Tuesday, July 8, 2025

Saddle Up: “Wild West Weekend” rides into Puget Sound with THREE big closures

Update: July 10, 2025
The work on southbound SR 167 in Kent has been postponed to a later date, and all references to that work have been removed from the blog. The other projects mentioned in this blog are still happening as originally scheduled.


Saddle up, Puget Sound – there's a highway showdown brewin' on all fronts. Dust is flyin', detours are comin' and a few of our rowdiest roads are fixin' to be wrangled.

This ain't your average construction weekend. It's a Wild (Pacific North)West showdown, and the only thing missin' is a tumbleweed.

Across Washington, we've got 117 projects under construction this season. But from July 11-14, all eyes are on a cluster of troublemakers right here in the central Sound: full closures on southbound I-405 in Kirkland, northbound I-405 in Renton, and southbound I-5 at the Convention Center in Seattle.

And just one week later, the most infamous outlaw of 'em all – Revive I-5 – rides into Seattle, shuttin' down northbound I-5 at the Ship Canal Bridge for the weekend of July 18-21 and kickin' off four weeks of lane reductions.

So, grab your map, chart an alternative course or saddle up a new horse (like KC Metro or Sound Transit) and keep an eye out, because the road crews are takin' the reins this weekend.

It’s a Wild West Weekend in central Puget Sound with three major closures wanted for disrupting travel.

Wild West Weekend's Most Wanted

WANTED: Southbound I-405 in Kirkland

ALIAS:  Buffalo BRT

Wanted for:  Occupying space meant for a transit-first interchange rebuild

What's goin' down:  As part of the NE 85th Street Interchange and inline BRT Station Project, crews will pave southbound I-405 as part of overall work to transform to better connected transit.

Closure details:  Southbound I-405 in Kirkland will be closed from Northeast 124th Street to Northeast 70th Place from 11 p.m. Friday, July 11 to 4 a.m. Monday, July 14

Ramp closures include:

  • Northeast 116th Street on-ramp to southbound I-405
  • Northeast 85th Street on-ramp to southbound I-405
  • Southbound I-405 off-ramp to Northeast 85th Street

View detour map

Project information:  I-405/Northeast 85th Street Interchange and Inline BRT Station Project | WSDOT

WANTED: Northbound I-405 in Renton

ALIAS:  The Express Toll Lane Bandit

Wanted for:  Occupying space needed for future express toll lanes

What's goin' down:  As part of the I-405 Renton to Bellevue Widening and Express Toll Lanes project, crews are shifting lanes and rebuilding the roadway to prepare for a future with more capacity, better access and new toll lane connections. During this closure, crews are installing upgraded drainage systems, replacing overhead sign structures and swapping out pavement panels.

Closure details:  Northbound I-405 in Renton will be closed between SR 169 (exit 4) and Sunset Boulevard NE (exit 5) from 11:59 p.m. Friday, July 11 to 4 a.m. Monday, July 14

Ramp closures include:

  • SR 169 on-ramp to northbound I-405
  • Northbound I-405 off-ramp to Sunset Boulevard Northeast (Exit 5)
  • The northbound SR 167 direct connector ramp to northbound I-405

View detour map

Project information:  I-405/Renton to Bellevue Widening and Express Toll Lanes Project

WANTED: Southbound I-5 at the Convention Center

ALIAS:  The High Pressure Kid

Wanted for:  Givin' fire systems under the Convention Center a midnight wakeup call

What's goin' down:  WSDOT maintenance crews are ridin' in overnight to test the fire suppression system beneath Seattle's Convention Center. It's a quick mission to keep our tunnel infrastructure safe and ready.

Closure details:  Southbound I-5 in Seattle will be closed from the Stewart Street off-ramp to the Spring Street on-ramp from 11 p.m. Friday, July 11, to 6 a.m. Saturday, July 12.

Ramp closures include: 

  • Eastbound Mercer Street on-ramp
  • Yale Avenue/Howell Street on-ramp
  • Union Street off-ramp
  • James Street off-ramp

Detour:  The Express Lanes will run southbound during this closure.

ACCOMPLISES:

  • Westbound I-90 off-ramp to SB Rainier Ave S: Closed 9 a.m. Friday, July 11, to 5 a.m. Monday, July 14, for SDOT pedestrian safety upgrades.
  • Northbound I-5 off-ramp to NE 130th St: Closed starting 10 p.m. Friday, July 11, until late July for Sound Transit Lynnwood Link construction
  • Eastbound NE 130th Street over I-5: Closed until Aug. 25

Highway Showdown Survival Guide

Even if it isn't your first rodeo, plan ahead for a full-scale, multi-corridor roundup across the region with closures and detours. Whether you're ridin' solo or hauling a whole wagon train, you'll want to be ready before you head out. Here's how to stay one step ahead:

  • Scout the terrain: Check WSDOT's real-time traffic map, mobile app, or social media before you ride out. A smart traveler knows what's ahead.
  • Pick your moment: Avoid the rush. Leave early, return late, and give yourself time for the long way 'round.
  • Know your back-up route: Review signed detours and alternate trails before you saddle up.
  • Follow the front line: Flaggers, signage, and law enforcement are out there helping keep order and guiding the herd. Tip your hat and follow their lead.
  • Switch saddles if needed: Transit, carpools, and HOV lanes might be the quicker horse for this ride.

Til We Ride Again, Pardner

Closures come and go, but the job's bigger than one weekend. Next week, we ride again. Northbound I-5 at the Ship Canal Bridge will fully close from July 18-21 and then reopen with four weeks of lane reductions while we work to preserve this valuable corridor. We're laying the groundwork for stronger roads and smoother rides downline.

Out here on the asphalt frontier, it's not the fastest rider who gets through, it's the one who knows the trail, reads the signs and plans their route.

Monday, July 7, 2025

Turn and face the change: Big changes coming to the South 188th Street/SR 509 interchange in south King County

We may have rounded the corner to summer and can finally (hopefully?) put away our raincoats and puffy jackets until fall. But there are bigger changes than the seasons coming to the South 188th Street/State Route 509 interchange as part of the SR 509 Completion Project in south King County.

Upcoming changes to SR 509 Interchange

Scheduled to begin Monday, July 7, crews will change the SR 509 ramps to and from eastbound South 188th Street/Des Moines Memorial Drive South and install a new traffic signal. Drivers will use the new traffic signal to:

  • Enter northbound SR 509 from both directions of South 188th Street/Des Moines Memorial Drive South.
  • Exit southbound SR 509 to eastbound South 188th Street/Des Moines Memorial Drive South.

People driving from southbound SR 509 to westbound South 188th Street/Des Moines Memorial Drive South will continue to use the existing off-ramp. This change will be in place for the next two years.

A traffic map showing a temporary detour near SR 509 and South 188th Street, effective from May 2025 to spring 2027. The on- and off-ramps between eastbound South 188th Street and SR 509 will be closed. Southbound SR 509 drivers will use a widened ramp to access eastbound South 188th Street. Eastbound South 188th Street traffic will turn left onto the widened ramp to go northbound on SR 509. There is no change in traffic flow between SR 509 and South 188th Street in certain areas. A new traffic signal will be added at the intersection of the widened ramp and South 188th Street.
Starting July 7, crews will change the SR 509 ramps to and from eastbound South 188th Street/Des Moines Memorial Drive South. 

Changes necessary for safety and efficiency

These changes to the SR 509 and South 188th Street/Des Moines Memorial Drive interchange are a key step toward building the new SR 509 Expressway between South 188th Street and 24th Avenue South. This work is important to make the construction area safer and more efficient for our crews. Once this section of the expressway is complete, we’ll begin major upgrades to the interchange, including new roundabouts and a multi-use path that will link directly to King County’s Lake to Sound Trail.

If you live near, work near, or travel through this area, expect noise and dust typically associated with road construction. Trying to reach local businesses? Don’t worry, we’ll make sure you can still get there.

Short-term inconvenience for long-term benefits

We know traffic changes are a hassle, but we promise the short-term inconvenience will pay off in big ways down the road (pun intended). Once complete, the improvements to the South 188th Street interchange and the new SR 509 Expressway will reduce congestion, streamline traffic flow, and boost safety in the area, making it easier for everyone to get around.

This is all part of the larger SR 509 Completion Project, which:

  • builds a new four-lane expressway between Interstate 5 and SR 509's current end near Sea-Tac Airport
  • builds new I-5 ramps
  • improves I-5 interchanges in south King County
  • constructs new bridges

When the entire SR 509 Completion Project is done, it will create an important north-south alternative to the congested I-5 corridor between Seattle and south King County. The future is bright!

New interchange improves access

When all is said and done, the new SR 509/South 188th Street interchange will let people travel in all directions, improving access for everyone—whether you’re heading north, south, east or west. The design will include roundabouts, which are safer and more efficient than traditional intersections. Plus, for those heading south on SR 509, the South 188th Street interchange will be the last exit before the expressway’s tolled section.

A rendering of the future SR 509 and South 188th Street interchange showing roundabouts on both sides of an overpass at South 188th Street. Labels indicate directions toward Seattle and southbound I-5. Des Moines Memorial Drive and the Lake to Sound Trail are shown to the northwest, while a new shared-use path and South 188th Street run through the lower right of the image. A label marks the "Last exit before toll" near the top. The image includes a large red north arrow pointing up and to the right.
When the SR 509/South 188th interchange work is completed, people will be able to travel in all directions with improved access whether you drive, walk, ride or roll through the area.

Why roundabouts?

Because they work—and they work well. Our interchanges are designed to be safer for all road users, including drivers, pedestrians, and cyclists. Roundabouts help slow down traffic, provide safer crosswalks, and reduce the chances of dangerous collisions. They also keep traffic moving smoothly and efficiently, even as volumes increase.

For this project, we ran traffic studies and simulations to determine the safest and most effective design. The roundabouts came out on top, outshining other options, especially when we factored in large vehicles like trucks and buses, as well as non-motorized users.

Roundabouts are already working wonders at over 100 locations across Washington State. We’ll continue share information roundabout safety, so everyone feels confident navigating them once construction is complete.

Have questions or want more information?

We know that change brings questions, and we’re here for them! Send us an email at sr509construction@wsdot.wa.gov or give our 24/7 construction hotline a call at 206-225-0674.

Want to stay updated? Sign up for our project listserv to get the latest news and updates straight to your inbox.

Thanks for your patience as we work to make this important project a reality. We’re excited for the positive changes that lie ahead!

Wednesday, July 2, 2025

Streaming soon under US 101: Season 3 of major fish passage construction on the Olympic Peninsula

By Angela Cochran

It may not be the show you’ve been waiting for the past several years (looking at you, Stranger Things!), but it’s sure to be the talk of the town for summer travelers on the Olympic Peninsula.

With eight new episodes – uh, we mean work zones – it’s lights, camera, action – ok, well it’s just lights. Red, yellow and green ones. Traffic lights, to be specific. But don’t worry! They are all temporary.

Two traffic signals with red lights sit on an orange trailer extended over the closed side of the highway with orange barrels around it. Large trees line the shaded highway.
You’ll see a lot of these guys if you’re traveling US 101 along the coast this summer.

If your summer plans include taking the “loop” (US 101 on the Olympic Peninsula), you’ll want to include some extra travel time. But we’ll keep you moving through the work zones.

This is the third season of our “Coastal 29” project. The work removes barriers to fish at 29 locations under US 101 and State Route 109.

Map of the west coast of Washington showing multicolored dots indicating locations of fish passage sites on US 101 and SR 109.
All of the fish passage locations that are part of the Coastal 29 project.

We reached the halfway point for the project last fall after completing work at five locations under SR 109 near Ocean Shores and four locations under US 101 south of Forks. This summer, we’re getting US 101 ready for its closeup.

Bonus episode

In addition to the fish passage sites, we have a ninth location where US 101 is reduced to one lane of alternating traffic. This is due to erosion along the highway near Kalaloch. In the next several weeks, our contractor will work to repair the hillside and reopen both lanes.

Plot summary

The temporary changes will remain in place at the eight fish passage work zones through the end of the year. The changes include a temporary bypass road. Most of the locations already have traffic on bypass roads. These locations all have one-way alternating traffic around the clock. The bypass roads will open at the remaining locations within the next couple of weeks.

Aerial photo showing US 101 with a temporary roadway around a large hole with a new metal structure.
Aerial image of a bypass road with a temporary bridge. 

Once traffic is shifted onto the bypass road at each location, crews will start digging up the highway and relocating aquatic life in the stream. Before stream work begins, we temporarily divert the stream. This happens during a time when fish are less active in the stream. We call this the “fish window”. This window varies by location. For these streams, it starts in July.

Up next

After the Independence Day holiday, we will block off the project area with fencing and move fish and other species up or down stream of the project. We also document the number and types of species found in the stream during this time. A pipe is then used to divert the stream around the project area, which gives crews the room they need to rebuild the stream bed. Once that work is complete, tree trunks and native plants are added for shelter and nutrients. In addition to the stream work, we build the new structure.

Workers stand in a stream surrounded by orange fencing to catch and move fish out of the project area.
Fish passage work includes relocating aquatic life before working in the stream.

Main character arc

One of the projects just hit a big milestone. We placed girders, or large support beams, on the new bridge over May Creek. This project is located at the Jefferson/Clallam county line south of Forks. Girders act as the backbone of a bridge. They are placed on top of the piers and support the driving surface. The new May Creek bridge has five girders that are each 175 feet long – the size of the Seattle Ferris Wheel!


Now that the girders are in place, we are working on the bridge deck. The contractor expects to finish most of the bridge work and open it by the end of this year. If this happens, they will pause work for winter and perform stream work when the fish window opens in summer 2026. We expect to complete the whole project in fall 2026.

Next season on Coastal 29

All bingeworthy series come to an end. By the end of this year, we will have removed barriers to fish at 22 locations under US 101 and SR 109. It’s been blockbuster work since 2023.

That means our construction series finale will be a little shorter. We’ll only have seven culverts left to replace along the coast in 2026 and 2027. Crews will finish work at the two sites under US 101 near Forks next summer. We will also replace culverts under SR 109 at five locations to complete this massive endeavor.

As always, you can tune in for live traffic information on our app and statewide travel map.

It’s rewarding work removing barriers to fish. You could call it a rerun (but, you know, with fish).

Tuesday, July 1, 2025

Two local roads in SeaTac close to make way for the new SR 509 Expressway

South 194th Street connection to Des Moines Memorial Drive South will close permanently on July 7. South 192nd Street is scheduled to close for nine months also on July 7

The long-awaited State Route 509 Expressway in south King County is taking shape. Before travelers can move without stopping between South 188th Street and I-5, our construction crews have a lot of work ahead of them at South 192nd and South 194th streets near Des Moines Memorial Drive in SeaTac.

South 194th Street is closing for good

First up: On July 7 crews will permanently close the South 194th Street connection to Des Moines Memorial Drive South. This is because the new expressway is going to be built right where the current intersection is located.

Building the new South 192nd Street bridge

Shortly after South 194th Street is closed, crews will shut down a portion of South 192nd Street for nine months while they build one of five new bridges for the expressway. It’ll be closed just west of Des Moines Memorial Drive.

Right now, South 192nd Street is just a road, but it will become a bridge. The new SR 509 Expressway will go under South 192nd Street. To build the expressway, crews need to dig out the road and transform it into a bridge. South 192nd Street, between Des Moines Memorial Drive South and Eighth Avenue South, will be closed for about nine months starting July 7.

Rendering showing a semi-truck on SR 509, approaching the 192nd Street bridge
The new South 192nd Street bridge will better serve the needs of the community with wide, ADA-accessible sidewalks.

The new South 192nd Street bridge will better serve the needs of the community with wide, ADA-accessible sidewalks.

Originally, crews planned to build the new bridge before permanently closing the South 194th Street connection to Des Moines Memorial Drive. But closing both at the same time results in:

  • Safer detour routes with fewer tricky left turns.
  • Keeping Des Moines Memorial Drive South open more often.
  • Less dust and dirt from construction vehicles.
  • Trucks having the ability to travel during the day instead of at night.
Rendering of the SR 509/Des Moines Memorial Drive crossing

Getting around during construction

While South 192nd Street is closed:

  • Cars will be detoured to South 188th Street or South 200th Street using Eighth Avenue South and Des Moines Memorial Drive South.
  • Large trucks should use First Avenue South to avoid tight turns at Eighth Avenue South.
Map of the SR 194 - SR 192 detour route

If you live or work nearby:

  • Driveway access on South 192nd Street will be maintained.
  • Expect noise, dust, and vibration during regular work hours (weekdays, 7 a.m. to 5 p.m.)
  • Some night work may be necessary (weekdays, 8 p.m. to 6 a.m.).

If you commute through the area:

  • Use extra caution through the work area and detour route and expect delays.

If you use the Lake to Sound Trail:

  • Expect closures and detours during bridge. construction. Visit our project webpage for updates.

The new South 192nd Street bridge over the future SR 509 Expressway is scheduled to open in early 2026.

Project background

The SR 509 Completion Project in King County is part of the Puget Sound Gateway Program, which also includes the SR 167 Completion Project in Pierce County. Together, these projects complete two of the Puget Sound region’s most critical freight corridors and improve access to I-5, the ports of Tacoma and Seattle, and Seattle-Tacoma International Airport. The SR 509 Completion Project builds a new four-lane expressway between I-5 and SR 509's current end near Sea-Tac Airport, builds new I-5 ramps, improves I-5 interchanges in south King County, and constructs new bridges. When complete, the project will create an important north-south alternative to the congested I-5 corridor between Seattle and south King County.

Keep in touch

The best way to stay up to date on the SR 509 completion project is to sign up for our listserv. Questions? Send us an email at sr509construction@wsdot.wa.gov or give our 24/7 construction hotline a call at 206-225-0674.