San Francisco Bay

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San Francisco Bay, San Pablo Bay , and the Golden Gate (satellite photo)
The bridges in the San Francisco Bay Area

The San Francisco Bay ( English San Francisco Bay ) is a through the Golden Gate (Golden Gate) with the Pacific associated sea bay of the Pacific Ocean in the west of the State of California . It is about 70 kilometers long and up to 20 kilometers wide. At about the same level as the cities of San Pablo and San Rafael , it merges into the Bay of San Pablo . The Bay of San Francisco is the most important estuary on the west coast of the North American continent.

The area surrounding the bay is known as the San Francisco Bay Area ( Area 'area') and forms a metropolitan area around the largest cities ( San José , San Francisco and Oakland ) in this region.

In the bay are the former prison island of Alcatraz , the artificial island of Treasure Island and the coast guard base Coast Guard Island .

history

The first European to sail the bay through the Golden Gate was likely the Spanish explorer Juan de Ayala . He passed the Golden Gate on August 5th, 1775 with his ship San Carlos , and anchored in a bay on Angel Island .

The Bay of San Francisco was the focus of American settlement in the far west in the 19th century. From the 1820s onwards, American presidents and expansionists coveted the bay because it could be used as a huge natural Pacific harbor . After many unsuccessful attempts to buy the bay and to change adjoining areas, the US Navy and Army conquered the region in the Mexican-American War (1845–1848), which had been in Mexican hands until then. During the California Gold Rush (1848–1850), San Francisco Bay immediately rose to become one of the world's most important seaports and dominated shipping and traffic in the American West until the last years of the 19th century. The bay became of paramount importance when the terminus of the transcontinental railroad was settled in Oakland in 1869 .

San Francisco Bay continues to have the densest industrial production and urban development in the United States . With nearly eight million inhabitants, it is the second largest urban area in West America.

Despite its usefulness as a maritime shipping route and port, the many square kilometers of marshy wetland surrounding the bay have long been viewed as a waste of land. As a result, earth excavated for building projects and dredged from canals was often dumped onto the marshland and other parts of the bay as filling. From the middle of the 18th to the late 19th century, more than a third of the original bay was shoveled and partially built on. The deep, moist soil in these areas repeatedly causes soil liquefaction during earthquakes , and most of the major damage near the bay during the Loma Prieta earthquake of 1989 was on structures in these areas. In the 1990s, the San Francisco International Airport proposed filling in more square kilometers to expand the crowded runways and in return acquire other parts of the bay to convert them back into wetlands. The idea was and remains controversial.

Ecology, flora and fauna

Panoramic view of the bay

Animal and nature protection

Despite its urban and industrial character, San Francisco Bay remains perhaps California's premier biotope . California's edible crabs (a crab ), Pacific halibut and Pacific salmon fisheries rely on the bay as a nursery. The few remaining salt marshes currently represent most of California's remaining salt marsh area. They are home to a great diversity of species and play a key role in the ecosystem . This is how they filter pollutants and sediments from the rivers.

The bay also plays an important role in the Pacific migratory route . Millions of waterfowl use their mudflats as a refuge every year .

Shore in the south of San Francisco

In the Bay of San Francisco, the San Francisco Bay National Wildlife Refuge (SFBNWR) was the first nature reserve in the USA to be established in a metropolitan area (1972). It consists in large part of salt evaporation ponds acquired or leased by the Leslie Salt Company and its successor, the Cargill Corporation . These salt basins produce salt for a variety of industrial purposes, e.g. B. Chlorine bleaching and plastics processing. In 2003, California and Cargill made one of the largest private land acquisitions in American history. The state and federal governments paid US $ 200 million for approximately 65 square kilometers of salt basins in the south of the bay. SFBNWR and state biologists hope to restore some of the now-acquired basins as tidal wetlands.

View of part of the Bay Model; the
Bay Bridge on the left

Model of the bay for hydraulic engineering, visitor center

The US Army Corps of Engineers once built a hydraulic model of San Francisco Bay and used it to study the environmental impact of the Reber Plan to dam the Bay of San Francisco. The model was later used to e.g. B. to investigate the effects of landfills and wastewater discharges, taking into account the freshwater inflows and the salt water of the Pacific flowing in and out during the day. With an area of ​​over 4000 square meters, this three-dimensional hydraulic model is one of the largest models ever built in the world and is unique of its kind. It enables measurements of changes in water temperature and salinity as well as the movement of oil spills and discharged toxins, so it is used to assess and defend against dangers. The model is no longer in operation, but can be viewed at the Bay Model Visitor Center in Sausalito (Sausalito is the first place after crossing the Golden Gate Bridge in a north direction).

Display boards and an audio tour provide information about the sensitive ecosystem of San Francisco Bay .

See also

Web links

Commons : San Francisco Bay  - Collection of Images, Videos, and Audio Files

Footnotes

literature

Coordinates: 37 ° 51 ′  N , 122 ° 22 ′  W