Western States Face First Colorado River Water Cuts As Megadrought Drains Reservoirs

Farmers in Arizona and Nevada, along with two Mexican states, will face cutbacks next year in a grim sign of what’s to come as the climate warms.

Arizona, Nevada and two Mexican states that rely on the Colorado River for drinking water and irrigation will face cuts to their supply next year as a prolonged megadrought parches the American West, leaves reservoirs depleted and casts doubt over the future of vital freshwater reserves as climate change worsens. On Monday, the federal Bureau of Reclamation declared a water shortage at Lake Mead as water levels fell below the 1,075-foot threshold that triggers mandatory reductions in the amount of water the nation’s largest reservoir dispenses to millions in the lower Colorado River Basin.  The cutbacks mark the first time in Lake Mead’s 86-year history that demand for water has eclipsed what federal authorities can safely supply, even in a system where reservoirs store four times more water than what flows annually down the river. The tier-one shortage — the worst designation, based on the lake’s record-low water levels — paints a troubling picture of the hardships to come as the Southwest’s growing population competes for dwindling resources while temperatures rise and precipitation falls due to soaring fossil fuel emissions. The region’s stored water capacity dropped to 40% last month, down from 49% a year earlier.