San Andreas Creek
Encyclopedia
San Andrés Creek now called San Andreas Creek, is a perennial stream that flows 5.9 miles (9.5 km) miles southeasterly along the San Andreas Fault
from Sweeney Ridge
in San Mateo County, California
, providing the inflow to and outflow from San Andreas Reservoir, and then entering Lower Crystal Springs Reservoir
, where it was a historic tributary to San Mateo Creek. San Mateo Creek then carries its waters over Crystal Springs Dam northeast to San Francisco Bay
.
on November 4, 1769, the Portolà expedition
descended what Portolà
called the Cañada de San Francisco, now known as San Andreas Creek, to camp just south of the San Mateo Creek canyon on a lake called by him Laguna Grande, now covered by Upper Crystal Springs Reservoir
. The campsite is marked by California Historical Marker No. 94 "Portola Expedition Camp", located at Crystal Springs Dam, on Skyline Boulevard, 0.1 mi south of Crystal Springs Road. After heading south and descending from the foothills along San Francisquito Creek
to established his base camp at El Palo Alto
, Portola retraced his steps and returned along San Andreas Creek to recross Sweeney Ridge and then via the coast back to San Diego
. The San Andres Creek place name is shown on the Rancho de las Pulgas
1856 plat map. Padre Palóu
, on an expedition from Monterey to explore the western side of San Francisco Bay led by Captain Rivera
, renamed Portola's Cañada de San Francisco to Cañada de San Andrés on November 30, 1774, it being the feast day of St. Andrew. Captain Juan Bautista de Anza
, after forging the first overland route from Monterey, California
to San Francisco Bay, explored the peninsula and selected the sites for Mission San Francisco de Asís
(Mission Dolores) and the Presidio of San Francisco
. De Anza returned to Monterey via the Cañada de San Andrés and camped on the banks of San Mateo Creek
on March 29, 1776. In de Anza's diary on March 29, 1776, he wrote: "Night having fallen, at a quarter past six I went down to the arroyo of San Andreas and to another, that of San Matheo, where it descends to empty into the estuary."
The two Crystal Springs lakes and San Andreas Lake used to be known as Spring Valley Lakes for the Spring Valley Water Company which owned them. The Spring Valley Water Company named the lakes, the Spring Valley Lakes, after the company. The original Spring Valley was between Mason and Taylor Streets, and Washington and Broadway Streets in San Francisco
, where the water company started. When the company went south for more water, the Spring Valley name was carried south too.
from which it flows southeasterly along the San Andreas Rift between Sweeney Ridge
to the west and Buri Buri Ridge
to the east, through San Andreas Reservoir, which was formed by the construction of a 100 foot high earth dam in 1868. The San Andreas Dam eliminates flow in the creek immediately below the dams, except for occasional spills or releases from the reservoir and seepage through the dam. From San Andreas Reservoir, the creek descends and enters the northeast arm of Lower Crystal Springs Reservoir
. Historically San Andreas Creek joined San Mateo Creek just above the current location of the Crystal Springs Dam
. The two Crystal Springs lakes and San Andreas Lake used to be known as Spring Valley Lakes for the Spring Valley Water Company which owned them. Lower Crystal Springs Reservoir now covers the town of Crystal Springs which grew up around a resort of the same name.
may play a key role in the precipitation in the upper watershed. On Cahill Ridge (just west of San Mateo Creek and east of Pilarcitos Creek
, at an altitude of 1,000 feet, Oberlander measured fog drip beneath Tanoak
(Lithocarpus densiflorus), Coast redwood and three Douglas fir trees, the latter 125 feet tall. He found that the trees most exposed produced the most precipitation and in five weeks of measurement (July 20-August 28, 1951) fog drip below the tanoak produced 59 inches of precipitation, more than the total annual precipitation on nearby grasslands and chaparral. The Douglas fir produced 7-17 inches of fog drip and appeared to provide unique conditions supporting the orchids Giant helleborine
(Epipactis gigantea) and Phantom orchid
(Cephalanthera austiniae), since these plants were found exclusively in these moist ridge tops.
San Andreas Fault
The San Andreas Fault is a continental strike-slip fault that runs a length of roughly through California in the United States. The fault's motion is right-lateral strike-slip...
from Sweeney Ridge
Sweeney Ridge
Sweeney Ridge, a national park in Pacifica, California, is part of the Golden Gate National Recreation Area. Historically, the ridge was the location of the San Francisco Bay Discovery Site, as part of the Portolá Expedition on November 4, 1769.-Description:...
in San Mateo County, California
San Mateo County, California
San Mateo County is a county located in the San Francisco Bay Area of the U.S. state of California. It covers most of the San Francisco Peninsula just south of San Francisco, and north of Santa Clara County. San Francisco International Airport is located at the northern end of the county, and...
, providing the inflow to and outflow from San Andreas Reservoir, and then entering Lower Crystal Springs Reservoir
Crystal Springs Reservoir
Crystal Springs Reservoir is a pair of artificial lakes located in the northern Santa Cruz Mountains of San Mateo County, California situated in the rift valley created by the San Andreas Fault just to the west of the cities of San Mateo and Hillsborough, and I-280...
, where it was a historic tributary to San Mateo Creek. San Mateo Creek then carries its waters over Crystal Springs Dam northeast to San Francisco Bay
San Francisco Bay
San Francisco Bay is a shallow, productive estuary through which water draining from approximately forty percent of California, flowing in the Sacramento and San Joaquin rivers from the Sierra Nevada mountains, enters the Pacific Ocean...
.
History
After discovering San Francisco Bay from Sweeney RidgeSweeney Ridge
Sweeney Ridge, a national park in Pacifica, California, is part of the Golden Gate National Recreation Area. Historically, the ridge was the location of the San Francisco Bay Discovery Site, as part of the Portolá Expedition on November 4, 1769.-Description:...
on November 4, 1769, the Portolà expedition
Portola expedition
250px|right|Point of San Francisco Bay DiscoveryThe Portolá Expedition was led by Gaspar de Portolá from July 14, 1769 to January 24, 1770. It was the first recorded Spanish land entry and exploration of present day California, United States...
descended what Portolà
Gaspar de Portolà
Gaspar de Portolà i Rovira was a soldier, governor of Baja and Alta California , explorer and founder of San Diego and Monterey. He was born in Os de Balaguer, province of Lleida, in Catalonia, Spain, of Catalan nobility. Don Gaspar served as a soldier in the Spanish army in Italy and Portugal...
called the Cañada de San Francisco, now known as San Andreas Creek, to camp just south of the San Mateo Creek canyon on a lake called by him Laguna Grande, now covered by Upper Crystal Springs Reservoir
Crystal Springs Reservoir
Crystal Springs Reservoir is a pair of artificial lakes located in the northern Santa Cruz Mountains of San Mateo County, California situated in the rift valley created by the San Andreas Fault just to the west of the cities of San Mateo and Hillsborough, and I-280...
. The campsite is marked by California Historical Marker No. 94 "Portola Expedition Camp", located at Crystal Springs Dam, on Skyline Boulevard, 0.1 mi south of Crystal Springs Road. After heading south and descending from the foothills along San Francisquito Creek
San Francisquito Creek
San Francisquito Creek is a creek that flows into southwest San Francisco Bay in California, United States of America. Historically it was called the Arroyo de San Francisco by Juan Bautista de Anza in 1776...
to established his base camp at El Palo Alto
El Palo Alto
El Palo Alto is a coast redwood tree located in El Palo Alto Park on the banks of San Francisquito Creek in Palo Alto, California, United States...
, Portola retraced his steps and returned along San Andreas Creek to recross Sweeney Ridge and then via the coast back to San Diego
San Diego, California
San Diego is the eighth-largest city in the United States and second-largest city in California. The city is located on the coast of the Pacific Ocean in Southern California, immediately adjacent to the Mexican border. The birthplace of California, San Diego is known for its mild year-round...
. The San Andres Creek place name is shown on the Rancho de las Pulgas
Rancho de las Pulgas
Rancho de las Pulgas was a 1795 Spanish land grant in present day San Mateo County, California to José Darío Argüello. The name means "Ranch of the Fleas". The grant was bounded by San Mateo Creek on the north and San Francisquito Creek on the south, and extended about one league from San...
1856 plat map. Padre Palóu
Francisco Palóu
Francesc Palou was a Franciscan missionary, administrator, and historian on the Baja California peninsula and in Alta California. Father Palou's made significant contributions to the Alta California and Baja California mission systems...
, on an expedition from Monterey to explore the western side of San Francisco Bay led by Captain Rivera
Fernando Rivera y Moncada
Fernando Javier Rivera y Moncada was a soldier from New Spain who served in the Baja California peninsula and upper Las Californias, participating in several early overland explorations. Fernando Rivera y Moncada served as a Spanish Miilitary Governor from 1774-1777. -Biography:Rivera was born...
, renamed Portola's Cañada de San Francisco to Cañada de San Andrés on November 30, 1774, it being the feast day of St. Andrew. Captain Juan Bautista de Anza
Juan Bautista de Anza
Juan Bautista de Anza Bezerra Nieto was a Novo-Spanish explorer and Governor of New Mexico for the Spanish Empire.-Early life:...
, after forging the first overland route from Monterey, California
Monterey, California
The City of Monterey in Monterey County is located on Monterey Bay along the Pacific coast in Central California. Monterey lies at an elevation of 26 feet above sea level. As of the 2010 census, the city population was 27,810. Monterey is of historical importance because it was the capital of...
to San Francisco Bay, explored the peninsula and selected the sites for Mission San Francisco de Asís
Mission San Francisco de Asís
Mission San Francisco de Asís, or Mission Dolores, is the oldest surviving structure in San Francisco and the sixth religious settlement established as part of the California chain of missions...
(Mission Dolores) and the Presidio of San Francisco
Presidio of San Francisco
The Presidio of San Francisco is a park on the northern tip of the San Francisco Peninsula in San Francisco, California, within the Golden Gate National Recreation Area...
. De Anza returned to Monterey via the Cañada de San Andrés and camped on the banks of San Mateo Creek
San Mateo Creek
San Mateo Creek is a perennial stream whose watershed includes Crystal Springs Reservoir, for which it is the only natural outlet after passing Crystal Springs Dam.-History:...
on March 29, 1776. In de Anza's diary on March 29, 1776, he wrote: "Night having fallen, at a quarter past six I went down to the arroyo of San Andreas and to another, that of San Matheo, where it descends to empty into the estuary."
The two Crystal Springs lakes and San Andreas Lake used to be known as Spring Valley Lakes for the Spring Valley Water Company which owned them. The Spring Valley Water Company named the lakes, the Spring Valley Lakes, after the company. The original Spring Valley was between Mason and Taylor Streets, and Washington and Broadway Streets in San Francisco
San Francisco, California
San Francisco , officially the City and County of San Francisco, is the financial, cultural, and transportation center of the San Francisco Bay Area, a region of 7.15 million people which includes San Jose and Oakland...
, where the water company started. When the company went south for more water, the Spring Valley name was carried south too.
Watershed
San Andreas Creek's source elevation is at approximately 900 feet (274.3 m) on the eastern slopes of Sweeney RidgeSweeney Ridge
Sweeney Ridge, a national park in Pacifica, California, is part of the Golden Gate National Recreation Area. Historically, the ridge was the location of the San Francisco Bay Discovery Site, as part of the Portolá Expedition on November 4, 1769.-Description:...
from which it flows southeasterly along the San Andreas Rift between Sweeney Ridge
Sweeney Ridge
Sweeney Ridge, a national park in Pacifica, California, is part of the Golden Gate National Recreation Area. Historically, the ridge was the location of the San Francisco Bay Discovery Site, as part of the Portolá Expedition on November 4, 1769.-Description:...
to the west and Buri Buri Ridge
Rancho Buri Buri
Rancho Buri Buri was a Mexican land grant in present day San Mateo County, California given in 1835 by Governor José Castro to José Antonio Sánchez. The name derives from the Urebure village of the Ramaytush speaking Yelamu tribe of Ohlone people who were settled by the banks of San Bruno Creek...
to the east, through San Andreas Reservoir, which was formed by the construction of a 100 foot high earth dam in 1868. The San Andreas Dam eliminates flow in the creek immediately below the dams, except for occasional spills or releases from the reservoir and seepage through the dam. From San Andreas Reservoir, the creek descends and enters the northeast arm of Lower Crystal Springs Reservoir
Crystal Springs Reservoir
Crystal Springs Reservoir is a pair of artificial lakes located in the northern Santa Cruz Mountains of San Mateo County, California situated in the rift valley created by the San Andreas Fault just to the west of the cities of San Mateo and Hillsborough, and I-280...
. Historically San Andreas Creek joined San Mateo Creek just above the current location of the Crystal Springs Dam
Crystal Springs Dam
Crystal Springs Dam is a gravity dam constructed across the San Mateo Creek, impounding water to form the Lower Crystal Springs Reservoir in San Mateo County, California....
. The two Crystal Springs lakes and San Andreas Lake used to be known as Spring Valley Lakes for the Spring Valley Water Company which owned them. Lower Crystal Springs Reservoir now covers the town of Crystal Springs which grew up around a resort of the same name.
Ecology
Fog dripFog drip
Fog drip is a type of precipitation that forms when fog droplets condense on the needles or leaves of trees or other objects, and drips to the ground....
may play a key role in the precipitation in the upper watershed. On Cahill Ridge (just west of San Mateo Creek and east of Pilarcitos Creek
Pilarcitos Creek
Pilarcitos Creek is a coastal stream in San Mateo County, California, USA, that rises on the western slopes of the Santa Cruz Mountains and descends through Pilarcitos Canyon to discharge into the Pacific Ocean at Pilarcitos Creek Beach, a unit of Half Moon Bay State Beach.-History:The Portolà...
, at an altitude of 1,000 feet, Oberlander measured fog drip beneath Tanoak
Tanoak
Tanoak, formerly known taxonomically as Lithocarpus densiflorus, was recently moved into a new genus, Notholithocarpus, based on multiple lines of evidence....
(Lithocarpus densiflorus), Coast redwood and three Douglas fir trees, the latter 125 feet tall. He found that the trees most exposed produced the most precipitation and in five weeks of measurement (July 20-August 28, 1951) fog drip below the tanoak produced 59 inches of precipitation, more than the total annual precipitation on nearby grasslands and chaparral. The Douglas fir produced 7-17 inches of fog drip and appeared to provide unique conditions supporting the orchids Giant helleborine
Epipactis gigantea
Epipactis gigantea is a species of orchid known by the common names stream orchid and giant helleborine. This wildflower is native to western North America from western Canada to central Mexico...
(Epipactis gigantea) and Phantom orchid
Cephalanthera austiniae
Cephalanthera austiniae is a species of orchid known by the common names phantom orchid and snow orchid because the entire plant is white. Native to the western United States and Canada, it is the only species of genus Cephalanthera found outside of Europe and Asia, and the only one entirely...
(Cephalanthera austiniae), since these plants were found exclusively in these moist ridge tops.
See also
- List of watercourses in the San Francisco Bay Area
- San Andreas Reservoir
- San Mateo Creek