POLK COUNTY, Iowa — Crews are working on phase one of the East Mixmaster reconstruction. They’re redoing ramps connecting I-80, I-35, and I-235 in Polk County between Des Moines and Ankeny.

In this phase, the ramps connecting I-80/35 with I-235 north and I-80 west with I-235 north are being redone. Construction on phase one is expected to last until June 2024. For cars going from I-80/35 to I-235 north, crews will move the interchange entrance from the left to the right side of the road.

Frank Leong, Iowa DOT Grimes Resident Construction Engineer, is overseeing the project. He said phase one is expected to cost $55 million.

He added the project will modernize the interchange by making the ramps longer and straighter. That will allow cars to move through safely at higher speeds, which should increase capacity.

“The interstate system has been around quite a long time,” Leong said. “As with anything we do, we get better as time goes on. So these roads were built as early as the 1950s all the way through the 1980s and standards have changed. So we are upgrading it to what we say ‘modern standards’ to what folks can increase speed and get through the interchange safer.”

He said work right now shouldn’t impact traffic very much. There may be some intermittent road closures at night to move equipment. Crews will start closing some nearby streets in spring 2023 as work continues. Drivers likely won’t see major impacts until fall 2023 when crews build the bridge connecting I-80/35 and I-235 north. That will require the DOT to close the interstate some weekends for construction.

Leong said future phases are currently in design. They have not yet been scheduled.