):
- Constructs the majority of the new SR 509
- Adds a southbound auxiliary lane on I-5 between SR 516 and South 272nd Street between 2024 and 2028.
About the Puget Sound Gateway Program
The SR 509 Completion Project in King County and the SR 167 Completion Project in Pierce County are part of WSDOT’s Puget Sound Gateway Program. Both projects are designed to complete essential connections to the ports of Tacoma and Seattle and ensure that people and goods move more reliably through the region.
The Puget Sound Gateway Program was authorized by the Washington State Legislature in 2015 and is funded with federal funds, local contributions, WSDOT’s Connecting Washington account and future toll revenues.