Lake Mohave is a reservoir on the Colorado River between the Hoover Dam and Davis Dam in Cottonwood Valley defining the border between Nevada and Arizona in the United States. This 67 mile stretch of the Colorado River flows past Boulder City, Searchlight, Cottonwood Cove, Cal-Nev-Ari, Laughlin to the west in Nevada and Willow Beach and Bullhead City to the east in Arizona. A maximum width of 4 miles wide and an elevation of 647 feet, Lake Mohave encompasses 28,260 acres of water; as Lake Mead lies to the north of the Hoover Dam, Lake Mohave and adjacent lands forming its shoreline are part of the Lake Mead National Recreation Area administered by the U. S. National Park Service. There are three resorts on Lake Mohave: Katherine Landing and Willow Beach in Arizona and Cottonwood Cove in Nevada. Katherine Landing and Cottonwood Cove resorts offer lodging, RV parks with utility hook-ups, campgrounds, a restaurant a store, marinas with gas docks. Popular recreational activities in Lake Mohave are swimming, fishing and skiing.
There are kayaking, scuba diving, fishing supplies in Bullhead City, which borders the southernmost point of Lake Mohave. Lake Mohave offers year-round recreational opportunities, its clear water caters to boaters and fishermen while its desert rewards hikers, wildlife photographers, roadside sightseers. It is home to thousands of desert plants and animals, adapted to survive in an extreme place where rain is scarce and temperatures soar. Lake Mead National Recreation Area, which encompasses Lake Mead, Lake Mohave and a portion of the Colorado River, offers good diving opportunities for both novice and advanced divers. At Lake Mohave, divers can explore Black Canyon. Advanced divers can check out Ringbolt Rapids. Work Barge on the Arizona side has a 38-foot tow barge that sank in 1946. Cabinsite Point has two boat wrecks to view. PWCs allowed to be operated within Lake Mead National Recreation Area, which encompasses Lake Mead and Lake Mohave, include any four-stroke, two-strokes meeting EPA 2006 emission standards.
As of December 31, 2012 many two-stroke personal watercraft are no longer allowed to operate within Lake Mead National Recreation Area. These include any PWC with a carbureted two-stroke engine. Enforcement began January 1, 2013 as part of a ten-year phase-in, based on the final rule to prohibit these PWCs being approved in April 2003; the volcanic origin of Black Canyon and Cottonwood Valley has resulted in a number of hot springs along the northern portion of Lake Mohave. Gold Strike Hot Springs is located close to the shore, accessible from a trailhead 1.2 miles south of the Hoover Dam. These springs are available from the Gold Strike Hot Springs Trail Head two miles east of the Hoover Dam in Boulder City, Nevada. Due to the easy two mile hike from public parking and consistent pools, these springs are visited. Two Mile Hot Springs and Arizona Hot Springs are within a few miles of this same area and offer a more private experience. Razorback sucker Bonytail chub Rainbow trout Largemouth bass Smallmouth bass Striped bass Crappie Sunfish Channel catfish Common carp Threadfin shad The non-native sport fishery in Lake Mohave is enhanced by a Nevada Division of Wildlife program which places artificial habitat bundles in coves around the reservoir.
The habitats are composed of bundled salt cedar trees attached to wooden pallets. When placed in the water, the structures create cover for sport fish. Additionally, Lake Mohave contains one of the largest and most genetically diverse population of razorback sucker remaining in the wild; each spring, a multi-agency group of fish biologists use underwater lights to collect 30,000 razorback sucker larvae along the shore of Lake Mohave, which would otherwise be eaten by introduced fishes. Larvae are transported by boat to Willow Beach National Fish Hatchery where they grow in protected raceways for up to three years; when individuals have reached 14 inches in length, they are released back into Lake Mohave in order to avoid predation by larger, introduced game fish such as striped bass. Katherine's Landing, Lake Mohave Cottonwood Basin National Park Service, Lake Mead National Recreation Area Daily data of level and flow from US Department of the Interior | Bureau of Reclamation | Lower Colorado Region Arizona Boating Locations Facilities Map Arizona Fishing Locations Map Cultural History of Lake Mohave
Casa Grande Ruins National Monument
Casa Grande Ruins National Monument, in Coolidge, just northeast of the city of Casa Grande, preserves a group of Ancient Pueblo Peoples Hohokam structures of the Pueblo III and Pueblo IV Eras. The national monument consists of the ruins of multiple structures surrounded by a compound wall constructed by the ancient people of the Hohokam period, who farmed the Gila Valley in the early 13th century. "Archeologists have discovered evidence that the ancient Sonoran Desert people who built the Casa Grande developed wide-scale irrigation farming and extensive trade connections which lasted over a thousand years until about 1450 C. E.""Casa Grande" is Spanish for "big house". The structure is made of caliche, has managed to survive the extreme weather conditions for about seven centuries; the large house consists of outer rooms surrounding an inner structure. The outer rooms are all three stories high; the structures were constructed using traditional adobe processes. The wet adobe adds significant strength.
Noticeable horizontal cracks define the breaks between courses on the thick outer walls. The process consisted of using damp adobe to form the walls and waiting for it to dry, building it up with more adobe. Casa Grande contained a ball court much like. Father Eusebio Kino was the first European to view the Hohokam complex in November 1694 and named it Casa Grande. Graffiti from 19th-century passers-by is scratched into its walls. Casa Grande now has a distinctive modern roof covering built in 1932. In 1891, the monument underwent repairs supervised by Cosmos Mindeleff of the Bureau of American Ethnology, until funds ran out. Proclaimed Casa Grande Reservation by Executive Order 28-A of President Benjamin Harrison on June 22, 1892, Casa Grande Ruins became the first prehistoric and cultural reserve in the US, it was re-designated a national monument by President Woodrow Wilson on August 3, 1918. As with all historical areas administered by the National Park Service, Casa Grande was listed on the National Register of Historic Places on October 15, 1966.
Between 1937 and 1940 the Civilian Conservation Corps built several adobe buildings to serve as housing and administrative offices for the national monument. The adobe buildings, constructed using traditional methods, continue in use today and are now listed on the National Register of Historic Places; because of careful conservation, the physical appearance of Casa Grande Ruins has hardly changed since the 1940s. In 1932, a ramada to shelter the ruins from weathering was built by Boston architect Frederick Law Olmsted, Jr. In the early 21st century, a pair of great horned owls took up residence in the rafters of the Olmsted shelter; the current protective structure covering the "Great House" replaced a wooden similar structure built to protect it in 1903. Due to the fragile nature of the "Great House," visitors to the site are not permitted inside. To protect its integrity, observation by visitors is only permitted outside the structure. Hohokam Pima National Monument Mesa Grande Oasisamerica cultures Pueblo Grande Ruin and Irrigation Sites Noble, David Grant.
Ancient Ruins of the Southwest'. Flagstaff, Arizona: Northland Publishing. ISBN 0-87358-530-5. "The National Parks: Index 2009–2011". National Park Service. Archived from the original on 2011-06-29. Retrieved 2011-06-29. National Park Service: official Casa Grande Ruins National Monument website Historic American Buildings Survey No. AZ-14, "Casa Grande, Pinal County, AZ", 2 photos, 4 data pages Casa Grande Ruin, by Cosmos Mindeleff at Project Gutenberg The Repair Of Casa Grande Ruin, Arizona, in 1891, by Cosmos Mindeleff at Project Gutenberg "Casa Grande Ruins National Monument". Discover Our Shared Heritage: American Southwest. National Park Service. Retrieved 2011-06-29
The Mojave Desert is an arid rain-shadow desert and the driest desert in North America. It is in the southwestern United States within southeastern California and southern Nevada, it occupies 47,877 sq mi. Small areas extend into Utah and Arizona, its boundaries are noted by the presence of Joshua trees, which are native only to the Mojave Desert and are considered an indicator species, it is believed to support an additional 1,750 to 2,000 species of plants. The central part of the desert is sparsely populated, while its peripheries support large communities such as Las Vegas, Lancaster, Victorville, St. George; the Mojave Desert is bordered by the Great Basin Desert to its north and the Sonoran Desert to its south and east. Topographical boundaries include the Tehachapi Mountains to the west, the San Gabriel Mountains and San Bernardino Mountains to the south; the mountain boundaries are distinct because they are outlined by the two largest faults in California – the San Andreas and Garlock faults.
The Mojave Desert displays typical range topography. Higher elevations above 2,000 ft in the Mojave are referred to as the High Desert; the Mojave Desert occupies less than 50,000 sq mi, making it the smallest of the North American deserts. The Mojave Desert is referred to as the "high desert", in contrast to the "low desert", the Sonoran Desert to the south; the Mojave Desert, however, is lower than the Great Basin Desert to the north. The spelling Mojave originates from the Spanish language while the spelling Mohave comes from modern English. Both are used today, although the Mojave Tribal Nation uses the spelling Mojave; the Mojave Desert receives less than 2 inches of rain a year and is between 2,000 and 5,000 feet in elevation. The Mojave Desert contains the Mojave National Preserve, as well as the lowest and hottest place in North America: Death Valley at 282 ft below sea level, where the temperature surpasses 120 °F from late June to early August. Zion National Park in Utah lies at the junction of the Mojave, the Great Basin Desert, the Colorado Plateau.
Despite its aridity, the Mojave has long been a center of alfalfa production, fed by irrigation coming from groundwater and from the California Aqueduct. The Mojave is a desert of two distinct seasons. Winter months bring comfortable daytime temperatures, which drop to around 25 °F on valley floors, below 0 °F at the highest elevations. Storms moving from the Pacific Northwest can bring rain and in some places snow. More the rain shadow created by the Sierra Nevada as well as mountain ranges within the desert such as the Spring Mountains, bring only clouds and wind. In longer periods between storm systems, winter temperatures in valleys can approach 80 °F. Spring weather continues to be influenced by Pacific storms, but rainfall is more widespread and occurs less after April. By early June, it is rare for another Pacific storm to have a significant impact on the region's weather. Summer weather is dominated by heat. Temperatures on valley floors can soar above 130 °F at the lowest elevations. Low humidity, high temperatures, low pressure, draw in moisture from the Gulf of Mexico creating thunderstorms across the desert southwest known as the North American monsoon.
While the Mojave does not get nearly the amount of rainfall the Sonoran desert to the south receives, monsoonal moisture will create thunderstorms as far west as California's Central Valley from mid-June through early September. Autumn is pleasant, with one to two Pacific storm systems creating regional rain events. October is one of the sunniest months in the Mojave. After temperature, wind is the most significant weather phenomenon in the Mojave. Across the region windy days are common. During the June Gloom, cooler air can be pushed into the desert from Southern California. In Santa Ana wind events, hot air from the desert blows into the Los Angeles basin and other coastal areas. Wind farms in these areas generate power from these winds; the other major weather factor in the region is elevation. The highest peak within the Mojave is Charleston Peak at 11,918 feet, while the Badwater Basin in Death Valley is 279 feet below sea level. Accordingly and precipitation ranges wildly in all seasons across the region.
The Mojave Desert has not supported a fire regime because of low fuel loads and connectivity. However, in the last few decades, invasive annual plants such as some within the genera Bromus and Brassica have facilitated fire; this has altered many areas of the desert. At higher elevations, fire regimes are infrequent; the Mojave Desert is defined by numerous mountain ranges creating its xeric conditions. These ranges create valleys, endorheic basins, salt pans, seasonal saline lakes when precipitation is high enough. These
National Historic Site (United States)
National Historic Site is a designation for an recognized area of national historic significance in the United States. An NHS contains a single historical feature directly associated with its subject. A related but separate designation, the National Historical Park, is an area that extends beyond single properties or buildings, its resources include a mix of historic and sometimes significant natural features; as of 2018, there are 89 NHSs. Most NHPs and NHSs are managed by the National Park Service; some federally designated sites are owned by local authorities or owned, but are authorized to request assistance from the NPS as affiliated areas. One property, Grey Towers National Historic Site, is managed by the U. S. Forest Service; as of October 15, 1966, all historic areas, including NHPs and NHSs, in the NPS are automatically listed on the National Register of Historic Places. There are about 90,000 NRHP sites, the large majority of which are neither owned nor managed by the NPS. Of these, about 2,500 have been designated at the highest status as National Historic Landmark sites.
National Historic Sites are federally owned and administered properties, though some remain under private or local government ownership. There are 89 NHSs, of which 77 are official NPS units, 11 are NPS affiliated areas, 1 is managed by the US Forest Service. Derived from the Historic Sites Act of 1935, a number of NHSs were established by United States Secretaries of the Interior, but most have been authorized by acts of Congress. In 1937, the first NHS was created in Salem, Massachusetts in order to preserve and interpret the maritime history of New England and the United States. There is one International Historic Site in the US park system, a unique designation given to Saint Croix Island, Maine, on the New Brunswick border; the title, given to the site of the first permanent French settlement in America, recognizes the influence that has had on both Canada and the United States. The NPS does not distinguish among these designations in terms of their preservation or management policies. In the United States, sites are "historic", while parks are "historical".
The NPS explains that a site can be intrinsically historic, while a park is a modern legal invention. As such, a park is not itself "historic", but can be called "historical" when it contains historic resources, it is the resources. Klondike Gold Rush International Historical Park was formally established in 1998 by the United States and Canada, the year of the centennial of the gold rush the park commemorates; the park comprises Klondike Gold Rush National Historical Park in Washington and Alaska, Chilkoot Trail National Historic Site in British Columbia. It was this trail which so many prospectors took in hopes of making their fortunes in the Klondike River district of Yukon. National Historic Sites List of World Heritage Sites in North America Designation of National Park System Units
Davis Dam is a dam on the Colorado River about 70 miles downstream from Hoover Dam. It stretches across the border between Nevada. Called Bullhead Dam, Davis Dam was renamed after Arthur Powell Davis, the director of the U. S. Bureau of Reclamation from 1914 to 1923; the United States Bureau of Reclamation owns and operates the dam, completed in 1951. Davis Dam forms Lake Mohave. Davis DamDavis Dam is a zoned earth-fill dam with a concrete spillway, 1,600 ft in length at the crest, 200 ft high; the earth fill dam begins on the Nevada side, but it does not extend to the Arizona side on the east. Instead, there is an inlet formed by concrete, that includes the spillway; the hydroelectric power plant is beside the inlet. The dam's purpose is to re-regulate releases from Hoover Dam upstream, facilitate the delivery of Colorado River water to Mexico. Bullhead City and Laughlin, are located just below the dam along the river. Davis Camp is nearby. Bullhead City was a construction town for workers building the dam.
A road is located on the crest of the earth fill portion of the dam and a Forebay Bridge spans the Forebay. It was part of Arizona State Route 68 to Nevada. In April 2004, the roadway was shut down to vehicle traffic. Pedestrian and bicycle traffic are permitted; the old roadway is now an extension of the Heritage Trail system. Barriers have been placed on the former road at each end of the earthen dam; the facility is patrolled by security forces who enforce parking regulations. Davis Dam Hydroelectric Power PlantThe Davis Dam Power Plant is a hydroelectric power plant located on the Arizona side of the dam, beside the inlet; the hydroelectric plant generates between 2 terawatt-hours of electricity annually. The plant has a capacity of 251 MW and the tops of its five Francis turbines are visible from outside the plant; the plant's head is 136 ft. Dams of the Lower Colorado River Valley Bullhead City, Arizona Laughlin, Nevada List of power stations in the United States USBR - Davis Dam USBR - Davis Power Plant USBR - Parker-Davis Project USGS - Real Time Water Data Historic American Engineering Record No.
AZ-77, "Davis Dam" HAER No. AZ-77-A, "Davis Dam, Switchyards"
International Union for Conservation of Nature
The International Union for Conservation of Nature is an international organization working in the field of nature conservation and sustainable use of natural resources. It is involved in data gathering and analysis, field projects and education. IUCN's mission is to "influence and assist societies throughout the world to conserve nature and to ensure that any use of natural resources is equitable and ecologically sustainable". Over the past decades, IUCN has widened its focus beyond conservation ecology and now incorporates issues related to sustainable development in its projects. Unlike many other international environmental organisations, IUCN does not itself aim to mobilize the public in support of nature conservation, it tries to influence the actions of governments and other stakeholders by providing information and advice, through building partnerships. The organization is best known to the wider public for compiling and publishing the IUCN Red List of Threatened Species, which assesses the conservation status of species worldwide.
IUCN has a membership of over 1400 non-governmental organizations. Some 16,000 scientists and experts participate in the work of IUCN commissions on a voluntary basis, it employs 1000 full-time staff in more than 50 countries. Its headquarters are in Switzerland. IUCN has observer and consultative status at the United Nations, plays a role in the implementation of several international conventions on nature conservation and biodiversity, it was involved in establishing the World Wide Fund for Nature and the World Conservation Monitoring Centre. In the past, IUCN has been criticized for placing the interests of nature over those of indigenous peoples. In recent years, its closer relations with the business sector have caused controversy. IUCN was established in 1948, it was called the International Union for the Protection of Nature and the World Conservation Union. Establishment IUCN was established on 5 October 1948, in Fontainebleau, when representatives of governments and conservation organizations signed a formal act constituting the International Union for the Protection of Nature.
The initiative to set up the new organisation came from UNESCO and from its first Director General, the British biologist Julian Huxley. The objectives of the new Union were to encourage international cooperation in the protection of nature, to promote national and international action and to compile and distribute information. At the time of its founding IUPN was the only international organisation focusing on the entire spectrum of nature conservation Early years: 1948–1956 IUPN started out with 65 members, its secretariat was located in Brussels. Its first work program focused on saving species and habitats and applying knowledge, advancing education, promoting international agreements and promoting conservation. Providing a solid scientific base for conservation action was the heart of all activities. IUPN and UNESCO were associated, they jointly organized the 1949 Conference on Protection of Nature. In preparation for this conference a list of gravely endangered species was drawn up for the first time, a precursor of the IUCN Red List of Threatened Species.
In the early years of its existence IUCN depended entirely on UNESCO funding and was forced to temporarily scale down activities when this ended unexpectedly in 1954. IUPN was successful in engaging prominent scientists and identifying important issues such as the harmful effects of pesticides on wildlife but not many of the ideas it developed were turned into action; this was caused by unwillingness to act on the part of governments, uncertainty about the IUPN mandate and lack of resources. In 1956, IUPN changed its name to International Union for Conservation of Nature and Natural Resources. Increased profile and recognition: 1956–1965 In the 1950s and 1960s Europe entered a period of economic growth and formal colonies became independent. Both developments had impact on the work of IUCN. Through the voluntary involvement of experts in its Commissions IUCN was able to get a lot of work done while still operating on a low budget, it established links with the Council of Europe. In 1961, at the request of United Nations Economic and Social Council, the United Nations Economic and Social Council, IUCN published the first global list of national parks and protected areas which it has updated since.
IUCN's best known publication, the Red Data Book on the conservation status of species, was first published in 1964. IUCN began to play a part in the development of international treaties and conventions, starting with the African Convention on the Conservation of Nature and Natural Resources. Environmental law and policy making became a new area of expertise. Africa was the focus of many of the early IUCN conservation field projects. IUCN supported the ‘Yellowstone model’ of protected area management, which restricted human presence and activity in order to protect nature. IUCN and other conservation organisations were criticized for protecting nature against people rather than with people; this model was also applied in Africa and played a role in the decision to remove the Maasai people from Serengeti National Park and the Ngorongoro Conservation Area. To establish a stable financial basis for its work, IUCN participated in setting up the World Wildlife Fund
Hoover Dam is a concrete arch-gravity dam in the Black Canyon of the Colorado River, on the border between the U. S. states of Nevada and Arizona. It was constructed between 1931 and 1936 during the Great Depression and was dedicated on September 30, 1935, by President Franklin D. Roosevelt, its construction was the result of a massive effort involving thousands of workers, cost over one hundred lives. Known as Boulder Dam from 1933, it was renamed Hoover Dam, for President Herbert Hoover, by a joint resolution of Congress in 1947. Since about 1900, the Black Canyon and nearby Boulder Canyon had been investigated for their potential to support a dam that would control floods, provide irrigation water and produce hydroelectric power. In 1928, Congress authorized the project; the winning bid to build the dam was submitted by a consortium called Six Companies, Inc. which began construction on the dam in early 1931. Such a large concrete structure had never been built before, some of the techniques were unproven.
The torrid summer weather and lack of facilities near the site presented difficulties. Six Companies turned the dam over to the federal government on March 1, 1936, more than two years ahead of schedule. Hoover Dam impounds the largest reservoir in the United States by volume; the dam is located near Boulder City, Nevada, a municipality constructed for workers on the construction project, about 30 mi southeast of Las Vegas, Nevada. The dam's generators provide power for public and private utilities in Nevada and California. Hoover Dam is a major tourist attraction; the traveled U. S. Route 93 ran along the dam's crest until October 2010; as the United States developed the Southwest, the Colorado River was seen as a potential source of irrigation water. An initial attempt at diverting the river for irrigation purposes occurred in the late 1890s, when land speculator William Beatty built the Alamo Canal just north of the Mexican border. Though water from the Imperial Canal allowed for the widespread settlement of the valley, the canal proved expensive to maintain.
After a catastrophic breach that caused the Colorado River to fill the Salton Sea, the Southern Pacific Railroad spent $3 million in 1906–07 to stabilize the waterway, an amount it hoped in vain would be reimbursed by the Federal Government. After the waterway was stabilized, it proved unsatisfactory because of constant disputes with landowners on the Mexican side of the border; as the technology of electric power transmission improved, the Lower Colorado was considered for its hydroelectric-power potential. In 1902, the Edison Electric Company of Los Angeles surveyed the river in the hope of building a 40-foot rock dam which could generate 10,000 horsepower. However, at the time, the limit of transmission of electric power was 80 miles, there were few customers within that limit. Edison allowed land options it held on the river to lapse—including an option for what became the site of Hoover Dam. In the following years, the Bureau of Reclamation, known as the Reclamation Service at the time considered the Lower Colorado as the site for a dam.
Service chief Arthur Powell Davis proposed using dynamite to collapse the walls of Boulder Canyon, 20 miles north of the eventual dam site, into the river. The river would carry off the smaller pieces of debris, a dam would be built incorporating the remaining rubble. In 1922, after considering it for several years, the Reclamation Service rejected the proposal, citing doubts about the unproven technique and questions as to whether it would in fact save money. In 1922, the Reclamation Service presented a report calling for the development of a dam on the Colorado River for flood control and electric power generation; the report was principally authored by Davis, was called the Fall-Davis report after Interior Secretary Albert Fall. The Fall-Davis report cited use of the Colorado River as a federal concern because the river's basin covered several states, the river entered Mexico. Though the Fall-Davis report called for a dam "at or near Boulder Canyon", the Reclamation Service found that canyon unsuitable.
One potential site at Boulder Canyon was bisected by a geologic fault. The Service found it ideal. Despite the site change, the dam project was referred to as the "Boulder Canyon Project". With little guidance on water allocation from the Supreme Court, proponents of the dam feared endless litigation. A Colorado attorney proposed that the seven states which fell within the river's basin form an interstate compact, with the approval of Congress; such compacts were authorized by Article I of the United States Constitution but had never been concluded among more than two states. In 1922, representatives of seven states met with then-Secretary of Commerce Herbert Hoover. Initial talks produced no result, but when the Supreme Court handed down the Wyoming v. Colorado decision undermining the claims of the upstream states, they became anxious to reach an agreement; the resulting Colorado River Compact was signed on November 24, 1922. Legislation to authorize the dam was introduced by two California Republicans, Representative Phi