San Francisco Bay is a large tidal estuary in the U.S. state of California, and gives its name to the San Francisco Bay Area. It is dominated by the cities of San Francisco, San Jose, and Oakland.
San Francisco Bay | |
---|---|
San Francisco Bay | |
Coordinates | 37°40′N 122°16′W / 37.67°N 122.27°W |
Type | Bay |
River sources | Sacramento River San Joaquin River Petaluma River Napa River Guadalupe River |
Ocean/sea sources | Pacific Ocean |
Basin countries | United States |
Max. length | 97 km (60 mi) |
Max. width | 19 km (12 mi) |
Surface area | 400–1,600 sq mi (1,000–4,100 km2) |
Average depth | 12–15 ft (3.7–4.6 m) |
Max. depth | 372 ft (113 m) |
Settlements | San Francisco San Jose Oakland |
Ramsar Wetland | |
Official name | San Francisco Bay/Estuary (SFBE) |
Designated | February 2, 2013 |
Reference no. | 2097 |
San Francisco Bay drains water from approximately 40 percent of California. Water from the Sacramento and San Joaquin rivers, and from the Sierra Nevada mountains, flow into Suisun Bay, which then travels through the Carquinez Strait to meet with the Napa River at the entrance to San Pablo Bay, which connects at its south end to San Francisco Bay. It then connects to the Pacific Ocean via the Golden Gate strait. However, this entire group of interconnected bays is often called the San Francisco Bay. The bay was designated a Ramsar Wetland of International Importance on February 2, 2013, and the Port of Oakland on the bay is one of the busiest cargo ports on the west coast.
Size
The bay covers somewhere between 400 and 1,600 square miles (1,000–4,000 km2), depending on which sub-bays (such as San Pablo Bay), estuaries, wetlands, and so on are included in the measurement. The main part of the bay measures three to twelve miles (5–19 km) wide east-to-west and somewhere between 48 miles (77 km)1 and 60 miles (97 km)2 north-to-south.
San Francisco Bay is the second-largest estuary on the Pacific coast of the Americas, following the Salish Sea in Washington State and British Columbia, Canada.
The bay was navigable as far south as San Jose until the 1850s, when hydraulic mining released massive amounts of sediment from the rivers that settled in those parts of the bay that had little or no current. Later, wetlands and inlets were deliberately filled in, reducing the bay's size since the mid-19th century by as much as one third. Recently, large areas of wetlands have been restored, further confusing the issue of the bay's size. Despite its value as a waterway and harbor, many thousands of acres of marshy wetlands at the edges of the bay were, for many years, considered wasted space. As a result, soil excavated for building projects or dredged from channels was often dumped onto the wetlands and other parts of the bay as landfill.[citation needed]
From the mid-19th century through the late 20th century, more than a third of the original bay was filled and often built on. The deep, damp soil in these areas is subject to soil liquefaction during earthquakes, and most of the major damage close to the bay in the Loma Prieta earthquake of 1989 occurred to structures on these areas.[citation needed]
The Marina District of San Francisco, hard hit by the 1989 earthquake, was built on fill that had been placed there for the Panama-Pacific International Exposition, although liquefaction did not occur on a large scale. In the 1990s, San Francisco International Airport proposed filling in hundreds more acres to extend its overcrowded international runways in exchange for purchasing other parts of the bay and converting them back to wetlands. The idea was, and remains, controversial. (For further details, see the "Bay fill and depth profile" section.)
There are five large islands in San Francisco Bay. Alameda, the largest island, was created when a shipping lane was cut to form the Port of Oakland in 1901. It is now a suburban community. Angel Island was known as "Ellis Island West" because it served as the entry point for immigrants from East Asia. It is now a state park accessible by ferry. Mountainous Yerba Buena Island is pierced by a tunnel linking the east and west spans of the San Francisco–Oakland Bay Bridge. Attached to the north is the artificial and flat Treasure Island, site of the 1939 Golden Gate International Exposition. From the Second World War until the 1990s, both islands served as military bases and are now being redeveloped. Isolated in the center of the bay is Alcatraz, the site of the famous federal penitentiary. The federal prison on Alcatraz Island no longer functions, but the complex is a popular tourist site. Despite its name, Mare Island in the northern part of the bay is a peninsula rather than an island.
Geology
San Francisco Bay is thought to represent a down-warping of the Earth's crust between the San Andreas Fault to the west and the Hayward Fault to the east, though the precise nature of this remains under study. About 560,000 years ago, a tectonic shift caused the large inland Lake Corcoran to spill out the central valley and through the Carquinez Strait, carving out sediment and forming canyons in what is now the northern part of the San Francisco Bay and Golden Gate strait.
San Francisco Bay has been filled and emptied of sea water many times during the Pleistocene in accordance with sea level changes caused by glacial advances and retreats. During the Wisconsin Glaciation, between 15,000 and about 10,000 years ago, the basin which is now filled by the San Francisco Bay was a large river valley with small hills, channeling the Sacramento River through the Golden Gate Strait into the ocean. When the great ice sheets began to melt, around 11,000 years ago, the sea level started to rise rapidly, by about 1 inch per year. Melting glaciers in the Sierra Nevada washed huge amounts of sediment down the Sacramento and San Joaquin rivers, which accumulated on the shores of the bay, forming huge mudflats and marshes that supported local wildlife. By 5000 BC the sea level rose 300 feet (90 m), filling the valley with water from the Pacific. The Farallon Islands are what used to be hills along the old coastline, and Potato Patch Shoal is an area of sand dunes now covered by the ocean.
History
The indigenous inhabitants of the San Francisco Bay are Ohlone. The first European to see San Francisco Bay is likely N. de Morena who was left at New Albion at Drakes Bay in Marin County, California, by Sir Francis Drake in 1579 and then walked to Mexico.
The first recorded European discovery of San Francisco Bay was on November 4, 1769, when Spanish explorer Gaspar de Portolá, unable to find the Port of Monterey, continued north close to what is now Pacifica and reached the summit of the 1,200-foot-high (370 m) Sweeney Ridge, now marked as the place where he first sighted San Francisco Bay. Portolá and his party did not realize what they had discovered, thinking they had arrived at a large arm of what is now called Drakes Bay. At the time, Drakes Bay went by the name Bahia de San Francisco and thus both bodies of water became associated with the name. Eventually, the larger, more important body of water fully appropriated the name San Francisco Bay.[citation needed]
The first European to enter the bay is believed to have been the Spanish explorer Juan de Ayala, who passed through the Golden Gate on August 5, 1775, in his ship the San Carlos and moored in a bay of Angel Island now known as Ayala Cove. Ayala continued to explore the San Francisco Bay Area and the expedition's cartographer, José de Cañizares, gathered the information necessary to produce the first map of the area. A number of place names survive (anglicized) from that first map, including Point Reyes, Angel Island, Farallon Islands, and Alcatraz Island.[citation needed]
Alaskan Native sea otter hunters using Aleutian kayaks and working for the Russian–American Company entered San Francisco Bay in 1807 and again over 1810–1811. Led by the Russian Timofei Nikitich Tarakanov, these hunting raids probably wiped out sea otters in the bay. Thousands of sea otter skins were taken to Sitka, then Guangzhou (Canton), China, where they commanded a high price.
The United States seized the region from Mexico during the Mexican–American War (1846–1848). On February 2, 1848, the Mexican province of Alta California was annexed to the United States with the signing of the Treaty of Guadalupe Hidalgo. A year and a half later, California requested to join the United States on December 3, 1849, and was accepted as the 31st State of the Union on September 9, 1850.[citation needed]
In 1921, a tablet was dedicated by a group of men in downtown San Francisco, marking the site of the original shoreline. The tablet reads: "This tablet marks the shore line of San Francisco Bay at the time of the discovery of gold in California, January 24, 1848. Map reproduced above delineates old shore line. Placed by the Historic Landmarks committee, Native Sons of the Golden West, 1921."
The bay became the center of American settlement and commerce in the Far West through most of the remainder of the 19th century. During the California Gold Rush (1848–1855), San Francisco Bay suddenly became one of the world's great seaports, dominating shipping in the American West until the last years of the 19th century. The bay's regional importance increased further when the first transcontinental railroad was connected to its western terminus at Alameda on September 6, 1869. The terminus was switched to the Oakland Long Wharf two months later on November 8, 1869.
In 1910, the Southern Pacific railroad company built the Dumbarton Rail Bridge, the first bridge crossing San Francisco Bay. The first automobile crossing was the Dumbarton Bridge, completed in January 1927. More crossings were later constructed – the Carquinez Bridge in May 1927, the San Francisco–Oakland Bay Bridge in 1936, the Golden Gate Bridge in 1937, the Richmond–San Rafael Bridge in 1956, and the San Mateo–Hayward Bridge in 1967.
During the 20th century, the bay was subject to the 1940s Reber Plan, which would have filled in parts of the bay in order to increase industrial activity along the waterfront. In 1959, the United States Army Corps of Engineers released a report stating that if current infill trends continued, the bay would be as big as a shipping channel by 2020. This news led to the creation of the Save the Bay movement in 1960, which mobilized to stop the infill of wetlands as well as the bay itself, which had shrunk to two-thirds of its size in the century before 1961.
On September 17, 1965, the California State Legislature enacted the McAteer-Petris Act, which created the San Francisco Bay Conservation and Development Commission. Since then, the Commission has strictly regulated bay fill. Foster City, Redwood Shores, Paradise Cay, and Emeryville's western expansion were among the last developments along the bay shoreline before McAteer-Petris limited additional filling of the bay.
The San Francisco Bay continues to support some of the densest industrial production and urban settlement in the United States. The San Francisco Bay Area is the American West's second-largest urban area, with approximately seven million residents.
Ecology
Despite its urban and industrial character, San Francisco Bay and the Sacramento–San Joaquin River Delta remain perhaps California's most important ecological habitats. California's Dungeness crab, California halibut, and Pacific salmon fisheries rely on the bay as a nursery. The few remaining salt marshes now represent most of California's remaining salt marsh, supporting a number of endangered species and providing key ecosystem services such as filtering pollutants and sediments from the rivers. San Francisco Bay is recognized for protection by the California Bays and Estuaries Policy, with oversight provided by the San Francisco Estuary Partnership.
Most famously, the bay is a key link in the Pacific Flyway. Millions of waterfowl annually use the bay shallows as a refuge. Two endangered species of birds are found here: the California least tern and the Ridgway's Rail. Exposed bay muds provide important feeding areas for shorebirds, but underlying layers of bay mud pose geological hazards for structures near many parts of the bay perimeter. San Francisco Bay provided the nation's first wildlife refuge, Oakland's artificial Lake Merritt, constructed in the 1860s, and America's first urban National Wildlife Refuge, the Don Edwards San Francisco Bay National Wildlife Refuge (SFBNWR) in 1972. The bay is also plagued by non-native species.[citation needed]
Salt produced from San Francisco Bay is produced in salt evaporation ponds and is shipped throughout the Western United States to bakeries, canneries, fisheries, cheese makers and other food industries and used to de-ice winter highways, clean kidney dialysis machines, for animal nutrition, and in many industries. Many companies have produced salt in the bay, with the Leslie Salt Company the largest private land owner in the Bay Area in the 1940s.
Low-salinity salt ponds mirror the ecosystem of the bay, with fish and fish-eating birds in abundance. Mid-salinity ponds support dense populations of brine shrimp, which provide a rich food source for millions of shorebirds. Only salt-tolerant micro-algae survive in the high salinity ponds, and impart a deep red color to these ponds from the pigment within the algae protoplasm. The salt marsh harvest mouse is an endangered species endemic to the wetlands of the San Francisco Bay with a high salt tolerance. It needs native pickleweed, which is often displaced by invasive cordgrass, for its habitat.
The seasonal range of water temperature in the bay is from January's 53 °F (12 °C) to September's 60 °F (16 °C) when measured at Fort Point, which is near the southern end of the Golden Gate Bridge and at the entrance to San Francisco Bay.
For the first time in 65 years, Pacific Harbor Porpoise (Phocoena phocoena) returned to the bay in 2009. Golden Gate Cetacean Research, a non-profit organization focused on research on cetaceans, has developed a photo-identification database enabling the scientists to identify specific porpoise individuals and is trying to ascertain whether a healthier bay has brought their return. Pacific harbor porpoise range from Point Conception, California, to Alaska and across to the Kamchatka Peninsula and Japan. Recent genetic studies show that there is a local stock from San Francisco to the Russian River and that eastern Pacific coastal populations rarely migrate far, unlike western Atlantic Harbor porpoise.
The common bottlenose dolphin (Tursiops truncatus) has been extending its current range northwards from the Southern California Bight. The first coastal bottlenose dolphin in the Bay Area in recent times was spotted in 1983 off the San Mateo County coast in 1983. In 2001, bottlenose dolphins were first spotted east of the Golden Gate Bridge and confirmed by photographic evidence in 2007. Zooarcheological remains of bottlenose dolphins indicated that bottlenose dolphins inhabited San Francisco Bay in prehistoric times until at least 700 years before present, and dolphin skulls dredged from the bay suggest occasional visitors in historic times.
Pollution
San Francisco Bay faces many of the same water quality issues as other urban waterways in industrialized countries, or downstream of intensive agriculture. According to state water quality regulators, San Francisco Bay waters do not meet water quality standards for the following pollutants:
- DDT
- Mercury
- Selenium
- PCBs (Polychlorinated biphenyls)
- Dioxin compounds
- Furan Compounds
- Trash
- Diazinon
- Chlordane
- Dieldrin
Mercury
Industrial, mining, and other uses of mercury have resulted in a widespread distribution in the bay, with uptake in the bay's phytoplankton and contamination of its sportfish.
Oil spills
In January 1971, two Standard Oil tankers collided in the bay, creating an 800,000-U.S.-gallon (3,000,000-liter) oil spill disaster, which spurred environmental protection of the bay. In November 2007, a ship named COSCO Busan collided with the San Francisco–Oakland Bay Bridge and spilled over 58,000 U.S. gallons (220,000 liters) of bunker fuel, creating the largest oil spill in the region since 1996.
Nutrients
The bay also has some of the highest levels of dissolved inorganic nitrogen known from any coastal water body, mostly originating from treated wastewater from Publicly owned treatment works. In other bays, such nutrient levels would likely lead to eutrophication, but historically, the bay has had less harmful algal blooms than other water bodies with similar nutrient concentrations. Potential explanations have included the presence of intensive "top-down control" from grazing clams like Potamocorbula, high sediment supply limiting light availability for the algae, and intensive tidal mixing. The occurrence of an unprecedented harmful algal bloom of Heterosigma akashiwo in 2022, resulting in mass fish deaths and anoxia, suggests that the mechanisms of control on algal growth may be eroding.
PBDEs
The bay was once considered a hotspot for polybrominated diphenyl ether (PBDE) flame retardants used to make upholstered furniture and infant care items less flammable. PBDEs have been largely phased out and replaced with alternative phosphate flame retardants. A 2019 San Francisco Estuary Institute (SFEI) study assayed a wide range of these newer flame retardant chemicals in Bay waters, bivalve California mussels (Mytilus californianus), and harbor seals (Phoca vitulina) which haul out in Corkscrew Slough on Bair Island in San Mateo County, with phosphate flame retardant contaminants such as tris(1,3-dichloro-2-propyl)phosphate (TDCPP) and triphenyl phosphate (TPhP) found at levels comparable to thresholds for aquatic toxicity.
Emerging contaminants
Thousands of man-made chemicals are found in Bay water, sediment, and organisms. For many of these, there is little or no data on their impacts on the environment or human health, and they are not regulated by state or federal law. These are often referred to as "contaminants of emerging concern." The San Francisco Estuary Institute has studied these chemicals in the Bay since 2001. Scientists have identified the following most likely to have a negative impact on Bay wildlife:
- PFOS
- fipronil
- nonylphenols
- nonylphenol ethoxylates
Bay fill and depth profile
San Francisco Bay's profile changed dramatically in the late 19th century and again with the initiation of dredging by the US Army Corps of Engineers in the 20th century. Before about 1860, most bay shores (with the exception of rocky shores, such as those in Carquinez Strait; along Marin shoreline; Point Richmond; Golden Gate area) contained extensive wetlands that graded nearly invisibly from freshwater wetlands to salt marsh and then tidal mudflat. A deep channel ran through the center of the bay, following the ancient drowned river valley.[citation needed]
In the 1860s and continuing into the early 20th century, miners dumped staggering quantities of mud and gravel from hydraulic mining operations into the upper Sacramento and San Joaquin Rivers. GK Gilbert's estimates of debris total more than eight times the amount of rock and dirt moved during construction of the Panama Canal. This material flowed down the rivers, progressively eroding into finer and finer sediment, until it reached the bay system. Here some of it settled, eventually filling in Suisun Bay, San Pablo Bay, and San Francisco Bay, in decreasing order of severity.[citation needed]
By the end of the 19th century, these "slickens" had filled in much of the shallow bay flats, raising the entire bay profile. New marshes were created in some areas.[citation needed]
In the decades surrounding 1900, at the behest of local political officials and following Congressional orders, the U.S. Army Corps began dredging the Sacramento and San Joaquin Rivers and the deep channels of San Francisco Bay. This work has continued without interruption ever since. Some of the dredge spoils were initially dumped in the bay shallows (including helping to create Treasure Island on the former shoals to the north of Yerba Buena Island) and used to raise islands in the Sacramento-San Joaquin Delta. The net effect of dredging has been to maintain a narrow deep channel—deeper perhaps than the original bay channel—through a much shallower bay. At the same time, most of the marsh areas have been filled or blocked off from the bay by dikes.
Large ships transiting the bay must follow deep underwater channels that are maintained by frequent dredging as the average depth of the bay is only as deep as a swimming pool—approximately 12 to 15 ft (4–5 m). Between Hayward and San Mateo to San Jose it is 12 to 36 in (30–90 cm). The deepest part of the bay is under and out of the Golden Gate Bridge, at 372 ft (113 m).
In the late 1990s, a 12-year harbor-deepening project for the Port of Oakland began; it was largely completed by September 2009. Previously, the bay waters and harbor facilities only allowed for ships with a draft of 46 ft (14 m), but dredging activities undertaken by the United States Army Corps of Engineers in partnership with the Port of Oakland succeeded in providing access for vessels with a 50-foot (15 m) draft. Four dredging companies were employed in the US$432 million project, with $244 million paid for with federal funds and $188 million supplied by the Port of Oakland. Some six million cubic yards (160 million cubic feet; 4.6 million cubic meters) of mud from the dredging was deposited at the western edge of Middle Harbor Shoreline Park to become a 188-acre (0.294 sq mi; 0.76 km2) shallow-water wetlands habitat for marine and shore life. Further dredging followed in 2011, to maintain the navigation channel. This dredging enabled the arrival of the largest container ship ever to enter the San Francisco Bay, the MSC Fabiola. Bay pilots trained for the visit on a simulator at the California Maritime Academy for over a year. The ship arrived drawing less than its full draft of 50 feet 10 inches (15.5 m) because it held only three-quarters of a load after its stop in Long Beach.
Transportation
1. | Richmond-San Rafael Bridge |
---|---|
2. | Golden Gate Bridge |
3. | San Francisco-Oakland Bay Bridge |
4. | San Mateo-Hayward Bridge |
5. | Dumbarton Bridge |
6. | Carquinez Bridge |
7. | Benicia-Martinez Bridge |
8. | Antioch Bridge |
San Francisco Bay was traversed by watercraft before the arrival of Europeans. Indigenous peoples used canoes to fish and clam along the shoreline. Sailing ships enabled transportation between the bay and other parts of the world—and served as ferries and freighters within the bay and between the bay and inland ports, such as Sacramento and Stockton. These were gradually replaced by steam-powered vessels starting in the late 19th century. Several shipyards were established around the bay, augmented during wartime (e.g., the Kaiser Shipyards, Richmond Shipyards) near Richmond in 1940 for World War II for construction of mass-produced, assembly line Liberty and Victory cargo ships.[citation needed]
San Francisco Bay is spanned by nine bridges, eight of which carry cars.[citation needed]
- The Richmond–San Rafael Bridge on Interstate 580 (I-580) connects Marin and Contra Costa counties.
- The Golden Gate Bridge on U.S. Route 101/State Route 1 (US 101/SR 1) was the largest single span suspension bridge ever built at the time of its 1937 construction. It spans the Golden Gate, the strait between San Francisco and Marin County, and is the only bridge in the area not owned by the State of California.
- The San Francisco–Oakland Bay Bridge on I-80 connects Alameda and San Francisco counties.
- The San Mateo–Hayward Bridge on SR 92 connects Alameda and San Mateo counties.
- The Dumbarton Bridge on SR 84 connects Alameda and San Mateo counties.
- The Carquinez Bridge (including the Alfred Zampa Memorial Bridge) on I-80 connects Contra Costa and Solano counties.
- The Benicia Bridge on I-680 also connects Contra Costa and Solano counties.
- The Antioch Bridge on SR 160 connects Contra Costa and Sacramento counties.
- The Dumbarton Rail Bridge is an abandoned bridge that used to carry rail traffic.
The Transbay Tube, an underwater rail tunnel, carries BART services between Oakland and San Francisco.[citation needed]
Prior to the bridges and, later, the Transbay Tube, transbay transportation was dominated by fleets of ferryboats operated by the Southern Pacific Railroad and the Key System transit company. However, in recent decades, ferries have returned, primarily serving commuters from Marin County, relieving the traffic bottleneck of the Golden Gate Bridge (see Ferries of San Francisco Bay).[citation needed]
The bay also continues to serve as a major seaport. The Port of Oakland is one of the largest cargo ports in the United States, while the Port of Richmond and the Port of San Francisco provide smaller services.[citation needed]
An additional crossing south of the Bay Bridge has long been proposed.
Recreation
San Francisco Bay is popular for sailors (boats, as well as windsurfing and kitesurfing), due to consistent strong westerly/northwesterly thermally-generated winds – Beaufort force 6 (15–25 knots; 17–29 mph; 8–13 m/s) is common on summer afternoons – and protection from large open ocean swells. Yachting and yacht racing are popular pastimes and the San Francisco Bay Area is home to many of the world's top sailors. A shoreline bicycle and pedestrian trail known as the San Francisco Bay Trail encircles the edge of the bay. The San Francisco Bay Area Water Trail, a growing network of launching and landing sites around the bay for non-motorized small boat users (such as kayakers) is being developed. Parks and protected areas around the bay include Eden Landing Ecological Reserve, Hayward Regional Shoreline, Don Edwards San Francisco Bay National Wildlife Refuge, Hayward Shoreline Interpretive Center, Crown Memorial State Beach, Eastshore State Park, Point Isabel Regional Shoreline, Brooks Island Regional Preserve, and César Chávez Park.
The California Office of Environmental Health Hazard Assessment (OEHHA) has developed a safe eating advisory for fish caught in the San Francisco Bay based on levels of mercury or PCBs found in local species.
The San Francisco Bay Area Water Trail is a planned system of designated trailheads designed to improve non-motorized small boat access to the bay. The California Coastal Conservancy approved funding in March 2011 to begin implementation of the water trail.
Gallery
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See also
- Golden Gate
- Golden Gate Bridge
- Hydrography of the San Francisco Bay Area
- Islands of San Francisco Bay
- J.C. Barthel, who prepared "plans for the docks and other water-front improvements in the San Francisco Bay district"
- McLaughlin Eastshore State Park
- Mount Diablo
- Mount Tamalpais State Park
- Napa Sonoma Marsh
- Point Pinole Regional Shoreline, Richmond
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- William Keener; Marc A. Webber; Tim M. Markowitz; Mark P. Cotter; Daniela Maldini; R. H. Defran; Megan Rice; Amanda J. Debich; Aimée R. Lang; Dennis L. Kelly; Alex G. Kesaris; Maddalena Bearzi; Kayla Causey; David Anderson; Laurie Shuster; David W. Weller (2023). "Northern Range Expansion of California Coastal Bottlenose Dolphins (Tursiops truncatus)". Aquatic Mammals. 49 (1): 29–43. doi:10.1578/AM.49.1.2023.29. S2CID 255918023.
- California State Water Resources Control Board (March 24, 2024). 2024 California Integrated Report: Surface Water Quality Assessments to Comply with Clean Water Act Sections 303(d) and 305(b). Sacramento, California. Retrieved August 15, 2024.
- Conaway, CH; Black, FJ; Grieb, TM; Roy, S; Flegal, AR (2008). "Mercury in the San Francisco Estuary". Reviews of Environmental Contamination and Toxicology. Vol. 194. pp. 29–54. doi:10.1007/978-0-387-74816-0_2. ISBN 978-0-387-74815-3. PMID 18069645.
{{cite book}}
:|journal=
ignored (help) - Bailey, Eric (November 9, 2007). "Oil oozes in S.F. Bay after ship hits bridge". Los Angeles Times. Archived from the original on March 22, 2019.
- Cloern, James E.; Schraga, Tara S.; Nejad, Erica; Martin, Charles (2020). "Nutrient Status of San Francisco Bay and Its Management Implications". Estuaries and Coasts. 43 (6): 1299–1317. Bibcode:2020EstCo..43.1299C. doi:10.1007/s12237-020-00737-w.
- Liz Kreutz. "Harmful algae bloom spreading across San Francisco Bay, turning water brown". ABC7 News. Archived from the original on February 28, 2024. Retrieved February 28, 2024.
- "Corkscrew Slough". Geographic Names Information System. United States Geological Survey, United States Department of the Interior.
- Sutton, Rebecca; Chen, Da; Sun, Jennifer; Greig, Denise J.; Wu, Yan (2019). "Characterization of brominated, chlorinated, and phosphate flame retardants in San Francisco Bay, an urban estuary". Science of the Total Environment. 652: 212–223. Bibcode:2019ScTEn.652..212S. doi:10.1016/j.scitotenv.2018.10.096. PMID 30366322. Archived from the original on April 3, 2019. Retrieved March 16, 2019.
- SFEI (2013). 2013 Pulse of the Bay: Contaminants of Emerging Concern. Richmond, California: San Francisco Estuary Institute. p. 98.
- Miller, Ezra; Mendez, Miguel; Shimabuku, Ila; Buzby, Nina; Sutton, Rebecca (September 2020). Contaminants of Emerging Concern in San Francisco Bay: A Strategy for Future Investigations 2020 Update (PDF). Richmond, California: San Francisco Estuary Institute. Retrieved March 16, 2021.
- Barnard, P. L.; Hanes, D. M.; Rubin, D. M.; Kvitek, R. G. (July 18, 2006). "Giant Sand Waves at the Mouth of San Francisco Bay" (PDF). Eos. 87 (29): 285, 289. Bibcode:2006EOSTr..87..285B. doi:10.1029/2006EO290003. Archived (PDF) from the original on August 19, 2018. Retrieved January 2, 2017.
- Sandifur, Marilyn (September 18, 2009). "50 Feet Delivered!". Port of Oakland. Archived from the original on February 19, 2017. Retrieved January 3, 2017.
- United States. Army. Corps of Engineers. San Francisco District, Port of Oakland (1998). Oakland harbor navigation improvement (−50-foot) project: draft environmental impact statement/environmental impact report: executive summary. U.S. Army Corps of Engineers, San Francisco District.
- "USA: Port of Oakland Secures USD 18 Million in Federal Funding for Dredging Project". Dredging Today. June 1, 2011. Archived from the original on June 20, 2012. Retrieved March 22, 2012.
- "USA: Congresswoman Helps Oakland Port Reach Major Funding Milestone for Deepening Project". Dredging Today. March 21, 2012. Archived from the original on June 20, 2012. Retrieved March 22, 2012.
- Matthews, Mark (March 22, 2012). "Huge container ship cruises into Port of Oakland". ABC7. San Francisco: KGO-TV/DT. Archived from the original on February 3, 2014. Retrieved March 23, 2012.
- Admin, OEHHA (December 30, 2014). "San Francisco Bay". OEHHA. Archived from the original on June 14, 2018. Retrieved June 13, 2018.
Literature
- The Bay of San Francisco: The metropolis of the Pacific Coast and its suburban cities: A history. Volume I. Lewis Publishing Company, Chicago, Ill. Published 1892. Contains index to biographical sketches
- Volume II – Biographies
External links
- San Francisco Bay: Portrait of an Estuary, David Sanger and John Hart, University of California Press
- Barging In – A Short History of Liveaboards on the Bay Archived August 19, 2018, at the Wayback Machine
- The Islands of San Francisco Bay, James A. Martin | Michael T. Lee, Down Window Press
- Army Corps of Engineers Bay Model: Working scale model of the Bay
- SF Bay Kayak, Canoe, and Boat Launch Ramp guide. A collaboratively edited guide to the SF bay.
- BoatingSF.com: Photos of SF Bay and its boats, plus online cruising guide
- Save San Francisco Bay: Protect and Restore San Francisco Bay
- sfbaywildlife.info Guide to San Francisco Bay wildlife
- Early History of the California Coast, a National Park Service Discover Our Shared Heritage Travel Itinerary
- Cartography & History The representations of San Francisco Bay: a portable harbor in the fragile geography of the North Pacific
- San Francisco Estuary and Watershed Science: a peer-reviewed online science journal
San Francisco Bay is a large tidal estuary in the U S state of California and gives its name to the San Francisco Bay Area It is dominated by the cities of San Francisco San Jose and Oakland San Francisco BaySan Francisco BayCoordinates37 40 N 122 16 W 37 67 N 122 27 W 37 67 122 27TypeBayRiver sourcesSacramento River San Joaquin River Petaluma River Napa River Guadalupe RiverOcean sea sourcesPacific OceanBasin countriesUnited StatesMax length97 km 60 mi Max width19 km 12 mi Surface area400 1 600 sq mi 1 000 4 100 km2 Average depth12 15 ft 3 7 4 6 m Max depth372 ft 113 m SettlementsSan Francisco San Jose OaklandRamsar WetlandOfficial nameSan Francisco Bay Estuary SFBE DesignatedFebruary 2 2013Reference no 2097Aerial panorama of the northern Bay the Bay Bridge Golden Gate and Marin Headlands on a clear morning November 2014 photo by Doc Searls San Francisco Bay drains water from approximately 40 percent of California Water from the Sacramento and San Joaquin rivers and from the Sierra Nevada mountains flow into Suisun Bay which then travels through the Carquinez Strait to meet with the Napa River at the entrance to San Pablo Bay which connects at its south end to San Francisco Bay It then connects to the Pacific Ocean via the Golden Gate strait However this entire group of interconnected bays is often called the San Francisco Bay The bay was designated a Ramsar Wetland of International Importance on February 2 2013 and the Port of Oakland on the bay is one of the busiest cargo ports on the west coast SizeThe bay covers somewhere between 400 and 1 600 square miles 1 000 4 000 km2 depending on which sub bays such as San Pablo Bay estuaries wetlands and so on are included in the measurement The main part of the bay measures three to twelve miles 5 19 km wide east to west and somewhere between 48 miles 77 km 1 and 60 miles 97 km 2 north to south San Francisco Bay is the second largest estuary on the Pacific coast of the Americas following the Salish Sea in Washington State and British Columbia Canada The bay was navigable as far south as San Jose until the 1850s when hydraulic mining released massive amounts of sediment from the rivers that settled in those parts of the bay that had little or no current Later wetlands and inlets were deliberately filled in reducing the bay s size since the mid 19th century by as much as one third Recently large areas of wetlands have been restored further confusing the issue of the bay s size Despite its value as a waterway and harbor many thousands of acres of marshy wetlands at the edges of the bay were for many years considered wasted space As a result soil excavated for building projects or dredged from channels was often dumped onto the wetlands and other parts of the bay as landfill citation needed From the mid 19th century through the late 20th century more than a third of the original bay was filled and often built on The deep damp soil in these areas is subject to soil liquefaction during earthquakes and most of the major damage close to the bay in the Loma Prieta earthquake of 1989 occurred to structures on these areas citation needed The Marina District of San Francisco hard hit by the 1989 earthquake was built on fill that had been placed there for the Panama Pacific International Exposition although liquefaction did not occur on a large scale In the 1990s San Francisco International Airport proposed filling in hundreds more acres to extend its overcrowded international runways in exchange for purchasing other parts of the bay and converting them back to wetlands The idea was and remains controversial For further details see the Bay fill and depth profile section There are five large islands in San Francisco Bay Alameda the largest island was created when a shipping lane was cut to form the Port of Oakland in 1901 It is now a suburban community Angel Island was known as Ellis Island West because it served as the entry point for immigrants from East Asia It is now a state park accessible by ferry Mountainous Yerba Buena Island is pierced by a tunnel linking the east and west spans of the San Francisco Oakland Bay Bridge Attached to the north is the artificial and flat Treasure Island site of the 1939 Golden Gate International Exposition From the Second World War until the 1990s both islands served as military bases and are now being redeveloped Isolated in the center of the bay is Alcatraz the site of the famous federal penitentiary The federal prison on Alcatraz Island no longer functions but the complex is a popular tourist site Despite its name Mare Island in the northern part of the bay is a peninsula rather than an island Panorama of San Francisco Bay and the city skyline seen from Marin County in the Golden Gate National Recreation AreaGeologyPopulation density and low elevation coastal zones in San Francisco Bay 2010 The San Francisco Bay is especially vulnerable to sea level rise San Francisco Bay is thought to represent a down warping of the Earth s crust between the San Andreas Fault to the west and the Hayward Fault to the east though the precise nature of this remains under study About 560 000 years ago a tectonic shift caused the large inland Lake Corcoran to spill out the central valley and through the Carquinez Strait carving out sediment and forming canyons in what is now the northern part of the San Francisco Bay and Golden Gate strait San Francisco Bay has been filled and emptied of sea water many times during the Pleistocene in accordance with sea level changes caused by glacial advances and retreats During the Wisconsin Glaciation between 15 000 and about 10 000 years ago the basin which is now filled by the San Francisco Bay was a large river valley with small hills channeling the Sacramento River through the Golden Gate Strait into the ocean When the great ice sheets began to melt around 11 000 years ago the sea level started to rise rapidly by about 1 inch per year Melting glaciers in the Sierra Nevada washed huge amounts of sediment down the Sacramento and San Joaquin rivers which accumulated on the shores of the bay forming huge mudflats and marshes that supported local wildlife By 5000 BC the sea level rose 300 feet 90 m filling the valley with water from the Pacific The Farallon Islands are what used to be hills along the old coastline and Potato Patch Shoal is an area of sand dunes now covered by the ocean HistoryCanizares Map of San Francisco Bay The indigenous inhabitants of the San Francisco Bay are Ohlone The first European to see San Francisco Bay is likely N de Morena who was left at New Albion at Drakes Bay in Marin County California by Sir Francis Drake in 1579 and then walked to Mexico The first recorded European discovery of San Francisco Bay was on November 4 1769 when Spanish explorer Gaspar de Portola unable to find the Port of Monterey continued north close to what is now Pacifica and reached the summit of the 1 200 foot high 370 m Sweeney Ridge now marked as the place where he first sighted San Francisco Bay Portola and his party did not realize what they had discovered thinking they had arrived at a large arm of what is now called Drakes Bay At the time Drakes Bay went by the name Bahia de San Francisco and thus both bodies of water became associated with the name Eventually the larger more important body of water fully appropriated the name San Francisco Bay citation needed The first European to enter the bay is believed to have been the Spanish explorer Juan de Ayala who passed through the Golden Gate on August 5 1775 in his ship the San Carlos and moored in a bay of Angel Island now known as Ayala Cove Ayala continued to explore the San Francisco Bay Area and the expedition s cartographer Jose de Canizares gathered the information necessary to produce the first map of the area A number of place names survive anglicized from that first map including Point Reyes Angel Island Farallon Islands and Alcatraz Island citation needed Alaskan Native sea otter hunters using Aleutian kayaks and working for the Russian American Company entered San Francisco Bay in 1807 and again over 1810 1811 Led by the Russian Timofei Nikitich Tarakanov these hunting raids probably wiped out sea otters in the bay Thousands of sea otter skins were taken to Sitka then Guangzhou Canton China where they commanded a high price The United States seized the region from Mexico during the Mexican American War 1846 1848 On February 2 1848 the Mexican province of Alta California was annexed to the United States with the signing of the Treaty of Guadalupe Hidalgo A year and a half later California requested to join the United States on December 3 1849 and was accepted as the 31st State of the Union on September 9 1850 citation needed San Francisco Bay Shoreline Tablet In 1921 a tablet was dedicated by a group of men in downtown San Francisco marking the site of the original shoreline The tablet reads This tablet marks the shore line of San Francisco Bay at the time of the discovery of gold in California January 24 1848 Map reproduced above delineates old shore line Placed by the Historic Landmarks committee Native Sons of the Golden West 1921 The bay became the center of American settlement and commerce in the Far West through most of the remainder of the 19th century During the California Gold Rush 1848 1855 San Francisco Bay suddenly became one of the world s great seaports dominating shipping in the American West until the last years of the 19th century The bay s regional importance increased further when the first transcontinental railroad was connected to its western terminus at Alameda on September 6 1869 The terminus was switched to the Oakland Long Wharf two months later on November 8 1869 The Dumbarton Rail Bridge In 1910 the Southern Pacific railroad company built the Dumbarton Rail Bridge the first bridge crossing San Francisco Bay The first automobile crossing was the Dumbarton Bridge completed in January 1927 More crossings were later constructed the Carquinez Bridge in May 1927 the San Francisco Oakland Bay Bridge in 1936 the Golden Gate Bridge in 1937 the Richmond San Rafael Bridge in 1956 and the San Mateo Hayward Bridge in 1967 Duck hunting on the Bay 1915Mallard II a clamshell dredge built in 1936 and used into the 21st century to dredge levees for Cargill s salt ponds in the bay During the 20th century the bay was subject to the 1940s Reber Plan which would have filled in parts of the bay in order to increase industrial activity along the waterfront In 1959 the United States Army Corps of Engineers released a report stating that if current infill trends continued the bay would be as big as a shipping channel by 2020 This news led to the creation of the Save the Bay movement in 1960 which mobilized to stop the infill of wetlands as well as the bay itself which had shrunk to two thirds of its size in the century before 1961 On September 17 1965 the California State Legislature enacted the McAteer Petris Act which created the San Francisco Bay Conservation and Development Commission Since then the Commission has strictly regulated bay fill Foster City Redwood Shores Paradise Cay and Emeryville s western expansion were among the last developments along the bay shoreline before McAteer Petris limited additional filling of the bay The San Francisco Bay continues to support some of the densest industrial production and urban settlement in the United States The San Francisco Bay Area is the American West s second largest urban area with approximately seven million residents EcologySan Francisco Bay c 1770 1820South Bay salt ponds and wildlife refuges aerial view from the southeast Despite its urban and industrial character San Francisco Bay and the Sacramento San Joaquin River Delta remain perhaps California s most important ecological habitats California s Dungeness crab California halibut and Pacific salmon fisheries rely on the bay as a nursery The few remaining salt marshes now represent most of California s remaining salt marsh supporting a number of endangered species and providing key ecosystem services such as filtering pollutants and sediments from the rivers San Francisco Bay is recognized for protection by the California Bays and Estuaries Policy with oversight provided by the San Francisco Estuary Partnership Most famously the bay is a key link in the Pacific Flyway Millions of waterfowl annually use the bay shallows as a refuge Two endangered species of birds are found here the California least tern and the Ridgway s Rail Exposed bay muds provide important feeding areas for shorebirds but underlying layers of bay mud pose geological hazards for structures near many parts of the bay perimeter San Francisco Bay provided the nation s first wildlife refuge Oakland s artificial Lake Merritt constructed in the 1860s and America s first urban National Wildlife Refuge the Don Edwards San Francisco Bay National Wildlife Refuge SFBNWR in 1972 The bay is also plagued by non native species citation needed Salt produced from San Francisco Bay is produced in salt evaporation ponds and is shipped throughout the Western United States to bakeries canneries fisheries cheese makers and other food industries and used to de ice winter highways clean kidney dialysis machines for animal nutrition and in many industries Many companies have produced salt in the bay with the Leslie Salt Company the largest private land owner in the Bay Area in the 1940s Low salinity salt ponds mirror the ecosystem of the bay with fish and fish eating birds in abundance Mid salinity ponds support dense populations of brine shrimp which provide a rich food source for millions of shorebirds Only salt tolerant micro algae survive in the high salinity ponds and impart a deep red color to these ponds from the pigment within the algae protoplasm The salt marsh harvest mouse is an endangered species endemic to the wetlands of the San Francisco Bay with a high salt tolerance It needs native pickleweed which is often displaced by invasive cordgrass for its habitat The seasonal range of water temperature in the bay is from January s 53 F 12 C to September s 60 F 16 C when measured at Fort Point which is near the southern end of the Golden Gate Bridge and at the entrance to San Francisco Bay For the first time in 65 years Pacific Harbor Porpoise Phocoena phocoena returned to the bay in 2009 Golden Gate Cetacean Research a non profit organization focused on research on cetaceans has developed a photo identification database enabling the scientists to identify specific porpoise individuals and is trying to ascertain whether a healthier bay has brought their return Pacific harbor porpoise range from Point Conception California to Alaska and across to the Kamchatka Peninsula and Japan Recent genetic studies show that there is a local stock from San Francisco to the Russian River and that eastern Pacific coastal populations rarely migrate far unlike western Atlantic Harbor porpoise The common bottlenose dolphin Tursiops truncatus has been extending its current range northwards from the Southern California Bight The first coastal bottlenose dolphin in the Bay Area in recent times was spotted in 1983 off the San Mateo County coast in 1983 In 2001 bottlenose dolphins were first spotted east of the Golden Gate Bridge and confirmed by photographic evidence in 2007 Zooarcheological remains of bottlenose dolphins indicated that bottlenose dolphins inhabited San Francisco Bay in prehistoric times until at least 700 years before present and dolphin skulls dredged from the bay suggest occasional visitors in historic times PollutionSan Francisco Bay faces many of the same water quality issues as other urban waterways in industrialized countries or downstream of intensive agriculture According to state water quality regulators San Francisco Bay waters do not meet water quality standards for the following pollutants DDT Mercury Selenium PCBs Polychlorinated biphenyls Dioxin compounds Furan Compounds Trash Diazinon Chlordane DieldrinMercury Industrial mining and other uses of mercury have resulted in a widespread distribution in the bay with uptake in the bay s phytoplankton and contamination of its sportfish Oil spills In January 1971 two Standard Oil tankers collided in the bay creating an 800 000 U S gallon 3 000 000 liter oil spill disaster which spurred environmental protection of the bay In November 2007 a ship named COSCO Busan collided with the San Francisco Oakland Bay Bridge and spilled over 58 000 U S gallons 220 000 liters of bunker fuel creating the largest oil spill in the region since 1996 Nutrients The bay also has some of the highest levels of dissolved inorganic nitrogen known from any coastal water body mostly originating from treated wastewater from Publicly owned treatment works In other bays such nutrient levels would likely lead to eutrophication but historically the bay has had less harmful algal blooms than other water bodies with similar nutrient concentrations Potential explanations have included the presence of intensive top down control from grazing clams like Potamocorbula high sediment supply limiting light availability for the algae and intensive tidal mixing The occurrence of an unprecedented harmful algal bloom of Heterosigma akashiwo in 2022 resulting in mass fish deaths and anoxia suggests that the mechanisms of control on algal growth may be eroding PBDEs The bay was once considered a hotspot for polybrominated diphenyl ether PBDE flame retardants used to make upholstered furniture and infant care items less flammable PBDEs have been largely phased out and replaced with alternative phosphate flame retardants A 2019 San Francisco Estuary Institute SFEI study assayed a wide range of these newer flame retardant chemicals in Bay waters bivalve California mussels Mytilus californianus and harbor seals Phoca vitulina which haul out in Corkscrew Slough on Bair Island in San Mateo County with phosphate flame retardant contaminants such as tris 1 3 dichloro 2 propyl phosphate TDCPP and triphenyl phosphate TPhP found at levels comparable to thresholds for aquatic toxicity Emerging contaminants Thousands of man made chemicals are found in Bay water sediment and organisms For many of these there is little or no data on their impacts on the environment or human health and they are not regulated by state or federal law These are often referred to as contaminants of emerging concern The San Francisco Estuary Institute has studied these chemicals in the Bay since 2001 Scientists have identified the following most likely to have a negative impact on Bay wildlife PFOS fipronil nonylphenols nonylphenol ethoxylatesCity skyline through the fog from the Golden Gate National Recreation AreaBay fill and depth profileSan Francisco Bay and the Golden Gate Bridge looking southeast towards the City and East Bay Alcatraz is the small islet in the upper middle left San Francisco Bay s profile changed dramatically in the late 19th century and again with the initiation of dredging by the US Army Corps of Engineers in the 20th century Before about 1860 most bay shores with the exception of rocky shores such as those in Carquinez Strait along Marin shoreline Point Richmond Golden Gate area contained extensive wetlands that graded nearly invisibly from freshwater wetlands to salt marsh and then tidal mudflat A deep channel ran through the center of the bay following the ancient drowned river valley citation needed In the 1860s and continuing into the early 20th century miners dumped staggering quantities of mud and gravel from hydraulic mining operations into the upper Sacramento and San Joaquin Rivers GK Gilbert s estimates of debris total more than eight times the amount of rock and dirt moved during construction of the Panama Canal This material flowed down the rivers progressively eroding into finer and finer sediment until it reached the bay system Here some of it settled eventually filling in Suisun Bay San Pablo Bay and San Francisco Bay in decreasing order of severity citation needed By the end of the 19th century these slickens had filled in much of the shallow bay flats raising the entire bay profile New marshes were created in some areas citation needed Cargo ships in San Francisco Bay in 2012 In the decades surrounding 1900 at the behest of local political officials and following Congressional orders the U S Army Corps began dredging the Sacramento and San Joaquin Rivers and the deep channels of San Francisco Bay This work has continued without interruption ever since Some of the dredge spoils were initially dumped in the bay shallows including helping to create Treasure Island on the former shoals to the north of Yerba Buena Island and used to raise islands in the Sacramento San Joaquin Delta The net effect of dredging has been to maintain a narrow deep channel deeper perhaps than the original bay channel through a much shallower bay At the same time most of the marsh areas have been filled or blocked off from the bay by dikes Large ships transiting the bay must follow deep underwater channels that are maintained by frequent dredging as the average depth of the bay is only as deep as a swimming pool approximately 12 to 15 ft 4 5 m Between Hayward and San Mateo to San Jose it is 12 to 36 in 30 90 cm The deepest part of the bay is under and out of the Golden Gate Bridge at 372 ft 113 m In the late 1990s a 12 year harbor deepening project for the Port of Oakland began it was largely completed by September 2009 Previously the bay waters and harbor facilities only allowed for ships with a draft of 46 ft 14 m but dredging activities undertaken by the United States Army Corps of Engineers in partnership with the Port of Oakland succeeded in providing access for vessels with a 50 foot 15 m draft Four dredging companies were employed in the US 432 million project with 244 million paid for with federal funds and 188 million supplied by the Port of Oakland Some six million cubic yards 160 million cubic feet 4 6 million cubic meters of mud from the dredging was deposited at the western edge of Middle Harbor Shoreline Park to become a 188 acre 0 294 sq mi 0 76 km2 shallow water wetlands habitat for marine and shore life Further dredging followed in 2011 to maintain the navigation channel This dredging enabled the arrival of the largest container ship ever to enter the San Francisco Bay the MSC Fabiola Bay pilots trained for the visit on a simulator at the California Maritime Academy for over a year The ship arrived drawing less than its full draft of 50 feet 10 inches 15 5 m because it held only three quarters of a load after its stop in Long Beach Transportation1 Richmond San Rafael Bridge2 Golden Gate Bridge3 San Francisco Oakland Bay Bridge4 San Mateo Hayward Bridge5 Dumbarton Bridge6 Carquinez Bridge7 Benicia Martinez Bridge8 Antioch Bridge San Francisco Bay was traversed by watercraft before the arrival of Europeans Indigenous peoples used canoes to fish and clam along the shoreline Sailing ships enabled transportation between the bay and other parts of the world and served as ferries and freighters within the bay and between the bay and inland ports such as Sacramento and Stockton These were gradually replaced by steam powered vessels starting in the late 19th century Several shipyards were established around the bay augmented during wartime e g the Kaiser Shipyards Richmond Shipyards near Richmond in 1940 for World War II for construction of mass produced assembly line Liberty and Victory cargo ships citation needed San Francisco Bay is spanned by nine bridges eight of which carry cars citation needed The Richmond San Rafael Bridge on Interstate 580 I 580 connects Marin and Contra Costa counties The Golden Gate Bridge on U S Route 101 State Route 1 US 101 SR 1 was the largest single span suspension bridge ever built at the time of its 1937 construction It spans the Golden Gate the strait between San Francisco and Marin County and is the only bridge in the area not owned by the State of California The San Francisco Oakland Bay Bridge on I 80 connects Alameda and San Francisco counties The San Mateo Hayward Bridge on SR 92 connects Alameda and San Mateo counties The Dumbarton Bridge on SR 84 connects Alameda and San Mateo counties The Carquinez Bridge including the Alfred Zampa Memorial Bridge on I 80 connects Contra Costa and Solano counties The Benicia Bridge on I 680 also connects Contra Costa and Solano counties The Antioch Bridge on SR 160 connects Contra Costa and Sacramento counties The Dumbarton Rail Bridge is an abandoned bridge that used to carry rail traffic The Transbay Tube an underwater rail tunnel carries BART services between Oakland and San Francisco citation needed Prior to the bridges and later the Transbay Tube transbay transportation was dominated by fleets of ferryboats operated by the Southern Pacific Railroad and the Key System transit company However in recent decades ferries have returned primarily serving commuters from Marin County relieving the traffic bottleneck of the Golden Gate Bridge see Ferries of San Francisco Bay citation needed Port of Oakland California The bay also continues to serve as a major seaport The Port of Oakland is one of the largest cargo ports in the United States while the Port of Richmond and the Port of San Francisco provide smaller services citation needed An additional crossing south of the Bay Bridge has long been proposed RecreationSan Francisco Bay is popular for sailors boats as well as windsurfing and kitesurfing due to consistent strong westerly northwesterly thermally generated winds Beaufort force 6 15 25 knots 17 29 mph 8 13 m s is common on summer afternoons and protection from large open ocean swells Yachting and yacht racing are popular pastimes and the San Francisco Bay Area is home to many of the world s top sailors A shoreline bicycle and pedestrian trail known as the San Francisco Bay Trail encircles the edge of the bay The San Francisco Bay Area Water Trail a growing network of launching and landing sites around the bay for non motorized small boat users such as kayakers is being developed Parks and protected areas around the bay include Eden Landing Ecological Reserve Hayward Regional Shoreline Don Edwards San Francisco Bay National Wildlife Refuge Hayward Shoreline Interpretive Center Crown Memorial State Beach Eastshore State Park Point Isabel Regional Shoreline Brooks Island Regional Preserve and Cesar Chavez Park The California Office of Environmental Health Hazard Assessment OEHHA has developed a safe eating advisory for fish caught in the San Francisco Bay based on levels of mercury or PCBs found in local species The San Francisco Bay Area Water Trail is a planned system of designated trailheads designed to improve non motorized small boat access to the bay The California Coastal Conservancy approved funding in March 2011 to begin implementation of the water trail San Francisco Bay panorama with a view of sailboats kite boarders and the Crissy Field BeachGallerySan Francisco from Forbes Island Pier 39 San Francisco Bay painting by Albert Bierstadt 1871 73 The City of Berkeley the San Francisco Bay and Marin County in the background as seen from the Claremont Canyon reserve Mount Tamalpais view across San Pablo Bay at Point Pinole Regional Shoreline in Richmond Looking north into San Pablo Bay at the Richmond San Rafael Bridge 2010 Alcatraz at dawn on San Francisco Bay Aerial view of Golden Gate and the northern Bay looking east from the Pacific People also swim recreationally at Kellar Beach in Richmond s Miller Knox Regional Shoreline Oil Spill in the bay RMS Queen Mary 2 in San Francisco Bay Fort Baker on San Francisco Bay just east of the Golden Gate NASA satellite image showing water flow Salt ponds at the southern tip of the bay The bay seen in July 2010 Ships at anchor in the baySee alsoSan Francisco Bay Area portalGolden Gate Golden Gate Bridge Hydrography of the San Francisco Bay Area Islands of San Francisco Bay J C Barthel who prepared plans for the docks and other water front improvements in the San Francisco Bay district McLaughlin Eastshore State Park Mount Diablo Mount Tamalpais State Park Napa Sonoma Marsh Point Pinole Regional Shoreline RichmondReferences San Francisco Bay Geographic Names Information System United States Geological Survey United States Department of the Interior January 19 1981 Retrieved January 2 2017 Anatomy of the Bay 7 bites of San Francisco Bay history science and lore July 6 2016 Archived from the original on May 24 2023 Retrieved May 24 2023 San Francisco Bay Estuary SFBE Ramsar Sites Information Service Archived from the original on June 14 2018 Retrieved April 25 2018 Symphonies in Steel San Francisco Oakland Bay Bridge and the Golden Gate Archived from the original on May 4 2015 Retrieved April 13 2005 San Francisco Bay Watershed Database and Mapping Project Archived October 30 2004 at the Wayback Machine BCDC The San Francisco Bay Estuary bcdc ca gov Archived from the original on February 17 2022 Retrieved February 14 2022 Jeffrey Mount Wim Kimmerer December 18 2022 The Largest Estuary on the West Coast of North America California WaterBlog Retrieved August 17 2024 The Formation of San Francisco Bay PDF KQED education Archived PDF from the original on July 19 2014 Retrieved June 4 2018 Konigsmark Ted 1998 Fort Funston PDF Geologic Trips San Francisco and the Bay Area Gualala California GeoPress ISBN 0 9661316 4 9 Yabrove Daniel December 9 2013 How the Bay was Born Save The Bay Blog Save The Bay Archived from the original on June 20 2018 Retrieved June 4 2018 Olmsted Nancy J Water on the Land The Coast People FoundSF Archived from the original on December 4 2019 Retrieved June 4 2018 Aker Raymond 1970 REPORT OF FINDINGS RELATING TO THE IDENTIFICATION OF SIR FRANCIS DRAKE S ENCAMPMENT AT POINT REYES NATIONAL SEASHORE PDF pp 338 340 Archived PDF from the original on April 15 2016 Retrieved April 19 2016 Charles F Lumis ed 1900 Narrative of the Pilot Morera who passed through the North Sea to the South Sea through the Strait The Land of Sunshine the Magazine of California and the West No February pp 184 186 Archived from the original on May 11 2017 Retrieved April 19 2016 Albert Salvador Bernabeu Redondo Jose Maria Garcia 2011 The representations of San Francisco California a portable harbor in the fragile geography of the North Pacific Antiteses 4 8 461 492 doi 10 5433 1984 3356 2011v4n8p461 S2CID 128670900 Owens Kenneth N 2015 Empire Maker Aleksandr Baranov and Russian Colonial Expansion into Alaska and Northern California University of Washington Press pp 211 231 ISBN 978 0295805832 Retrieved September 1 2024 Owens Kenneth N September 2006 Frontiersman for the Tsar Timofei Tarakanov and the Expansion of Russian America Montana The Magazine of Western History 56 3 Montana Historical Society 3 21 93 94 ISSN 0026 9891 JSTOR 4520817 Retrieved November 11 2023 Group of men standing around original shoreline tablet delivery library ca gov San Francisco California 1921 Archived from the original on October 6 2021 Retrieved October 6 2021 Alta California September 7 1869 Cprr org Archived from the original on July 9 2011 Retrieved August 10 2007 Schneider E J January 1913 Construction Problems Dumbarton Bridge Central California Railway Proceedings of the American Society of Civil Engineers 39 1 117 128 Retrieved March 14 2016 Emory Jerry 1995 Dumbarton Bridge amp Piers to Moffett Field In Gustaitis Rasa ed San Francisco Bay Shoreline Guide Berkeley California University of California Press p 48 ISBN 0 520 08878 6 Retrieved March 15 2016 The old Dumbarton Bridge Did you see it fall into the bay January 17 2017 Archived from the original on July 9 2021 Retrieved July 9 2021 The Barrier Broken Vallejo Evening Chronicle May 21 1927 Two Bay Area Bridges U S Department of Transportation January 18 2005 Archived from the original on October 11 2009 Retrieved June 13 2008 Key Dates Moments amp Events Golden Gate www goldengate org Archived from the original on June 29 2021 Retrieved July 9 2021 Frisco Adds Another Bridge To Skyline Sarasota Herald Tribune August 16 1956 Archived from the original on July 9 2021 Retrieved March 1 2016 San Mateo Hayward Bridge Facts California Department of Transportation 1995 Archived from the original on February 2 2015 Retrieved January 14 2015 Sylvia McLaughlin Citizen Activist for the Environment Saving San Francisco Bay Promoting Shoreline Parks and Natural Values in Urban and Campus Planning Oral History Center Bancroft Library University of California 2009 Archived from the original on February 28 2023 Retrieved February 28 2023 History Save the Bay Archived from the original on July 15 2015 Retrieved July 14 2015 Bay Area Census www bayareacensus ca gov Archived from the original on January 2 2016 Retrieved October 31 2018 State Water 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a href wiki Template Cite book title Template Cite book cite book a journal ignored help Bailey Eric November 9 2007 Oil oozes in S F Bay after ship hits bridge Los Angeles Times Archived from the original on March 22 2019 Cloern James E Schraga Tara S Nejad Erica Martin Charles 2020 Nutrient Status of San Francisco Bay and Its Management Implications Estuaries and Coasts 43 6 1299 1317 Bibcode 2020EstCo 43 1299C doi 10 1007 s12237 020 00737 w Liz Kreutz Harmful algae bloom spreading across San Francisco Bay turning water brown ABC7 News Archived from the original on February 28 2024 Retrieved February 28 2024 Corkscrew Slough Geographic Names Information System United States Geological Survey United States Department of the Interior Sutton Rebecca Chen Da Sun Jennifer Greig Denise J Wu Yan 2019 Characterization of brominated chlorinated and phosphate flame retardants in San Francisco Bay an urban estuary Science of the Total Environment 652 212 223 Bibcode 2019ScTEn 652 212S doi 10 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improvement 50 foot project draft environmental impact statement environmental impact report executive summary U S Army Corps of Engineers San Francisco District USA Port of Oakland Secures USD 18 Million in Federal Funding for Dredging Project Dredging Today June 1 2011 Archived from the original on June 20 2012 Retrieved March 22 2012 USA Congresswoman Helps Oakland Port Reach Major Funding Milestone for Deepening Project Dredging Today March 21 2012 Archived from the original on June 20 2012 Retrieved March 22 2012 Matthews Mark March 22 2012 Huge container ship cruises into Port of Oakland ABC7 San Francisco KGO TV DT Archived from the original on February 3 2014 Retrieved March 23 2012 Admin OEHHA December 30 2014 San Francisco Bay OEHHA Archived from the original on June 14 2018 Retrieved June 13 2018 LiteratureThe Bay of San Francisco The metropolis of the Pacific Coast and its suburban cities A history Volume I Lewis Publishing Company Chicago Ill Published 1892 Contains index to biographical sketches Volume II BiographiesExternal linksWikimedia Commons has media related to San Francisco Bay Wikisource has the text of the 1879 American Cyclopaedia article San Francisco Bay San Francisco Bay Portrait of an Estuary David Sanger and John Hart University of California Press Barging In A Short History of Liveaboards on the Bay Archived August 19 2018 at the Wayback Machine The Islands of San Francisco Bay James A Martin Michael T Lee Down Window Press Army Corps of Engineers Bay Model Working scale model of the Bay SF Bay Kayak Canoe and Boat Launch Ramp guide A collaboratively edited guide to the SF bay BoatingSF com Photos of SF Bay and its boats plus online cruising guide Save San Francisco Bay Protect and Restore San Francisco Bay sfbaywildlife info Guide to San Francisco Bay wildlife Early History of the California Coast a National Park Service Discover Our Shared Heritage Travel Itinerary Cartography amp History The representations of San Francisco Bay a portable harbor in the fragile geography of the North Pacific San Francisco Estuary and Watershed Science a peer reviewed online science journal