The Lower Sangamon watershed covers an area of approximately 1,802 square miles in central Illinois. The hydrology of the area is dominated by the Sangamon River, which flows through the center of the watershed. The watershed is relatively flat, with no significant elevation changes. Precipitation falls mostly as rain, and the snowpack is generally light and sporadic. Surface water in the Lower Sangamon watershed is primarily used for irrigation and recreation. There are several small reservoirs in the area, but they do not play a significant role in the hydrology of the watershed. The water quality in the watershed is generally good, but there are some concerns regarding nutrient runoff from agriculture. Interesting climatic facts include the fact that the area experiences a wide range of temperatures throughout the year, with hot, humid summers and cold, snowy winters. Climate trends in the area suggest that temperatures are increasing, and extreme weather events, such as heavy rainfall and flooding, are becoming more common.