America's Largest Reservoir is Drying Up

from GOOD Magazine:

Lake Mead stores water from the Colorado River. When full, it holds 9.3 trillion gallons, an amount equal to the water that flows through the Colorado River in two years. The water from Lake Mead is used for many things. It irrigates a million acres of crops in the United States and Mexico, and supplies water to tens of millions of people. Its mighty Hoover Dam generates enough electricity to power a half-million homes. Additionally, the power from Hoover Dam is used to carry water up and across the Sierra Nevada Mountains on its way to Southern California.

In 2000, the water level at Lake Mead was 1,214 feet, close to its all-time high. It’s been dropping ever since. When Lake Mead was built during the 1920s and 1930s, the western United States was enjoying one of the wettest periods of the past 1,200 years. Even today, our so-called drought is still wetter than the average precipitation for the area averaged over centuries. In other words, for the last 75 years, we’ve been partying like it’s 1929. Farmers grow rice by flooding arid farmland with water from Lake Mead; residents of desert communities maintain front lawns of green grass; golfers demand courses in areas where the temperature exceeds 100 degrees Fahrenheit during the summer.

The combination of a changing climate and a strong demand for the lake’s remaining water has resulted in 100 foot drop since 2000. While that’s just 10 percent under the lake’s high water mark in 1983, Lake Mead is like a martini glass—wide at the top and narrow at the bottom. That 10 percent dip represents a loss of half Lake Mead’s water supply in nine years, from 96 percent capacity to 43 percent.