August 20, 2016--“Climate change is water change” — why the Colorado River system is headed for trouble (Washington Post)

There’s good news and bad news for the drought-stricken Colorado River system, according to projections just released in a new federal report from the Bureau of Reclamation, manager of dams, powerplants and canals. The report predicts that Lake Mead — the river system’s largest reservoir, supplying water to millions of people in Nevada, Arizona, California and Mexico — will narrowly escape a shortage declaration next year. But a shortage is looking imminent in 2018, and water experts are growing ever more worried about the river system’s future. The Colorado River basin has been plagued with drought for 15 years now, and the effects are starting to show. Earlier this spring, Lake Mead — which feeds 90 percent of the water supply in Las Vegas, alone — dropped to its lowest levels since the Hoover Dam was completed in 1936. In fact, the last time the lake was at full capacity, with water levels 1,225 feet above sea level, was in 1983. Since then, and particularly since the year 2000, its surface levels have been steadily dropping, leaving behind a striking white “bathtub ring” around the shoreline showing how the water levels have decreased over the years. Currently, demand on Lake Mead has been removing more water than is being replenished, resulting in a deficit of about 1.2 million acre-feet, or about 400 billion gallons, each year.

According to federal guidelines, a shortage is to be declared at the start of any given year if Lake Mead’s water levels have sunk below 1,075 feet above sea level. The new federal projections, spanning the next 24 months, suggest that the elevation will be hovering just below 1,079 feet at the end of this December. By the end of December 2017, however, the report predicts that water levels will have sunk to about 1,074 feet. If this occurs, the federal government will declare a shortage and affected states will be obligated to reduce their water consumption. Avoiding a shortage in 2017 can be viewed as a temporary victory, said Jennifer Pitt, the National Audubon Society’s Colorado River project director. “Were it not for some extraordinary efforts by lower basin water users in California, in Arizona, in Nevada and in Mexico to reduce their use of water already, we would in fact have seen a shortage in the lower basin,” she said. To view the full article visit the Washington Post.