Sonoma Creek
Encyclopedia
Sonoma Creek is a 33.4 miles (53.8 km) stream
in northern California
. It is one of two principal drainages of southern Sonoma County, California
, with headwaters rising in the rugged hills of Sugarloaf Ridge State Park
and discharging to San Pablo Bay
, the northern arm of San Francisco Bay
. The watershed drained by Sonoma Creek is roughly equivalent to the wine region of Sonoma Valley
, an area of about 170 square miles (440.3 km²). The State of California
has designated the Sonoma Creek watershed
as a “Critical Coastal Water Resource”. To the east of this generally rectangular watershed is the Napa River
watershed, and to the west are the Petaluma River
and Tolay Creek
watersheds.
This south flowing river
drains the western slopes of the Mayacamas Range, the southern slopes of Annadel State Park
and the eastern slopes of the Sonoma Mountains
with intermittent winter flows in the higher tributary reaches. As the tributaries and headwaters reach the valley floor, a perennial stream cuts through scenic and valuable vineyard
s of Kenwood
. Sonoma Creek veers west at Kenwood and cuts a gorge running parallel to Warm Springs Road, where it turns south to historic Glen Ellen
, passing within one mile (1.6 kilometers) of Jack London State Historic Park
and the Wolf House and thence southward paralleling Arnold Drive. In the city of Sonoma
it is an urban
creek which emerges into agricultural areas to the south. Finally, Sonoma Creek discharges to the vast Napa-Sonoma Marsh at the northern tip of San Pablo Bay
. Principal tributaries to the creek include Yulupa Creek
, Graham Creek
, Calabazas Creek
, Bear Creek
, Schell Creek, and Fowler Creek.
, elevation 2750 feet (833 m) and Bald Mountain, elevation 2729 feet (826 m), each of which has views of the Pacific Ocean and the Sierra Nevada range. The headwaters cut through gorge and meadow of Sugarloaf Ridge State Park
, which boasts 25 miles (40 kilometers) of self-guided trail
s and the Robert Ferguson Observatory. There is also a 25 foot (eight meter) high waterfall, present only when fed by the winter rains but can persist until late May for high rainfall years such as 2006. In the 100 foot (30 m) deep gorge into which the waterfall spills is a moist mixed forest habitat including California bay laurel
, Coast redwood, Douglas fir, Big leaf maple, Cherry holly, Coffeeberry, and even Tanbark Oak. The understory features abundant fern
s and boulder laden moss
es. A prominent landform
in this upper reach created by Sonoma Creek is Adobe Canyon. Locally part of this upper reach flow is sometimes called Adobe Creek. Tributaries near the headwaters include Mount Hood Creek and Graywood Creek.
A diversity of aquatic
and terrestrial
organism
s populate Sonoma Creek and its riparian zone
. Winter-run Chinook salmon
(Oncorhynchus tsawytscha), Delta smelt
(Hypomesus transpacificus) and steelhead (Onchorhynchus mykiss) are the most prominent fish
es. Anadromous fish movements in Sonoma Creek have been studied extensively not only in the mainstem Sonoma Creek, but in some of the tributaries. These investigations have demonstrated a historical decline in spawning and habitat value for these species, primarily due to sedimentation
and secondarily to removal of riparian vegetation since the 1800s.
A variety of salamander
s, snake
s and frogs are also present. The federally listed as threatened California red-legged frog
is present in the northern reach draining the south slopes of Annadel State Park
. Several endangered species
(mostly associated with the marshy discharge area) present include California clapper rail
(Rallus longirostris), California Black Rail
(Laterallus jamaicensis), California brown pelican
(Pelicanus occudentalis), California freshwater shrimp (Syncaris pacifica
), Salt marsh harvest mouse
(Reithrodontomys raviventris ), Suisun Shrew
(Sorex ornatus sinuosus), Sacramento splittail (Pogonichtys macrolepidotus). The above are endangered species
with the exception of the splittail, steelhead and black rail, which species are federally designated as Threatened.
California Golden Beaver ("Castor canadensis subauratus") were historically abundant along Sonoma Creek but were trapped out in the California Fur Rush
of the late eighteenth and early nineteenth centuries. In 1828 fur trapper Michel La Framboise travelled from the Bonaventura River
to San Francisco and then the missions of San José, San Francisco Solano
and San Rafael Arcángel
. La Framboise stated that "the Bay of San
Francisco abounds in beaver", and that he "made his best hunt in the vicinity of the missions". The beaver were likely wiped out by the mid-nineteenth century but returned to Sonoma Creek, likely from the Delta, in the 1990s. In 1996 a beaver family developed a taste for merlot grapevine bark in a vineyard beside the creek and were exterminated, leading to civic uproar and a shift to accommodate beaver resettlement. Sonoma Ecology Center executive director Richard Dale reports that although beavers fell trees and dam culverts, on balance they perform nearly "perfect stream restoration," because they cause the creation of deep pools, slowing the flow of flood water and enhancing fishery habitat. New beavers have recolonized Sonoma Creek and are currently located in both Sonoma
and Glen Ellen
. A "keystone species
", the beaver have created habitat that has, in turn, led to the return of river otter ("Lontra canadensis") which have been sighted recently in the beaver pond below the Boyes Boulevard bridge in Boyes Hot Springs.
Upland ecosystems drained include mixed California oak woodland
, chaparral
and savannah
woodland
, In these upland reaches one finds plentiful Black-tailed Deer
, coyote
, skunk, raccoon, opossum, wild turkey
, turkey vulture
, red-tailed hawk
and occasionally bobcat and mountain lion. Prominent higher elevation trees include: Coast live oak
, Garry Oak
, Pacific madrone
, California Buckeye, Douglas fir, whereas Valley oak
is prevalent on the Sonoma Valley
floor.
and bank cutting were at sustainable levels and did not add enough turbidity
to the creek system to discourage aquatic species. Flooding in the downstream reaches did not realize the modern frequencies since all the creek
reaches could absorb more excess water from peak rainfall events. The Kenwood
area existed in the form of a large marsh effectively blocked by a natural earthen dam
from penetrating the course of the creek as it flows west out of Kenwood toward Glen Ellen
.
With the advent of more intensive farming of Sonoma Valley in the latter half of the nineteenth century, the Kenwood Marsh
was drained in favor of grazing
, vineyard
s and other agricultural
uses. This action removed the largest upstream buffer that assisted flood control in the lower reaches of Sonoma Creek. Consequently the frequency and severity of modern floods (1980s onward) has been exacerbated by these interventions of humans.
parameters in Sonoma Creek to be: turbidity
, pathogen
s and nitrate
s. Turbidity is an issue because of historical problems of erosion of stream banks, especially in the presence of ongoing land development in Sonoma Valley
. Increased sedimentation
has a variety of adverse impacts including direct harm to aquatic organisms and the more specific impact of altering streambed gravel
s to reduce productivity of spawning habitats; additionally sedimentation of pools decreases the efficacy of anadromous fish summering habitat by increasing critical summer water temperatures in these pools. Pathogens appear to be linked to septic tank
or leach field failures in some of the rural reaches, particularly in the upper valley sections. Nitrates enter the stream system from excess fertilizers applied to land uses in the drainage basin and may also be present in septic wastes improperly entering the creek. Sediment and nitrates may also enter the stream through urban stormwater
runoff
in the city of Sonoma reach.
Wine Country
, it is a vital resource for aquifer
recharge. Proportionally a greater percent of Sonoma Creek feeds recharge than its neighbors, the Napa
and Petaluma River
s. This outcome derives from the presence of pervious valley floor alluvial soils and the gentle stream gradients along the valley floor, where most of the reaches occur. The valley itself is part of the Franciscan Complex, which includes crumpled, uplifted terrane
s that have resulted from the subduction
of the former oceanic Farallon Plate
under the North American continent. The area is attended by volcanism
and sediments, deposited in the lagoons behind its island arc
s), which resulted from geological events dating from 140 to 42 million years. Recharge for the Sonoma Valley is critical because local rainfall is only about 29 inches (74 centimeters) per annum. Grape growing and wine
production require considerable groundwater
extraction. Some of the principal upper reach wineries
in Kenwood are Saint Francis Winery, Kunde Winery, Kenwood Winery, Chateau Saint Jean, Mayo Winery, Remick Ridge Vineyards
and VJB Winery. Wineries in the middle reach include: B.R. Cohn, Valley of the Moon Winery, Imagery and Sebastiani. In the lower reach one finds Gloria Ferrer, Carneros and Ravenswood wineries.
systems and encroachment by agriculture
and other forms of development. This Napa-Sonoma Marsh has been formed largely by sedimentary deposits over the last two million years. The basement depositional layer is the Alameda group. Higher are Old bay mud
and Young bay mud, between which there are intermediate deposits of the Alameda formation, which consists of alluvial and swamp
origins. The entire marsh area is considered subject to liquefaction
in the case of a major seismic event. The marsh
is subject to diurnal tidal variations of approximately 5.5 feet (1.7 m).
Historically the marsh supported an extremely diverse wetlands ecosystem
, with a variety of primary productivity plants including pickleweed
, eelgrass
and giant bulrush (Scirpus californiens). There has also been historically significant fish, mammal
, amphibian
and avafauna. The marsh is a significant element within the Pacific Flyway
providing resting and feeding areas for migratory
birds. As of 2006 this ecosystem has been significantly compromised by fill, levee
formation, dredging and other development; estimates generally state that 75 percent of the original biological productivity of the marsh has been destroyed. However, it remains a significant habitat and is subject to meaningful wetland
restoration
activity, that is being actively evaluated as of the 2000-2006 timeframe.
, hydrology modeling studies, stream conservation work, including erosion control and wildlife
conservation. Other current activities include considerable research in public and private sectors including work by the U.S. Army Corps of Engineers, Sonoma County and various private conservation groups.
Due to overpopulation
of Sonoma Valley
as well as overly intensive agriculture
, groundwater
supplies have been drawn down to the point of causing deleterious effects. The U.S. Geological Survey has found in the Carneros region between Sonoma Creek and the Napa Ridge that due to excessive groundwater drawdown, saltwater intrusion
is already occurring, rendering water unsuitable for many uses.
Stream
A stream is a body of water with a current, confined within a bed and stream banks. Depending on its locale or certain characteristics, a stream may be referred to as a branch, brook, beck, burn, creek, "crick", gill , kill, lick, rill, river, syke, bayou, rivulet, streamage, wash, run or...
in northern California
Northern California
Northern California is the northern portion of the U.S. state of California. The San Francisco Bay Area , and Sacramento as well as its metropolitan area are the main population centers...
. It is one of two principal drainages of southern Sonoma County, California
Sonoma County, California
Sonoma County, located on the northern coast of the U.S. state of California, is the largest and northernmost of the nine San Francisco Bay Area counties. Its population at the 2010 census was 483,878. Its largest city and county seat is Santa Rosa....
, with headwaters rising in the rugged hills of Sugarloaf Ridge State Park
Sugarloaf Ridge State Park
Sugarloaf Ridge State Park is a state park in Northern California, U.S.A.. Located in the Mayacamas Mountains north of Kenwood, the park straddles the boundary between Sonoma and Napa counties...
and discharging to San Pablo Bay
San Pablo Bay
San Pablo Bay is a tidal estuary that forms the northern extension of San Francisco Bay in northern California in the United States. Most of the Bay is shallow; however, there is a deep water channel approximately in mid bay, which allows access to Sacramento, Stockton, Benicia, Martinez, and...
, the northern arm of 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...
. The watershed drained by Sonoma Creek is roughly equivalent to the wine region of Sonoma Valley
Sonoma Valley
Sonoma Valley is the birthplace of the California wine industry and often called The Valley of the Moon. Sonoma Valley is home to some of the earliest vineyards and wineries in the state, some of which survived the phylloxera epidemic of the 1870s and the impact of Prohibition...
, an area of about 170 square miles (440.3 km²). The State of California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
has designated the Sonoma Creek watershed
Drainage basin
A drainage basin is an extent or an area of land where surface water from rain and melting snow or ice converges to a single point, usually the exit of the basin, where the waters join another waterbody, such as a river, lake, reservoir, estuary, wetland, sea, or ocean...
as a “Critical Coastal Water Resource”. To the east of this generally rectangular watershed is the Napa River
Napa River
The Napa River, approximately 55 miles long, is a river in the U.S. state of California. It drains a famous wine-growing region, called the Napa Valley, in the mountains northeast of San Francisco. Milliken Creek is a tributary of the Napa River....
watershed, and to the west are the Petaluma River
Petaluma River
The Petaluma River is a river in the California counties of Sonoma and Marin that becomes a tidal slough near its mouth. It springs from farmlands southwest of Cotati and flows generally southward through Petaluma's old town and of tidal marshes to end in northwest San Pablo Bay.-History:The word...
and Tolay Creek
Tolay Creek
Tolay Creek is a southward-flowing stream in southern Sonoma County, California, USA, which flows through Tolay Lake and ends in north San Pablo Bay.-History:The Alaguali were a Coast Miwok community of northern San Pablo Bay in the Tolay Creek region...
watersheds.
This south flowing river
River
A river is a natural watercourse, usually freshwater, flowing towards an ocean, a lake, a sea, or another river. In a few cases, a river simply flows into the ground or dries up completely before reaching another body of water. Small rivers may also be called by several other names, including...
drains the western slopes of the Mayacamas Range, the southern slopes of Annadel State Park
Annadel State Park
Annadel State Park is a state park of California, USA, situated at the northern edge of Sonoma Valley and offering many recreational activities within its property...
and the eastern slopes of the Sonoma Mountains
Sonoma Mountains
The Sonoma Mountains are a northwest-southeast trending formation of California Coast Ranges in Sonoma County, California, USA. The range is approximately fourteen miles long and separates the Sonoma Creek watershed from the Petaluma River and Tolay Creek watersheds...
with intermittent winter flows in the higher tributary reaches. As the tributaries and headwaters reach the valley floor, a perennial stream cuts through scenic and valuable vineyard
Vineyard
A vineyard is a plantation of grape-bearing vines, grown mainly for winemaking, but also raisins, table grapes and non-alcoholic grape juice...
s of Kenwood
Kenwood, California
Kenwood, California is an unincorporated town and census-designated place in Sonoma County, California, United States, located on Sonoma Highway between the cities Santa Rosa and Sonoma. It lies east of Sonoma Creek in the upper part of Sonoma Valley, a region sometimes called the Valley of the...
. Sonoma Creek veers west at Kenwood and cuts a gorge running parallel to Warm Springs Road, where it turns south to historic Glen Ellen
Glen Ellen, California
Glen Ellen is a census-designated place in Sonoma Valley, Sonoma County, California, USA. The population was 784 at the 2010 census, down from 992 at the 2000 census. Glen Ellen is the location of Jack London State Historic Park , Sonoma Valley Regional Park, and a former home of Hunter S....
, passing within one mile (1.6 kilometers) of Jack London State Historic Park
Jack London State Historic Park
Jack London State Historic Park, also known as Jack London Home and Ranch, is a California State Historic Park near Glen Ellen, California, United States, situated on the eastern slope of Sonoma Mountain...
and the Wolf House and thence southward paralleling Arnold Drive. In the city of Sonoma
Sonoma, California
Sonoma is a historically significant city in Sonoma Valley, Sonoma County, California, USA, surrounding its historic town plaza, a remnant of the town's Mexican colonial past. It was the capital of the short-lived California Republic...
it is an urban
Urban area
An urban area is characterized by higher population density and vast human features in comparison to areas surrounding it. Urban areas may be cities, towns or conurbations, but the term is not commonly extended to rural settlements such as villages and hamlets.Urban areas are created and further...
creek which emerges into agricultural areas to the south. Finally, Sonoma Creek discharges to the vast Napa-Sonoma Marsh at the northern tip of San Pablo Bay
San Pablo Bay
San Pablo Bay is a tidal estuary that forms the northern extension of San Francisco Bay in northern California in the United States. Most of the Bay is shallow; however, there is a deep water channel approximately in mid bay, which allows access to Sacramento, Stockton, Benicia, Martinez, and...
. Principal tributaries to the creek include Yulupa Creek
Yulupa Creek
Yulupa Creek is a southeast-flowing perennial stream that rises on the southeastern flanks of the northern Sonoma Mountains in Sonoma County, California, United States...
, Graham Creek
Graham Creek
Graham Creek is a perennial stream in Sonoma County, California, tributary to Sonoma Creek. Graham Creek rises in the northern Sonoma Mountains and flows generally northeasterly down the northeastern flank of Sonoma Mountain. Historically this watercourse was called Wild Water Creek, a name used...
, Calabazas Creek
Calabazas Creek
Calabazas Creek is a stream in the Sonoma Valley, California, USA, that rises in the southern Mayacamas Mountains and empties into Sonoma Creek near Glen Ellen.-History:...
, Bear Creek
Bear Creek (Sonoma Creek)
Bear Creek is a stream in eastern Sonoma County, California, United States, a tributary of Sonoma Creek.-Course:The stream originates near the Sonoma-Napa county line, about north of the northern Bald Mountain summit...
, Schell Creek, and Fowler Creek.
Headwaters
Headwaters rise on the west facing slopes of the inner coast southern Mayacamas Mountains, where the highest peaks are Hood MountainHood Mountain
Mount Hood, also known as Hood Mountain is a mountain near the southeastern edge of Santa Rosa, California at the northeast of the Sonoma Valley and attains a height of . The originally name was Mount Wilikos, an Indian name meaning "willows."...
, elevation 2750 feet (833 m) and Bald Mountain, elevation 2729 feet (826 m), each of which has views of the Pacific Ocean and the Sierra Nevada range. The headwaters cut through gorge and meadow of Sugarloaf Ridge State Park
Sugarloaf Ridge State Park
Sugarloaf Ridge State Park is a state park in Northern California, U.S.A.. Located in the Mayacamas Mountains north of Kenwood, the park straddles the boundary between Sonoma and Napa counties...
, which boasts 25 miles (40 kilometers) of self-guided trail
Trail
A trail is a path with a rough beaten or dirt/stone surface used for travel. Trails may be for use only by walkers and in some places are the main access route to remote settlements...
s and the Robert Ferguson Observatory. There is also a 25 foot (eight meter) high waterfall, present only when fed by the winter rains but can persist until late May for high rainfall years such as 2006. In the 100 foot (30 m) deep gorge into which the waterfall spills is a moist mixed forest habitat including California bay laurel
Bay Laurel
The bay laurel , also known as sweet bay, bay tree, true laurel, Grecian laurel, laurel tree, or simply laurel, is an aromatic evergreen tree or large shrub with green, glossy leaves, native to the Mediterranean region. It is the source of the bay leaf used in cooking...
, Coast redwood, Douglas fir, Big leaf maple, Cherry holly, Coffeeberry, and even Tanbark Oak. The understory features abundant fern
Fern
A fern is any one of a group of about 12,000 species of plants belonging to the botanical group known as Pteridophyta. Unlike mosses, they have xylem and phloem . They have stems, leaves, and roots like other vascular plants...
s and boulder laden moss
Moss
Mosses are small, soft plants that are typically 1–10 cm tall, though some species are much larger. They commonly grow close together in clumps or mats in damp or shady locations. They do not have flowers or seeds, and their simple leaves cover the thin wiry stems...
es. A prominent landform
Landform
A landform or physical feature in the earth sciences and geology sub-fields, comprises a geomorphological unit, and is largely defined by its surface form and location in the landscape, as part of the terrain, and as such, is typically an element of topography...
in this upper reach created by Sonoma Creek is Adobe Canyon. Locally part of this upper reach flow is sometimes called Adobe Creek. Tributaries near the headwaters include Mount Hood Creek and Graywood Creek.
Ecology
Aquatic ecosystem
An aquatic ecosystem is an ecosystem in a body of water. Communities of organisms that are dependent on each other and on their environment live in aquatic ecosystems. The two main types of aquatic ecosystems are marine ecosystems and freshwater ecosystems....
and terrestrial
Terrestrial animal
Terrestrial animals are animals that live predominantly or entirely on land , as compared with aquatic animals, which live predominantly or entirely in the water , or amphibians, which rely on a combination of aquatic and terrestrial habitats...
organism
Organism
In biology, an organism is any contiguous living system . In at least some form, all organisms are capable of response to stimuli, reproduction, growth and development, and maintenance of homoeostasis as a stable whole.An organism may either be unicellular or, as in the case of humans, comprise...
s populate Sonoma Creek and its riparian zone
Riparian zone
A riparian zone or riparian area is the interface between land and a river or stream. Riparian is also the proper nomenclature for one of the fifteen terrestrial biomes of the earth. Plant habitats and communities along the river margins and banks are called riparian vegetation, characterized by...
. Winter-run Chinook salmon
Chinook salmon
The Chinook salmon, Oncorhynchus tshawytscha, is the largest species in the pacific salmon family. Other commonly used names for the species include King salmon, Quinnat salmon, Spring salmon and Tyee salmon...
(Oncorhynchus tsawytscha), Delta smelt
Delta smelt
Delta smelt, Hypomesus transpacificus, is an endangered slender-bodied smelt, about long, of the Osmeridae family. Endemic to the upper Sacramento-San Joaquin estuary of California, it mainly inhabits the freshwater-saltwater mixing zone of the estuary, except during its spawning season, which...
(Hypomesus transpacificus) and steelhead (Onchorhynchus mykiss) are the most prominent fish
Fish
Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...
es. Anadromous fish movements in Sonoma Creek have been studied extensively not only in the mainstem Sonoma Creek, but in some of the tributaries. These investigations have demonstrated a historical decline in spawning and habitat value for these species, primarily due to sedimentation
Sedimentation
Sedimentation is the tendency for particles in suspension to settle out of the fluid in which they are entrained, and come to rest against a barrier. This is due to their motion through the fluid in response to the forces acting on them: these forces can be due to gravity, centrifugal acceleration...
and secondarily to removal of riparian vegetation since the 1800s.
A variety of salamander
Salamander
Salamander is a common name of approximately 500 species of amphibians. They are typically characterized by a superficially lizard-like appearance, with their slender bodies, short noses, and long tails. All known fossils and extinct species fall under the order Caudata, while sometimes the extant...
s, snake
Snake
Snakes are elongate, legless, carnivorous reptiles of the suborder Serpentes that can be distinguished from legless lizards by their lack of eyelids and external ears. Like all squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales...
s and frogs are also present. The federally listed as threatened California red-legged frog
California Red-legged Frog
The California red-legged frog, Rana draytonii, is a moderate to large species of frog. It is known under the scientific name Rana draytonii, after being long included with the northern red-legged frog The California red-legged frog, Rana draytonii, is a moderate to large (4.4–14 cm) species...
is present in the northern reach draining the south slopes of Annadel State Park
Annadel State Park
Annadel State Park is a state park of California, USA, situated at the northern edge of Sonoma Valley and offering many recreational activities within its property...
. Several endangered species
Endangered species
An endangered species is a population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters...
(mostly associated with the marshy discharge area) present include California clapper rail
California Clapper Rail
The California Clapper Rail is an endangered subspecies of the Clapper Rail . It is found principally in California's San Francisco Bay, and also in Monterey Bay and Morro Bay...
(Rallus longirostris), California Black Rail
Black Rail
The Black Rail is a mouse-sized member of the Rallidae family of birds. It is found in scattered parts of North America and the Pacific region of South America, usually in coastal salt marshes but also in some freshwater marshes. It is extinct or threatened in many locations due to habitat loss...
(Laterallus jamaicensis), California brown pelican
Brown Pelican
The Brown Pelican is the smallest of the eight species of pelican, although it is a large bird in nearly every other regard. It is in length, weighs from and has a wingspan from .-Range and habits:...
(Pelicanus occudentalis), California freshwater shrimp (Syncaris pacifica
Syncaris pacifica
Syncaris pacifica is an endangered species of freshwater shrimp in the family Atyidae that occurs only in a limited range within the northern San Francisco Bay Area, California, USA. Specifically, this species occurs only in 17 stream segments within Sonoma, Napa and Marin Counties...
), Salt marsh harvest mouse
Salt Marsh Harvest Mouse
The Salt Marsh Harvest Mouse , also known as the Red-bellied Harvest Mouse and some times called by Saltmarsh Harvest Mouse, is an endangered rodent endemic to the San Francisco Bay Area salt marshes in California. There are two distinct subspecies, both endangered and listed together on federal...
(Reithrodontomys raviventris ), Suisun Shrew
Suisun Shrew
Sorex ornatus sinuosus, the Suisun Shrew or Suisun ornate shrew, is a subspecies of the Ornate Shrew that occurs in the tidal marshes of the northern shores of San Pablo and Suisun bays Sorex ornatus sinuosus, the Suisun Shrew or Suisun ornate shrew, is a subspecies of the Ornate Shrew that occurs...
(Sorex ornatus sinuosus), Sacramento splittail (Pogonichtys macrolepidotus). The above are endangered species
Endangered species
An endangered species is a population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters...
with the exception of the splittail, steelhead and black rail, which species are federally designated as Threatened.
California Golden Beaver ("Castor canadensis subauratus") were historically abundant along Sonoma Creek but were trapped out in the California Fur Rush
California Fur Rush
Before the 1849 California Gold Rush, American, English and Russian fur hunters were drawn to Spanish California in a California Fur Rush, to exploit its enormous fur resources...
of the late eighteenth and early nineteenth centuries. In 1828 fur trapper Michel La Framboise travelled from the Bonaventura River
Sacramento River
The Sacramento River is an important watercourse of Northern and Central California in the United States. The largest river in California, it rises on the eastern slopes of the Klamath Mountains, and after a journey south of over , empties into Suisun Bay, an arm of the San Francisco Bay, and...
to San Francisco and then the missions of San José, San Francisco Solano
Mission San Francisco Solano
Mission San Francisco Solano was founded on July 4, 1823, and named for Francis Solanus, a missionary to the Indians of Peru born in Montilla, Spain, known as the "Wonder Worker of the New World." Originally planned as an asistencia to Mission San Rafael Arcángel, it is the northernmost Alta...
and San Rafael Arcángel
Mission San Rafael Arcángel
Mission San Rafael Arcángel was founded in 1817 as a medical asistencia of the Mission San Francisco de Asís as a hospital to treat sick Native Americans of the Bay Area, making it Alta California's first sanitarium. The weather was much better in the North Bay than in San Francisco, and helped...
. La Framboise stated that "the Bay of San
Francisco abounds in beaver", and that he "made his best hunt in the vicinity of the missions". The beaver were likely wiped out by the mid-nineteenth century but returned to Sonoma Creek, likely from the Delta, in the 1990s. In 1996 a beaver family developed a taste for merlot grapevine bark in a vineyard beside the creek and were exterminated, leading to civic uproar and a shift to accommodate beaver resettlement. Sonoma Ecology Center executive director Richard Dale reports that although beavers fell trees and dam culverts, on balance they perform nearly "perfect stream restoration," because they cause the creation of deep pools, slowing the flow of flood water and enhancing fishery habitat. New beavers have recolonized Sonoma Creek and are currently located in both Sonoma
Sonoma, California
Sonoma is a historically significant city in Sonoma Valley, Sonoma County, California, USA, surrounding its historic town plaza, a remnant of the town's Mexican colonial past. It was the capital of the short-lived California Republic...
and Glen Ellen
Glen Ellen, California
Glen Ellen is a census-designated place in Sonoma Valley, Sonoma County, California, USA. The population was 784 at the 2010 census, down from 992 at the 2000 census. Glen Ellen is the location of Jack London State Historic Park , Sonoma Valley Regional Park, and a former home of Hunter S....
. A "keystone species
Keystone species
A keystone species is a species that has a disproportionately large effect on its environment relative to its abundance. Such species play a critical role in maintaining the structure of an ecological community, affecting many other organisms in an ecosystem and helping to determine the types and...
", the beaver have created habitat that has, in turn, led to the return of river otter ("Lontra canadensis") which have been sighted recently in the beaver pond below the Boyes Boulevard bridge in Boyes Hot Springs.
Upland ecosystems drained include mixed California oak woodland
California oak woodland
California oak woodland is a plant community found throughout the California chaparral and woodlands ecoregion of California in the United States and northwestern Baja California in Mexico...
, chaparral
Chaparral
Chaparral is a shrubland or heathland plant community found primarily in the U.S. state of California and in the northern portion of the Baja California peninsula, Mexico...
and savannah
Savannah
Savannah or savanna is a type of grassland.It can also mean:-People:* Savannah King, a Canadian freestyle swimmer* Savannah Outen, a singer who gained popularity on You Tube...
woodland
Woodland
Ecologically, a woodland is a low-density forest forming open habitats with plenty of sunlight and limited shade. Woodlands may support an understory of shrubs and herbaceous plants including grasses. Woodland may form a transition to shrubland under drier conditions or during early stages of...
, In these upland reaches one finds plentiful Black-tailed Deer
Black-tailed Deer
Two forms of black-tailed deer or blacktail deer occupying coastal temperate rainforest on North America's Pacific coast are subspecies of the mule deer. They have sometimes been treated as a species, but virtually all recent authorities maintain they are subspecies...
, coyote
Coyote
The coyote , also known as the American jackal or the prairie wolf, is a species of canine found throughout North and Central America, ranging from Panama in the south, north through Mexico, the United States and Canada...
, skunk, raccoon, opossum, wild turkey
Wild Turkey
The Wild Turkey is native to North America and is the heaviest member of the Galliformes. It is the same species as the domestic turkey, which derives from the South Mexican subspecies of wild turkey .Adult wild turkeys have long reddish-yellow to grayish-green...
, turkey vulture
Turkey Vulture
The Turkey Vulture is a bird found throughout most of the Americas. It is also known in some North American regions as the Turkey Buzzard , and in some areas of the Caribbean as the John Crow or Carrion Crow...
, red-tailed hawk
Red-tailed Hawk
The Red-tailed Hawk is a bird of prey, one of three species colloquially known in the United States as the "chickenhawk," though it rarely preys on standard sized chickens. It breeds throughout most of North America, from western Alaska and northern Canada to as far south as Panama and the West...
and occasionally bobcat and mountain lion. Prominent higher elevation trees include: Coast live oak
Coast Live Oak
Quercus agrifolia, the Coast Live Oak, is an evergreen oak , native to the California Floristic Province. It grows west of the Sierra Nevada from Mendocino County, California, south to northern Baja California in Mexico. It is classified in the red oak section Quercus agrifolia, the Coast Live Oak,...
, Garry Oak
Garry Oak
Quercus garryana, the Garry Oak, Oregon White Oak or Oregon Oak, has a range from southern California to extreme southwestern British Columbia, particularly southeastern Vancouver Island and the adjacent Gulf Islands. It grows from sea level to 210 m altitude in the northern part of its range, and...
, Pacific madrone
Pacific Madrone
Arbutus menziesii, commonly known as the Pacific Madrone, is a species of Arbutus found on the west coast of North America, from British Columbia to California...
, California Buckeye, Douglas fir, whereas Valley oak
Valley Oak
Quercus lobata, commonly called the Valley oak, grows into the largest of North American oaks. It is endemic to California, growing in the interior valleys and foothills. Mature specimens may attain an age of up to 600 years. This deciduous oak requires year-round access to groundwater.Its thick,...
is prevalent on the Sonoma Valley
Sonoma Valley
Sonoma Valley is the birthplace of the California wine industry and often called The Valley of the Moon. Sonoma Valley is home to some of the earliest vineyards and wineries in the state, some of which survived the phylloxera epidemic of the 1870s and the impact of Prohibition...
floor.
History of the creek
Up until about 1850 Sonoma Creek operated in a virtual prehistoric fashion. Adverse erosionErosion
Erosion is when materials are removed from the surface and changed into something else. It only works by hydraulic actions and transport of solids in the natural environment, and leads to the deposition of these materials elsewhere...
and bank cutting were at sustainable levels and did not add enough turbidity
Turbidity
Turbidity is the cloudiness or haziness of a fluid caused by individual particles that are generally invisible to the naked eye, similar to smoke in air. The measurement of turbidity is a key test of water quality....
to the creek system to discourage aquatic species. Flooding in the downstream reaches did not realize the modern frequencies since all the creek
Stream
A stream is a body of water with a current, confined within a bed and stream banks. Depending on its locale or certain characteristics, a stream may be referred to as a branch, brook, beck, burn, creek, "crick", gill , kill, lick, rill, river, syke, bayou, rivulet, streamage, wash, run or...
reaches could absorb more excess water from peak rainfall events. The Kenwood
Kenwood, California
Kenwood, California is an unincorporated town and census-designated place in Sonoma County, California, United States, located on Sonoma Highway between the cities Santa Rosa and Sonoma. It lies east of Sonoma Creek in the upper part of Sonoma Valley, a region sometimes called the Valley of the...
area existed in the form of a large marsh effectively blocked by a natural earthen dam
Dam
A dam is a barrier that impounds water or underground streams. Dams generally serve the primary purpose of retaining water, while other structures such as floodgates or levees are used to manage or prevent water flow into specific land regions. Hydropower and pumped-storage hydroelectricity are...
from penetrating the course of the creek as it flows west out of Kenwood toward Glen Ellen
Glen Ellen, California
Glen Ellen is a census-designated place in Sonoma Valley, Sonoma County, California, USA. The population was 784 at the 2010 census, down from 992 at the 2000 census. Glen Ellen is the location of Jack London State Historic Park , Sonoma Valley Regional Park, and a former home of Hunter S....
.
With the advent of more intensive farming of Sonoma Valley in the latter half of the nineteenth century, the Kenwood Marsh
Marsh
In geography, a marsh, or morass, is a type of wetland that is subject to frequent or continuous flood. Typically the water is shallow and features grasses, rushes, reeds, typhas, sedges, other herbaceous plants, and moss....
was drained in favor of grazing
Grazing
Grazing generally describes a type of feeding, in which a herbivore feeds on plants , and also on other multicellular autotrophs...
, vineyard
Vineyard
A vineyard is a plantation of grape-bearing vines, grown mainly for winemaking, but also raisins, table grapes and non-alcoholic grape juice...
s and other agricultural
Agriculture
Agriculture is the cultivation of animals, plants, fungi and other life forms for food, fiber, and other products used to sustain life. Agriculture was the key implement in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that nurtured the...
uses. This action removed the largest upstream buffer that assisted flood control in the lower reaches of Sonoma Creek. Consequently the frequency and severity of modern floods (1980s onward) has been exacerbated by these interventions of humans.
Water quality
The State of California Regional Water Quality Control Board considers the most significant water qualityWater quality
Water quality is the physical, chemical and biological characteristics of water. It is a measure of the condition of water relative to the requirements of one or more biotic species and or to any human need or purpose. It is most frequently used by reference to a set of standards against which...
parameters in Sonoma Creek to be: turbidity
Turbidity
Turbidity is the cloudiness or haziness of a fluid caused by individual particles that are generally invisible to the naked eye, similar to smoke in air. The measurement of turbidity is a key test of water quality....
, pathogen
Pathogen
A pathogen gignomai "I give birth to") or infectious agent — colloquially, a germ — is a microbe or microorganism such as a virus, bacterium, prion, or fungus that causes disease in its animal or plant host...
s and nitrate
Nitrate
The nitrate ion is a polyatomic ion with the molecular formula NO and a molecular mass of 62.0049 g/mol. It is the conjugate base of nitric acid, consisting of one central nitrogen atom surrounded by three identically-bonded oxygen atoms in a trigonal planar arrangement. The nitrate ion carries a...
s. Turbidity is an issue because of historical problems of erosion of stream banks, especially in the presence of ongoing land development in Sonoma Valley
Sonoma Valley
Sonoma Valley is the birthplace of the California wine industry and often called The Valley of the Moon. Sonoma Valley is home to some of the earliest vineyards and wineries in the state, some of which survived the phylloxera epidemic of the 1870s and the impact of Prohibition...
. Increased sedimentation
Sedimentation
Sedimentation is the tendency for particles in suspension to settle out of the fluid in which they are entrained, and come to rest against a barrier. This is due to their motion through the fluid in response to the forces acting on them: these forces can be due to gravity, centrifugal acceleration...
has a variety of adverse impacts including direct harm to aquatic organisms and the more specific impact of altering streambed gravel
Gravel
Gravel is composed of unconsolidated rock fragments that have a general particle size range and include size classes from granule- to boulder-sized fragments. Gravel can be sub-categorized into granule and cobble...
s to reduce productivity of spawning habitats; additionally sedimentation of pools decreases the efficacy of anadromous fish summering habitat by increasing critical summer water temperatures in these pools. Pathogens appear to be linked to septic tank
Septic tank
A septic tank is a key component of the septic system, a small-scale sewage treatment system common in areas with no connection to main sewage pipes provided by local governments or private corporations...
or leach field failures in some of the rural reaches, particularly in the upper valley sections. Nitrates enter the stream system from excess fertilizers applied to land uses in the drainage basin and may also be present in septic wastes improperly entering the creek. Sediment and nitrates may also enter the stream through urban stormwater
Stormwater
Stormwater is water that originates during precipitation events. It may also be used to apply to water that originates with snowmelt that enters the stormwater system...
runoff
Surface runoff
Surface runoff is the water flow that occurs when soil is infiltrated to full capacity and excess water from rain, meltwater, or other sources flows over the land. This is a major component of the water cycle. Runoff that occurs on surfaces before reaching a channel is also called a nonpoint source...
in the city of Sonoma reach.
Wine production
Because Sonoma Creek is the sole drainage flow of the Sonoma ValleySonoma Valley
Sonoma Valley is the birthplace of the California wine industry and often called The Valley of the Moon. Sonoma Valley is home to some of the earliest vineyards and wineries in the state, some of which survived the phylloxera epidemic of the 1870s and the impact of Prohibition...
Wine Country
Wine Country
The Wine Country is a region of Northern California in the United States known worldwide as a premium wine-growing region. Viticulture and wine-making have been practiced in the region since the mid-19th century...
, it is a vital resource for aquifer
Aquifer
An aquifer is a wet underground layer of water-bearing permeable rock or unconsolidated materials from which groundwater can be usefully extracted using a water well. The study of water flow in aquifers and the characterization of aquifers is called hydrogeology...
recharge. Proportionally a greater percent of Sonoma Creek feeds recharge than its neighbors, the Napa
Napa River
The Napa River, approximately 55 miles long, is a river in the U.S. state of California. It drains a famous wine-growing region, called the Napa Valley, in the mountains northeast of San Francisco. Milliken Creek is a tributary of the Napa River....
and Petaluma River
Petaluma River
The Petaluma River is a river in the California counties of Sonoma and Marin that becomes a tidal slough near its mouth. It springs from farmlands southwest of Cotati and flows generally southward through Petaluma's old town and of tidal marshes to end in northwest San Pablo Bay.-History:The word...
s. This outcome derives from the presence of pervious valley floor alluvial soils and the gentle stream gradients along the valley floor, where most of the reaches occur. The valley itself is part of the Franciscan Complex, which includes crumpled, uplifted terrane
Terrane
A terrane in geology is short-hand term for a tectonostratigraphic terrane, which is a fragment of crustal material formed on, or broken off from, one tectonic plate and accreted or "sutured" to crust lying on another plate...
s that have resulted from the subduction
Subduction
In geology, subduction is the process that takes place at convergent boundaries by which one tectonic plate moves under another tectonic plate, sinking into the Earth's mantle, as the plates converge. These 3D regions of mantle downwellings are known as "Subduction Zones"...
of the former oceanic Farallon Plate
Farallon Plate
The Farallon Plate was an ancient oceanic plate, which began subducting under the west coast of the North American Plate— then located in modern Utah— as Pangaea broke apart during the Jurassic Period...
under the North American continent. The area is attended by volcanism
Volcanism
Volcanism is the phenomenon connected with volcanoes and volcanic activity. It includes all phenomena resulting from and causing magma within the crust or mantle of a planet to rise through the crust and form volcanic rocks on the surface....
and sediments, deposited in the lagoons behind its island arc
Island arc
An island arc is a type of archipelago composed of a chain of volcanoes which alignment is arc-shaped, and which are situated parallel and close to a boundary between two converging tectonic plates....
s), which resulted from geological events dating from 140 to 42 million years. Recharge for the Sonoma Valley is critical because local rainfall is only about 29 inches (74 centimeters) per annum. Grape growing and wine
Wine
Wine is an alcoholic beverage, made of fermented fruit juice, usually from grapes. The natural chemical balance of grapes lets them ferment without the addition of sugars, acids, enzymes, or other nutrients. Grape wine is produced by fermenting crushed grapes using various types of yeast. Yeast...
production require considerable groundwater
Groundwater
Groundwater is water located beneath the ground surface in soil pore spaces and in the fractures of rock formations. A unit of rock or an unconsolidated deposit is called an aquifer when it can yield a usable quantity of water. The depth at which soil pore spaces or fractures and voids in rock...
extraction. Some of the principal upper reach wineries
Winery
A winery is a building or property that produces wine, or a business involved in the production of wine, such as a wine company. Some wine companies own many wineries. Besides wine making equipment, larger wineries may also feature warehouses, bottling lines, laboratories, and large expanses of...
in Kenwood are Saint Francis Winery, Kunde Winery, Kenwood Winery, Chateau Saint Jean, Mayo Winery, Remick Ridge Vineyards
Remick Ridge Vineyards
Remick Ridge Vineyards is a California-based vineyard and winery owned and operated by the Smothers Brothers. The setting of this viticulture operation is in the Sonoma Valley on a ridge of the northern Sonoma Mountains above Sonoma Creek...
and VJB Winery. Wineries in the middle reach include: B.R. Cohn, Valley of the Moon Winery, Imagery and Sebastiani. In the lower reach one finds Gloria Ferrer, Carneros and Ravenswood wineries.
Discharge to San Pablo Bay
This large marsh area has been reduced considerably from its historic dimensions due to construction of multiple leveeLevee
A levee, levée, dike , embankment, floodbank or stopbank is an elongated naturally occurring ridge or artificially constructed fill or wall, which regulates water levels...
systems and encroachment by agriculture
Agriculture
Agriculture is the cultivation of animals, plants, fungi and other life forms for food, fiber, and other products used to sustain life. Agriculture was the key implement in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that nurtured the...
and other forms of development. This Napa-Sonoma Marsh has been formed largely by sedimentary deposits over the last two million years. The basement depositional layer is the Alameda group. Higher are Old bay mud
Bay mud
Bay mud consists of thick deposits of soft, unconsolidated silty clay, which is saturated with water; these soil layers are situated at the bottom of certain estuaries, which are normally in temperate regions that have experienced cyclical glacial cycles...
and Young bay mud, between which there are intermediate deposits of the Alameda formation, which consists of alluvial and swamp
Swamp
A swamp is a wetland with some flooding of large areas of land by shallow bodies of water. A swamp generally has a large number of hammocks, or dry-land protrusions, covered by aquatic vegetation, or vegetation that tolerates periodical inundation. The two main types of swamp are "true" or swamp...
origins. The entire marsh area is considered subject to liquefaction
Liquefaction
Liquefaction may refer to:* Liquefaction, the general process of becoming liquid* Soil liquefaction, the process by which sediments become suspended* Liquefaction of gases in physics, chemistry, and thermal engineering* Liquefactive necrosis in pathology...
in the case of a major seismic event. The marsh
Marsh
In geography, a marsh, or morass, is a type of wetland that is subject to frequent or continuous flood. Typically the water is shallow and features grasses, rushes, reeds, typhas, sedges, other herbaceous plants, and moss....
is subject to diurnal tidal variations of approximately 5.5 feet (1.7 m).
Historically the marsh supported an extremely diverse wetlands ecosystem
Ecosystem
An ecosystem is a biological environment consisting of all the organisms living in a particular area, as well as all the nonliving , physical components of the environment with which the organisms interact, such as air, soil, water and sunlight....
, with a variety of primary productivity plants including pickleweed
Pickleweed
Pickleweed is a common name used for two unrelated genera of flowering plants:*Batis, family Bataceae*Salicornia, family Amaranthaceae...
, eelgrass
Zostera
Zostera is a small genus of widely distributed seagrass, commonly called marine eelgrass or simply eelgrass . The genus Zostera contains sixteen species.-Ecology:Zostera is found on sandy substrates or in estuaries submerged or partially floating...
and giant bulrush (Scirpus californiens). There has also been historically significant fish, mammal
Mammal
Mammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...
, amphibian
Amphibian
Amphibians , are a class of vertebrate animals including animals such as toads, frogs, caecilians, and salamanders. They are characterized as non-amniote ectothermic tetrapods...
and avafauna. The marsh is a significant element within the Pacific Flyway
Pacific Flyway
The Pacific Flyway is a major north-south route of travel for migratory birds in America, extending from Alaska to Patagonia. Every year, migratory birds travel some or all of this distance both in spring and in fall, following food sources, heading to breeding grounds, or travelling to...
providing resting and feeding areas for migratory
Bird migration
Bird migration is the regular seasonal journey undertaken by many species of birds. Bird movements include those made in response to changes in food availability, habitat or weather. Sometimes, journeys are not termed "true migration" because they are irregular or in only one direction...
birds. As of 2006 this ecosystem has been significantly compromised by fill, levee
Levee
A levee, levée, dike , embankment, floodbank or stopbank is an elongated naturally occurring ridge or artificially constructed fill or wall, which regulates water levels...
formation, dredging and other development; estimates generally state that 75 percent of the original biological productivity of the marsh has been destroyed. However, it remains a significant habitat and is subject to meaningful wetland
Wetland
A wetland is an area of land whose soil is saturated with water either permanently or seasonally. Wetlands are categorised by their characteristic vegetation, which is adapted to these unique soil conditions....
restoration
Restoration ecology
-Definition:Restoration ecology is the scientific study and practice of renewing and restoring degraded, damaged, or destroyed ecosystems and habitats in the environment by active human intervention and action, within a short time frame...
activity, that is being actively evaluated as of the 2000-2006 timeframe.
Recent developments
Because of the recognition of impacts of land development and land use practices, which began in the mid-19th century and have continued until 2006, certain actions are being considered by the Board of Supervisors of Sonoma County. Most notably a special parcel tax may be submitted to voters to assess landowners adjacent to Sonoma Creek. These funds could be used in flood controlFlood control
In communications, flood control is a feature of many communication protocols designed to prevent overwhelming of a destination receiver. Such controls can be implemented either in software or in hardware, and will often request that the message be resent after the receiver has finished...
, hydrology modeling studies, stream conservation work, including erosion control and wildlife
Wildlife
Wildlife includes all non-domesticated plants, animals and other organisms. Domesticating wild plant and animal species for human benefit has occurred many times all over the planet, and has a major impact on the environment, both positive and negative....
conservation. Other current activities include considerable research in public and private sectors including work by the U.S. Army Corps of Engineers, Sonoma County and various private conservation groups.
Due to overpopulation
Overpopulation
Overpopulation is a condition where an organism's numbers exceed the carrying capacity of its habitat. The term often refers to the relationship between the human population and its environment, the Earth...
of Sonoma Valley
Sonoma Valley
Sonoma Valley is the birthplace of the California wine industry and often called The Valley of the Moon. Sonoma Valley is home to some of the earliest vineyards and wineries in the state, some of which survived the phylloxera epidemic of the 1870s and the impact of Prohibition...
as well as overly intensive agriculture
Agriculture
Agriculture is the cultivation of animals, plants, fungi and other life forms for food, fiber, and other products used to sustain life. Agriculture was the key implement in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that nurtured the...
, groundwater
Groundwater
Groundwater is water located beneath the ground surface in soil pore spaces and in the fractures of rock formations. A unit of rock or an unconsolidated deposit is called an aquifer when it can yield a usable quantity of water. The depth at which soil pore spaces or fractures and voids in rock...
supplies have been drawn down to the point of causing deleterious effects. The U.S. Geological Survey has found in the Carneros region between Sonoma Creek and the Napa Ridge that due to excessive groundwater drawdown, saltwater intrusion
Saltwater intrusion
Saltwater intrusion is the movement of saline water into freshwater aquifers. Most often, it is caused by ground-water pumping from coastal wells, or from construction of navigation channels or oil field canals. The channels and canals provide conduits for salt water to be brought into fresh...
is already occurring, rendering water unsuitable for many uses.
See also
- California slender salamanderCalifornia slender salamanderThe California slender salamander is a lungless salamander that is found primarily in coastal mountain areas of Northern California, United States as well as in a limited part of the western foothills of the Sierra Nevada, California, in patches of the northern Central Valley of California, and in...
- List of rivers in California
- List of watercourses in the San Francisco Bay Area