Two counties along the Missouri River are taking action to help protect communities from flooding both up and down-river using levee setbacks. Nemaha County, Nebraska and Atchison County, Missouri, are working with the Omaha District of the U.S. Army Corps of Engineers (USACE), Missouri Department of Natural Resources, Nebraska Department of Natural Resources, and Nebraska Public Power District to conduct a feasibility study assessing the flood reduction benefits from levee setbacks.
Major floods in both 2011 and 2019 highlighted the pressing need for improved flood resiliency in these areas, and flooding continues to be a concern during periods of heavy rainfall or snowmelt.
The Institute for Resilient Infrastructure Systems (IRIS) will use advanced flood modeling to inform the process, allowing the partners to weigh the benefits of placing the levee setbacks in different locations and at different scales.
Levee setbacks are a simple but effective way to prevent flooding. By realigning levees in strategic areas—namely those that are unpopulated and have room for the river to spread out and form a flood plain—and setting them further away from the river, managers can reduce flood hazards during heavy rainfall in communities both up and down the river. They also provide recreation area for locals and create habitat for wildlife.
In mid-January, community members were invited to join the partners to learn more about the study, share their experiences during the recent floods, and watch as the USACE and study sponsors held a signing ceremony to formalize the partnership.
“IRIS is honored to be able to inform this impactful work,” said Matt Chambers, IRIS Research Engineer and resident levee setback expert, who has led the University of Georgia’s involvement in the project.
“Our collaboration with Matt and other IRIS colleagues has gone a long way to inform these communities of the benefits and advantages of levee setbacks,” said Dave Crane, Environmental Resources Specialist with the USACE. “As flood risk management infrastructure ages and levees are subject to repetitive cycles of flood damage and repair, building a new levee further away from the river, with modern design standards, on more competent foundational material can be a sustainable approach to improving flood resiliency.”
To learn more about levee setback research at IRIS or to look for future updates on this work, visit our levee setback page.