Supply and Demand Assessment (SDA) – San Gregorio Creek Watershed

The San Gregorio Creek Watershed is located within San Mateo County, extending from the Santa Cruz Mountains to the Pacific Ocean. The watershed area is approximately 51 square miles, with an elevation ranging from sea level to about 2,700 feet. Please note that the modeling domain includes San Gregorio Creek and some neighboring watersheds. This watershed has a Mediterranean climate and its primary land cover is forest and shrubland. The watershed has several dams and reservoirs, and much of the watershed is used for rangeland and other agricultural activities. Timber harvesting has historically played a substantial role in the watershed’s development as well. The San Gregorio Creek Watershed is listed under Section 303(d) of the Clean Water Act for excessive sedimentation. The watershed provides habitat for several threatened species, such as steelhead trout and coho salmon, and increases in erosion and sedimentation have impacted their habitats.