The Upper Rock watershed (HUC 07090001) is located in Maryland, covering an area of approximately 565 square miles. It is characterized by a humid subtropical climate with hot summers and mild winters. The hydrology of the watershed is primarily influenced by the Potomac River, which receives water from various streams that originate within the watershed. The area experiences an average snowfall of around 20 inches annually, with the snowpack contributing to the surface water supply. The watershed also contains several reservoirs, including the Little Seneca Reservoir and the Triadelphia Reservoir. The water in these reservoirs is primarily sourced from the upstream streams and is treated for consumption by the residents of the surrounding areas. The climatic trends in the region show an increase in temperature and precipitation over the years, which may have an impact on the hydrology of the watershed.