DES MOINES, Iowa — Drivers and truckers planning to cross Des Moines on Saturday night have a new schedule to work around. The Iowa Department of Transportation's Grimes Construction office said on Thursday, November 12, that the main overnight closure of northbound Interstate 35 / eastbound Interstate 80, between the Southwest Mixmaster and the Iowa 141 interchange, has been rescheduled: the full closure that was to run from 7 p.m. on Friday, November 13, will now run from 7 p.m. on Saturday, November 14, to 10 a.m. on Sunday, November 15, so crews can complete a shift of the travel lanes.
Source: Iowa Department of Transportation (via EIN News)
The change matters because the Friday-night closure was the centrepiece of this phase of the work. The two earlier overnight closures in the same series — on Wednesday, November 11, and Thursday, November 12, each from 10 p.m. to 4 a.m. — were for laying out pavement markings ahead of the shift. The longer Saturday-night closure is when crews reconfigure the northbound I-35 / eastbound I-80 lanes and move traffic onto the new alignment, according to the Iowa DOT.
The new schedule, in full
During the closure, drivers are directed onto the marked detour reported in the Iowa DOT's plan for this traffic shift: east on Interstate 235 to Valley West Drive (Exit 1B), then along NW 100th Street and NW Urbandale Drive to rejoin eastbound I-80 and northbound I-35. The detour runs on city streets with traffic signals, so the Iowa DOT's advice to expect a slower trip applies with extra force to trucks and anyone towing a trailer, for whom the signalised detour takes materially longer than the interstate run it replaces.
The Southwest Mixmaster is the interchange on the west side of the Des Moines metro where Interstates 35, 80 and 235 meet. I-35 and I-80 share lanes around the west and north of the city, which is why one closure hits two of the Midwest's main long-haul corridors at once: I-35 traffic between Kansas City and Minneapolis, and I-80 traffic between Omaha and Chicago. For Punjabi and other long-haul truckers who run those corridors — a large share of this site's US readers — a Saturday-night full closure on the shared stretch is a dispatch-planning problem, not just a local detour: loads timed for a Sunday-morning delivery window east or north of Des Moines need the extra detour time built in, or a Saturday departure moved earlier.
A second, parallel closure on westbound I-80
The rescheduled closure is not the only work at the interchange this week. In a separate notice, the Iowa DOT's Creston construction office said overnight closures of westbound I-80 between the Southwest Mixmaster and Grand Prairie Parkway (Exit 118) continue through the morning of Friday, November 13, weather permitting, from 8:30 p.m. to 5 a.m. each night. Those closures — extended because recent rains delayed grading and concrete paving work — also close the westbound on-ramps at the Southwest Mixmaster, 60th Street (Exit 122) and Jordan Creek Parkway (Exit 121), with a marked detour using University Avenue and Grand Prairie Parkway. This site covered the start of that westbound closure series on November 1; this week's notices are the later phases of the same interchange programme, and Saturday's traffic shift is the newest step in it.
The Iowa DOT reminds motorists to drive with caution, obey the posted speed limit and other signs in the work area, and be aware that traffic fines for moving violations are at least double in work zones. Schedules are weather-dependent — check Iowa 511 traveller information before setting out.
What happens next is the shift itself: after traffic is moved onto the reconfigured lanes on Sunday morning, drivers should expect a changed lane pattern through the Mixmaster–Iowa 141 stretch while the interchange programme continues. Questions about the northbound I-35 / eastbound I-80 project go to Kasi Province at the Iowa DOT's Grimes construction office (515-986-2863); questions about the westbound I-80 work go to Akhilesh Pal at the Creston construction office (641-782-4518), the department said.
Sources: Iowa Department of Transportation update, 'Overnight closures of northbound I-35/eastbound I-80 rescheduled for Nov. 14' (Grimes Construction office, Nov. 12, 2026, distributed via EIN News / EIN Presswire) and the Iowa DOT District 1 (Central) news listings; KJAN reporting of the Iowa DOT's original Nov. 11–13 closure plan and the westbound I-80 closure series.