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Posts tagged Hoover Dam

Dropping Water Levels in Lake Mead, USA – April 6th, 2012

36.1N 114.4W

April 6th, 2012 Category: Image of the day, Lakes, Rivers

USA - April 3rd, 2012

Two large reservoirs can be observed in this image of western USA: Lake Mead, by the left edge, and Lake Powell, created by the Glen Canyon Dam, by the right edge. Both are important sources of water in this arid region. Lake Mead straddles the Arizona-Nevada border, and Lake Powell is on the Arizona-Utah border. Aqueducts carry water from the system to Las Vegas, Los Angeles, San Diego, and other communities in the Southwest.

There is, however, a 50 percent chance that Lake Mead, which was created by the Hoover Dam and the Colorado River, will go dry by 2021 because of escalating human demand and climate change, according to a study by Tim Barnett and David Pierce of the Scripps Institution of Oceanography of the University of California at San Diego.

By 2017, there is a 50 percent chance that the reservoir could drop so low that Hoover Dam could no longer produce hydroelectric power. Water conservation and mitigation technologies and policies thus need to be implemented now, the study stated.

The disappearance of the manmade lake would create a tidal wave of ill effects for the southwestern U.S. The lake provides water for large cities like Los Angeles and Las Vegas, as well as for several agricultural interests. The power also keeps on the lights in that region of the country.

Arms and Basins of Lake Mead, USA

36.0N 114.1W

March 11th, 2010 Category: Lakes, Rivers

USA - March 5th, 2010

USA - March 5th, 2010

Lake Mead is the largest reservoir in the United States. It is located on the Colorado River about 30 miles (48 km) southeast of Las Vegas, Nevada, in the states of Nevada and Arizona. Formed by water impounded by the Hoover Dam, it extends 112 miles (180 km) behind the dam, holding approximately 28.5 million acre feet (35 km³) of water.

The lake is divided into several bodies. The large body closest to the Hoover Dam is Boulder Basin. The narrow channel, which was once known as Boulder Canyon and is now known as The Narrows, connects Boulder Basin to Virgin Basin to the east.

The Virgin River and Muddy River empty into the Overton Arm, which is connected to the northern part of the Virgin Basin. The next basin to the east is Temple Basin, and following that is Gregg Basin, which is connected to the Temple Basin by the Virgin Canyon.

When the lake levels are high enough, a section of the lake farther upstream from the Gregg Basin is flooded, which includes Grand Wash Bay and the Pearce Ferry Bay and launch ramp.

In addition, there are two tiny basins, the Muddy River Inlet and the Virgin River Basin, that are flooded when the lake is high enough where these two rivers flow into the lake. As of now, however, these basins remain dry.

Jagged mountain ranges surround the lake. There are two mountain ranges within view of the Boulder Basin, the River Mountains, oriented north-west to south-east and the Muddy Mountains, oriented west to north-east. From the Virgin Basin, one can view the majestic Bonelli Peak towards the east.

Lake Mead on the Nevada-Arizona Border, USA – August 14th, 2009

36.0N 114.7W

August 14th, 2009 Category: Climate Change, Image of the day, Lakes

Utah, USA - July 26th, 2009

Utah, USA - July 26th, 2009

The contours of the Nevada and Arizona landscape around Lake Mead and the Colorado River appear quite sharp in this orthorectified image. Filled by water impounded by the Hoover Dam, Lake Mead is the largest reservoir in the USA.

However, the combination of a huge demand for Lake Mead’s water and climate change has resulted in a 100 foot drop in this large lakes’s water level since 2000. Although that may not seem to be a great deal of water loss, it is important to remember that the vast reservoir is wide at the top but narrow at the bottom. This means that the 10% drop in depth actually represents a 50% loss in volume.

This huge loss happened in just nine years – The lake went form 96 percent capacity to roughly 43 percent, as of May 2009. The US Bureau of Reclamation predicts that water levels will drop another 14 feet over the summer.

Last year, researchers at the University of California San Diego concluded that if climate change goes uncurbed and water use is not reduced, Lake Mead could dry up by the year 2021.

Great Salt Lake and Grand Canyon, USA – December 27th, 2008

December 27th, 2008 Category: Image of the day

Great Salt Lake and Grand Canyon, USA - November 17th, 2008

Great Salt Lake and Grand Canyon, USA - November 17th, 2008

Close-up of the Great Salt Lake, Utah

Close-up of the Great Salt Lake, Utah

In this image we have a striking view of part of the states of Utah, Nevada and Arizona, USA.

In the upper left quadrant, we have the Great Salt Lake, dark green in color, with a large region of white salt flats to the West. The light green lake below it is Lake Utah.

East of those two lakes, the snow-covered Uinta Mountains stretch eastward. It is the tallest mountain range in Utah, with almost a dozen peaks exceeding 13,000 feet.

Below the Uintas, running from North to South and less covered by snow, we have the Wasatch Mountains.

Close-up of Lake Mead, Nevada and Arizona

Close-up of Lake Mead, Nevada and Arizona

In the lower left quadrant of the image, we can see Lake Mead, on the Colorado River on the border of Nevada and Arizona.

It is the largest man-made lake and reservoir in the United States, formed by water impounded by Hoover Dam. Lake Mead extends 110 mi (180 km) behind the dam, holding approximately 28.5 million acre feet (35 km³) of water.

East of Lake Mead, where the terrain in the image becomes brownish-red, we can observe the Grand Ganyon winding its way through Arizona.

It is a steep-sided gorge that was carved by the Colorado River. The canyon is 277 miles (446 km) long, ranges in width from 4 to 18 miles (6.4 to 29 km) and attains a depth of over a mile (1.83 km).

Close-up of the Grand Canyon, Arizona

Close-up of the Grand Canyon, Arizona

Following the Colorado River east through the Grand Canyon and north towards the Uintas Mountains, where the terrain becomes even redder, we reach Lake Powell and the famous Monument Valley.

source Wikipedia