|In late May 2016, Lake Mead – which helps supply water for 25 million people in Nevada, Arizona, and California — declined to its lowest level since the reservoir was filled in the 1930s. California recently eased its sweeping restrictions on water use, signaling that even though much of the state continues to face extraordinary drought, a moderately wet winter has blunted officials’ sense of urgency over water shortages. Overlooked is the state’s enormous reliance on the Colorado River for its water supplies – it is approaching its worst point of crisis in a generation.|
The Colorado River provides much of the drinking water for some 19 million of California’s 39 million residents. In San Diego County, water from the river comprises 64 percent of total supplies. On May 18 – the same day the control board lifted its restrictions – Lake Mead reached its lowest point since 1937.
|The U.S. Bureau of Reclamation, which manages Lake Mead and distributes Colorado River waters, predicts the reservoir – now 37 percent full – will reach a new low in 2017, part of a steady decline that began more than a decade ago as water users continued to draw far more out of the Colorado River each year than it provides. California is the single largest draw on this resource – using nearly one-third of the entire Colorado River’s flow.|
More than 43 percent of California remains in “extreme drought.” California pumped deeply into its groundwater reserves over the past half-decade, depleting supplies. Replenishment will take many wet years – if not centuries. The Colorado Basin has endured roughly 16 years of drought while population continue to grow in the sun-drenched region.