SR 509 Completion Project – Summer 2023 Update
Pacific Northwest summers are unrivaled. It’s the time of the year when we get outside, bask in the sun’s warm rays, and check off some major construction milestones. This season, the SR 509 Completion Project team is continuing to perform major construction activities that will bring multi-modal improvements to the region.
Building tunnels without closing I-5
In May 2023, crews began constructing the new Veterans Drive extension under I-5. These two parallel tunnels, one for eastbound traffic and one for westbound traffic, will improve traffic flow between the Kent Valley and Puget Sound ports.
Atkinson is building tunnels with no drills, bores, or other subterranean munching machines while still keeping I-5 open to traffic. How? First, crews shifted the southbound I-5 lanes to the west and the northbound lanes slightly east to create enough space to excavate and build a central portion of the tunnel (shown below).
An overhead view of I-5, looking south, shows southbound lanes shifted to the west while crews excavate a portion of the future Veterans Drive tunnel.
Next, crews will fill in the excavated area and move the southbound lanes over the completed tunnel portion. Crews will continue shifting lanes of northbound and southbound I-5 to build segments of the tunnel until there are two continuous tunnels under I-5. Wow, engineering!
Atkinson places tunnel rings in the work site.
When the new I-5/SR 516 interchange is complete, Veterans Drive will extend west of Military Road South, passing under I-5 via a tunnel where it will meet southbound collector-distributor lanes leading to SR 516 and southbound I-5.
This rendering of the future Veterans Drive tunnel shows improved connections to, and across, I-5.
Construction safety is everybody’s responsibility
Reminder, the 50 mph speed reduction continues between milepost 150 near South 220th Street in Des Moines and milepost 148 near South 240th Street in Kent. The speed reduction will be in place until crews complete the central portion of the new Veterans Drive tunnel and move the I-5 traffic lanes back to their original configuration.
Would you like to guess how much longer it makes your trip if you reduce your speed by 10 mph through this section of I-5? Got your guess? Okay. The answer is 12 seconds.
Yep, that’s it. Seriously.
WSDOT implemented these speed reductions to keep construction crews and the traveling public safe. When traveling through the work zone, please be aware of your surroundings, obey speed limit signs, and ease up on the gas pedal.
New bridges take shape
Girders are reinforced concrete and steel beams that distribute the weight from a bridge deck to the bridge’s piers. In late June, crews began lifting, positioning, and securing massive girders for the new South 216th Street bridge over I-5 and the northbound I-5 to SR 509 flyover ramp. The 30 girders range from 65 to 200 feet in length and weigh as much as 252,100 pounds (126 tons). That’s some serious concrete!
Two cranes lift the first girder into place for the new South 216th Street bridge.
Now that the girders are in place, crews will begin building the bridge deck for the southern portion of the South 216th Street bridge and the northbound flyover ramp. Once complete, the new South 216th Street bridge will include a new eastbound turn lane, six-foot ADA-accessible sidewalks, and dedicated bike lanes that will reduce pedestrian and bicyclist exposure to traffic. The SR 509 to I-5 flyover ramp will connect to northbound SR 509.
This visualization shows where crews are placing girders for the SR 509 flyover ramp and a new South 216th Street bridge over I-5.
Staff feature: Joel Tex Widmer PE, CMIT, SR 509 Assistant Project Engineer, Puget Sound Gateway Program
What brought you to WSDOT?
I’ve always liked architecture and building in general. As a kid, I was obsessed with the “How it’s Made” TV series. Before coming to WSDOT, I worked on light rail expansion in Charlotte, North Carolina, and I got to work on a project in Florida that involved highways and wildlife overpasses. I also worked on the SR 520 Montlake Project when I moved to Washington in 2019. When the opportunity to work at WSDOT came up, I saw a chance to dive deeper into megaproject and be part of an agency that takes a lot of care in what they do. WSDOT doesn’t just care about drivers, but also Washington’s long-term goals. There’s a really strong goal to tie into other community amenities, like trails and natural areas, which doubles down on what I see as WSDOT’s commitment to the community.
What do you like most about your job?
It’s funny you asked that because I joined WSDOT a little over 100 days ago. Going on the 100-day mark, I love feeling like I’m contributing to improving the quality of life for people in Washington. Our project is tangible. I really liked attending community events like the Burien Strawberry Festival because I like seeing that other people are also excited about the project.
What do you wish people knew about your job?
WSDOT projects tie in more disciplines and mindsets than you can imagine. I get to collaborate with people who are experts in all sorts of areas like fisheries, wildlife, design, and even bird scientists. I get to learn more about all the things I loved growing up. There’s just a massive pool of expertise here. I also wish people knew that the WSDOT crews aren’t just strangers. They’re people in your community, like your neighbors, your friends, or your neighbors’ friends. People should try to behave safely while driving through construction zones because there are people in your community out there.
What are you up to when you aren’t working on the Puget Sound Gateway Program?
The quarantine era kicked off a plant collection obsession for me. I love bee rehabilitation and attracting butterflies to my garden. Our house was a gem in the rough when we found it in 2019, so we tore out all the ivy and other invasive species so now I can see hummingbirds from my window. I also love attending live events around town because there are bands of every genre here. |
