ARLINGTON — Drivers on Interstate 5 at the Stillaguamish River should be prepared for left lane closures in each direction on both sides of the river beginning at 7 p.m. on Monday, June 16.

Contractor crews will close the northbound left lane from 7 p.m. until 2 p.m. the following day, and the southbound left lane from 7 p.m. to 10 a.m. The closures will occur Monday nights through Friday afternoons, so contractor crews working for the Washington State Department of Transportation can build crossover lanes in the interstate’s median.

The work is part of the project to replace the 81-year-old southbound I-5 Stillaguamish River bridge deck. In mid-July, southbound I-5 drivers will start to use the crossover lanes to access the northbound I-5 Stillaguamish River bridge. The northbound bridge will carry two lanes of I-5 in each direction. Concrete barriers along the bridge’s centerline will separate northbound and southbound traffic.

When the crossover lanes are complete, the southbound I-5 bridge will be closed for 120 days. The bridge deck has ruts, cracks and potholes. Some supporting steel also needs to be replaced. The southbound interstate bridge will reopen in the fall, and traffic will be restored to three lanes in each direction on the separate bridges.

The southbound I-5 Stillaguamish River bridge was built in 1933 to carry two lanes in each direction of US 99. It became part of I-5 when the interstate was built in the 1960s.

The northbound I-5 Stillaguamish River bridge opened in 1971.

Stay up-to-date about this work by visiting the project website at www.wsdot.wa.gov/projects/i5/stillaguamishbridgerehab, or sign up for Snohomish County email updates.