The Idaho Transportation Department will close Interstate 84 around the Karcher Interchange in Nampa starting this weekend to implement a traffic shift. This shift will allow crews to establish a safe work zone around the center pier of the bridge while maintaining the same number of lanes on I-84. Over the following weeks, crews will reinforce the interchange bridge to support the new westbound lane on Karcher Road (State Highway 55).
Here’s what to expect:
- Full closure of westbound I-84 on Sunday, 9 p.m. – 5 a.m.
- Full closure of eastbound I-84 on Monday, 9 p.m. – 5 a.m.
The Karcher Interchange project addresses the unprecedented growth in Canyon County by widening the interchange bridge, adding a free-running westbound right turn lane and an additional westbound lane through Caldwell Boulevard. Additional improvements will include:
- Upgrading signal equipment and adjusting timing at ramp intersections
- Adding a pedestrian flashing beacon at the I-84 eastbound on-ramp
- Adding a new sidewalk/bike path west of Caldwell Boulevard on the north side of Karcher Road (SH-55)
- Repaving Karcher Road (SH-55) from the westbound on-ramps to Middleton Road
This work is weather dependent and may be rescheduled if there is precipitation or temperatures drop too low. To learn more about the project or view detour maps, please visit the project website.