The Santa Maria watershed (HUC 15030203) covers an area of approximately 707 square miles in central California. The hydrology of the watershed is characterized by a Mediterranean climate with hot, dry summers and cool, wet winters. The watershed receives its water from snowpack in the Sierra Nevada Mountains, as well as from surface water and groundwater sources. The Santa Maria Reservoir, located within the watershed, serves as a key water source for nearby agricultural and urban areas. The reservoir contains high levels of nutrients due to agricultural runoff, which can lead to harmful algal blooms. In recent years, the watershed has experienced drought conditions due to a decrease in snowpack and precipitation. Climate change is expected to exacerbate these trends, leading to further water scarcity in the region.