ITD changes I-90 traffic through Coeur d'Alene for widening work

Westbound Interstate 90 through Coeur d’Alene narrowed again June 19 as the Idaho Transportation Department closed the Northwest Boulevard off-ramp and shifted drivers onto 4th Street and Appleway Avenue. At the same time, westbound through traffic was reduced to one lane between U.S. Highway 95 and just west of the Northwest Boulevard on-ramp, a change ITD said was designed to make merging safer while crews work near the interchange.

The adjustment hits one of North Idaho’s most congested stretches of freeway. ITD said the widening project covers the five miles from State Highway 41 in Post Falls to U.S. 95 in Coeur d’Alene, the first construction package moved forward from the I-90 Corridor Study. Construction began in August 2025 and is scheduled to continue through 2029, with the corridor ultimately expanded to four lanes in each direction.

ITD says the reason is simple: traffic is coming. The agency projects corridor volumes will double by 2045, which it says will require more lanes and interchange changes to cut congestion and reduce crashes. The current pattern stays in place until further notice, while crews keep building retaining walls near Northwest Boulevard.

The change also shifts pressure onto nearby access points that local drivers and businesses already rely on. ITD has said the 4th Street Interchange is being used to help keep backups from spilling onto I-90 at the U.S. 95 off-ramp, and the agency has repeatedly pointed to the U.S. 95 and Northwest Boulevard interchanges as two of the busiest in the corridor. Earlier phases included week-long, 24-hour ramp closures and detours as crews demolished and rebuilt ramps to meet modern engineering standards and future growth needs.

ITD has urged drivers to use alternate access points such as 4th Street, 15th Street, Sherman Avenue or SH-41 when possible, and to keep left on through traffic to leave space for merges. The warning matters well beyond commuters, since ITD also said the detours were meant to reduce congestion on Northwest Boulevard and Ironwood Drive, routes used by emergency vehicles and ambulances heading to the hospital.

The construction is affecting trails as well. ITD said sections of the Centennial Trail have been closed for I-90 widening and city waterline work, with pedestrian and bicycle detours set through Riverstone Drive and Seltice Way. The June 19 notice also said the Prairie Trail under I-90 would close for up to a month, with detours via Kathleen Avenue, Atlas Road and Seltice Way. Trail users were told to slow down, stay alert and follow the signs through the work zone.

The bigger corridor plan still stretches nearly 16 miles from the Washington state line to SH-41, but the western section remains on hold until more funding is identified. For now, the lane shift at Northwest Boulevard is the clearest sign yet that the long rebuild of I-90 through Kootenai County is moving from planning into daily inconvenience.