Watershed (noun) – an area of land that catches rain draining into a common waterway such as a river, creek, or reservoir.
San Francisquito Creek and its tributaries drain a funnel-shaped area covering 47.5 square miles on the eastern San Francisco Peninsula. Within this small area, natural processes and human activity have created a landscape of tremendous variety and complexity.
Number of creeks:24, including 3 main tributaries (Los Trancos, Corte Madera, and Bear)
Drainage area: 47.5 square miles (80% in San Mateo County, 20% in Santa Clara County)
Species of interest:Steelhead trout, Western pond turtle, California red-legged frog, San Francisco garter snake, salt marsh harvest mouse
Geological features: San Andreas Fault, Santa Cruz Mountains, soft underlying rock
Local jurisdictions:Portola Valley, parts of Woodside, Menlo Park, East Palo Alto, Palo Alto, and Stanford University, and unincorporated land in the counties of San Mateo and Santa Clara.
Average annual rainfall:
Woodside and Portola Valley area: 30”; Menlo Park, Palo Alto, and East Palo Alto area: 15” Measured at Woodside Fire Station and Palo Alto Fire Station #3 rain gauges
San Francisquito Creek flows:
Average of all flow measurements collected during a given water year.
Highest flow reading taken in a given water year; annual maximum, instantaneous flow measurement.
Average of all flow measurements collected during a given month.
