The Santa Ana Watershed (HUC 18070203) covers a land area of approximately 2,650 square miles in Southern California. It is characterized by a Mediterranean climate with hot and dry summers and mild winters. The watershed is fed by several tributaries, including the Santa Ana River, which is the largest river in Southern California. The region is prone to periodic droughts, and water management is a critical issue. The watershed is home to a diverse range of plant and animal species, including several endangered species. The region's snowpack is an important source of surface water, and changes in snowpack levels are closely monitored. The watershed features several reservoirs, including the Seven Oaks Dam and the Prado Dam, which provide water for both domestic and agricultural use. Recent trends show that the Santa Ana Watershed is experiencing increased temperatures and decreased precipitation, leading to a decline in snowpack and water availability. This has resulted in increased pressure on water resources and a need for sustainable water management practices.