Portion of I-90/SH-41 Interchange opens Friday in Post Falls

POST FALLS — Idaho Transportation Department has announced plans to open portions of the new Single Point Urban Interchange at Interstate 90 and Highway 41 on Friday morning.

The stretch of road has been under construction since 2022 and its opening marks a major milestone in the project, according to a press release.

The opening is expected to significantly change traffic through the area and cost $78 million to build, ITD said.

“We are asking drivers to please plan extra time and follow the signs and traffic control devices,” Project Manager Randy Durland said. “As drivers adjust to these changes, we appreciate everyone’s patience and extra attention in the work zone for the safety of both drivers and workers.”

For the first time, Highway 41 traffic will be shifted to the west to run underneath the new bridges and connect to the heart of the SPUI. 

Drivers will also be able to use the new westbound on-ramp and eastbound off-ramp.

Making this transition requires several large-scale closures throughout the interchange area overnight Thursday to set up cones, barriers, and signs that will safely route vehicles through the new traffic pattern.

By early Friday morning, motorists will be using parts of the new interchange.

Here’s what drivers can expect Thursday from 7 p.m. to 6 a.m.:

Highway 41 will be closed from 12th Avenue to Seltice Way.

The eastbound off-ramp from I-90 will be closed.

The westbound on-ramp to I-90 will be closed.

Mullan Avenue will be closed from Highway 41 east to October Glory Street. This closure may be in effect for several days, rather than just overnight.

In addition to the overnight closures, there will be temporary changes to side street and business access along Highway 41 between 12th Street and Neufeld Lane. 

The old highway is several feet higher than the new lanes being opened, so crews will need to lower the ground and add gravel to build temporary road connections.

Some of these access points will be closed only overnight, while others may be closed for a week or longer. Signs will be posted and detours in place to help drivers and customers get where they need to go.

Drivers will need to pay close attention to signs and lane markings as they get used to the new layout, especially those traveling south on Highway 41. 

After the traffic shift, drivers in the right lane south of Mullan Avenue will be required to merge onto the westbound I-90 on-ramp, where previously they had the option to either merge or continue south to Seltice Way.  

The I-90/Highway 41 Interchange upgrade is funded by Gov. Brad Little’s Leading Idaho program. 

For the remainder of the year, crews will focus on opening the westbound off-ramp and building the path for bicyclists and pedestrians along Highway 41. 

The full interchange is expected to open next year.

*This story has been updated to reflect the cost of the project.