The drainage of the Colorado River Basin provides life-preserving water for 33 million residents in seven southwestern US States and two Mexican States in this arid desert region, and electricity to areas in surrounding states.
Glen Canyon Dam and Hoover Dam, creating Lake Powell and Lake Mead, the two largest reservoirs in the US, provide flood control and a steady water supply throughout the Basin.
Cycling banner photos include Lake Powell at the dam, the San Juan Canyon arm of Lake Powell, a large houseboat in the Escalante Canyon Arm of Lake Powell, Lake Mead at the dam, the Desert Princess paddlewheeler amid huge
bathtub rings in Black Canyon near Hoover Dam, and silt in the dry eastern end of Lake Mead as the Colorado exits Grand Canyon.
Since 1999 the southwest has been in a severe drought. Between 1999 and 2005, Lake Powell dropped 145 feet (44+ m) to 33% of capacity. July 1, 2016, Lake Mead set an all-time low, down 148 feet (45 m). This is a combined loss of nearly 11 trillion gallons of water from both lakes. The Lake Powell NASA satellite image overlays dramatically illustrate the progress of the drought.
This year (the water year begins on October 1, 2016 and ends on September 30, 2017) is a very interesting year in that we are in a weak La Niña, which should provide limited precipitation, yet precipitation and snowpack are considerably above average - more than last year's El Niño. The Spring has been wet enough that Southern California has been declared out of drought. The Upper Colorado Basin snowpack has been above average with forecasts of Lake Powell rising from 30 to 50 feet (9-15 meters), which could signal an end to the drought, although long range forecasts are not good.
Menu entries Lake Powell and Lake Mead open galleries, pages with data, graphs, NASA image overlays, and auto-shows; beautiful scenery of the lakes in drought, albeit with
Basin Drainage has a map of the drainage of the Colorado River Basin, with maps of the drainage basins of the three largest tributaries of the Colorado - Green River, San Juan River, and Gila River.
Drought Defined discusses the probem of defining a drought, ultimately deferring to the National Drought Mitigation Center at the Unversity of Nebraska/Lincoln for our definition.
Drought Updates presents periodic updates with data and graphs of the lakes' elevations.
We may jokingly refer to water-bleached bathtub rings, which is incorrect - the deposit of calcium carbonate and other hard minerals on the darker-colored surface of the sandstone is what causes the water-bleached effect which is observable when the water levels are down - dramatically visible during drought.
The Photo Gallery provides a preview of all of the photos and banners of the lakes.