PHOENIX -- The nation's largest reservoir is approaching an all-time low level mark.
Lake Mead near Las Vegas is expected to hit the mark next week but it would also be seven feet above the level that would trigger a water shortage declaration in Arizona and Nevada.
That could happen in the spring. The Bureau of Reclamation said the lake is down to 1,082 feet -- its lowest mark is a foot less; trigger point for the shortage declaration is 1,075 feet.
Bob Barrett, a spokesman for the Central Arizona Project, said if it reaches that point it won't impact Arizona cities but it could affect some of the state's farmers.
"The first thing you would do is you would stop agriculture deliveries," Barrett said. "You can stop growing cotton but you can't stop growing people. agriculture would have to go back to groundwater."
Even under the worst conditions at the lake, Barrett said Arizona cities wouldn't be impacted for 10-15 years.
"We would start extracting the water we've been storing underground, put it into the canals and make our deliveries," he said.
Unlike Las Vegas which is totally reliant on Lake Mead, the Valley also has the SRP system, which includes Roosevelt Lake, to carry it through the dry times.