The Des Plaines watershed covers an area of approximately 1,800 square miles and is located in northeastern Illinois. The hydrology of the watershed is characterized by numerous small streams and rivers that eventually flow into the Des Plaines River. The area experiences a humid continental climate, with cold winters and warm summers. Snowpack varies from year to year, but the area typically receives an average of around 36 inches of snowfall per year. The surface water of the watershed is mostly used for drinking water, recreation, and industrial purposes. There are several reservoirs within the watershed, including the Chain O’Lakes and the Skokie Lagoons. Interesting climatic trends include an overall increase in temperature and a decrease in precipitation over the past several decades. These changes may have significant implications for the hydrology and ecology of the Des Plaines watershed in the future.