States expected to reduce water taken from Lake Mead

• Lake Mead is at historically low levels
• Water agencies asked to reduce amount of water taken from Lake Mead.
• Drought is threatening one of the main resevoirs of Colorado River water.

Arizona and various water agencies in Nevada and California are expected to approve an agreement this month that would reduce the amount of water taken from Lake Mead.

The measure is considered a significant step toward protecting one of the main reservoirs of Colorado River water.

The lake is at historically low levels because of a 14-year drought.

Water levels have dropped to 1,085 feet above sea level, the lowest since the lake was first filled more than 75 years ago. That's only 10 feet above the level that would trigger cuts in water deliveries by the federal government to Arizona and Nevada. Farms would be affected before cities.

Officials say if nothing is done, the cuts could happen as early as 2016 if precipitation levels fall below normal.

"All of this is an effort to keep the elevation of Lake Mead above the level at which a shortage would be declared," said David Modeer, general manager of the Central Arizona Project.

CAP officials said in a statement that "if Lake Mead's elevation continues to decline at its current pace, the water supply for more than 40 million people and 4 million acres of farmland ... face increased jeopardy."

The CAP manages canals that divert water from the Colorado and supply Pima, Pinal and Maricopa counties.

Modeer said a tremendous amount of planning has gone into trying to stem the effects of a water shortage in Arizona. Lots of water is stored underground. But if the drought continues and water levels continue to decline, "there are conditions in nature that are going to obviate all the planning we've done if we don't take extraordinary action," he said.

The agreement has been approved by the Arizona Department of Water Resources and the CAP. It must still be approved by other participants in Nevada and California. Modeer said he anticipates all the parties will sign off this month.

The Associated Press contributed to this article.