Pilarcitos Creek (Spanish for: ''Little Pillars or Pillaries Creek'') is a U.S. Geological Survey. National Hydrography Dataset high-resolution flowline data
The National Map
, accessed March 15, 2011

coast The coast, also known as the coastline or seashore, is defined as the area where land meets the ocean, or as a line that forms the boundary between the land and the coastline. The Earth has around of coastline. Coasts are important zones in ...

al stream in

San Mateo County, California San Mateo County ( ), officially the County of San Mateo, is a county located in the U.S. state of California. As of the 2020 census, the population was 764,442. Redwood City is the county seat, and the third most populated city following Dal ...

, United States, that rises on the western slopes of the Santa Cruz Mountains and descends through Pilarcitos Canyon to discharge into the

Pacific Ocean The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the contin ...

Half Moon Bay State Beach Half Moon Bay State Beach is a stretch of protected beaches in the state park system of California, United States, on Half Moon Bay. From north to south it comprises Roosevelt, Dunes, Venice, and Francis Beaches. The park was established in ...

. The Pilarcitos Creek watershed is a significant area of ecological, cultural and economic diversity. It is a source of clean drinking water for residents of the central coast and San Francisco Bay Area and supports several natural-resource based economies – including agriculture and recreational tourism. The watershed is also experiencing increased competition for water between agricultural, domestic, recreational, commercial and environmental uses.

History

The Portolà expedition camped on the creek on October 28, 1769, and Father Juan Crespí named it Arroyo de San Simon y San Judas in honor of the Catholic Feast day for the Apostles

Simon Simon may refer to: People * Simon (given name), including a list of people and fictional characters with the given name Simon * Simon (surname), including a list of people with the surname Simon * Eugène Simon, French naturalist and the genus ...

and Jude. The name Arroyo de los Pilarcitos meaning "creek of the little pillar-like rocks" was recorded in land grant papers as early as 1836. In recent history, public and private stakeholders in the watershed have been working together intermittently since 1992, when two separate pollution discharge events occurred. Settlements from pollution discharge events initiated a trust fund for restoration activities. Associated money was used to develop the 1996 Pilarcitos Creek Restoration Plan. The Pilarcitos Creek Advisory Committee (PCAC) was created as a citizens advisory committee to provide input on the development of the Plan, and to provide advice and guidance to the Project Manager, the San Mateo County Resource Conservation District (RCD). In 2005, a group of over 20 local and regional agencies and advocacy groups gathered with nearly 200 members of the community at a water summit to discuss watershed-based approaches for balancing the beneficial uses of water in Pilarcitos Creek. In January 2007 watershed stakeholders established the Pilarcitos Creek Restoration Workgroup to guide the development of an Integrated Watershed Management Plan (IWMP) to promote balanced solutions to effectively manage the Pilarcitos Creek watershed that satisfy environmental, public health, domestic water supply, and economic interests.

Watershed description

The Pilarcitos Creek watershed drains . The creek begins at on the south slope of Whiting Ridge east of the North Peak of

Montara Mountain Montara Mountain, positioned between the unincorporated community of Montara, California, to the southwest and the city of Pacifica, California, to the north, forms the northern spur of the Santa Cruz Mountains, a narrow mountain range running the ...

, flows east-southeast, to Pilarcitos Reservoir where it is joined by Spring Valley Creek. Pilarcitos Dam was built in 1864 and two miles downstream Stone Dam was built in 1871. Further downstream, Pilarcitos Creek is joined by Albert Gulch in Albert Canyon at Highway 92. Albert Gulch is named for the ranch of the William C. Albrecht family, who lived here from the 1870s until 1954. Here Pilarcitos Creek turns to flow southwest for to the community of

Half Moon Bay Half Moon Bay is a coastal city in San Mateo County, California, United States, approximately south of San Francisco. Its population was 11,795 as of the 2020 census. Immediately at the north of Half Moon Bay is Pillar Point Harbor and the un ...

. Along the way it is joined on the right (heading downstream) by Nuff Creek, Corinda Los Trancos Creek, and Apanolio Creek, then from the left by Madonna Creek and Arroyo León before heading and west-northwest for to enter Half Moon Bay and the Pacific Ocean at Elmar Beach. The maximum rate of discharge was recorded as . As early as 1860 a major diversion of Pilarcitos Creek was constructed to supply water to the burgeoning population of

San Francisco San Francisco (; Spanish for " Saint Francis"), officially the City and County of San Francisco, is the commercial, financial, and cultural center of Northern California. The city proper is the fourth most populous in California and 17th ...

. Two different tunnels carry water east from Pilarcitos Lake Reservoir and Stone Dam Reservoir, respectively. At the present time Pilarcitos Creek not only continues to supply water to

and the Peninsula via the

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 H ...

, but it is also the principal source of potable water for the city of

and coastside vicinity. Jurisdiction over land use decisions in the lower creek regions is under the city of Half Moon Bay. Land use decisions in the upper reaches are with the

San Mateo County San Mateo County ( ), officially the County of San Mateo, is a county located in the U.S. state of California. As of the 2020 census, the population was 764,442. Redwood City is the county seat, and the third most populated city following Daly ...

. Both entities administer provisions of California's Local Coastal Program.

Watershed condition

The Pilarcitos Creek watershed is host to a number of plant and animal species, including anadromous

steelhead trout Steelhead, or occasionally steelhead trout, is the common name of the anadromous form of the coastal rainbow trout or redband trout (O. m. gairdneri). Steelhead are native to cold-water tributaries of the Pacific basin in Northeast Asia and ...

(''Oncorhynchus mykiss'') which are listed as "threatened" by the Federal government. Over recent history, physical and biological impacts resulting from human activity have degraded the overall watershed condition, threatening native plant and animal species including steelhead. In addition, water demand has increased with the growth of residential, agricultural, and industrial development in the Pilarcitos Creek watershed, decreasing the amount of water available for surface flow in streams. Several key watershed management issues were identified in 2008 following a review of information about the existing state of the watershed. The key watershed management issues include: -Instream flows to support aquatic resources during critical summer and fall periods. -Other ecosystem factors, including fish passage, instream habitat, watershed erosion, channel maintenance, riparian vegetation, exotic invasive species, and the spring estuary/summer lagoon. -Social issues, including community engagement, landowner concerns, beach quality, and landfill issues.

Fecal coliform A fecal coliform (British: faecal coliform) is a facultatively anaerobic, rod-shaped, gram-negative, non-sporulating bacterium. Coliform bacteria generally originate in the intestines of warm-blooded animals. Fecal coliforms are capable of growth ...

levels at the mouth periodically violate State of California

water quality Water quality refers to the chemical, physical, and biological characteristics of water based on the standards of its usage. It is most frequently used by reference to a set of standards against which compliance, generally achieved through tr ...

standards. The Pilarcitos Creek watershed holds a considerable

biodiversity Biodiversity or biological diversity is the variety and variability of life on Earth. Biodiversity is a measure of variation at the genetic (''genetic variability''), species (''species diversity''), and ecosystem (''ecosystem diversity'') l ...

and is confirmed

habitat In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...

for the

endangered An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and in ...

San Francisco garter snake The San Francisco garter snake (''Thamnophis sirtalis tetrataenia'') is a slender multi-colored subspecies of the common garter snake. Designated as an endangered subspecies since the year 1967, it is endemic to San Mateo County and the extrem ...

.''Biology and Limits of Vegetation, Pilarcitos Creek, Half Moon Bay'', Earth Metrics Inc., city of Half Moon Bay report 10282, Oct.11, 1989 arroyo willow (''Salix lasiolepis'') and

red alder ''Alnus rubra'', the red alder, is a deciduous broadleaf tree native to western North America (Alaska, Yukon, British Columbia, Washington, Oregon, California, Idaho and Montana). Description Red alder is the largest species of alder in Nort ...

(''Alnus rubra'') are the dominant riparian trees in the lower watershed, with coast Douglas fir (''Pseudotsuga menziesii var. menziesii'') forest.

Integrated management plan

The IWMP provides a set of recommendations for projects that help to achieve the goals set forward in the plan. The purpose of the IWMP is to promote balanced solutions to effectively manage the Pilarcitos Creek watershed that satisfy environmental, public health, domestic water supply, and economic interests. It prioritizes restoration projects that individually or collectively help to achieve six key goals: 1. Protect and recover Steelhead trout and other native aquatic and riparian species 2. Enhance streamflows while maintaining yield 3. Manage stream channel corridors to reduce erosion, sedimentation and flood risks 4. Increase native riparian vegetation 5. Maintain good water quality conditions 6. Promote community and stakeholder collaboration For each goal, a series of objectives offers more specific guidance about how each goal will be achieved. The goals and objectives reflect agreement by the workgroup achieved through an ongoing dialogue and public input. Together, the goals and objectives provide a foundation for the implementation strategy and plan.

Pilarcitos Restoration Workgroup

Implementation of the IWMP continues to be driven by the Pilarcitos Restoration Workgroup and the collaboration among IWMP stakeholders. The purpose of the Workgroup is to work as partners to promote balanced management solutions in the watershed. Current Workgroup members are California Department of Fish and Wildlife, California State Parks, City of Half Moon Bay, Coastside County Water District, Coastside Land Trust, Committee for Green Foothills, Midpeninsula Regional Open Space District, National Marine Fisheries Service,

Peninsula Open Space Trust The Peninsula Open Space Trust (POST) is a nonprofit land trust headquartered in Palo Alto, California. Mission and Work POST mission is to protect open space on the Peninsula and in the South Bay for the benefit of all. The organization has bee ...

, Pilarcitos Creek Advisory Committee, San Francisco Public Utilities Commission, San Mateo County, San Mateo County Farm Bureau, San Mateo County Resource Conservation District, Sewer Authority Mid-Coastside, and Surfrider Foundation - San Mateo Chapter. The RCD convenes the Workgroup.

References

External links

San Mateo County Resource Conservation District home page

Committee for Green Foothills

National Oceanic and Atmospheric Administration

U.S. Fish and Wildlife Service

Coastside County Water District

San Francisco Water Power Sewer, Services of San Francisco Public Utilities Commission

California Department of Fish and Game

USDA Natural Resources Conservation Service

California Department of Parks and Recreation

San Mateo County

City of Half Moon Bay

Sound Watershed

Surfrider Foundation

Sewer Authority Mid-Coastside

PWA ESA
{{Santa Cruz Mountains Rivers of San Mateo County, California Santa Cruz Mountains Rivers of Northern California