The Upper Leaf Watershed (HUC 03170004) covers an area of approximately 358 square kilometers in the northern part of the state of Wisconsin. The watershed is characterized by a temperate continental climate, with cold winters and mild summers. The hydrology of the region is dominated by snowmelt, which typically occurs in April and May. The snowpack in the region is typically deep and persistent, with an average snow depth of around 60 inches. The watershed contains a number of small lakes and streams, including the Leaf River, which flows eastward into Lake Michigan. Reservoir constituents in the region include a variety of fish species, including walleye, northern pike, and muskellunge. Interesting climatic facts include the fact that the region experiences frequent lake-effect snows during the winter months, with some areas receiving over 200 inches of snow per year. In recent years, there has been a trend towards milder winters and earlier snowmelt in the region due to climate change.