Start preparing now for weekend closures near the I-405/SR 167 interchange in August
UPDATE
Thursday, Aug. 23
The Aug. 25-26 weekend closure of southbound SR 167, along with all associated I-405 and SR 167 ramps, is canceled.
By Victoria Miller
It's the best of times in Seattle right now – sunny weather with more summer to come. However, it's also the season of abundant construction and weekend-long roadway closures.
In case you haven't noticed, construction on the
Interstate 405/State Route 167 Interchange Direct Connector Project is ramping up. Crews have been hard at work and are ahead of schedule, but in order to keep things on track, they need to conduct some major weekend roadway closures in mid and late August.
Before those closures can take place, though, we had a lot of prep work to undertake, including building a new ramp and looking after our project's aquatic neighbors.
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Crews poured concrete at two locations as part of ongoing construction
of the I-405/SR 167 Interchange Direct Connector ramp. |
The two species: fish and bugs
The new ramp to help commuters get through this area is just one of our efforts, we are also committed to helping another species travel through the area: fish.
Throughout many of our projects, the roads we are improving often cross creeks and streams where fish, including endangered and threatened species, live. In order to keep these streams flowing, we have installed large pipes called culverts under the roadways. We built most of the culverts before we fully understood fish habitat needs. At the time, we met all the culvert requirements, but in some areas, it's now challenging for fish to pass through the structures, and that's where our fish passage work comes in. We are now working across the state to address fish barriers by building and inserting new, larger culverts that are passable for fish.
For the Direct Connector project, crews have been installing a new, fish-friendly culvert in three phases south of the existing culvert in Rolling Hills Creek. The work began in fall 2017, and the first two phases occurred on land and in the wetlands next to the stream. The third and final stage of construction will happen in the stream when crews install the remaining pieces of the culvert underneath the roadway and realign the stream channel to flow into the new culvert.
Before the final culvert work can take place, crews need to move the fish away from this area so that they are not affected by the construction. This is what we call "fish exclusion."
In recent weeks, our project team has been relocating approximately 26,000 three-spined stickleback fish from a wetland adjacent to Rolling Hills Creek, to waters farther away from the construction site. The relocated fish still have a connection to their natural habitat and they will be able to move more freely once the project is complete.
Crews also found a surprise in the water -- giant water bugs, scientifically called
Lethocerus americanus and more commonly referred to as "toe biters" due to the painful bite they deliver if disturbed. The bugs are being relocated to the same waters as the fish.
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Giant water bugs – also called "toe biters" – were also relocated before in-water construction began. (Photo courtesy of Frank Vassen/Wikipedia) |
The two closures: Aug. 17-20 and Aug. 24-27
Speaking of bugs, we know that construction can really bug drivers and nearby communities, which is why we are letting you know a few weeks in advance that there will be two major weekend closures in August near the I-405/SR 167 interchange.
These closures are necessary for crews to complete the fish passage work we just described, as well as pavement reconstruction. Paving during an around-the-clock 54-hour weekend closure helps to ensure high quality outcomes when compared to work performed in the short work windows available during nightly closures adjacent to live traffic.
- Friday evening, Aug. 17, to the morning of Monday, Aug. 20 – Two lanes on northbound I-405 will be closed between SR 167 and Talbot Road South from 11 p.m. Friday until 4:30 a.m. Monday. Two lanes will remain open.
- Friday evening, Aug. 24, to the morning of Monday, Aug. 27 – All lanes of southbound SR 167 will be FULLY CLOSED between I-405 and South 180th Street from 8:30 p.m. Friday until 5 a.m. Monday. A signed detour will be in place.
For the latest construction closure information for these weekends, please visit the
I-405 Construction Updates webpage and the
King County Construction Updates webpage leading up to each weekend.
As with any major weekend closures, we encourage drivers to avoid the area and use alternate routes. Don't forget to also bookmark our
Seattle area traffic page, download the WSDOT app, and follow us on
Twitter for the very latest travel conditions. Remember these closures are still a month away and weather-dependent.
So if you're traveling to a Mariners game, a concert at White River Amphitheater or a weekend event in downtown Seattle, make sure to "know before you go" so you can still have the best of times and not the worst of times.