The Middle Fork Willamette Watershed (HUC 17090001) encompasses an area of approximately 2,011 square miles in Oregon's Cascade Range. The watershed is characterized by the Middle Fork Willamette River and its tributaries, with an elevation range of 1,000 to 9,000 feet above sea level. The hydrology of the watershed is influenced by the region's mountainous topography, resulting in high stream gradients and rapid runoff from snowpack and precipitation events. Snowpack in the watershed is typically heaviest in February and March, with peak streamflow occurring in May and June. The watershed contains several reservoirs, which are used for water supply, hydroelectric power generation, and recreation. The climate of the watershed is characterized by warm, dry summers and cool, wet winters. In recent years, the region has experienced an increase in wildfires and drought conditions due to climate change.