 Wyoming is a mostly arid state, but many of our communities are actually built in low-lying areas adjacent to rivers and streams, known as floodplains. Floodplains are a natural part of a river structure, and during high flows, such as spring runoff, rivers will exceed the normal channel capacity and flow across the surrounding land, the floodplain. People have built in and near floodplains throughout history. In the past, rivers were important corridors for transportation and trade. Because they receive periodic high flows that often carry lots of sediment, floodplains have excellent soils and agriculture thrives in floodplains. In order to accommodate human uses, floodplains are some of the most altered ecosystems in Wyoming. The natural processes that make floodplains valuable to humans, attractive to wildlife, and highly productive also make them hard to manage. Channelizing streams and draining wetlands in the floodplain make these areas easier to develop, but many of the benefits such as soil formation are lost without periodic flooding. People living in floodplains should understand that no matter how these areas have been altered, they will still flood at some point in the future. The Federal Emergency Management Agency, FEMA, provides maps and resources for people living in floodplains. Your local extension office has additional resources to help you understand floodplains and also to assist with disaster management during floods. For the University of Wyoming Extension, I'm Milton Geiger, Exploring the Nature of Wyoming.