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Lake Mead, the largest artificial reservoir in the United States, has fallen to a record-low water level of 1,040.4 feet (317.1 metres) above sea level, highlighting the growing water stress in the American Southwest.

About Lake Mead

• Lake Mead is a major reservoir created by the Hoover Dam on the Colorado River.
• Located along the Arizona–Nevada border, around 40 km east of Las Vegas, it is a crucial source of drinking water, irrigation and hydroelectric power for the southwestern United States.
• The reservoir was formed in the 1930s after the construction of Hoover Dam and was named after Elwood Mead, Commissioner of the U.S. Bureau of Reclamation from 1924 to 1936.
• At full capacity, Lake Mead can hold around 31 million acre-feet (38.3 billion cubic metres) of water. Together with Lake Powell, it forms an important reservoir system for regulating the Colorado River.

Why is Lake Mead Declining?

The decline is driven by a combination of climatic and human factors. Poor Rocky Mountain snowpack reduces snowmelt feeding the Colorado River, while a prolonged multi-decade megadrought has reduced precipitation and increased evaporation because of rising temperatures.

At the same time, water allocations to the seven Colorado River basin states—Arizona, California, Nevada, Colorado, New Mexico, Utah and Wyoming—and Mexico have historically exceeded the river's average natural flow, contributing to chronic overuse.