The Upper Clark Fork Watershed (HUC 17010201) covers an area of 3,390 square miles in western Montana. It is a high-elevation watershed with rugged terrain and significant snowfall. The watershed is fed by several tributaries, including the Blackfoot, Deer Lodge, and Big Hole Rivers. The snowpack in the watershed is critical for maintaining water supply during the dry summer months. The Clark Fork River, the main river in the watershed, is heavily influenced by mining and milling activities that have resulted in contaminated sediments, metals, and other pollutants. These contaminants have impacted the quality of the surface water, soil, and vegetation in the watershed. The watershed is also home to several reservoirs, including the Anaconda Pintler and Georgetown Reservoirs. In recent years, the watershed has experienced warmer temperatures and earlier snowmelt due to climate change. This has led to changes in hydrology, with reduced snowpack and earlier peak runoff.