The Bitterroot Watershed, located in western Montana, has a land area of approximately 4,500 square miles. Hydrologically, the watershed is characterized by a number of perennial streams and rivers, including the Bitterroot River, which flows for approximately 85 miles through the heart of the watershed. The watershed receives an average of 25 inches of precipitation each year, with snowpacks typically forming in the higher elevations during the winter months. Surface water quality is generally good, although there are some concerns about nutrient and sediment loading in certain areas. There are a number of reservoirs throughout the watershed, which are primarily used for flood control and irrigation purposes. Interesting climatic facts include that the Bitterroot Valley is one of the warmest and driest areas in Montana, with an average annual temperature of around 50 degrees Fahrenheit and an average annual precipitation of around 14 inches. In recent years, there has been a trend toward warmer temperatures and earlier snowmelt, which has implications for water availability and management in the region.