The Watonwan watershed (HUC 07020010) covers approximately 1,022 square miles in southern Minnesota. The hydrology of the watershed is dominated by the Watonwan River, which flows for 121 miles through the region. The watershed experiences a continental climate with cold winters and warm summers, and it receives an average annual precipitation of 30 inches. In terms of surface water, there are several lakes and wetlands within the watershed, including Lake Hanska and St. James Lake. These water bodies provide important habitat for fish and wildlife. The reservoirs in the watershed, such as the Butterfield Lake Reservoir, are used for recreation and water storage. The snowpack in the watershed varies depending on the year, but on average, it receives around 40 inches of snow per year. This snowpack plays an important role in spring runoff and water availability throughout the year. There are no specific climatic facts or trends unique to the Watonwan watershed, but the region has experienced an increase in extreme precipitation events in recent years, which can lead to flooding and other water-related issues. Conservation efforts, such as the implementation of agricultural best management practices, are being undertaken to mitigate these impacts.