States make water deal

Wednesday, Oct. 13, 2004 | 10:43 a.m.

Water agencies from Southern Nevada and Southern California have brokered a deal to store the rights for up to 30,000 acre-feet of water annually in the Golden State as a reserve against future Las Vegas needs.

The Metropolitan Water District of Southern California approved the deal Tuesday, and the Southern Nevada Water Authority is expected to give the go-ahead for the storage agreement at its regular board meeting Oct. 21. The water authority, the wholesaler supplying almost all of Southern Nevada's consumers with water from Lake Mead, already "banks" water here and in Arizona that the agency does not use from its 300,000-acre-foot basic apportionment from the lake.

An acre-foot is about 326,000 gallons, or about enough water for 1.5 typical families to use in one year.

Under the plan, the Metropolitan Water District would take up to 30,000 acre-feet from Lake Mead in lieu of water Southern Nevada could have taken. Southern California will bank a similar amount of water from its in-state surface and ground water resources -- resources that are of lower quality than the Lake Mead water.

When Southern Nevada needs the water, Southern California will turn to its banked sources and the water authority will take an equivalent amount more from California's share of Lake Mead, up to 30,000 acre-feet annually.

The water authority already banks water locally and is finalizing a deal with Arizona to bank up to 1.2 million acre-feet. While the deal with Southern California is smaller, it has some important advantages, Mulroy said.

Chief among those is that the arrangement will essentially cost nothing. It costs the water authority $280 an acre-foot to bank the water in Clark County, and $143 an acre foot in Arizona, Mulroy said.

While three years ago Southern Nevada was taking more than 300,000 acre-feet from the lake, conservation programs are credited with cutting the water consumed from the lake to 270,000 acre-feet or less. The unused portion can be banked against future needs.

The deal, because it does not involve the physical transfer of water from Southern Nevada, also allows the treatment plant drawing water for Las Vegas from Lake Mead to ratchet down its operations, providing critically important opportunities for maintenance on those plants, she said.

"We need as much ability to bring the treatment plant down as possible," she said. "To run that plant at 100 percent causes us all types of problems."

Mulroy and Dennis Underwood, Metropolitan Water District vice president, said the coordinated banking effort that now includes all three lower basin states of the Colorado River, Nevada, California and Arizona, will assist the region in responding to a crippling drought that now is in its fifth year and is threatening the basic apportionments given to all three states.

Southern California benefits because the relatively clean water from Lake Mead can be blended with lesser quality water, Underwood said. The swap would be particularly important until new treatment facilities for Southern California come on line in 2008 or 2009, he added.

When other potential positive in the deal is not what it does now, but what it suggests can be accomplished in the future by the lower basin states, Underwood and Mulroy agreed.

"This means we're making more effective use of available resources, whether we're reacting to the drought or long term needs," Underwood said. "We're getting better utilization out of each others systems. A lot of this is to deal with this period of drought and beyond.

"There may be other opportunities that you can build on," he said. "It is a building block, or a door opening, for further work."

Mulroy said, "If the drought worsens and we go to the shortage conditions, it's going to be critically important that the three lower basin states work together to meet real demand, and this is a first step in that direction."