The Rock watershed (HUC 10050015) covers a land area of approximately 1,120 square miles in north-central Montana. The hydrology of the watershed is heavily influenced by the Rocky Mountains, which receive significant snowfall during the winter months. This results in a specific snowpack that gradually melts during the spring and summer, providing a steady flow of surface water to the streams and rivers within the watershed. The surface water in the Rock watershed is primarily used for irrigation, but also supports a variety of aquatic species. The reservoirs within the watershed contain a mix of sediment, nutrients, and organic matter that can affect water quality. The climate in the Rock watershed is characterized by cold, snowy winters and warm, dry summers. In recent years, there has been a trend towards decreased snowpack and earlier snowmelt, which can have significant impacts on water availability and quality.