In all, 20 weekend closures are planned from now to April. The first closure is planned for the weekend of Jan. 4-7.
"There are so many construction projects in the Seattle area, we didn't want to add to the summer construction jam," said Russ East, assistant regional administrator with the state Department of Transportation.
"We planned ahead, worked with other agencies and determined that construction in January through April was the best way to get our work done and cause fewer headaches for drivers."
Between January and April in downtown Seattle, crews will:
Replace 31 expansion joints on ramps linking I-5, the West Seattle Bridge and Columbian Way and one joint on northbound I-5 just south of the ramps.
Grind and smooth out three lanes of southbound I-5 between 50th Street and Roanoke Street in the University District and add durable striping to both directions of I-5 between Northgate and Roanoke Street.
Use concrete and polystyrene to replace the creosote-soaked timber of the old Highway 99 bridge over Spokane Street just south of the West Seattle Bridge.
Replace bridge expansion joints and repave the ramp on northbound I-5 to Spokane Street (the West Seattle Bridge) and northbound and southbound I-5 off-ramps at Corson Avenue.
The total cost for these four projects is less than $30 million - not that expensive but very important from a safety perspective, transportation officials said. Left unfixed, cracking concrete and steel expansion joints that unexpectedly pop out can bring traffic through downtown Seattle to a stop.
I-5 is more than 50 years old and falling apart faster than state transportation crews can repair it, according to DOT officials. Each year, the Department of Transportation identifies areas most in need of repair and schedules critically important construction work.
"Waiting for an emergency to repair the backbone of our transportation system isn't safe or a good use of taxpayer dollars," East added.
This year, crews will focus on high-traffic areas, such as I-5 in downtown Seattle, the West Seattle Bridge interchange and the University District.