The forest watershed (HUC 09020308) covers an area of approximately 1,189 square miles and is located in northern California. The hydrology of the watershed is dominated by snowmelt, with the highest flows occurring in late spring and early summer. In terms of snowpack, the watershed receives an average of around 130 inches of snow per year, with the highest snowpack levels typically occurring in March. Surface water in the watershed is primarily sourced from the Trinity River, which is fed by a number of smaller tributaries. Reservoirs in the watershed provide important water storage for both agricultural and urban uses. Interesting climatic facts include the fact that the region experiences a Mediterranean climate, with hot, dry summers and mild, wet winters. Trends in the region indicate increasing temperatures and decreasing snowpack levels in recent decades as a result of climate change.