San Francisquito Watershed
San Francisquito Creek and its tributaries cover a 47.5 square miles area on the northwestern Santa Clara and southeastern San Mateo counties. The watershed is bounded to the southwest by the Santa Cruz Mountains. San Francisquito Creek itself flows 12.5 miles from Searsville Dam to the Lower South San Francisco Bay. It defines the border between San Mateo and Santa Clara Counties. San Francisquito Creek traverses through unincorporated County, Stanford University land, the towns of Portola Valley and Woodside, as well as the cities of Menlo Park, Palo Alto, East Palo Alto, and Stanford University.
The upper watershed is comprised of undeveloped forest and grazing lands and low-density residential neighborhoods. On the valley floor, higher-density residential development exists along with commercial development focused on major surface streets. Stanford University occupies a large portion of the valley portion of the watershed as does the downtown portion of the City of Palo Alto.
The watershed is famous for its reproducing steelhead population. Besides steelhead, native fish found in the watershed are the California roach, Sacramento sucker, hitch, speckled dace, threespined stickleback, and prickly sculpin. Seven nonnative species also exist in the watershed. The threatened California red-legged frog lives along the Creek.
- Watershed area: 42.8 square miles
- Number of tributary creeks: 25
- Miles of natural creek bed: 90.6
- Miles of Engineered Channel: 4.8
- Local cities: Santa Clara County, San Mateo County, Woodside, Portola Valley, Palo Alto, Stanford University, Menlo Park, East Palo Alto.
- Percent area by land use:
- Residential 29.6%
- Industrial/Commercial 5.2%
- Forest 44.7%
- Rangeland 15.0%
- Other 5.5%
- Percent Impervious Area: 20.8%
- Miles of Underground Culvert or Stormdrain: 15.3
- Beneficial Uses: Cold Freshwater Habitat (COLD), Warm Freshwater Habitat (WARM), Fish Migration (MIGR), Fish Spawning (SPWN), Wildlife Habitat (WILD)
- Water Quality Impairments: Urban Pesticide Toxicity (Diazinon), Sedimentation, Trash