It may only be February, but construction is already ramping up for the State Route 509 Completion Project, with closures coming starting Monday, Feb. 6, 2023.
Starting Monday, Feb. 6, contractor crews working for the Washington State Department of Transportation will kick off a series of lane, ramp and intersection closures in the Kent/Des Moines area as part of an effort to improve mobility and reduce traffic noise to nearby homes.
People traveling through the area should prepare for overnight lane reductions on Interstate 5, a two-week closure of the 30th Avenue South intersection with SR 516 and a revised southbound I-5 off-ramp to SR 516.
30th Avenue South at SR 516 closure:
A two-week closure of 30th Avenue South, on the north side of SR 516 will allow crews to widen a short section of westbound SR 516 in preparation for reconfiguring the I-5/SR 516 interchange.
- 8 a.m. Monday, Feb. 6 to 10 a.m. Sunday, Feb. 19 – The north leg of 30th Avenue South will be closed at SR 516.
- Drivers will not be able to make right turns on or off 30th Avenue South. A signed detour will be in place.
- 30th Avenue South on the south side of SR 516 remains open.
Partial weekend closure of southbound I-5 ramp to SR 516:
The closure of 30th Avenue South allows crews to expand and improve the existing southbound I-5 off ramp to SR 516. This work will require a partial weekend closure of the ramp.
- 10:30 p.m. Friday, Feb. 24 to 10 a.m. Sunday, Feb. 26 – The southbound I-5 ramp to SR 516 will be closed around the clock.
- A detour route will be in place.
When the ramp reopens, lanes will be shifted to the right. This shift provides crews with a safe work zone to convert the ramp to five lanes and begin work on a new tunnel under I-5 as crews continue to reconfigure the interchange to support the completion of SR 509.
I-5 lane closures for noise wall work:
Installation of a new noise wall on northbound I-5 will require nightly lane closures.
- 7 p.m. Monday, Feb. 6 to 4:30 a.m. Friday, Feb. 24 – The three right lanes of northbound I-5 between South 216th Street and Military Road South are closed nightly.
- The left general-purpose and HOV lanes will remain open.
- People traveling on I-5 during this time should prepare for delays or take an alternate route.
The new noise wall in this section of I-5 will protect nearby residents from additional traffic noise as the new I-5/SR 516 interchange is complete. The noise wall consists of 79 different panels and up to 12 panels will be placed each night. A southbound wall in the same area is also planned.
Completing State Route 509:
This construction work is part of WSDOT’s Puget Sound Gateway program which completes critical missing links in the state’s highway and freight network. SR 509 Completion Project builds three new miles of SR 509 and completes the unfinished SR 509 in south King County. The new four-lane highway will become an important north-south alternative to the congested I-5 corridor between Seattle and south King County.
The work on I-5 for Stage 1b of the SR 509 Completion Project will be complete in 2025; the entire SR 509 Completion Project will be complete in 2028.