Lake Mead, the largest reservoir in the United States, has plummeted to its lowest water level since it was filled about 90 years ago, according to federal data. The water level hit 1,040.4 feet (317.1 meters) above sea level on Friday, as reported by the US Bureau of Reclamation.
Held back by the Hoover Dam and straddling the Arizona-Nevada border outside Las Vegas, Lake Mead is a critical storage system on the Colorado River. The river supplies roughly 40 million people across seven US states, tribal nations and Mexico, and irrigates millions of acres of farmland. A continued drop in its level would imperil water supplies for millions and cut electricity from the Hoover Dam.
Lake Mead's water level on Friday, its lowest since being filled about 90 years ago.
Lake Powell, the second-largest reservoir in the US and the other major storage on the Colorado River, is also at historic low levels. Both reservoirs are the lowest they have been in nearly seven decades. Levels at Lake Powell have dropped so much that it has become difficult to reach the water, and boat ramps have had to move, shut down or be built anew.
The Colorado River basin is facing pressure from overuse, prolonged drought, extreme heat, and a lack of snowmelt. The past winter saw the worst snowpack on record for the basin. Drought and dry conditions have stretched along the length of the river and are particularly intense at its source in the Rocky Mountains. Years of overuse combined with drought and rising temperatures have been depleting both reservoirs.
US federal officials on Thursday said they will not release cool Lake Powell water from Glen Canyon Dam in northern Arizona to protect a threatened native fish, the humpback chub, whose habitat is between the reservoirs. Separately, officials recently announced a short-term proposal to address the water crisis after the seven states that rely on the Colorado River – California, Colorado, Arizona, Nevada, New Mexico, Wyoming and Utah – failed to reach a long-term agreement. The federal proposal called for the Lower Basin states of Arizona, California and Nevada to take less water.
The US Bureau of Reclamation said its plan was flexible, allowing deeper cuts in drier times and more time for states to agree on managing scarce resources. The US government is expected to release a 'record of decision' in the coming weeks offering more details on the plan.
It's extremely significant and extremely concerned.
JB Hamby, who chairs the Colorado River board of California and serves on the Imperial Irrigation District board, said that three-quarters of the population of the Colorado River basin, some 30 million people, are directly impacted by risks to Lake Mead. He said it is vital for states that use Colorado River water to reduce water use. The Imperial Irrigation District is the largest user of the Colorado River's water.
Severe drought in 2022 on Lake Mead exposed human remains and forced water officials in Las Vegas to pump water from deeper within the reservoir to supply millions of people. Of the 54 western reservoirs tracked by the US Bureau of Reclamation, nine recently recorded their lowest levels in the last three decades. US federal officials do not believe the record low at Lake Mead will stay; modeling done in July forecasts the reservoir to continue dropping through much of the rest of the year.
