The East Fork Des Moines Watershed covers approximately 3,543 square miles in north-central Iowa. The hydrology of the watershed is dominated by agriculture, with over 80% of the land area being used for crops or pasture. The area experiences a typical Midwestern climate, with an average annual precipitation of 36 inches and an average annual temperature of 48°F. The watershed is home to several lakes, including Clear Lake, which is the largest natural lake in Iowa. The lake is a popular destination for recreational activities such as fishing and boating. The watershed also contains several reservoirs, including Saylorville Lake, which is managed by the U.S. Army Corps of Engineers. The reservoirs provide flood control, recreation, and water supply for the surrounding communities. The area has experienced an increase in precipitation over the past few decades, which has led to more frequent flooding events.