The goal of flood mitigation is to reduce the risk of flooding and reduce the consequences when it happens. Flood mitigation happens at the community level as well as the individual homeowner level. Planning and zoning, floodplain management, keeping development out of the most risky areas, and public outreach are examples of community-level mitigation actions. Purchasing flood insurance, elevating your home, or relocating out of the floodplain are examples of homeowner-level mitigation activities.
Structural Flood Mitigation
Flood mitigation projects are classified in two categories: "structural" and "nonstructural." Structural projects involve levees, dams, floodwalls, jetties, and many more. Structural projects aim to move the river away from people. The US Army Corps of Engineers is the federal agency charged with construction and maintenance of major structural flood mitigation projects. In Nebraska, many Natural Resources Districts also have structural projects. One example of a system of structural projects is the set of lakes in Omaha that include Wehrspann, Zorinsky, Cunningham, Walnut Creek, and Standing Bear Lakes. These lakes provide protection from floods by storing floodwater behind dams and releasing the water in a controlled manner, so the streams beneath the dams rarely have an extremely high flow. The lakes provide other benefits like recreation and wildlife habitat. Levees are other examples of flood control projects that keep water away from people. The community of Waterloo in western Douglas County is protected entirely by a levee to keep floodwaters from the Elkhorn and Platte Rivers away.
Nonstructural Flood Mitigation
Nonstructural projects are designed to change the way people interact with floodplains and flood risk. Nonstructural projects aim to move people away from the river and might include keeping floodplains as open space, acquiring or elevating the most at-risk structures, or broad community planning for floodplain management. The Federal Emergency Management Agency has many programs, in parntership with the State of Nebraska, to provide funding for nonstructural flood mitigation projects. Learn more about grants available for flood mitigation in Nebraska here.
A good example of a major nonstructural mitigation project is the city of Beatrice's project to buy out over a dozen properties located in the most flood-prone areas along the Big Blue River. These properties had received major flood damage in the 1993 flooding season. The City of Beatrice worked with NDNR and FEMA to purchase homes at market value near the river and then demolish the structures, leaving open space in the floodplain. The homeowners found new places of residence in lower-risk areas and with the houses removed from the floodplain, there will be no flood damage on those properties in the future. Nonstructural flood mitigation attemps to restore floodplains to their natural state and allow communities to thrive while becoming more resilient to risk posed by streams.
Flood mitigation actions fit into a broad set of "all-hazards mitigation" activities, which protect people and property from all types of hazards including fire, winter weather, tornadoes, floods, and man-made hazards. FEMA requires communities, in order to be eligible for some financial assistance, across the country to prepare "all-hazards mitigation plans" (HMPs) that address community hazard risk and various mitigation alternatives that can be put in place. Many of these plans in Nebraska are organized by Natural Resources District area, but some plans are available at the county or multi-county level. Communities prepare these HMPs to be more informed about the range of hazards that could affect them and develop solutions that could reduce the future risk from the identified hazards.