Next week, for the first time since the interstate system was constructed, there will be a way to get from I-29 to eastbound Broadway in Council Bluffs. It just comes at the expense of everything else, including the interstate itself.
According to an e-mail from the Iowa DOT, summarized and diagrammed at KETV, the northbound lanes of I-29 will be shut down between 9th Avenue and Avenue G. A frontage road will operate between those two places with a stoplight at Broadway. However, traffic is constrained to 35 mph, at least, officially and theoretically.
The easiest detour is probably taking old IA 192 — South Expressway, Broadway, and 16th Street — through Council Bluffs, since both ends intersect I-29. The official all-interstate detour will be much longer.
Mainline I-29 will not reopen in this area until summer 2023.