ONAWA, Iowa — July 31, 2026 — Northbound and southbound drivers on Interstate 29 at the Iowa 175 (Exit 112) should plan for nightly closures of all lanes of the roadway from 6 p.m. to midnight Monday, Aug. 10, through Friday, Aug. 14, weather permitting, according to the Iowa Department of Transportation's Sioux City construction office.

Crews need to close both northbound and southbound lanes of I-29 to set beams for the new Iowa 175 bridge over I-29. During the closures, traffic will be detoured around the work zone using the Iowa 175 exit and entrance ramps with flaggers to access I-29 in both directions

I-29 at Iowa 175 Onawa Detour Map

I-29 at Iowa 175 Onawa Detour Map

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. As in all work zones, drivers should stay alert, allow ample space between vehicles, and wear seat belts.

The latest traveler information is available anytime through our 511 system. Visit 511ia.org; call 511 (within Iowa) or 800-288-1047 (nationwide); stay connected with 511 on Facebook or X (find links at  https://iowadot.gov/travel-tools/iowa-511/511-social-media-sites); or download the free app to your mobile device. 

It’s easy to subscribe to Your 511 and sign up to receive email/text alerts. Visit https://new.511ia.org/#login to sign up. For instructions and help with this feature, visit https://www.511ia.org/help/section/how-to-create-and-manage-a-511-account.html.

###

For more information, contact Sarah Tracy, District 3 transportation planner, at 712-274-5831 or [email protected].