The Door-Kewaunee Watershed (HUC 04030102) covers an area of approximately 558 square miles in northeastern Wisconsin. The watershed is characterized by a mix of urban and agricultural land use, with some forested areas. The hydrology of the watershed is influenced by the Green Bay and Lake Michigan watersheds, which provide a significant source of surface water. The snowpack in the region can vary greatly from year to year, and can have a significant impact on the amount and timing of surface water runoff. The watershed is home to several reservoirs, including the Kewaunee River Reservoir and the Two Creeks Pond. The main constituents of these reservoirs are sediment and nutrients, particularly phosphorus. Interesting climatic facts and trends in the region include increasing average temperatures and more frequent extreme precipitation events.