San Gregorio Creek

Last updated
San Gregorio Creek
Arroyo de San Gregorio, Arroyo Rodrigues [1]
CRW 2419.jpg
San Gregorio State Beach
Relief map of California.png
Red pog.svg
Location of the mouth of San Gregorio Creek at the Pacific Ocean
Location
Country United States
State California
Region San Mateo County
Physical characteristics
SourceConfluence of La Honda Creek and Alpine Creek in the Santa Cruz Mountains
Source confluence 
  location La Honda, California, San Mateo County, United States of America
  coordinates 37°19′45″N122°16′58″W / 37.32917°N 122.28278°W / 37.32917; -122.28278
  elevation320 ft (98 m)
Mouth Pacific Ocean
  location
San Gregorio, California
  coordinates
37°18′36″N122°16′37″W / 37.31000°N 122.27694°W / 37.31000; -122.27694 [2]
  elevation
0 ft (0 m)
Basin features
Tributaries 
  left Alpine Creek
  right La Honda Creek, Harrington Creek, Bogess Creek, El Corte de Madera Creek, Clear Creek, Coyote Creek

San Gregorio Creek (Spanish for: Saint Gregory) is a river in San Mateo County, California. Its tributaries originate on the western ridges of the Santa Cruz Mountains whence it courses southwest through steep forested canyons. The San Gregorio Creek mainstem begins at the confluence of Alpine and La Honda Creeks, whence it flows 12 miles (19 km) through rolling grasslands and pasturelands until it meets the Pacific Ocean at San Gregorio State Beach. It traverses the small unincorporated communities of La Honda, San Gregorio, Redwood Terrace and Sky Londa. [3]

Contents

History

San Gregorio Creek is historically significant as the campsite for Spanish explorer Gaspar de Portolà's expedition from October 24–27, 1769, when he overshot his goal (Monterey Bay) and went on to Pacifica where he ascended Sweeney Ridge and discovered San Francisco Bay. [4] The site is registered as California Historical Landmark 26. The creek was called Arroyo de San Gregorio in Spanish times and later, Arroyo Rodrigues in the 1850s. [1]

Watershed

The San Gregorio watershed is located approximately 11 miles (18 km) south of Half Moon Bay and covers approximately 61 square miles (160 km2). It is the second largest drainage in coastal San Mateo County, with approximately 45 miles (72 km) of "blue line" (perennial) streams. [3] The mainstem of San Gregorio Creek begins at the confluence of Alpine Creek and La Honda Creek in La Honda, and flows 11.8 miles (19.0 km) to its mouth at San Gregorio State Beach in San Gregorio. [5]

The creek ends in a lagoon primarily in the incised channel upstream from the Highway 1 Bridge. The lagoon at its seasonal largest, is about 5 acres (2.0 ha) and 6 feet (1.8 m) deep, and serves as habitat for tidewater goby (Eucyclogobius newberryi)) and rearing steelhead. Coho salmon do not rear in the lagoon but outgoing smolts use it to physiologically prepare for migration to saltwater. [3]

This river floods occasionally on its path down CA Route 84 towards the Pacific Ocean, most famously during the 1997 El Niño.

Ecology

The mainstem of San Gregorio Creek, in combination with its tributaries of La Honda, Alpine, Harrington, El Corte de Madera and Bogess Creeks, contains approximately 33 miles (53 km) of historical coho salmon (Oncorhynchus kisutch) rearing habitat. In the 1800s the creek had large enough salmon runs to support commercial harvest (Skinner, 1962). [3] As part of the southern range of the Central California Coast Coho Evolutionarily Significant Unit (ESU), the creek is considered an attractive site for re-stocking. [5] In fact, in 1998 the Draft Strategic Plan for Restoration of Endangered Coho Salmon South of San Francisco Bay identified San Gregorio Creek and its tributaries as one of nine creeks in which recovery of coho salmon (Oncorhynchus kisutch) is a priority. [6] South of San Francisco to Monterey Bay the coho salmon was listed by the State of California as endangered in 1995. The San Gregorio watershed has seen recently increasing residential development but remains primarily pastoral with cattle and sheep grazing, timber harvesting, and recreational trails being the main commercial uses. Because of the large private ownership and development potential, water diversions and low base flows are an important issue in this watershed. In 1993, water rights in the San Gregorio watershed were adjudicated and a minimum stream bypass flow was established. However, the prescribed bypass flows are too low to assure viable coho salmon populations. [5]

San Gregorio Creek is also part of the Central California Coast steelhead (Oncorhynchus mykiss irideus) ESU and historically supported a run of 1,000 fish as recently as 1971. [7]

In 2007, the San Gregorio Creek watershed was targeted by the California Department of Fish and Game for salmon recovery. [8]

In a 2008 survey, both coho salmon and steelhead were noted in the creek but threatened by Highway 84 related barriers to fish passage, as well as pressure from sedimentation from residential development, grazing and logging. The primary threat to salmonids in this report were bridge culverts at three sites which impede fish passage during low creek flows, and one site where a culvert from a small tributary is completely impassable in any season. [9]

Four special-status animal species - California red-legged frog (Rana draytonii), coho salmon, steelhead, and tidewater goby are the focus of a June 2010 Watershed Management Plan. [3]

Western leatherwood (Dirca occidentalis), Santa Cruz manzanita (Arctostaphylos andersonii), and King's Mountain manzanita (Arctostaphylos regismontana), which are all included in the California Native Plant Society's Inventory of Rare and Endangered Plants of California , have been documented in the La Honda Creek Open Space Preserve.

Tributaries

From mouth to head:

See also

Related Research Articles

<span class="mw-page-title-main">Napa River</span> River in California, United States

The Napa River is a river approximately 55 miles (89 km) long in the U.S. state of California. It drains a famous wine-growing region called the Napa Valley, in the mountains north of the San Francisco Bay. Milliken Creek and Mt. Veeder watersheds are a few of its many tributaries. The river mouth is at Vallejo, where the intertidal zone of fresh and salt waters flow into the Carquinez Strait and the San Pablo Bay.

<span class="mw-page-title-main">Waddell Creek (California)</span> River in California, United States

Waddell Creek is the name given to both the creek and the watershed that run through Big Basin Redwoods State Park in Santa Cruz County, California. The Waddell Creek mainstem is formed by the confluence of East and West Waddell Creeks, and empties into the Pacific Ocean at Waddell Beach, just south of Año Nuevo Point.

<span class="mw-page-title-main">Lagunitas Creek</span> Stream in California, United States

Lagunitas Creek is a 24 miles (39 km)-long northward-flowing stream in Marin County, California. It is critically important to the largest spawning runs of endangered coho salmon in the Central California Coast Coho salmon Evolutionary Significant Unit.

<span class="mw-page-title-main">Alameda Creek</span> River in California, United States

Alameda Creek is a large perennial stream in the San Francisco Bay Area. The creek runs for 45 miles (72 km) from a lake northeast of Packard Ridge to the eastern shore of San Francisco Bay by way of Niles Canyon and a flood control channel. Along its course, Alameda Creek provides wildlife habitat, water supply, a conduit for flood waters, opportunities for recreation, and a host of aesthetic and environmental values. The creek and three major reservoirs in the watershed are used as water supply by the San Francisco Public Utilities Commission, Alameda County Water District and Zone 7 Water Agency. Within the watershed can be found some of the highest peaks and tallest waterfall in the East Bay, over a dozen regional parks, and notable natural landmarks such as the cascades at Little Yosemite and the wildflower-strewn grasslands and oak savannahs of the Sunol Regional Wilderness. After an absence of half a century, ocean-run steelhead trout are able to return to Alameda Creek to mingle with remnant rainbow trout populations. Completion of a series of dam removal and fish passage projects, along with improved stream flows for cold-water fish and planned habitat restoration, enable steelhead trout and Chinook salmon to access up to 20 miles (32 km) of spawning and rearing habitat in Alameda Creek and its tributaries. The first juvenile trout migrating downstream from the upper watershed through lower Alameda Creek toward San Francisco Bay was detected and documented in April 2023.

<span class="mw-page-title-main">San Francisquito Creek</span> River in California, United States

San Francisquito Creek is a creek that flows into southwest San Francisco Bay in California, United States. Historically it was called the Arroyo de San Francisco by Juan Bautista de Anza in 1776. San Francisquito Creek courses through the towns of Portola Valley and Woodside, as well as the cities of Menlo Park, Palo Alto, and East Palo Alto. The creek and its Los Trancos Creek tributary define the boundary between San Mateo and Santa Clara counties.

<span class="mw-page-title-main">Redwood Creek (Marin County)</span> River in California, United States

Redwood Creek is a mostly perennial stream in Marin County, California. 4.7 miles (7.6 km) long, it drains a 7-square-mile (18 km2) watershed which includes the Muir Woods National Monument, and reaches the Pacific Ocean north of the Golden Gate at Muir Beach.

San Leandro Creek is a 21.7-mile-long (34.9 km) year-round natural stream in the hills above Oakland in Alameda County and Contra Costa County of the East Bay in northern California.

<span class="mw-page-title-main">Arroyo Corte Madera del Presidio</span> River in California, United States

Arroyo Corte Madera del Presidio is a 4.1-mile-long (6.6 km) year-round stream in southern Marin County, California, United States. This watercourse is also known as Corte Madera Creek, although the actual stream of that name flows into San Francisco Bay further north at Point San Quentin. This watercourse has a catchment basin of about 8 square miles (21 km2) and drains the south-eastern slopes of Mount Tamalpais and much of the area in and around the town of Mill Valley; this stream discharges to Richardson Bay.

<span class="mw-page-title-main">La Honda Creek</span> River in California, United States

La Honda Creek is a 7 miles (11 km) long stream on the Pacific slope of the Santa Cruz Mountains and is a tributary of San Gregorio Creek. From its source near Bear Gulch Road and Skyline Boulevard (CA 35) in San Mateo County, California, La Honda Creek's water flow south to its confluence with Alpine Creek to form San Gregorio Creek in La Honda, and thence to the Pacific Ocean.

Weeks Creek is a small creek tributary to La Honda Creek, which in turn is tributary to San Gregorio Creek in western San Mateo County, California. San Gregorio Creek drains to the Pacific Ocean at San Gregorio State Beach. The San Gregorio Creek watershed supports several species listed under the federal and State of California Endangered Species Acts. These species include—coho salmon (endangered), steelhead (threatened), Tidewater Goby, San Francisco Garter Snake, and California Red-legged frog.

<span class="mw-page-title-main">Pescadero Creek</span> River in California, United States

Pescadero Creek is a major stream in Santa Cruz and San Mateo counties in California, United States. At 26.6 miles (42.8 km), it is the longest stream in San Mateo County and flows all year from springs in the Santa Cruz Mountains. Its source is at 1,880 feet (570 m) above sea level on the western edge of Castle Rock State Park, with additional headwaters in Portola Redwoods State Park, and its course traverses Pescadero Creek County Park and San Mateo County Memorial Park before entering Pescadero Marsh Natural Preserve at Pescadero State Beach and thence to the Pacific Ocean 14.4 miles (23 km) south of Half Moon Bay.

Walker Creek is a northwest-flowing stream in western Marin County, California, United States. It originates at the confluence of Salmon Creek and Arroyo Sausal, and empties into Tomales Bay south of Dillon Beach, California.

Pine Gulch Creek is a 7.6-mile-long (12.2 km) south-flowing stream in western Marin County, California, United States which empties into Bolinas Lagoon.

<span class="mw-page-title-main">Boise Creek</span> River in California, United States

Boise Creek is a stream in Humboldt County, California, United States. From its origin on Orleans Mountain it flows 8.5 miles to join the Klamath River about 2.25 miles southeast of Orleans, California. The creek lies within the Six Rivers National Forest and is part of the Lower Klamath River Watershed.

<span class="mw-page-title-main">Searsville Dam</span> Dam in California, USA

Searsville Dam is a masonry dam in San Mateo County, California that was completed in 1892, one year after the founding of Stanford University, and impounds Corte Madera Creek to form a reservoir known as Searsville Reservoir or Searsville Lake. Searsville Dam is located in the Jasper Ridge Biological Preserve and is owned and operated by Stanford University. Neighboring cities include Woodside and Portola Valley, California.

<span class="mw-page-title-main">Corte Madera Creek (San Mateo County)</span> River in California, United States

Corte Madera Creek is a 7.3-mile-long (11.7 km) creek that flows north-northwest to Searsville Dam and then joins with Bear Creek to form San Francisquito Creek in California.

<span class="mw-page-title-main">Bear Creek (San Francisquito Creek tributary)</span> River in California, United States

Bear Creek, or Bear Gulch Creek, is a 6.6-mile-long (10.6 km) southeastward-flowing stream originating north of the summit of Sierra Morena in the Santa Cruz Mountains, near the community of Kings Mountain in San Mateo County, California, United States. It flows through the town of Woodside. Bear Creek and Corte Madera Creek join to become San Francisquito Creek in the Jasper Ridge Biological Preserve at Stanford University.

<span class="mw-page-title-main">Scott Creek (Santa Cruz County)</span> River in California, United States

Scott Creek, also called Scotts Creek, is a 12.2-mile-long (19.6 km) stream and surfspot in Santa Cruz County, California. It is a few miles north of Davenport and a few miles south of Waddell Creek.

<span class="mw-page-title-main">Aptos Creek</span> Creek in Santa Cruz County, California

Aptos Creek is a southward flowing 9.5 miles (15.3 km) creek that begins on Santa Rosalia Mountain on the southwestern slope of the Santa Cruz Mountains in Santa Cruz County, California and enters Monterey Bay, at Seacliff State Beach in Aptos, California.

Chileno Creek is a stream in western Marin County, California, United States. It originates west of Petaluma, California at 220-acre Laguna Lake which straddles Marin and Sonoma Counties, from which it flows west 6.25 kilometres (3.88 mi) before joining Walker Creek, a tributary of Tomales Bay.

References

  1. 1 2 Durham, David L. (1998). Durham's Place Names of California's San Francisco Bay Area: Includes Marin, San Francisco, San Mateo, Contra Costa, Alameda, Solano & Santa Clara counties. Word Dancer Press, Sanger, California. p. 156. ISBN   1-884995-14-4.
  2. U.S. Geological Survey Geographic Names Information System: San Gregorio Creek
  3. 1 2 3 4 5 Carson Cox; Elizabeth Soderstrom (June 2010). San Gregorio Creek Watershed Management Plan (PDF) (Report). Natural Heritage Institute. Retrieved 2010-11-10.
  4. Syd Whittle. "Portola Camp, The Historical Marker Database" . Retrieved Apr 4, 2010.
  5. 1 2 3 Recovery Units and Watersheds, Chapter Six in Coho Salmon: Recovery Strategy for California (PDF) (Report). California Department of Fish and Game. Feb 4, 2004. p. 6.46. Archived from the original (PDF) on 2010-04-27. Retrieved Apr 4, 2010.
  6. R. H. Brady III; S. Pearce; L. McKee; S. Overton; C. Striplen (2004). Fluvial geomorphology, hydrology, and riparian habitat of La Honda Creek along the Highway 84 transportation corridor, San Mateo County, California (Report). Oakland, California: San Francisco Estuary Institute (SFEI). Archived from the original on 2010-11-14. Retrieved 2010-11-10.
  7. Coots, M. (Jan 1973). A Study of Juvenile Steelhead, Salmon gairdnerii gairdnerii Richardson, in San Gregorio Creek and Lagoon, San Mateo County, March Through August 1971 (Report). California Department of Fish and Game Report No. 73-4.
  8. County Road Maintenance Guidelines for Protecting Aquatic Habitat and Salmon Fisheries (PDF) (Report). FishNet4C, MFG Inc, and Pacific Watershed Associates. 2007. Retrieved Apr 4, 2010.
  9. Alford, Chris (2008). Parallel passageways: An assessment of salmon migration in the San Gregorio watershed (Report). UC Berkeley: Water Resources Center Archives. Retrieved Apr 4, 2010.