Earlier this week, IA 175 west of Mapleton closed for a bridge replacement. This complete shutdown over winter is unusual for Iowa construction.
US 20 in western Iowa was going to be detoured through Galva and Schaller over both the winters of 2016-17 and 2017-18, but the DOT backed off that plan on contractor’s preference.
IA 175 will be detoured between Mapleton and Castana on L32 and E34, and the state will “perform winter maintenance” on those roads this winter, the press release linked above says.