Alameda County, California
Alameda County is a county in the state of California in the United States. As of the 2010 census, the population was 1,510,271, making it the 7th-most populous county in the state; the county seat is Oakland. Alameda County is included in the San Francisco Bay Area; the Spanish word alameda means either, "...a grove of poplars...or a tree lined street" a name used to describe the Arroyo de la Alameda. The willow and sycamore trees along the banks of the river reminded the early Spanish explorers of a road lined with trees. Although a strict translation to English might be "Poplar Grove Creek", the name of the principal stream that flows through the county is now "Alameda Creek." Alameda County is included in the San Francisco–Oakland–Hayward, CA Metropolitan Statistical Area, included in the San Jose-San Francisco-Oakland, CA Combined Statistical Area. The county was formed on March 25, 1853, from a large portion of Contra Costa County and a smaller portion of Santa Clara County; the county seat at the time of the county's formation was located at Alvarado, now part of Union City.
In 1856, it was moved to San Leandro, where the county courthouse was destroyed by the devastating 1868 quake on the Hayward Fault. The county seat was re-established in the town of Brooklyn from 1872-1875. Brooklyn is now part of Oakland, the county seat since 1873. Much of what is now considered an intensively urban region, with major cities, was developed as a trolley car suburb of San Francisco in the late 19th and early 20th centuries; the historical progression from Native American tribal lands to Spanish Mexican ranches to farms and orchards to multiple city centers and suburbs, is shared with the adjacent and associated Contra Costa County. The annual county fair is held at the Alameda County Fairgrounds in Pleasanton; the fair runs for three weekends from June to July. Attractions include horse racing, carnival rides, 4-H exhibits, live bands. According to the U. S. Census Bureau, the county has a total area of 821 square miles, of which 739 square miles is land and 82 square miles is water.
The San Francisco Bay borders the county on the west, the City and County of San Francisco, has a small land border with the city of Alameda due to land filling. The crest of the Berkeley Hills form part of the northeastern boundary and reach into the center of the county. A coastal plain several miles wide lines the bay. Livermore Valley lies in the eastern part of the county. Amador Valley continues west to the Pleasanton Ridge; the Hayward Fault, a major branch of the San Andreas Fault to the west, runs through the most populated parts of Alameda County, while the Calaveras Fault runs through the southeastern part of the county. Don Edwards San Francisco Bay National Wildlife Refuge A 2014 analysis by The Atlantic found Alameda County to be the fourth most racially diverse county in the United States—behind Aleutians West Census Area and Aleutians East Borough in Alaska, Queens County in New York—as well as the most diverse county in California; the 2010 United States Census reported that Alameda County had a population of 1,510,271.
The population density was 2,047.6 people per square mile. The racial makeup of Alameda County was 649,122 White, 190,451 African American, 9,799 Native American, 394,560 Asian, 12,802 Pacific Islander, 162,540 from other races, 90,997 from two or more races. Hispanic or Latino of any race were 339,889 persons: 16.4% Mexican, 0.8% Puerto Rican, 0.2% Cuban, 5.1% Other Hispanic. As of the census of 2000, there were 1,443,741 people, 523,366 households, out of which 32.6% had children under the age of 18 living within them, 47.0% married couples living together, 13.0% had a female householder with no husband present, 35.2% were non-families. 26.0% of all households were made up of individuals and 7.3% had someone living alone, 65 years of age or older. The average household size was 2.71 and the average family size was 3.31. In the county, the population was spread out with 24.6% under the age of 18, 9.6% from 18 to 24, 33.9% from 25 to 44, 21.7% from 45 to 64, 10.2% who were 65 years of age or older.
The median age was 34 years. For every 100 females there were 96.60 males. For every 100 females age 18 and over, there were 94.00 males. The median income for a household in the county was $55,946, the median income for a family was $65,857. Males had a median income of $47,425 versus $36,921 for females; the per capita income for the county was $26,680. About 7.7% of families and 11.0% of the population were below the poverty line, including 13.5% of those under age 18 and 8.1% of those age 65 or over. In 2000, the largest denominational group was the Catholics; the largest religious bodies were Judaism. The Government of Alameda County is defined and authorized under the California Constitution, California law, the Charter of the County of Alameda. Much of the Government of California is in practice the responsibility of county governments such as the Government of Alameda County, while municipalities such as the city of Oakland and the city of Berkeley provide additional non-essential services.
The County government provides countywide services such as elections and voter registration, law enforceme
The Diablo Range is a mountain range in the California Coast Ranges subdivision of the Pacific Coast Ranges. It is located in the eastern San Francisco Bay area south to the Salinas Valley area of northern California, the United States; the Diablo Range extends from the Carquinez Strait in the north to Orchard Peak in the south, near the point where State Route 46 crosses over the Coast Ranges at Cholame, as described by the USGS. It is bordered on the northeast by the San Joaquin River, on the southeast by the San Joaquin Valley, on the southwest by the Salinas River, on the northwest by the Santa Clara Valley; the USGS designation is somewhat ambiguous north of the Santa Clara Valley, but on their maps, the range is shown as the ridgeline which runs between its namesake Mount Diablo southeastward past Mount Hamilton. Geologically, the range corresponds to the California Coast Ranges east of the Calaveras Fault in this northern section. For much of the length of the Diablo Range, it is paralleled by other sections of the California Coast Ranges to the west, the Santa Cruz Mountains across the southern San Francisco Bay and Santa Clara Valley, the Santa Lucia Range across the Salinas Valley.
The range passes through Contra Costa, San Joaquin, Santa Clara, Merced, San Benito, Fresno and Kings Counties, ends in the northwesternmost extremity of Kern County. Though the average elevation is about 3,000 feet, a summit at over 2,300 feet is considered high because the range is rolling grasslands and plateaus, punctuated by sudden peaks; the plateaus are at about 2,000–3,000 feet. The hills rising out of valleys rise to about 1,000 feet at most, the hills rolling around inland plateaus go from 1,500–2,500 feet. Foothills, such as the which are found near the Santa Clara Valley, Livermore Valley and San Joaquin Valley, are lowest, from 400–1,000 feet. Canyons are 300–400 feet deep and valleys are deeper but gentler; the peaks have high topographic prominence because they are surrounded by hills, valleys, or lower plateaus. Streams draining the eastern slopes of the Diablo Range include Ingram Creek. Stream draining the western slopes include Coyote Creek; the Diablo Range's following peaks and ridges are between 2,517–5,241 feet and are distinct landmarks.
Mount Diablo, San Benito Mountain, Mount Hamilton Ridge, Mount Stakes. The Diablo Range is paralleled for much of its distance by U. S. Route 101 by I-5 to the east. Major routes of travel through the range include: North of the range BNSF Railway/Amtrak San Joaquin Willow Pass State Route 4 Antioch–SFO/Millbrae BART Altamont Pass Union Pacific Railroad/Altamont Corridor Express I-580 Sunol Valley State Route 84 I-680 Pacheco Pass State Route 152 Future California High-Speed Rail State Route 198 Cottonwood Pass Polonio Pass A sparsely used gravel road is the highest road in the range, with its highest point being on San Benito Mountain at over 5,000 feet; the Diablo Range is unpopulated outside of the San Francisco Bay Area. Major nearby communities include Antioch, Walnut Creek, San Ramon, Livermore, Milpitas, San Jose, Morgan Hill, Gilroy. and the Central Valley city of Tracy. South of Pacheco Pass, the only major nearby communities are Los Banos, Hollister; the small town of Coalinga may be notable for its location on State Route 198, one of the few routes through the mountains.
Most of the range consists of private ranchland. However, the range does contain several areas of parkland, including Mount Diablo State Park, Alum Rock Park, Grant Ranch Park, Henry W. Coe State Park, Laguna Mountain Recreation Area, the BLM's Clear Creek Management Area. In addition, some private land is held in conservation easements by the California Rangeland Trust. Since the range lies around 10 to 50 miles inland from the ocean, other coastal ranges like the Santa Lucia Range and the Santa Cruz Mountains block incoming moisture, the range gets little precipitation. In addition, the average elevation of 3,000 feet is not high enough to catch most of the incoming moisture at higher altitudes. Winters are mild with moderate rainfall, but summers are dry and hot. Areas above 2,500 feet get light to moderate snow in the winter at the highest point, the 5,241 ft San Benito Mountain in the remote southeastern section of the range. However, though sites at the lower end get annual snowfall, it is light and melts too fast to be noticed.
Once or twice a decade there is deep and long lasting snowfall. Mercury contamination near the southern end of the range is an ongoing problem, due to the New Idria quicksilver mines, which stopped production in the 1970s. Heavy mercury contamination has been documented in the San Carlos and Silver Creeks, which flow into Panoche Creek, thence into the San Joaquin River; this has resulted in mercury contamination all the way downstream to the San Francisco Bay. Silver and San Carlos creeks provide a wetland environment in an otherwise arid region and are important for the ecology of the region; as of 2011, New Idria has been scheduled for cleanup. The Diablo Range is part of the California interior chaparral and woodlands ecoregion, it is covered by chaparral and California oak woodland communities, with stands of closed-cone pine forests appearing above 4,000 feet. The native bunch grass savanna has be
Geographic coordinate system
A geographic coordinate system is a coordinate system that enables every location on Earth to be specified by a set of numbers, letters or symbols. The coordinates are chosen such that one of the numbers represents a vertical position and two or three of the numbers represent a horizontal position. A common choice of coordinates is latitude and elevation. To specify a location on a plane requires a map projection; the invention of a geographic coordinate system is credited to Eratosthenes of Cyrene, who composed his now-lost Geography at the Library of Alexandria in the 3rd century BC. A century Hipparchus of Nicaea improved on this system by determining latitude from stellar measurements rather than solar altitude and determining longitude by timings of lunar eclipses, rather than dead reckoning. In the 1st or 2nd century, Marinus of Tyre compiled an extensive gazetteer and mathematically-plotted world map using coordinates measured east from a prime meridian at the westernmost known land, designated the Fortunate Isles, off the coast of western Africa around the Canary or Cape Verde Islands, measured north or south of the island of Rhodes off Asia Minor.
Ptolemy credited him with the full adoption of longitude and latitude, rather than measuring latitude in terms of the length of the midsummer day. Ptolemy's 2nd-century Geography used the same prime meridian but measured latitude from the Equator instead. After their work was translated into Arabic in the 9th century, Al-Khwārizmī's Book of the Description of the Earth corrected Marinus' and Ptolemy's errors regarding the length of the Mediterranean Sea, causing medieval Arabic cartography to use a prime meridian around 10° east of Ptolemy's line. Mathematical cartography resumed in Europe following Maximus Planudes' recovery of Ptolemy's text a little before 1300. In 1884, the United States hosted the International Meridian Conference, attended by representatives from twenty-five nations. Twenty-two of them agreed to adopt the longitude of the Royal Observatory in Greenwich, England as the zero-reference line; the Dominican Republic voted against the motion, while Brazil abstained. France adopted Greenwich Mean Time in place of local determinations by the Paris Observatory in 1911.
In order to be unambiguous about the direction of "vertical" and the "horizontal" surface above which they are measuring, map-makers choose a reference ellipsoid with a given origin and orientation that best fits their need for the area they are mapping. They choose the most appropriate mapping of the spherical coordinate system onto that ellipsoid, called a terrestrial reference system or geodetic datum. Datums may be global, meaning that they represent the whole Earth, or they may be local, meaning that they represent an ellipsoid best-fit to only a portion of the Earth. Points on the Earth's surface move relative to each other due to continental plate motion and diurnal Earth tidal movement caused by the Moon and the Sun; this daily movement can be as much as a metre. Continental movement can be up to 10 m in a century. A weather system high-pressure area can cause a sinking of 5 mm. Scandinavia is rising by 1 cm a year as a result of the melting of the ice sheets of the last ice age, but neighbouring Scotland is rising by only 0.2 cm.
These changes are insignificant if a local datum is used, but are statistically significant if a global datum is used. Examples of global datums include World Geodetic System, the default datum used for the Global Positioning System, the International Terrestrial Reference Frame, used for estimating continental drift and crustal deformation; the distance to Earth's center can be used both for deep positions and for positions in space. Local datums chosen by a national cartographical organisation include the North American Datum, the European ED50, the British OSGB36. Given a location, the datum provides the latitude ϕ and longitude λ. In the United Kingdom there are three common latitude and height systems in use. WGS 84 differs at Greenwich from the one used on published maps OSGB36 by 112 m; the military system ED50, used by NATO, differs from about 120 m to 180 m. The latitude and longitude on a map made against a local datum may not be the same as one obtained from a GPS receiver. Coordinates from the mapping system can sometimes be changed into another datum using a simple translation.
For example, to convert from ETRF89 to the Irish Grid add 49 metres to the east, subtract 23.4 metres from the north. More one datum is changed into any other datum using a process called Helmert transformations; this involves converting the spherical coordinates into Cartesian coordinates and applying a seven parameter transformation, converting back. In popular GIS software, data projected in latitude/longitude is represented as a Geographic Coordinate System. For example, data in latitude/longitude if the datum is the North American Datum of 1983 is denoted by'GCS North American 1983'; the "latitude" of a point on Earth's surface is the angle between the equatorial plane and the straight line that passes through that point and through the center of the Earth. Lines joining points of the same latitude trace circles on the surface of Earth called parallels, as they are parallel to the Equator and to each other; the North Pole is 90° N. The 0° parallel of latitude is designated the Equator, the fun
Mother lode is a principal vein or zone of gold or silver ore. The term is used colloquially to refer to the real or imaginary origin of something valuable or in great abundance; the term came from a literal translation of the Spanish veta madre, a term common in old Mexican mining. Veta madre, for instance, is the name given to an 11-kilometre-long silver vein discovered in 1548 in Guanajuato, New Spain. In the United States, Mother Lode is most famously the name given to a long alignment of hard-rock gold deposits stretching northwest-southeast in the Sierra Nevada of California, it was discovered during the California gold rush. The California Mother Lode is a zone from 1.5 to 6 kilometres wide and 190 kilometres long, between Georgetown on the north and Mormon Bar on the south. The Mother Lode coincides with the suture line of the Smartville Block; the zone contains hundreds of mines and prospects, including some of the best-known historic mines of the gold-rush era. Individual gold deposits within the Mother Lode are gold-bearing quartz veins up to 15 metres thick and a few thousand feet long.
The California Mother Lode was one of the most productive gold-producing districts in the United States. Now it is known for its vineyards; the California gold rush, as with most gold rushes, started with the discovery of placer gold in sands and gravels of streambeds, where the gold had eroded from the hard-rock vein deposits. Placer miners followed the gold-bearing sands upstream to discover the source in the bedrock; this source was the "mother" of the gold in the river and so was dubbed the "mother lode". Motherlode is a popular cheat code in The Sims. A ski lift at Park City Mountain Resort bears the name “Motherlode”. "Mother Lode" is a legend in Megaman Legends saga, rumored to be a valuable treasure that could provide so much power that the world never need to fear of running out of energy and make the wearer rich. Thom Yorke's second solo album “Tomorrow's Modern Boxes” from 2014 contains a song called “The Mother Lode.” Alaska Gold Rush California Gold Rush Gold Country Placer mining
Arroyo Valle or Arroyo Del Valle is a 36.4-mile-long westward-flowing stream that begins in northeastern Santa Clara County and flows northwesterly into Alameda County where it is dammed to form Lake Del Valle. After that Arroyo Valle is tributary to Arroyo de la Laguna which in turn flows into Alameda Creek and thence to San Francisco Bay. In the past, the Arroyo Valle had a significant steelhead migration. Arroyo Valle was once known as Arroyo De Los Taunamines, for the Costanoan Taunamines people who lived there. In 1853 it was renamed Arroyo del Valle; the stream drains much of the southern portion of the city of Livermore, it flows through and drains a considerable fraction of the city of Pleasanton, both in the Livermore Valley. Water quality measurements in this stream indicate a pH level of 7.0, or neutral with respect to acidity. In the middle reaches of Arroyo Valle south of Livermore, there has been considerable historic grazing use. Depth to groundwater in this reach of the watershed ranges from 50 feet to 100 feet and flows to the west.
Subsequent to this reach, the Arroyo del Valle flows down the moderately sloping hills to enter gravel pits, where extraction has been conducted by Lone Star Industries. Del Valle Dam forms the reservoir Lake Del Valle in southeastern Alameda County; the upper reaches of Arroyo Valle stretch into northeastern Santa Clara County where the mainstem is formed by the confluence of San Antonio Creek and Arroyo Bayo. San Antonio Creek's origin is on the western slope of 3,804 feet Mount Stakes, west of the Santa Clara-Stanislaus County border, about 32 miles southeast of Livermore. San Antonio Creek traverses the San Antonio Valley. Arroyo Bayo has its origin on Mount Stakes southwestern slope and traverses Upper San Antonio Valley as it heads west to Arroyo Valle. List of watercourses in the San Francisco Bay Area Arroyo de la Laguna Alameda Creek Arroyo Valle northern watershed map at Oakland Museum of California Current conditions for Arroyo Valle at US Geological Survey.