I-90 Construction Coeur d'Alene October 2026: Closures and Detours

"We recognize that this is a lot of change for drivers to keep track of," Zach Feist, a project manager for the Idaho Transportation Department, said in ITD's September 25 release on the I-90 widening between Post Falls and Coeur d'Alene. "Some of these dates will depend on the work that happens before them, so they may shift."

That second sentence explains the whole month. The ramp closures, the trail closure and the paving days scheduled for October are steps in one sequence, and each one clears the way for the next. They all lead to a single change targeted for around October 20, when both westbound lanes of I-90 move over to the south side of the interstate next to eastbound traffic. ITD expects that layout to stay in place for a full year. The closures will be over in a few weeks. If ITD's one-year estimate holds, the crossover is how the freeway will run until around this time next year.

Why the freeway has to move first

The project covers the five miles of I-90 from State Highway 41 to U.S. 95, which ITD calls the most heavily traveled and congested section of the corridor. Construction started in August 2025 and is scheduled to run four years, ending in 2029. When it's done, I-90 will have four lanes in each direction. The bridges over Huetter Road, Atlas Road and Prairie Trail will be replaced and widened. Every ramp at the Northwest Boulevard interchange will be lengthened, along with both U.S. 95 off-ramps, and nearby sections of Prairie Trail and the Centennial Trail will be realigned.

Crews can't rebuild the westbound lanes on the north side while people are still driving on them. So the crossover puts all four lanes of traffic on the south side, two each way, with narrow shoulders and concrete barriers between them. That frees up the north side for reconstruction. The October closures are the prep work for that move.

The October sequence, in order

From today, October 4, ITD's published schedule looks like this. Each step depends on the one before it:

1. Now through October 9. The eastbound I-90 on-ramp from Highway 41 in Post Falls closed at about 8 p.m. on Friday, October 2, and is scheduled to reopen October 9. The westbound on-ramp and both off-ramps at Highway 41 are still open.
2. Now through about October 12. The westbound on-ramp at Northwest Boulevard stays closed. It was supposed to reopen in late September, but crews found problems with how the newly rebuilt ramp connects to the interstate.
3. Starting October 12, for about a week. Prairie Trail closes beneath I-90 while crews start demolishing the westbound interstate bridge.
4. October 16 through 18, tentatively. Paving between U.S. 95 and Northwest Boulevard, with traffic down to one lane in each direction, day and night.
5. Around October 20. Both westbound lanes move to the south side for an expected full year.
6. After the shift, for up to two weeks. Huetter Road closes beneath I-90 while the old interstate bridges come down.
7. Shortly after the shift, for several weeks. Overnight closures of the westbound Highway 41 off-ramp.

The week of October 12 is the busiest stretch. If the schedule holds, the Northwest Boulevard ramp reopens the same day Prairie Trail closes, and the one-lane paving days start four days later on the stretch closest to downtown Coeur d'Alene. ITD says the timing depends on how the earlier work goes and suggests checking Idaho 511 before you head out.

The Northwest Boulevard extension follows the same logic

ITD had a choice when the ramp problem came up. It could make a shorter-term fix and reopen sooner, but that would mean closing the ramp again later. It chose to keep the existing closure in place and finish the work now. "We'd rather be upfront about the inconvenience now and get this work completed during the closure that is already in place," Feist said.

James Dorman, also a project manager on the widening, described the pace in similar terms in a September 30 report by The Coeur d'Alene Press on the Highway 41 ramp closure: "The widening project is moving quickly, and every step has a purpose." Taken together, the two quotes describe how the month is planned. A closure that runs long now is meant to prevent a second closure later.

Where ITD is sending traffic

There's a detail in the Northwest Boulevard guidance worth knowing. Although U.S. 95 via Appleway is the closest alternate, ITD "strongly encouraged" drivers who can use ramps farther east to do so, to spread traffic out and cut congestion. Westbound traffic entering at U.S. 95 still has its own lane and doesn't have to merge with traffic already on I-90.

The Huetter Road closure could also run into a separate city project. The City of Coeur d'Alene has said the Mill River Lift Station upgrade will bring intermittent closures on Grand Mill Road through mid-November, with one lane open in each direction, and the city named Huetter Road as an alternate. If the crossover happens on schedule, those two projects will overlap in late October and early November. Drivers who use both roads may need more than one backup route.

The year-long layout

Once the crossover is in, the corridor stays at two lanes in each direction, with narrow shoulders and concrete barriers between eastbound and westbound traffic. The westbound rest area will be closed to all traffic, commercial vehicles included. The eastbound rest area stays open.

ITD's project page lists what to expect for the rest of the project. Work usually happens Monday through Friday, both day and night, with some weekend work possible. Speed limits will change based on nearby work, posted on digital signs. ITD also asks through traffic on I-90 to keep left so vehicles have room to merge.

The roughly $200 million expansion is paid for mainly with Transportation Expansion and Congestion Mitigation funds, under Gov. Brad Little's Leading Idaho initiative. ITD says the TECM program lets it speed up projects that would otherwise take many years to fund and build.

The trails take part of the hit

For people who walk, run or ride instead of drive, October has its own set of closures. The Centennial Trail is still closed between Northwest Boulevard and Atlas Road because of the I-90 work and city waterline improvements. To the west, Kootenai County's Department of Parks and Waterways closed a separate two-mile stretch from Pleasantview Road in Post Falls east toward Spokane Street from September 23 to October 14, to replace worn-out asphalt. Parks and Waterways Director Nick Snyder put that project at $280,051. It's funded by the county, the cities of Post Falls and Coeur d'Alene, the North Idaho Centennial Trail Foundation and a state recreational grant. The county estimates about 800,000 people use the trail each year.

ITD hasn't posted a detour for the Prairie Trail closure that starts October 12. The project page only says the trail will be closed under I-90 for about a week. The trail work also points to the finished project. The realigned Prairie Trail and Centennial Trail sections are part of the plan, so some of these trail closures are rebuilding the paths, not just routing people around construction.

Questions about the corridor

Does the widening include the U.S. 95 interchange? No, that's a separate project. ITD's August 2025 release said it was in design, with construction possible as early as 2027.

What about the Highway 41 interchange? That's also a separate project. It's a single-point urban interchange rebuild that started in 2022 and is expected to finish in 2026.

How firm is October 20? ITD calls it a target. As of the September 30 announcements, the milestones were still October 12, October 16 to 18 and October 20, and ITD says the timing could change depending on construction progress. Sign up for ITD email and text alerts and check Idaho 511 for the latest.

If you're planning a sale, a purchase or a move in Coeur d'Alene over the next year, how a property reaches I-90, Huetter Road or the Prairie and Centennial trails during construction is part of the picture. Corcoran-Hall & Co. keeps track of how projects like this affect showings, moving days and daily routes across Kootenai County. Request a Private Consultation, and we'll go through the timing with you.