Pinole Creek is a

stream A stream is a continuous body of water, body of surface water Current (stream), flowing within the stream bed, bed and bank (geography), banks of a channel (geography), channel. Depending on its location or certain characteristics, a strea ...

in western

Contra Costa County Contra Costa County (; ''Contra Costa'', Spanish language, Spanish for 'Opposite Coast') is a U.S. county, county located in the U.S. state of California, in the East Bay of the San Francisco Bay Area. As of the 2020 United States census, the ...

, in the

East Bay The East Bay is the eastern region of the San Francisco Bay Area and includes cities along the eastern shores of San Francisco Bay and San Pablo Bay. The region has grown to include inland communities in Alameda and Contra Costa counties. Wi ...

region of the

San Francisco Bay Area The San Francisco Bay Area, commonly known as the Bay Area, is a List of regions of California, region of California surrounding and including San Francisco Bay, and anchored by the cities of Oakland, San Francisco, and San Jose, California, S ...

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

. The creek has one of the last primarily undeveloped watersheds in the Bay Area.

Course

The

headwaters The headwater of a river or stream is the geographical point of its beginning, specifically where surface runoff water begins to accumulate into a flowing channel of water. A river or stream into which one or many tributary rivers or streams flo ...

of Pinole Creek are in the

Briones Hills The Briones Hills form a low mountain range in western Contra Costa County, California, Contra Costa County, in the East Bay (San Francisco Bay Area), East Bay region of the San Francisco Bay Area, California, United States. The Briones Hills are ...

on Costa Peak, within the western area of

Briones Regional Park Briones Regional Park is a regional park in the East Bay Regional Park District (EBRPD) system, located in the Briones Hills of central Contra Costa County of the San Francisco Bay Area in California. Geography The park is located in rolling h ...

. It flows westerly through the towns of

Pinole Pinole, also called pinol, is roasted ground maize. The resulting powder is then used as a nutrient-dense ingredient to make different foods, such as cereals, baked goods, tortillas, and beverages. For example, it can be mixed with a combination ...

and El Sobrante, to its

river mouth A river mouth is where a river flows into a larger body of water, such as another river, a lake/reservoir, a bay/gulf, a sea, or an ocean. At the river mouth, sediments are often deposited due to the slowing of the current, reducing the carryin ...

at the Chelsea Wetlands in

Hercules Hercules (, ) is the Roman equivalent of the Greek divine hero Heracles, son of Jupiter and the mortal Alcmena. In classical mythology, Hercules is famous for his strength and for his numerous far-ranging adventures. The Romans adapted the Gr ...

San Pablo Bay San Pablo Bay is a tidal estuary that forms the northern extension of the San Francisco Bay in the East Bay and North Bay regions of the San Francisco Bay Area in northern California. Most of the Bay is shallow; however, there is a deep wate ...

. Its mouth is east of

Point Pinole Point Pinole Regional Shoreline is a regional park on the shores of the San Pablo Bay, California (the northern arm of the San Francisco Bay), in the United States. It is approximately in area, and is operated by the East Bay Regional Park Dis ...

History

The name

is from the Spanish term for "parched corn", which the Mexicans ground for eating. In 1823, a

Mexican land grant In Alta California (now known as California) and Baja California, ranchos were concessions and land grants made by the Spanish and Mexican governments from 1775 to 1846. The Spanish concessions of land were made to retired soldiers as an indu ...

for that included Pinole Creek was granted to Don Ignacio Martinez, a Commandant of the

San Francisco Presidio The Presidio of San Francisco (originally, El Presidio Real de San Francisco or The Royal Fortress of Saint Francis) is a park and former U.S. Army post on the northern tip of the San Francisco Peninsula in San Francisco, California, and is part ...

. The land grant was initially known as ''El Rancho de La Nuestra Sonora de Merced'', and later renamed

Rancho El Pinole Rancho El Pinole was a Mexican land grant along Carquinez Strait in present-day Contra Costa County, California. It was given in 1842 by Governor Juan Alvarado to Ygnacio Martinez, a Californio military commander and politician. Rancho El Pino ...

. Martinez built the first adobe in Pinole Valley and brought his family to settle the property with livestock and orchards.

Watershed

The upper watershed contains large areas of open space and managed grazing lands, with ranching and agricultural activities, and residential equestrian properties. The lower watershed contains the historic Old Town District of

, and suburban neighborhoods in Pinole, El Sobrante, and

. The watershed follows the regional geologic northwest–southeast orientation, similar to the orientation of the

Berkeley Hills The Berkeley Hills are a range of the Pacific Coast Ranges, and overlook the northeast side of the valley that encompasses San Francisco Bay. They were previously called the "Contra Costa Range/Hills" (from the original Spanish ''Sierra de la Co ...

, and is located just northeast of the Sobrante Ridge. The watershed is approximately in area, extending from headwaters on Costa and Duarte Peaks in the

, northwest to the

just east of Wilson Point. The average annual rainfall for the Pinole Creek watershed is 610 mm (24 in), with 90% falling between November and April. There are twelve minor, locally named tributaries and the gradient is 1%. In 1965, the Army Corps of Engineers armored the creek channel between

Interstate 80 Interstate 80 (I-80) is an east–west transcontinental freeway that crosses the United States from San Francisco, California, to Teaneck, New Jersey, in the New York metropolitan area. The highway was designated in 1956 as one of the ori ...

and San Pablo Bay for flood control. However, this removed

riparian zone A riparian zone or riparian area is the interface between land and a river or stream. In some regions, the terms riparian woodland, riparian forest, riparian buffer zone, riparian corridor, and riparian strip are used to characterize a ripari ...

vegetation and tree cover needed for food, shelter, and shade for fish and other wildlife.

Ecology

Fauna

Biologists from the

East Bay Municipal Utility District East Bay Municipal Utility District (EBMUD), colloquially referred to as "East Bay Mud", is a public utility district which provides water and sewage treatment services for an area of approximately in the eastern side of San Francisco Bay.Sectio ...

(EBMUD) have observed

Steelhead trout Steelhead, or occasionally steelhead trout, is the anadromous form of the coastal rainbow trout or Columbia River redband trout (''O. m. gairdneri'', also called redband steelhead). Steelhead are native to cold-water tributaries of the Pacif ...

(''Oncorhyncus mykiss'') in the Pinole Creek watershed of multiple ages. Genetic studies by EBMUD in 1999 suggest that the trout are native Central California stock and not introduced. Perennial flows are jeopardized by water usage in the upper watershed but the creek may have the best trout restoration potential in the East Bay because large portions of the watershed are in open space. However, the I-80 crossing may be a significant obstacle to upstream trout migration. Pinole Creek supports a mostly native fish assemblage including rainbow/steelhead trout,

California roach The California roach (previously ''Lavinia/Hesperoleucus symmetricus'') is a species of freshwater Actinopterygii, ray-finned fish belonging to the Family (biology), family Leuciscidae, which includes the daces, chubs, Phoxinus, Eurasian minnows ...

(''Lavinia symmetricus''), Sacramento sucker (''

Catostomus ''Catostomus'' is a genus of fish belonging to the family Catostomidae, commonly known as suckers. This genus of fish usually lives in freshwater basins. Most members of the genus are native to North America, but '' C. catostomus'' is also found ...

occidentalis''),

Threespine stickleback The three-spined stickleback (''Gasterosteus aculeatus'') is a fish native to most inland and coastal waters north of 30°N. It has long been a subject of scientific study for many reasons. It shows great morphological variation throughout its ra ...

(''Gasterosteus aculeatus''), Prickly sculpin ('' Cottus asper'').

Mosquitofish The western mosquitofish (''Gambusia affinis'') is a North American freshwater poeciliid fish, also known commonly, if ambiguously, as simply mosquitofish or by its generic name, ''Gambusia'', or by the common name gambezi. Its sister species ...

(''Gambusia affinis'') and

Common carp The common carp (''Cyprinus carpio''), also known as European carp, Eurasian carp, or simply carp, is a widespread freshwater fish of eutrophic waters in lakes and large rivers in Europe and Asia.Fishbase''Cyprinus carpio'' Linnaeus, 1758/ref>Ark ...

(''Cyprinus carpio'') are nonnative fishes found predominantly in the lower section of Pinole Creek, below Interstate 80.

Flora

Native plants are species of the

California chaparral and woodlands The California chaparral and woodlands is a terrestrial ecoregion of southwestern Oregon, northern, central, and southern California (United States) and northwestern Baja California (Mexico), located on the west coast of North America. It is a ...

and

riparian forest A riparian forest or riparian woodland is a forested or wooded area of land adjacent to a body of water such as a river, stream, pond, lake, marshland, estuary, canal, Sink (geography), sink, or reservoir. Due to the broad nature of the definitio ...

habitats. Invasive plant species such as

Giant reed ''Arundo donax'' is a tall perennial cane. It is one of several so-called reed species. It has several common names including giant cane, elephant grass, carrizo, arundo, Spanish cane, Colorado river reed, wild cane, and giant reed. ''Arundo'' a ...

(''Arundo donax''),

Scotch broom ''Cytisus scoparius'' ( syn. ''Sarothamnus scoparius''), the common broom or Scotch broom, is a deciduous leguminous shrub native to western and central Europe. In Great Britain and Ireland, the standard name is broom; this name is also used fo ...

(''Cytisus scoparius''),

Yellow star thistle Yellow is the color between green and orange on the spectrum of light. It is evoked by light with a dominant wavelength of roughly 575585 nm. It is a primary color in subtractive color systems, used in painting or color printing. In the R ...

(''Centaurea solstitialis''),

Himalayan blackberry ''Rubus armeniacus'', the Himalayan blackberry or Armenian blackberry, is a species of ''Rubus'' in the blackberry group ''Rubus'' subgenus ''Rubus'' series ''Discolores'' (P.J. Müll.) Focke. It is native to Armenia and northern Iran, and widel ...

(''Rubus discolor'') and many others are established along

sections of Pinole Creek.

References

External links

Friends of Pinole Creek

{{East Bay Rivers of Contra Costa County, California Tributaries of San Pablo Bay El Sobrante, Contra Costa County, California Hercules, California Pinole, California Rivers of Northern California