Lake Mead falls to lowest level on record

Lake Mead, the largest reservoir in the United States by storage capacity, has fallen to the lowest level in its recorded history, extending a decline driven by a drought across the western U.S. that has run for more than a decade. The reservoir, formed by Hoover Dam on the Colorado River, supplies water to Nevada, Arizona, California and parts of Mexico, and its elevation also determines hydropower output at the dam. Declining levels trigger graduated shortage conditions under Colorado River management rules, reducing allocations to lower-basin states. Continued declines put pressure on agricultural users, municipal suppliers and utilities that rely on Colorado River hydroelectric generation, and factor into negotiations over post-2026 operating guidelines for the river system.