The Upper Pee Dee Watershed (HUC 03040104) covers a land area of approximately 2,479 square miles in South Carolina. The watershed is characterized by a humid subtropical climate with warm summers and mild winters. The hydrology of the watershed is dominated by the Pee Dee River, which is the primary source of surface water. The watershed experiences occasional snowfall during winter months, but snowpack is generally not a significant contributor to the hydrology of the region. The primary reservoir within the watershed is Lake Robinson, which is used for hydroelectric power generation, recreation, and water supply. The reservoir is fed by several smaller tributaries and also receives water from the Pee Dee River. Interesting climatic trends in the region include increasing average temperatures and more frequent extreme weather events, such as hurricanes and flooding.