Lake Mead sinks to record low, risking water shortage

Lake Mead sunk to a record low Tuesday night, falling below the point that would trigger a water-supply shortage if the reservoir doesn't recover soon.

Water managers expect the lake's level to rebound enough to ward off a 2016 shortage thanks to a wetter-than-expected spring. But in the long run, as a U.S. Bureau of Reclamation spokeswoman said, "We still need a lot more water."

The reservoir stores water for parts of Arizona, Southern California, southern Nevada and northern Mexico — all of which have endured a 15-year drought that continues.

The U.S. Bureau of Reclamation will announce a 2016 shortage in August if it projects Lake Mead will hit 1,075 feet at the beginning of next year. Assessments are updated in the middle of every month. This month's report forecasts an improved outlook.

The bureau reported Lake Mead's elevation at 1,074.98 Tuesday night. But the elevation climbed slightly above 1,075 since 2 a.m. MST. Elevation measures are updated every hour.

But Tuesday's record low signals that Colorado River water users consume more than the river provides, said water-policy manager Drew Beckwith of the Western Resource Advocates, a nonprofit environmental law and policy organization.

"This is the check-engine light," Beckwith said. "It really does (make critical) the fact that we have to start changing."

For Las Vegas, the record reinforces the need for a nearly $1.5 billion project to tap deeper into Lake Mead. The Southern Nevada Water Authority soon will complete a 3-mile tunnel that will suck water from an 860-foot elevation level. The plan also includes a pumping station.

The water authority's current "straws" glean water from 1,050 feet and 1,000 feet. Lake Mead hovers around 1,075 feet Wednesday — leaving the first straw just 25 feet away from pulling in air.

Leaders launched the third intake project about 10 years ago, seeking to reach better-quality water at deeper depths. Water closer to the surface is warmer and requires more treatment to bring it to drinking quality, said Bronson Mack, a spokesman for the water authority.

Drought or no drought, the Colorado River is over allocated, Beckwith said. Lower-basin states take more than the river system can sustain.

The upper basin — Colorado, New Mexico, Utah and Wyoming — hasn't used its full allocation for years, which has kept the problem at bay because the excess is sent to Lake Mead. But that setup won't last.

The drought just has hastened that reality, he said.

Western states are working together to start chipping away at the problem.

Major river users agreed last year to leave hundreds of thousands of acre-feet of water in Lake Mead by 2017 that they otherwise would take. The Central Arizona Project's share is 345,000 acre-feet — or the equivalent of more than 170,000 Olympic-sized swimming pools.

Arizona's water-saving strategies include offering incentives for farmers in Yuma to leave some citrus fields fallow and for farmers in central Arizona to cut back on their water consumption.

Phoenix also is tapping into banked water behind the Roosevelt Dam on the Salt River to offset some of its usual consumption directly from the Colorado River. The Salt River flows into the Gila River, which flows into the Colorado at Yuma.

Central Arizona Project officials have said the measure is just the beginning in a slate of solutions that river users will need to take to address long-term drought possibilities.

Arizona has banked water and enacted regulations to protect residents in major metro areas from draconian cuts if a 2016 or 2017 shortage is declared, but agriculture would take a 50% cut from the Central Arizona Project, which brings Colorado River water to the state.

At stake is not solely the Southwest's water supply, but the health of ecosystems surrounding the river and economies that depend on the Colorado River. The river attracts 5.36 million adults a year for recreation, supports a quarter million jobs and generates $26 billion in economic impact, according to a 2012 survey for Protect the Flows, an organization that seeks to protect the river.

Many municipalities in desert cities already have made major cutbacks: Las Vegas residents use 30% less water per capita than they did 10 years ago; Phoenix residents have cut back by 27% in 20 years.

In the Phoenix area, several cities have offered rebate programs for lawn removals and more efficient appliances for years.

"We need to grow in a way that recognizes that we have a limited water supply. That means that all of the new homes that are built should not be importing landscaping preferences from Kentucky or the Midwest," Beckwith said.