102-547: Big Bear Lake is a reservoir in the western United States, located in the San Bernardino Mountains in San Bernardino County , California. It is a snow and rain-fed lake, having no other means of tributaries or mechanical replenishment. At a surface elevation of 6,743 ft (2,055 m) above sea level , it has an east–west length of approximately seven miles (11 km) and
204-417: A dam constructed across a valley and rely on the natural topography to provide most of the basin of the reservoir. These reservoirs can either be on-stream reservoirs , which are located on the original streambed of the downstream river and are filled by creeks , rivers or rainwater that runs off the surrounding forested catchments, or off-stream reservoirs , which receive diverted water from
306-474: A 20 year period in the areas surrounding present day Humboldt County . One prospector in Southern California, William F. Holcomb (nicknamed "Grizzly Bill" Holcomb), was particularly well known for hunting grizzly bears in what is now San Bernardino County . During September 1897, in the mountains between Inwood and Mt. Lassen, Shasta County , 21-year-old Elias Weigart and his dog encountered
408-474: A Local Historic Civil Engineering Landmark by the American Society of Civil Engineers in 1972. Reservoir A reservoir ( / ˈ r ɛ z ər v w ɑːr / ; from French réservoir [ʁezɛʁvwaʁ] ) is an enlarged lake behind a dam , usually built to store fresh water , often doubling for hydroelectric power generation . Reservoirs are created by controlling
510-537: A block for migrating fish, trapping them in one area, producing food and a habitat for various water-birds. They can also flood various ecosystems on land and may cause extinctions. Creating reservoirs can alter the natural biogeochemical cycle of mercury . After a reservoir's initial formation, there is a large increase in the production of toxic methylmercury (MeHg) via microbial methylation in flooded soils and peat. MeHg levels have also been found to increase in zooplankton and in fish. Dams can severely reduce
612-550: A collaborative effort was initiated by scientists affiliated with the Research Network, prominent leaders from California Tribes, and advocates associated with conservation nonprofits. This initiative resulted in the establishment of the California Grizzly Alliance. Despite these efforts, however, their reintroduction remains controversial. Arguments against grizzly bear reintroduction emphasize
714-658: A conventional oil-fired thermal generation plant. For instance, In 1990, the impoundment behind the Balbina Dam in Brazil (inaugurated in 1987) had over 20 times the impact on global warming than would generating the same power from fossil fuels, due to the large area flooded per unit of electricity generated. Another study published in the Global Biogeochemical Cycles also found that newly flooded reservoirs released more carbon dioxide and methane than
816-533: A drop of water seep into the ocean without benefiting mankind." He created the reservoir named Parakrama Samudra ("sea of King Parakrama"). Vast artificial reservoirs were also built by various ancient kingdoms in Bengal, Assam, and Cambodia. Many dammed river reservoirs and most bank-side reservoirs are used to provide the raw water feed to a water treatment plant which delivers drinking water through water mains. The reservoir does not merely hold water until it
918-533: A fight, and supposedly gave the modern stock market its " bear " and " bull " nicknames based on the fighting styles of the two animals: the bear swipes downward while the bull hooks upward. In truth, the phrase's origins predate Greeley's 1859 journey to California by at least 100 years, but the myth of the California connection persists. The Monterey County Herald noted on July 4, 1874: Last Monday, Captain A. Smith, who resides about ten miles from town, in
1020-455: A grizzly bear in California occurred in 1603 when a Spanish explorer near Monterey described how bears came down to feed on a whale carcass stranded on the beach. However, his reports were not widely circulated, so the existence of grizzlies in California was not well-known to Europeans until the eighteenth century. Western Europeans' first well-circulated encounters with California grizzly bears are found in diaries kept by several members of
1122-522: A grizzly bear one ridge north of Bear Valley. There he noticed a vein of quartz flecked with gold. When this discovery was revealed, the Southern California gold rush was on, and Holcomb Valley quickly became the largest populated area in San Bernardino County. In 1884 marshy, nearly flat Bear Valley was dammed with a single arch granite impoundment, which held back some 25,000 acre-feet (31,000 dam) of water for irrigation purposes in
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#17327732796451224-455: A high-level reservoir is filled with water using high-performance electric pumps at times when electricity demand is low, and then uses this stored water to generate electricity by releasing the stored water into a low-level reservoir when electricity demand is high. Such systems are called pump-storage schemes. Reservoirs can be used in a number of ways to control how water flows through downstream waterways: Reservoirs can be used to balance
1326-471: A huge California grizzly whose front track measured 11 inches and the rear, 19. The bear died after Weigart emptied his Winchester 38-55 into the beast at close range. In 1920, the Shuteye Peak area of Madera County was home to one of the last California grizzlies, nicknamed 'Two Toes,' who lost part of his front foot in a trap and evaded hunters for years. The last hunted California grizzly bear
1428-520: A hunting party where the men were split into 11 pairs, each pair bringing back a bear hide. Wilson dubbed the grassy expanse "Bear Valley" and one of the nearby shallow seasonal marshes "Big Bear Lake". This same ephemeral feature is today called Baldwin Lake after Elias J. "Lucky" Baldwin of Rancho Santa Anita , who bought the nearby Gold Mountain Mine that was renamed for him in 1876. On Wilson's return trip,
1530-570: A loss in both quantity and quality of water necessary for maintaining ecological balance and pose a risk of increasing severity and duration of droughts due to climate change. In summary, they consider it a misadaptation to climate change. Proponents of reservoirs or substitution reserves, on the other hand, see them as a solution for sustainable agriculture while waiting for a truly durable agricultural model. Without such reserves, they fear that unsustainable imported irrigation will be inevitable. They believe that these reservoirs should be accompanied by
1632-655: A mainstay on restaurant menus in the San Gabriel area; according to Mike Davis , “The paws from adult bears and the flesh from young cubs were deemed particular delicacies.” European settlers paid bounties on the bears who regularly preyed on livestock until the early 20th century. Absolom (Rocky) Beasley hunted grizzly bears throughout the Santa Lucia Mountains and claimed to have killed 139 bears in his lifetime. Noted California mountain man Seth Kinman claimed to have shot over 800 grizzly bears in
1734-419: A narrow valley or canyon may cover relatively little vegetation, while one situated on a plain may flood a great deal of vegetation. The site may be cleared of vegetation first or simply flooded. Tropical flooding can produce far more greenhouse gases than in temperate regions. The following table indicates reservoir emissions in milligrams per square meter per day for different bodies of water. Depending upon
1836-470: A nearby stream or aqueduct or pipeline water from other on-stream reservoirs. Dams are typically located at a narrow part of a downstream of a natural basin. The valley sides act as natural walls, with the dam located at the narrowest practical point to provide strength and the lowest cost of construction. In many reservoir construction projects, people have to be moved and re-housed, historical artifacts moved or rare environments relocated. Examples include
1938-407: A period of record dating only back to 1960, the highest temperature recorded was 94 °F (34 °C), last recorded on July 15, 1998, while lowest was −25 °F (−32 °C) on January 29, 1979. Due to the 6,790 to 7,200 ft (2,070 to 2,190 m) elevation of the weather station, precipitation is greater than in the lowlands of San Bernardino County, averaging 21.15 in (537 mm)
2040-413: A point called The Village, the road turns toward the lake and then curves eastward to Moonridge, the ski resorts at Snow Summit and Bear Mountain, and Stanfield Cutoff, a causeway located near the east end of the lake. Big Bear Boulevard then continues east into Big Bear City , which is an unincorporated community despite its name. Bear Creek and Siberia Creek flow into the lake and Bear Creek flows out of
2142-584: A portion of Rancho Jurupa ( Riverside ) from Juan Bandini . He became a local rancher statesman. Wilson had signed on as Justice of the Peace of the Inland Territory and was commissioned by the territorial authorities to locate and pursue Native Americans suspected of raiding ranches in nearby Riverside. This group, led by the fierce Chief Walkara , drove the herd into the Lucerne Valley on
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#17327732796452244-611: A reservoir is called the "conservation pool". In the United Kingdom, "top water level" describes the reservoir full state, while "fully drawn down" describes the minimum retained volume. There is a wide variety of software for modelling reservoirs, from the specialist Dam Safety Program Management Tools (DSPMT) to the relatively simple WAFLEX , to integrated models like the Water Evaluation And Planning system (WEAP) that place reservoir operations in
2346-450: A river of variable quality or size, bank-side reservoirs may be built to store the water. Such reservoirs are usually formed partly by excavation and partly by building a complete encircling bund or embankment , which may exceed 6 km (4 miles) in circumference. Both the floor of the reservoir and the bund must have an impermeable lining or core: initially these were often made of puddled clay , but this has generally been superseded by
2448-740: A river valley, with the potential to wash away towns and villages and cause considerable loss of life, such as the devastation following the failure of containment at Llyn Eigiau which killed 17 people. (see also List of dam failures ) A notable case of reservoirs being used as an instrument of war involved the British Royal Air Force Dambusters raid on Germany in World War II (codenamed " Operation Chastise " ), in which three German reservoir dams were selected to be breached in order to damage German infrastructure and manufacturing and power capabilities deriving from
2550-561: A symbol of the short-lived California Republic . A second version was adopted as the state flag by the state legislature in 1911. The bear symbol became a permanent part of the state seal in 1849. The California grizzly bear was designated the official state animal in 1953. The bear is celebrated in name and as mascot of the sports teams of the University of California, Berkeley (the California Golden Bears ), and of
2652-582: A territorial project that unites all water stakeholders with the goal of preserving and enhancing natural environments. Two main types of reservoirs can be distinguished based on their mode of supply. Circa 3000 BC, the craters of extinct volcanoes in Arabia were used as reservoirs by farmers for their irrigation water. Dry climate and water scarcity in India led to early development of stepwells and other water resource management techniques, including
2754-468: A watercourse that drains an existing body of water, interrupting a watercourse to form an embayment within it, excavating, or building any number of retaining walls or levees to enclose any area to store water. The term is also used technically to refer to certain forms of liquid storage, such the "coolant reservoir" that captures overflow of coolant in an automobile's cooling system. Dammed reservoirs are artificial lakes created and controlled by
2856-504: A year. The maximum 24-hour precipitation was 9.43 in (240 mm) on December 6, 1966. Measurable precipitation normally occurs 44.9 days a year. Mountain thunderstorms occasionally produce heavy rainfall, even in midsummer (when most southern California lowland locations are quite dry). Big Bear Lake's climate is Csb ( Warm-summer Mediterranean ) under the Köppen climate classification . In contrast to most of southern California,
2958-476: Is a natural lake whose level was raised by a low dam and into which the River Dee flows or discharges depending upon flow conditions, as part of the River Dee regulation system . This mode of operation is a form of hydraulic capacitance in the river system. Many reservoirs often allow some recreational uses, such as fishing and boating . Special rules may apply for the safety of the public and to protect
3060-484: Is a water reservoir for agricultural use. They are filled using pumped groundwater , pumped river water or water runoff and are typically used during the local dry season. This type of infrastructure has sparked an opposition movement in France, with numerous disputes and, for some projects, protests, especially in the former Poitou-Charentes region where violent demonstrations took place in 2022 and 2023. In Spain, there
3162-559: Is accessible via three scenic highways: Highway 330 from San Bernardino, Highway 38 from Redlands, and Highway 18 from Victorville to the west, San Bernardino to the east. Public transit to and from San Bernardino, and among the communities surrounding the lake are provided by Mountain Transit . Big Bear Lake provides an attractive setting for many outdoor activities, including fishing (trout, bluegill, crappie, catfish and largemouth bass), pleasure boating, and water skiing. Because of
Big Bear Lake - Misplaced Pages Continue
3264-448: Is approximately 2.5 miles (4.0 km) at its widest measurement, though the lake's width mostly averages a little more than 1 ⁄ 2 mi (0.8 km). These approximations are based on the lake having an optimum retainable water level. At dam's end, Big Bear measures its deepest water at 72 feet (22 m). The region has been the ancestral home of the indigenous Serrano people for approximately 2,500 years. They referred to
3366-520: Is available. The California Office of Environmental Health Hazard Assessment (OEHHA) has developed an advisory for Big Bear Lake because of mercury and PCBs found in fish caught here. The advisory provides safe eating advice for black bass species, common carp, crappie, and rainbow trout. North Shore (west to east) South Shore (west to east) California Historical Landmark at the Big Bear Dam reads: The Bear Valley Dams were also designated as
3468-679: Is fraught with substantial land submergence, coastal reservoirs are preferred economically and technically since they do not use scarce land area. Many coastal reservoirs were constructed in Asia and Europe. Saemanguem in South Korea, Marina Barrage in Singapore, Qingcaosha in China, and Plover Cove in Hong Kong are a few such coastal reservoirs. Where water is pumped or siphoned from
3570-501: Is greater acceptance because all beneficiary users are involved in the implementation of the system. The specific debate about substitution reservoirs is part of a broader discussion related to reservoirs used for agricultural irrigation, regardless of their type, and a certain model of intensive agriculture. Opponents view these reservoirs as a monopolization of resources benefiting only a few, representing an outdated model of productive agriculture. They argue that these reservoirs lead to
3672-440: Is known to be an issue in brown bears. Pending further taxonomic resolution, the subspecies is provisionally accepted as separate. The California grizzly was historically considered an enormous bear. Father Pedro Font , an early missionary, described the local grizzly bears, writing, "He was horrible, fierce, large, and fat." In the 1800s, multiple newspaper accounts mentioned bears weighing well over 1,000 pounds (450 kg);
3774-466: Is needed: it can also be the first part of the water treatment process. The time the water is held before it is released is known as the retention time . This is a design feature that allows particles and silts to settle out, as well as time for natural biological treatment using algae , bacteria and zooplankton that naturally live in the water. However natural limnological processes in temperate climate lakes produce temperature stratification in
3876-536: Is now used by the Aquarius Golf Club. Service reservoirs perform several functions, including ensuring sufficient head of water in the water distribution system and providing water capacity to even-out peak demand from consumers, enabling the treatment plant to run at optimum efficiency. Large service reservoirs can also be managed to reduce the cost of pumping by refilling the reservoir at times of day when energy costs are low. An irrigation reservoir
3978-462: Is one of the most complex problems of mammalian taxonomy. The difficulty stems directly from the work of Merriam (1918), who concluded that there are 86 forms of grizzlies (and brown bears) in North America." North American brown bears were taxonomically grouped as a species apart from other bear species, until DNA testing revealed that they should properly be grouped in the same species as
4080-531: Is poorly suited to forming a single large reservoir, a number of smaller reservoirs may be constructed in a chain, as in the River Taff valley where the Llwyn-on , Cantref and Beacons Reservoirs form a chain up the valley. Coastal reservoirs are fresh water storage reservoirs located on the sea coast near a river mouth to store the flood water of a river. As the land-based reservoir construction
4182-419: Is stored in the reservoir. Any excess water can be spilled via a specifically designed spillway. Stored water may be piped by gravity for use as drinking water , to generate hydro-electricity or to maintain river flows to support downstream uses. Occasionally reservoirs can be managed to retain water during high rainfall events to prevent or reduce downstream flooding. Some reservoirs support several uses, and
Big Bear Lake - Misplaced Pages Continue
4284-473: Is the portion of the reservoir that can be used for flood control, power production, navigation , and downstream releases. In addition, a reservoir's "flood control capacity" is the amount of water it can regulate during flooding. The "surcharge capacity" is the capacity of the reservoir above the spillway crest that cannot be regulated. In the United States, the water below the normal maximum level of
4386-495: The 15 mi (24 km) "Arctic Circle" for a total distance of 33 mi (53 km) . Big Bear Lake can also be accessed by Hwy 38 (referred to as 'The Backside') at the San Bernardino (10) Freeway near Redlands , and takes a 52 mi (84 km) mile route that passes through Big Bear City on the east. From north of Lucerne Valley , it can be accessed by Highway 18 over the pass into Baldwin Lake and through
4488-722: The Big Bear Solar Observatory , past the Big Bear Discovery Center , past the Serrano Campground (U.S.F.S), accessing the public boat launch, and Stanfield Cutoff. North Shore Drive continues east into Big Bear City and Baldwin Lake . The primary approach to Big Bear is via Highway 330 out of San Bernardino through Running Springs where it intersects Highway 18. Highway 18 proceeds past Arrowbear and Snow Valley, over 7,200 ft (2,190 m) Lake Vista Summit and across
4590-459: The Redlands area. Redlands citrus growers found that the 1884 dam produced insufficient water. The Bear Valley Mutual Water Company (successor to Bear Valley Irrigation Company) hired John S. Eastwood to design a new dam. In 1912 (112 years ago) ( 1912 ) a 72 ft (22 m) multiple arch dam was constructed about 300 ft (91 m) downstream of the old dam and increased
4692-452: The Ruhr and Eder rivers. The economic and social impact was derived from the enormous volumes of previously stored water that swept down the valleys, wreaking destruction. This raid later became the basis for several films. All reservoirs will have a monetary cost/benefit assessment made before construction to see if the project is worth proceeding with. However, such analysis can often omit
4794-514: The U.S. Fish and Wildlife Service received, and subsequently rejected, a petition to reintroduce grizzly bears to California. In 2015, the Center for Biological Diversity launched a petition aimed at the California state legislature to reintroduce the grizzly bear to the state. In anticipation of the 2024 centennial marking the final recorded sighting of a wild grizzly bear in California,
4896-461: The grizzly bear . "Grizzly" could have meant "grizzled" – that is, with golden and grey tips of the hair – or "fear-inspiring" (as a phonetic spelling of "grisly"). Nonetheless, after careful study, naturalist George Ord formally classified it in 1815 – not for its hair, but for its character – as Ursus horribilis ("terrifying bear"). Genetically, North American brown bears are closely related; in size and coloring,
4998-419: The ranchos of California provided an abundant food source for the bears, allowing the grizzly population to expand rapidly. However, the cattle population was greatly diminished following extreme drought and flooding in the 1860s and 1870s, leading to a reduction in the number of grizzlies. This coincided with an increased interest in bear hunting, both for sport and commercial purposes. Grizzly bear meat became
5100-505: The 1769 Portola expedition , the first European land exploration of what is now the state of California. Several place names that include the Spanish word for bear ( oso ) trace their origins back to that first overland expedition (e.g. Los Osos ). As the settled frontier of New Spain was extended northward, settlers began to populate California and establish large cattle herds as the main industry. The ranchers' livestock were easy prey for
5202-673: The 1800s, most of which are lined with brick. A good example is the Honor Oak Reservoir in London, constructed between 1901 and 1909. When it was completed it was said to be the largest brick built underground reservoir in the world and it is still one of the largest in Europe. This reservoir now forms part of the southern extension of the Thames Water Ring Main . The top of the reservoir has been grassed over and
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#17327732796455304-481: The Big Bear Lake region normally receives significant winter snow because of its high elevation. Snowfall, as measured at lake level, averages 72 in (180 cm) per season; upwards of 100 in (250 cm) can accumulate on the forested ridges bordering the lake, at elevation above 8,000 ft (2,400 m). In February 1990, 59.5 in (151 cm) of snow were recorded. The most snow in 24 hours
5406-424: The California grizzly bear has been described as golden brown, leading to the occasional name "California golden bear". The captive individual "Monarch" had a dark brown, almost black, pelt. The diet of the California grizzly bear was diverse, ranging from plant sources like grasses, seeds, berries, and acorns, to animal sources such as elk, deer, salmon , steelhead , and carrion. Isotopic study indicates that
5508-615: The California grizzly bear was much like the Kodiak bear of the southern coast of Alaska. The grizzly became a symbol of the Bear Flag Republic , a moniker that was attached to the short-lived attempt by a group of U.S. settlers to break away from Mexico in 1846. Later, this rebel flag became the basis for the state flag of California , and then California was known as the "Bear State". A 1953 researcher stated, "The specific status of North American brown bears (or grizzly bears)
5610-480: The Carmel Valley, succeeded in poisoning a large grizzly bear. Bruin had been annoying the neighborhood by destroying cattle, etc., for several years past, and all efforts to exterminate him seem futile. In some manner, however, he was induced partake of that "cold pizen" the captain had prepared for his special benefit. He is not likely to repeat his experiment. In the early to mid 19th century, livestock from
5712-731: The Meroitic town of Butana . The Hafirs catch the water during rainy seasons in order to ensure water is available for several months during dry seasons to supply drinking water, irrigate fields and water cattle. The Great Reservoir near the Lion Temple in Musawwarat es-Sufra is a notable hafir in Kush. In Sri Lanka , large reservoirs were created by ancient Sinhalese kings in order to store water for irrigation. The famous Sri Lankan king Parākramabāhu I of Sri Lanka said "Do not let
5814-488: The US. The capacity, volume, or storage of a reservoir is usually divided into distinguishable areas. Dead or inactive storage refers to water in a reservoir that cannot be drained by gravity through a dam's outlet works , spillway, or power plant intake and can only be pumped out. Dead storage allows sediments to settle, which improves water quality and also creates an area for fish during low levels. Active or live storage
5916-544: The amount of water reaching countries downstream of them, causing water stress between the countries, e.g. the Sudan and Egypt , which damages farming businesses in the downstream countries, and reduces drinking water. Ursus californicus The California grizzly bear ( Ursus arctos californicus ), also known as the California golden bear , is an extinct population of the brown bear , generally known (together with other North American brown bear populations) as
6018-563: The area feature place names reflecting the Big Bear region's rich Native history. These include Yucaipa , Cucamonga , and Muscupiabe. European explorers first saw the area when a Native American hunting party was formed by Benjamin Wilson . Wilson moved to California during the days of Mexican territorial Alta California . He married into the Spanish landholder family, the Yorbas, and bought
6120-535: The area flooded versus power produced, a reservoir built for hydro- electricity generation can either reduce or increase the net production of greenhouse gases when compared to other sources of power. A study for the National Institute for Research in the Amazon found that hydroelectric reservoirs release a large pulse of carbon dioxide from decay of trees left standing in the reservoirs, especially during
6222-428: The base of the dam or some distance away. In a flat river valley a reservoir needs to be deep enough to create a head of water at the turbines; and if there are periods of drought the reservoir needs to hold enough water to average out the river's flow throughout the year(s). Run-of-the-river hydro in a steep valley with constant flow needs no reservoir. Some reservoirs generating hydroelectricity use pumped recharge:
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#17327732796456324-675: The bear, but differ as to its exact size.) Her telling of that bear is part of the oral history of "Bear Valley", the original name for Valley Center. The bear was prominent in the Big Sur region of the central California coast. Frank Post , born in 1859 on the Soberanes Ranch in Big Sur, remembered when his family lived at Soberanes Creek, during the American Civil War – recalling the "Great Sur Bears". Inhabiting most of
6426-465: The build, often through a temporary tunnel or by-pass channel. In hilly regions, reservoirs are often constructed by enlarging existing lakes. Sometimes in such reservoirs, the new top water level exceeds the watershed height on one or more of the feeder streams such as at Llyn Clywedog in Mid Wales . In such cases additional side dams are required to contain the reservoir. Where the topography
6528-556: The building of a reservoir at Girnar in 3000 BC. Artificial lakes dating to the 5th century BC have been found in ancient Greece. The artificial Bhojsagar lake in present-day Madhya Pradesh state of India, constructed in the 11th century, covered 650 square kilometres (250 sq mi). The Kingdom of Kush invented the Hafir , a type of reservoir, during the Meroitic period . 800 ancient and modern hafirs have been registered in
6630-442: The context of system-wide demands and supplies. In many countries large reservoirs are closely regulated to try to prevent or minimize failures of containment. While much of the effort is directed at the dam and its associated structures as the weakest part of the overall structure, the aim of such controls is to prevent an uncontrolled release of water from the reservoir. Reservoir failures can generate huge increases in flow down
6732-606: The dam and other assets from the Mutual Water Company in 1977. The unregulated hunting of grizzly bear in the San Bernardinos took a heavy toll upon the once significant population, and by 1906 all the local Ursus californicus were killed off. Tourism began with the onset of the automobile and the eventual establishment of highways accessing the remote area. Hollywood soon discovered Big Bear, and several movies, particularly westerns, have been filmed in
6834-460: The developed world Naturally occurring lakes receive organic sediments which decay in an anaerobic environment releasing methane and carbon dioxide . The methane released is approximately 8 times more potent as a greenhouse gas than carbon dioxide. As a human-made reservoir fills, existing plants are submerged and during the years it takes for this matter to decay, will give off considerably more greenhouse gases than lakes do. A reservoir in
6936-507: The downstream river to maintain river quality, support fisheries, to maintain downstream industrial and recreational uses or for a range of other purposes. Such releases are known as compensation water . The units used for measuring reservoir areas and volumes vary from country to country. In most of the world, reservoir areas are expressed in square kilometers; in the United States, acres are commonly used. For volume, either cubic meters or cubic kilometers are widely used, with acre-feet used in
7038-440: The environmental impacts of dams and the reservoirs that they contain. Some impacts, such as the greenhouse gas production associated with concrete manufacture, are relatively easy to estimate. Other impacts on the natural environment and social and cultural effects can be more difficult to assess and to weigh in the balance but identification and quantification of these issues is now commonly required in major construction projects in
7140-499: The first decade after flooding. This elevates the global warming impact of the dams to levels much higher than would occur by generating the same power from fossil fuels . According to the World Commission on Dams report (Dams And Development), when the reservoir is relatively large and no prior clearing of forest in the flooded area was undertaken, greenhouse gas emissions from the reservoir could be higher than those of
7242-413: The flow in highly managed systems, taking in water during high flows and releasing it again during low flows. In order for this to work without pumping requires careful control of water levels using spillways . When a major storm approaches, the dam operators calculate the volume of water that the storm will add to the reservoir. If forecast storm water will overfill the reservoir, water is slowly let out of
7344-487: The hind foot of one particular adult male grizzly was measured at 12 inches (300 mm) long by 8 inches (200 mm) wide, and claws were often 2 inches (51 mm) wide by 3.5 inches (89 mm) long. Measurements of museum specimens, however, demonstrate that this bear was no larger than those present in the rest of North America, with average body size estimates ranging from 104 kilograms (229 lb) to 252 kilograms (556 lb) depending on methodology. The fur of
7446-580: The hydroelectric reservoirs there do emit greenhouse gases, it is on a much smaller scale than thermal power plants of similar capacity. Hydropower typically emits 35 to 70 times less greenhouse gases per TWh of electricity than thermal power plants. A decrease in air pollution occurs when a dam is used in place of thermal power generation, since electricity produced from hydroelectric generation does not give rise to any flue gas emissions from fossil fuel combustion (including sulfur dioxide , nitric oxide and carbon monoxide from coal ). Dams can produce
7548-495: The lake capacity to 73,000 acre-feet (90,000 dam). The original granite dam still remains, usually under about 20 feet of water. A highway bridge (SR 18) was built over the arches of the new dam in 1923. A new bypass bridge was built next to the old bridge in 2009, and the old bridge on top of the new dam was removed. Elevation at the surface is 6,750 ft (2,060 m), but this level fluctuates according to annual snowmelt and runoff. Big Bear Municipal Water District acquired
7650-532: The lake, traveling about 9 miles (14 km) southwest to the Santa Ana River . North Shore ( Highway 38 ) begins at the Dam Junction of Highway 18. It travels east past the historic location of Gray's Landing, a famous 1920s fishing camp. It turns north around Grout Bay and travels through the small unincorporated town of Fawnskin . The road meanders across North Shore through Forestry lands, past
7752-432: The landscape is relatively flat. Other service reservoirs can be storage pools, water tanks or sometimes entirely underground cisterns , especially in more hilly or mountainous country. Modern reserviors will often use geomembrane liners on their base to limit seepage and/or as floating covers to limit evaporation, particularly in arid climates. In the United Kingdom, Thames Water has many underground reservoirs built in
7854-465: The largely herbivorous-omnivorous grizzly bears found across the state. In turn, grizzly populations increased around human settlements. By eating their livelihood, and scaring them, the grizzlies became enemies of the rancheros . Vaqueros hunted the grizzlies, often roping and capturing them alive to be pitted against other animals in public battles ( bloodsports ). In 1866, a grizzly bear described as weighing as much as 2,200 pounds (1,000 kg)
7956-501: The majority of the diet consisted of plant matter, as with other grizzly bear populations. Anecdotal reports from Spanish explorers reported California grizzly bears scavenging on beached whale carcasses. After the introduction of European livestock, California grizzly bears increasingly incorporated cattle into their diets. California grizzly bears were primarily solitary, except for mothers with cubs, but foraging groups of up to 40 have been reported. Prior to Spanish settlement in
8058-470: The modern use of rolled clay. The water stored in such reservoirs may stay there for several months, during which time normal biological processes may substantially reduce many contaminants and reduce turbidity . The use of bank-side reservoirs also allows water abstraction to be stopped for some time, for instance when the river is unacceptably polluted or when flow conditions are very low due to drought . The London water supply system exhibits one example of
8160-523: The north side of the San Bernardinos. In 1845, Wilson gathered a posse of 44 men, 22 of whom he sent through the Cajon Pass while he engineered a pincer movement with the other 22 men into the headwaters of the Santa Ana River , effectively cutting the Utes off at the other end of Lucerne. On the trip Wilson came upon a broad watershed teeming with wildlife, particularly bear. His posse immediately became
8262-592: The north side, into Big Bear City. According to the National Weather Service, the warmest month at Big Bear is July, with a daily average temperature of 64.7 °F (18.2 °C). The coolest month is January, with a daily average temperature of 34.1 °F (1.2 °C). There are an average of 1.7 days each year with highs of 90 °F (32 °C) or higher. Freezing temperatures have occurred in every month and occur on an average of 186 days each year, on average from September 24 to June 4. With
8364-415: The operating rules may be complex. Most modern reservoirs have a specially designed draw-off tower that can discharge water from the reservoir at different levels, both to access water as the water level falls, and to allow water of a specific quality to be discharged into the downstream river as "compensation water": the operators of many upland or in-river reservoirs have obligations to release water into
8466-474: The other brown bears. Grizzlies living in California had been classified by Merriam into many subspecies. A recent study based on mitochondrial DNA suggests that the only genetically anomalous grouping of grizzly bears is the ABC Islands bear , implying that previous grizzly bear subspecies designations are unwarranted. However, a formal taxonomic synonymy was not performed, and mitochondrial introgression
8568-551: The party took 11 more bear pelts. In 1859, the valley became a venue for gold prospectors. William F. Holcomb , a prospector from Indiana, moved to Los Angeles from the Northern California mines where he heard about the prospecting at Big Bear. He moved to Starvation Flats , where he had little luck the first winter. Because of his marksmanship, he was hired by several of the other miners to hunt bear for meat. With his Indian companion, Holcomb tracked, shot and wounded
8670-430: The potential for rare but significant harm, such as attacks causing injuries or fatalities. Those who deem any harm, especially loss of human life, as morally unacceptable view the reintroduction in California as an intolerable threat, regardless of individual risk. The California grizzly bear is one of the state's most visible and enduring symbols, adorning both the state flag and seal. The Bear Flag first flew in 1846 as
8772-481: The pre-flooded landscape, noting that forest lands, wetlands, and preexisting water features all released differing amounts of carbon dioxide and methane both pre- and post-flooding. The Tucuruí Dam in Brazil (completed in 1984) had only 0.4 times the impact on global warming than would generating the same power from fossil fuels. A two-year study of carbon dioxide and methane releases in Canada concluded that while
8874-437: The quality of the water and the ecology of the surrounding area. Many reservoirs now support and encourage less formal and less structured recreation such as natural history , bird watching , landscape painting , walking and hiking , and often provide information boards and interpretation material to encourage responsible use. Water falling as rain upstream of the reservoir, together with any groundwater emerging as springs,
8976-594: The region. Big Bear Lake is geophysically defined by its North and South Shore. Big Bear Boulevard follows the South Shore and leads into the Big Bear Valley as a continuation of Highway 18 (the so-called Rim of the World Highway, which approaches from the west). Big Bear Boulevard winds east through Papoose Bay, Boulder Bay and Metcalf Bay, then leads directly east to the city of Big Bear Lake. At
9078-638: The reservoir prior to, and during, the storm. If done with sufficient lead time, the major storm will not fill the reservoir and areas downstream will not experience damaging flows. Accurate weather forecasts are essential so that dam operators can correctly plan drawdowns prior to a high rainfall event. Dam operators blamed a faulty weather forecast on the 2010–2011 Queensland floods . Examples of highly managed reservoirs are Burrendong Dam in Australia and Bala Lake ( Llyn Tegid ) in North Wales . Bala Lake
9180-523: The second half of the 1700s , it is estimated that 10,000 grizzly bears inhabited what is modern-day California. It is thought that the bears lived across almost the entirety of the state, save its most southeastern and northeastern corners. Probably the southernmost records for this subspecies are from the Sierra de Juárez , during the 18th century. The bear was most abundant in chaparral, oak woodland, and hardwood forests. The first documented sighting of
9282-407: The state is growing. Despite having one of the largest American black bear populations in the nation, California still has habitat that can sustain about 500 grizzlies; it is thought that the presence of an additional large mammal could curb overpopulation of the smaller black bear, which often is involved in human-bear conflicts, as it enters human settlements in pursuit of food and trash. In 2014,
9384-591: The state, both inland and coastally, it is likely the California grizzly's southernmost range in the state overlapped with that of the now-extinct Mexican grizzly bear , as well. In the late 1700s, Spanish ranchers placed a poisoned "bait ball" made of suet or swine entrails filled with a lethal dose of strychnine which they hung from the branches of a tree within reach of the bear but out of reach of dogs and children. Mexican settlers captured bears for bear and bull fights and they also sold their skins for 6 to 10 pesos to trading ships. Bear Trap Canyon near Bixby Creek
9486-587: The temples of Abu Simbel (which were moved before the construction of the Aswan Dam to create Lake Nasser from the Nile in Egypt ), the relocation of the village of Capel Celyn during the construction of Llyn Celyn , and the relocation of Borgo San Pietro of Petrella Salto during the construction of Lake Salto . Construction of a dammed reservoir will usually require the river to be diverted during part of
9588-405: The territory as "Yuhaviat" which translates into "Pine Place". They inhabited small villages of 10 to 30 round buildings located along fresh water sources and subsisted on berries, nuts, tubers, acorns, and plentiful game harvested along the lush valley. The Serrano looked at the native grizzly bears as ancestors and did not eat the meat or wear the fur of these massive animals. Several communities in
9690-499: The use of bank-side storage: here water is taken from the River Thames and River Lee into several large Thames-side reservoirs, such as Queen Mary Reservoir that can be seen along the approach to London Heathrow Airport . Service reservoirs store fully treated potable water close to the point of distribution. Many service reservoirs are constructed as water towers , often as elevated structures on concrete pillars where
9792-625: The very cold water and the presence of underwater obstacles near the shorelines, swimming is discouraged. The lake is patrolled by the BBMWD Lake Patrol. Many lakeside residents have private docks, and visiting boaters obtain mooring in several of the marinas found on both shores. Big Bear Municipal Water District (a special district of the State of California) provides public launches on the east end and west end of North Shore. Local marinas rent various sport and pleasure boats, and parasailing
9894-412: The water, which tends to partition some elements such as manganese and phosphorus into deep, cold anoxic water during the summer months. In the autumn and winter the lake becomes fully mixed again. During drought conditions, it is sometimes necessary to draw down the cold bottom water, and the elevated levels of manganese in particular can cause problems in water treatment plants. In 2005, about 25% of
9996-476: The world's 33,105 large dams (over 15 metres in height) were used for hydroelectricity. The U.S. produces 3% of its electricity from 80,000 dams of all sizes. An initiative is underway to retrofit more dams as a good use of existing infrastructure to provide many smaller communities with a reliable source of energy. A reservoir generating hydroelectricity includes turbines connected to the retained water body by large-diameter pipes. These generating sets may be at
10098-484: Was 27.0 in (69 cm) on March 27, 1991. The greatest snow depth was 58 in (150 cm) on February 3, 1979. Snow has fallen in every month except July and August. There are normally 18 days each year with measurable snow of .1 in (0.25 cm) or more. Located 100 miles (160 km) east of Los Angeles and surrounded by the San Bernardino National Forest , Big Bear Lake
10200-481: Was killed in what is present-day Valley Center, California , in the north-central area of San Diego County . The incident was recalled in 1932 by Catherine E. Lovett Smith, who witnessed the bear's killing on her family's ranch when she was just six years old. If its measurements are accurate, this particular bear was the biggest bear ever found in California and one of the largest specimens of any bear species ever recorded. (Other sources confirm Lovett Smith's account of
10302-614: Was one of their favorite sites for trapping grizzly bears along the central California coast. These bears were even turned into furniture, such as a chair gifted to President Andrew Johnson in 1865. Bear-baiting events flourished as popular spectacles in 19th century California. Bloody fights that pitted bears against bulls often inspired betting as to whether the bear or the bull would win. One persistently popular, but false phrase origin story related to these fights stems from famous 19th-century newspaperman Horace Greeley . While visiting California, Greeley allegedly witnessed such
10404-631: Was shot in Tulare County, California , in August 1922, although no body, skeleton or pelt was ever produced. Less than 75 years after the discovery of gold in 1848, almost every grizzly bear in California had been tracked down and killed. In 1924, what was thought to be a grizzly was spotted in Sequoia National Park for the last time and thereafter, grizzlies were never seen again in California. Support to reintroduce grizzlies to
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