Iowa City, Iowa was among the hardest hit communities from the 2008 Iowa River floods. Extensive flooding along the riverfront, including inundation of a major wastewater treatment plant located along the river, prompted the community to take action. Rather than restoring the vulnerable North Wastewater Treatment Plant, Iowa City decided to decommission the plant and expand service at a facility located outside the floodplain. The plant had an average daily treatment of 9.7 million gallons with a design capacity of 24.2 million gallons per day. Although it did not quantify future climate risks explicitly, Iowa City consciously sought means to reduce the vulnerability of its wastewater services to future extreme storm events, which are projected to increase in the Midwest according to the 2014 National Climate Assessment.
The process to decommission, demolish and expand wastewater treatment services elsewhere is projected to cost $63 million. By decommissioning the vulnerable wastewater treatment plant and converting the surrounding area into a public greenspace, the city has adapted to reduce the threat and impact of future extreme storm events.