Reconstruction of Southwest Mixmaster (I-35-80-235)

planned

Work will soon get underway to rebuild the Southwest Mixmaster, where the interstates merge in West Des Moines. New flyover bridges will be constructed from southbound I-80/35 to eastbound I-235 and to westbound I-80. A new bridge for westbound I-235 will be constructed to allow for the realignment of I-235. Iowa DOT will also add a lane on eastbound I-235 between 50th Street and Valley West Drive as well as improvements to the ramps at 50th Street and Valley West Drive. Drivers won't see any impacts to their route until 2027. Contractors will be working outside of the travel lanes in 2026. Expect overnight work as crews resurface pavement, construct medians and add a new lane. Minimal disruptions are expected during winter 2026. Major disruption will come from the closure of the ramp from University Avenue to I-80 and I-235, with traffic shifted to reduce conflicts and improve safety.