Lake Powell 鲍威尔湖

鲍威尔湖（Lake Powell）是为纪念美国第一个漂流此河并建议开发水利的先驱而命名的。
其面积是米德湖的两倍多，有各种红色砂岩、石拱、峡谷和万面碧波，其风景远胜米德湖，已成为美国西南部的主要国家度假区。

鲍威尔湖是蜿蜒在美国亚利桑那州和犹他州之间的天然水库，但同时也是西部水危机的最典型代表。至2015年4月，鲍威尔湖的储水量只有其正常状态的42%。

1956年，建筑格伦峡谷水坝时就已经着手建造鲍威尔湖了，但直到1980年将科罗拉多州、圣胡安州的河流以及埃斯卡兰特河流的水引入之后它才真正意义上完工。

鲍威尔湖的修葺史几乎就是这个地区的近代史，它能够唤起西部人和当地土著对于十九世纪欧洲殖民者对这里无情的掠夺的记忆。在这片土地成为广阔平静的湖面之前，它是属于纳瓦霍人的，他们被迫用这片肥沃的土地交换犹他州南部的相同大小的土地，但是那里的土地几乎不能用来耕种。

现在在美国已经有超过5百万土著人，而且他们的人数还在迅速增长。这些土著人很多都致力于收回他们祖先的土地，鲍威尔湖也许会再度成为纳瓦霍人的领地。
早在1972年鲍威尔湖就建立了水上休闲娱乐中心，每年的来自世界各地的游客有三百万之多。

鲍威尔湖以探险者John Wesley Powell将军命名，是美国第二大人工湖。位于犹他州和亚利桑那州交界处的鲍威尔湖是世界上最大的人工湖之一。经测量，这个湖占地面积6.5万公顷，170米深，300公里长，同时拥有着3500千米长的海岸线。
鲍威尔湖是圣胡安河西部的一个分支。圣胡安河发源于科罗拉多州南部的一河流，流程约579公里（360英里），流经新墨西哥西北和犹他州东南后注入科罗拉多河。

Lake Powell is a reservoir on the Colorado River, straddling the border between Utah and Arizona (most of it, along with Rainbow Bridge, is in Utah). It is a major vacation spot that around 2 million people visit every year. It is the second largest man-made reservoir by maximum water capacity in the United States behind Lake Mead, storing 24,322,000 acre feet (3.0001×1010 m3) of water when full. However, due to high water withdrawals for human and agricultural consumption, and because of subsequent droughts in the area, Lake Powell is currently larger than Mead in terms of volume of water currently held, depth and surface area. Lake Powell was created by the flooding of Glen Canyon by the Glen Canyon Dam, which also led to the creation of Glen Canyon National Recreation Area, a popular summer destination. The reservoir is named for explorer John Wesley Powell, a one-armed American Civil War veteran who explored the river via three wooden boats in 1869.

In 1972, Glen Canyon National Recreation Area was established. It is public land managed by the National Park Service, and available to the public for recreational purposes. It lies in parts of Garfield, Kane, and San Juan counties in southern Utah, and Coconino County in northern Arizona. The northern limits of the lake extend at least as far as the Hite Crossing Bridge. A map centered at the confluence of the Escalante River  WikiMiniAtlas37°17′22″N 110°52′20″W with the Colorado River gives a good view of the extent of the lake.

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 km3) to the Lower Basin states (Arizona, Nevada, and California).

Glen Canyon was carved by differential erosion from the Colorado River over an estimated 5 million years. The Colorado Plateau, through which 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 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, the result of more compressed sand dunes. Many of the arches, including Rainbow Bridge, lie at this transition point. This period also includes light yellow Entrada Formations, 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 Straight Cliffs Sandstone and conglomerate shales that make up 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.