Misplaced Pages

#281718

55-546: Lake Powell was created by the flooding of Glen Canyon by the Glen Canyon Dam , which also led to the 1972 creation of Glen Canyon National Recreation Area , a popular summer destination of public land managed by the National Park Service . The reservoir is named for John Wesley Powell , a civil war veteran who explored the river via three wooden boats in 1869. It lies primarily in southern Utah, with

110-593: A houseboat or bring their own camping equipment, find a secluded spot somewhere in the canyons, and make their own camp (there are no restrictions on where visitors can stay). The Castle Rock Cut is one of the most important navigational channels in the lake; it was blasted as early as the 1970s to allow boaters to bypass the winding canyons between the Glen Canyon Dam and reaches of Lake Powell further upstream – saving, on average, one hour of travel time. The cut has been deepened several times since then, to allow

165-617: A costly and time-consuming problem for water managers in the West. Control policies have recently been introduced to alleviate the hydroelectric problems as well as ecological problems faced by Western infestation. Beginning in 1999 Lake Powell began to visually monitor for the mussels. In 2001 hot water boat decontamination sites were established at Wahweap, Bullfrog, and Halls Crossing marinas. In January 2007, zebra mussels were detected in Lake Mead and new action plans were announced to prevent

220-554: A major barrier to early settlers and explorers of the region. In 1880 a prospector named Cass Hite established a ford near the mouth of the Dirty Devil River , 2 miles (3.2 km) downstream from the present-day bridge location. This ford, named "Dandy Crossing", served as one of the few locations in the region where travelers could cross the Colorado River. The settlement that formed at the crossing location took

275-615: A mussel certificate, although boat owners were allowed to self-certify. These measures were intended to help prevent vessels from transporting Zebra mussels into Lake Powell. Despite these measures, quagga mussel DNA was detected in 2012 and live mussels were found at a number of sites including the Wahweap Marina in Spring and Summer 2013. In June 2013 the NPS was attempting a diver-based eradication program to find and remove mussels before

330-626: A savings of 300,000 acre feet of water or more per year, leading to calls by environmentalists to drain Lake Powell and restore Glen Canyon to its natural, free-flowing state. These data are for the Wahweap climate station on Lake Powell just south of the Utah-Arizona border (Years 1961 to 2012). Glen Canyon was carved by differential erosion from the Colorado River over an estimated 5 million years. The Colorado Plateau , through which

385-606: A small portion in northern Arizona. Lake Powell is a water storage facility for the Upper Basin states of the Colorado River Compact ( Colorado , Utah , Wyoming and New Mexico ). The Compact specifies that the Upper Basin states are to provide a minimum annual flow of 7,500,000 acre-feet (9.3 km) to the Lower Basin states (Arizona, Nevada, and California). According to US Geological Survey and

440-494: Is an arch bridge that carries Utah State Route 95 across the Colorado River northwest of Blanding, Utah , United States . The bridge informally marks the upstream limit of Lake Powell and the end of Cataract Canyon of the Colorado River, but when the lake is at normal water elevation, the water can back up over 30 miles (48 km) upstream into Cataract Canyon. The bridge is the only automobile bridge spanning

495-560: Is at Lee's Ferry , Arizona; the numbers increase as one travels upstream, ending at Mile 169.6 at the confluence with the Dirty Devil River . In the 1950s, with the proposal of a dam upstream of the Grand Canyon for water storage and hydroelectric power generation, many environmentalist groups rallied to prevent the inundation of the largely undeveloped canyons in the upper Colorado River watershed. The Sierra Club and many other conservation organizations were instrumental in blocking

550-467: Is part of the immense system of canyons carved by the Colorado River and its tributaries. In 1963, a reservoir , Lake Powell , was created by the construction of the Glen Canyon Dam , in the Arizona portion of Glen Canyon near the brand new town of Page , inundating much of Glen Canyon under water hundreds of feet in depth. Contrary to popular belief, Lake Powell was not the result of negotiations over

605-590: The Colorado River , mostly in southeastern and south-central Utah , in the United States. Glen Canyon starts where Narrow Canyon ends, at the confluence of the Colorado River and the Dirty Devil River . A small part of the lower end of Glen Canyon extends into northern Arizona and terminates at Lee's Ferry , near the Vermilion Cliffs . Like the Grand Canyon farther downstream, Glen Canyon

SECTION 10

#1732766150282

660-752: The Cummings Mesa , farmed the Lower Glen Canyon on a seasonal basis, and gathered raw materials. To prove this thesis of seasonal habitation, criteria such as architectural units, locations of trail systems, occurrence of ceremonial structures, prevalence of burials, and position of natural and cultural strata were investigated. Four types of sites are described in the survey, classified as either open sites situated on rock terraces; talus sites on broken material below cliffs; shelter sites in protected areas under overhanging cliffs; and cliff sites beneath ledges or in caves and canyon walls. Open sites are

715-656: The Flaming Gorge Reservoir in July 2021. and by April 22, 2022, Lake Powell was at 3,522.24 feet (1,073.58 m) in elevation – just 22.88% of capacity. This marks the lowest water level for Lake Powell since it was filled in 1963. The capacity of Lake Powell has decreased by 7% since 1963 facing an average annual loss of 33,270 acre-feet of storage, due to the inflow of sediments from Colorado and San Juan rivers. Peer-reviewed studies indicate that storing water in Lake Mead rather than in Lake Powell would yield

770-480: The Grand Canyon . American writer Edward Abbey also documented his experience exploring Glen Canyon from the Colorado River prior to the completion of Glen Canyon Dam in his 1968 memoir Desert Solitaire , in the chapter titled "Down the River". 37°15′15″N 110°52′42″W  /  37.25417°N 110.87833°W  / 37.25417; -110.87833 Hite Crossing Bridge The Hite Crossing Bridge

825-718: The Kaiparowits Plateau and San Rafael Swell to the north of the lake. The confluences of the Escalante , Dirty Devil and San Juan rivers with the Colorado lie within Lake Powell. The slower flow of the San Juan river has produced goosenecks where 5 miles (8.0 km) of river are contained within 1-mile (1.6 km) on a straight line. The lake's main body stretches up Glen Canyon, but has also filled many (over 90) side canyons. The lake also stretches up

880-523: The Sierra Club , succeeded in defeating the Bureau's bid, citing Echo Park's natural and scenic qualities as too valuable to submerge. Glen Canyon Dam was built to solve the downstream delivery obligations of the Upper Basin states. Lake Powell is an "aquatic bank" built to fulfill the terms of the "Compact Calls" of Lower Basin. Construction on Glen Canyon Dam began with a demolition blast keyed by

935-603: The fractal nature of the lake's hydrologic surface area can allow vessels with limited charting equipment to become easily lost. The burying of human (and pet) waste in Glen Canyon National Recreation Area is prohibited. Anyone who camps farther than a quarter of a mile from a marina must bring a portable toilet . Pet waste must also be packed out. The southwestern end of Lake Powell in Arizona can be accessed via U.S. Route 89 and State Route 98 . State Route 95 and State Route 276 lead to

990-587: The 1830s, trapper Denis Julien may have visited upper Glen Canyon by boat. In 1869 and again in 1871, scientific expeditions led by John Wesley Powell traveled through Glen Canyon en route to the Grand Canyon, resulting in the first formal surveys of the main channel and many of the side canyons. In the 1890s, hundreds of miners panned for flour gold in Glen Canyon. Their main camp was at Dandy Crossing, also called Hite, Utah , after Cass Hite. Between 1898 and 1901, mining engineer Robert Brewster Stanton

1045-544: The 1940s and early 1950s, the United States Bureau of Reclamation planned to construct a series of Colorado River dams in the rugged Colorado Plateau province of Colorado, Utah, and Arizona. Glen Canyon Dam was born of a controversial damsite the Bureau selected in Echo Park , in what is now Dinosaur National Monument in Colorado. A small but politically effective group of objectors, led by David Brower of

1100-555: The Bureau of Reclamation report, in addition to water loss, Lake Powell faced an average annual loss in storage capacity of about 33,270 acre-feet, or 11 billion gallons, per year between 1963 and 2018 because of sediments flowing in from the Colorado and San Juan rivers. Those settle at the bottom of the reservoir and decrease the total amount of water the reservoir can hold. Environmentalists have pushed to drain Lake Powell and restore Glen Canyon to its natural, free-flowing state. In

1155-479: The Colorado River began to back up, no longer being diverted through the tunnels. The newly flooded Glen Canyon formed Lake Powell. Sixteen years elapsed before the lake filled to the 3,700 feet (1,100 m) level on June 22, 1980. The lake level fluctuates considerably depending on the seasonal snow runoff from the Rocky Mountains. The all-time highest water level was reached on July 14, 1983, during one of

SECTION 20

#1732766150282

1210-487: The Colorado River between the Glen Canyon Bridge, 185 miles (298 km) downstream near the Glen Canyon Dam and the U.S. Route 191 bridge 110 miles (180 km) upstream near Moab . The bridge is near Hite Marina on Lake Powell, and a small airstrip is immediately adjacent to the north side of the bridge. The American Discovery Trail uses the bridge to cross the Colorado. The Colorado River served as

1265-555: The Colorado River through the canyon and realized the tremendous resource it was. The experience transformed Brower's attitude towards environmental preservation, making him more radical and less likely to compromise. His experience has been compared to the experience of John Muir with the Hetch Hetchy Reservoir in California. For Brower, it steeled him for the 1960s battle over the proposed Marble Canyon Dam in

1320-401: The Colorado River. By April 9, 2014, the lake level had fallen to 3,574.31 feet (1,089.45 m), largely erasing the gains made in 2011. Colorado River levels returned to normal during water years 2014 and 2015 (pushing the lake to 3,606 feet (1,099 m)) by the end of water year 2015. The Bureau of Reclamation in 2014 reduced the Lake Powell release from 8.23 to 7.48 million acre-feet, for

1375-758: The Escalante River and San Juan River where they merge into the main Colorado River. This provides access to many natural geographic points of interest as well as some remnants of the Anasazi culture. Access to the lake is limited to developed marinas because most of the lake is surrounded by steep sandstone walls: The following marinas are accessible only by boat: Glen Canyon National Recreation Area draws more than two million visitors annually. Recreational activities include boating , fishing , waterskiing , jet-skiing , and hiking. Prepared campgrounds can be found at each marina, but many visitors choose to rent

1430-472: The Rincon. Both formations are the result of the ancient inland sea that covered the area. Once the sea drained, windblown sand invaded the area, creating what is known as Wingate Sandstone . The more recent ( Jurassic Period ) formations include Kayenta Sandstone , which produces the trademark blue-black "desert varnish" that streaks down many walls of the canyons. Above this is Navajo Sandstone . Many of

1485-587: The U.S. Department of the Interior within Glen Canyon National Recreation Area . Studies indicate a chronology for the Lower Glen Canyon prehistory, "from pre-A.D. 1 to the 15th century and recorded history from 1776 to the present". Most of the ceramic material found in the main canyon was probably made in the highlands, although it is possible some pottery was manufactured in Lower Glen Canyon. Clay deposits are found along

1540-495: The arches, including Rainbow Bridge, lie at this transition point. This period also includes light yellow Entrada Sandstone , and the dark brown, almost purple Carmel Formation . These latter two can be seen on the tops of mesas around Wahweap , and the crown of Castle Rock and Tower Butte . Above these layers lie the sandstone , conglomerate and shale of the Straight Cliffs Formation that underlies

1595-595: The ballast water of ships entering the Great Lakes. These aquatic invaders soon spread to many bodies of water in the Eastern United States and have even made their way to the western United States. In January 2008, Zebra mussels have been detected in several reservoirs along the Colorado River system such as Lakes Mead, Mojave, and Havasu. By the early 2000s Arizona , California , Nebraska , Kansas , Colorado , Nevada and Utah have all confirmed

1650-533: The canyon cuts, arose some 11 million years ago. Within that plateau lie layers of rock from over 300 million years ago to the relatively recent volcanic activity. Pennsylvanian and Permian formations can be seen in Cataract Canyon and San Juan Canyon . The Moenkopi Formation , which dates from 230 million years ago ( Triassic Period ), and the Chinle Formation are found at Lees Ferry and

1705-517: The clock on June 17, 1960. The last bucket of over 5 million cubic yards (4,000,000 m) was poured on September 13, 1963. The dam is 710 feet (216 m) high and the surface elevation of the water at full-pool is approximately 3700 feet (1100 m). Construction cost $ 155 million, and 18 lives were lost. On September 22, 1966, Glen Canyon Dam was dedicated by Lady Bird Johnson . From 1970 to 1980, turbines and generators were installed for hydroelectricity. Upon completion of Glen Canyon Dam on September 13, 1963,

Lake Powell - Misplaced Pages Continue

1760-687: The controversial damming of the Green River within Dinosaur National Monument at Echo Park ; the Echo Park Dam proposal was abandoned due to nationwide citizen pressure on Congress to do so. The Glen Canyon Dam remains a central issue for modern environmentalist movements. Beginning in the late 1990s, the Sierra Club and other organizations renewed the call to dismantle the dam and drain Lake Powell in Lower Glen Canyon. Today, Glen Canyon and Lake Powell are managed by

1815-568: The entire Glen Canyon region, perhaps one of the major reasons for occupation". Cryptocrystalline rocks fill the Pleistocene gravel beds on the Carmel platforms. Scattered lithic tools and materials indicate workshops of various sizes. There is a lack of siliceous material in the highlands, but tools are found there made from the gravel beds in the river. There are very few ground stone artifacts, such as manos, metates, and scrapers, found in

1870-448: The first time since the lake filled in 1980. This was done due to the "equalization" guideline which stipulates that an approximately equal amount of water must be retained in both Lake Powell and Lake Mead , in order to preserve hydro-power generation capacity at both lakes. This resulted in Lake Mead declining to the lowest level on record since the 1930s. Long-term water level decline continued, forcing an emergency release of water from

1925-478: The heaviest Colorado River floods in recorded history, in part influenced by a strong El Niño event . The lake rose to 3,708.34 feet (1,130.30 m) above sea level, with a water content of 25,757,086 acre-feet (31.770898 km). It lies primarily in parts of Garfield , Kane , and San Juan counties in southern Utah, with a small portion in Coconino County in northern Arizona. The northern limits of

1980-444: The highlands, granaries were near or incorporated into permanent pueblos, compared with smaller ones near temporary sites in the canyon. "Home Base" pueblos in the nearby highlands on Cummings Mesa and Paiute Mesa are believed to have supported temporary farming and hunting parties, who used an extensive trail system in the main canyon which is still in use today. "Stone tool manufacturing appears to have been an important industry for

2035-487: The lake became infested. The Washington County Water Conservancy District has proposed building the Lake Powell Pipeline , which would have the capacity to extract up to 83,756 acre-feet (103,312,000 m) per year from Lake Powell for distribution to municipal drinking water systems in the county. Glen Canyon Glen Canyon is a natural canyon carved by a 169.6-mile (272.9 km) length of

2090-519: The lake extend at least as far as the Hite Crossing Bridge . Colorado River flows have been below average since 2000 as a result of the southwestern North American megadrought , leading to lower lake levels. In winter 2005 (before the spring run-off) the lake reached its then-lowest level since filling, an elevation of 3,555.10 feet (1,083.59 m) above sea level, which was approximately 150 feet (46 m) below full pool. After 2005,

2145-407: The lake level slowly rebounded, although it has not filled completely since then. Summer 2011 saw the third largest June and the second largest July runoff since the closure of Glen Canyon Dam, and the water level peaked at nearly 3,661 feet (1,116 m), 77 percent of capacity, on July 30. However, water years 2012 and 2013 were, respectively, the third and fourth-lowest runoff years recorded on

2200-592: The level of Lake Powell was 45 feet below the bottom of the Castle Rock cut. Currently, most marinas on the lake don't have Automatic Identification System monitoring stations that transmit boat positions to the AIS websites for the boating community. A substantial number of vessels on the lake do not have AIS transponders as there currently are no mandatory requirements for AIS usage for this body of water. Extra precautions must be taken with respect to boating safety, as

2255-610: The main canyon, since these tools are mainly found in the highlands. In the main canyon, a large number of chipped implements, ranging from small arrowheads to large knives, are found. Finished tools, and possibly blanks taken to the mesa, were probably used for trade. Around 1956, archaeologists and biologists from the University of Utah and the Museum of Northern Arizona including Gene Field Foster , using National Park research grants, planned an emergency survey of Glen Canyon, which

Lake Powell - Misplaced Pages Continue

2310-421: The main lower canyon, and no formalized fields are found in the main canyon because of alleviation and slope wash burying. Houses, when found, are mostly sandstone slab with mortar, having one to seven rooms. "Well constructed mealing bins which usually denote permanency were lacking in the Lower Glen Canyon. In contrast, on Cummings Mesa at Surprise Pueblo, there was one entire room devoted to mealing bins…". In

2365-782: The majority on both sides of the river. The majority of sites, mostly Navajo camps, feature lithic garbage or ceramics, or both. Talus sites are rarely recorded. Most of the cultural remains found are chipped stone tools (lithic materials), including projectile points, scrapers, drills, knives, choppers, and ground stone tools and manos (grinders). The collection of sherds are mostly Tusayan Gray Ware and Tusayan White Ware. Petroglyph panels are found throughout Glen Canyon. "Pecked and incised figures depict mountain sheep, human figures, birds, human handprints and animal tracks. Geometric figures range from circles and spirals to highly complex rectilinear patterns. The human figures have triangular bodies. Painted figures have been reported for both sides of

2420-469: The name of its founder, Hite. In 1946, a settler named Arthur Chaffin constructed an automobile ferry using an old car engine and a thick steel cable to hold it in place. The ferry operated for 20 years, before the rising waters of Lake Powell inundated the settlement of Hite. The bridge was completed as part of the realignment of State Route 95, which was approved in 1962 due to the construction of Glen Canyon Dam and Lake Powell's subsequent flooding of

2475-605: The northeastern end of the lake in Utah. Some of these fish species are on the US Endangered Species List. Currently most native species on the Colorado River Basin are subject to ongoing restoration efforts of some kind. Bass Carp, pike and others Zebra and quagga mussels first appeared in the United States in the 1980s. The mussels were initially brought to the United States through

2530-476: The presence of larval zebra mussels in lakes and reservoirs. Zebra and quagga mussels can be destructive to an ecosystem due to competition for resources with native species. The filtration of zooplankton by the mussels can negatively impact the feeding for some species of fish. Zebra and quagga mussels can attach to hard surfaces and build layers on underwater structures. The mussels are known to clog pipes including those in hydroelectric power systems, thus becoming

2585-552: The proposed Echo Park Dam in Dinosaur National Monument . While Flaming Gorge Dam was built as an alternative to the proposed Echo Park and Split Mountain dams within Dinosaur National Monument, Glen Canyon lacked any protection as either a National Park or Monument. Without that protection, Glen Canyon Dam was authorized and constructed. In 1962, the Sierra Club's David Brower and many others floated

2640-496: The push of a button by President Dwight D. Eisenhower at his desk in the Oval Office on October 1, 1956, which started clearing tunnels for water diversion. On February 11, 1959, water flowed through the tunnels so dam construction could begin. Later that year, the bridge was completed, allowing trucks to deliver equipment and materials for the dam and also for the new town of Page, Arizona . Concrete placement started around

2695-541: The right bank of the Colorado. Basketmaker II is characterized by a lack of pottery, as well as above-ground and underground cists lined with slabs. There is very little evidence of permanent occupation except at Talus Ruin, a small pueblo with a kiva , a ceremonial structure, made mostly of masonry, featuring jacal walls of sticks and reeds set in mortar in a single row of masonry. The presence of metates are evidence that campsites with slab-lined hearths were inhabited for longer periods. Agricultural structures are not found in

2750-615: The river, and some crude pottery specimens may have been made there. Only four burials were found in Lower Glen Canyon at three sites. Trash dumps are not very common at most sites. This is more evidence to suggest the seasonal rather than permanent occupation of hunters and farmers in the canyon. Cultural similarities are based on the presence or absence of certain types of ceramic wares. Group types of pottery, including Kayenta (Tusayan and Tsegi Orange Ware), Virgin (San Juan Red and White Wares), with Fremont , and Mesa Verde or Anasazi types of White and Desert Gray Ware, were found mostly on

2805-585: The river.... Petroglyph panels of such quality are lacking from the highland regions adjacent to Glen Canyon". The recorded history of the canyon begins with the Dominguez–Escalante expedition in 1776, during which Spanish explorers first documented the existence of Glen Canyon. The expedition members crossed the Colorado River in Glen Canyon at the site now known as the Crossing of the Fathers . In

SECTION 50

#1732766150282

2860-511: The spread of mussels to Lake Powell. In August 2007, preliminary testing was positive for zebra or quagga larvae in Lake Powell. These tests were deemed false positives, but adult quagga mussels were found in 2013. In August 2010, Lake Powell was declared mussel free. Lake Powell introduced a mandatory boat inspection for each watercraft entering the reservoir beginning in June 2009. Effective June 29, 2009, every vessel entering Lake Powell must have

2915-543: The use of the channel during droughts. During the protracted 21st-century drought, however, the lake has dropped so quickly on several occasions that the cut dried up during the summer tourist season, most recently in 2013. Continued deepening of the Castle Rock cut has been criticized for its high cost, but boaters and the National Park Service argue that it improves safety, saves millions of dollars in fuel, and improves emergency response time. In September 2021

2970-493: Was employed by mining magnate Julius Stone to design, build, and operate a dredge in an attempt to recover Glen Canyon's flour gold. The effort failed. The following is a list of geographical and cultural features along the Colorado River in Glen Canyon. Many of these locations are now partially or entirely submerged beneath the waters of Lake Powell. River mileage is derived from the USGS 1921 Plan and Profile maps. River Mile Zero

3025-414: Was soon to be flooded by the new Glen Canyon Dam. Between 1958 and 1960, four investigative phases, combined with other surveys prior to 1957, discovered 250 archaeological sites within the canyon. The Lower Glen Canyon survey was completed in 1958. Excavations began during the summer of 1958 on 16 sites. A thesis emerged that prehistoric people living permanently on the highlands south of Glen Canyon and on

#281718