I-405 will see overnight closures starting Thursday, Sept. 3, with up to two southbound lanes closed from milepost 12 to Coal Creek Parkway Southeast until 5 a.m. Friday. Northbound I-405 will also have nightly lane closures from milepost 7 to 8. 5, starting Monday, Aug. 31, until Friday, Sept. 4.
I-90's eastbound off-ramp to Factoria Boulevard will close nightly from Monday, Aug. 31, through Friday, Sept. 4, with a detour in place. The I-5 near Alger/Lake Samish Road (exit 240) will have single-lane reductions nightly from 8 p.m. to 5 a.m. until Sept. 10 for fish passage construction.
State Route 20 will alternate traffic with flaggers from Swin Slough Bridge to Laconner Whitney Road/Bay View Road daily (except weekends) starting Aug. 21. SR 4 will have single-lane closures between 50th and 42nd Avenues weekdays from 7:30 a.m. to 5 p.m. until Sept. 11.