Monday, May 22, 2017

Weekend-long lane reductions scheduled for northbound I-5 in SeaTac, Tukwila

By Tom Pearce

Our work to #ReviveI5 in South King County is about to ramp up! Since mid-April, crews on northbound I-5 between Kent and Tukwila have been replacing broken concrete panels, grinding the concrete to eliminate ruts, repairing concrete and much more - all while many of us are sleeping.

But some work requires more time than an overnight window can provide. Starting Friday, June 2, we'll begin the first of the project's 10 weekend-long lane reductions. We have eight weekends planned for 2017 and two in 2018. If the weather holds up, here's the six we've schedule so far:
  • June 2-5, 16-19, 23-26
  • June 30-July 3
  • July 7-10, 14-17

The cracker slowly rolls down southbound I-5, breaking the 50-year-old concrete panels.

During the six weekends already scheduled, our contractor will do crack-and-seat paving between State Route 516 in SeaTac and South 170th Street in Tukwila. For each of these weekends:
  • Crews will start reducing lanes at 8 p.m. Friday
  • By 10 p.m. Friday, northbound I-5 will be down to two lanes.
  • Between 11 p.m. and 4 a.m. on Friday and Sunday nights, northbound I-5 may be reduced to one lane.
  • By 5 a.m. Monday all lanes will reopen.
Why limit lanes on the weekend?
The simple answer is, there are some things we can't finish during an overnight lane closure. When we do crack-and-seat work, we have to remove a football-field length of concrete panels across two or three lanes at each end of the work zone and replace them with asphalt. You can't dig up that much concrete, then repave with asphalt in a single night.
During southbound work in 2016, crews use a roller to smooth out a section where new asphalt will be paved.

Besides replacing the concrete with asphalt, we have to use a cracking machine with a 12,000-pound blade to break a couple of miles of concrete. Crews then need to compress the pavement with a 35,000-pound roller. Next, we have to put asphalt over the top of that. We did this last year on southbound I-5 in the same area and it took all weekend to finish.

We're still scheduling the last two weekends in 2017. Those will probably be in late summer or fall, when we'll replace four expansion joints on the Duwamish River Bridge.

In the first half of 2018 we'll have two more weekends with northbound I-5 reduced to two lanes as we replace expansion joints on the Interurban Avenue overpass.
It takes a weekend to chip out old expansion joints, place new ones and pour the concrete.

We understand the inconvenience of all this work, but I-5 is more than 50 years old. If we want it to continue serving our families and businesses another 50 years, it needs major preservation work. The weekend-long lane closures allow us to complete parts of the project that need more time.

You can stay updated on work and traffic by checking our construction update page, following our Twitter account, checking our traffic map and downloading our mobile app.

Thanks for your patience!