Brandon Loomis

The Republic | azcentral.com

Negotiated interstate shortage plan kicks in if Lake Mead stays below 1,075 feet

California agrees for the first time to take a smaller share of the Colorado

Officials still don't expect to impose restrictions this year

Arizona water officials this week began a campaign to persuade city water departments, irrigation districts and others to accept newly envisioned cuts to their Colorado River supplies.

They hope the proposed temporary reductions will keep Lake Mead from plunging even further. They hope the proposed temporary reductions keep the level from plunging even further.

The reservoir sunk to an all-time low elevation at 1,074½ feet Wednesday night, only hours after the officials introduced their proposal.

Friday night, the level dropped even more, to 1,074.33 feet.

River managers will impose water restrictions on Arizona if the lake stays that low after summer irrigation demands ease up, but they're not expecting that this year.

The Arizona Department of Water Resources and the Central Arizona Project briefed hundreds of Arizonans on a negotiated interstate drought contingency plan that would voluntarily increase the state's enforceable water cutbacks if the Las Vegas-area reservoir behind Hoover Dam drops in the next few years. Those cutbacks, though, are meant to prop up the giant reservoir's levels and prevent a longer-term, worst-case scenario in which the canal delivering Colorado River water to Phoenix and Tucson could run dry.

Essentially the plan means reducing the state's yearly pumping of Colorado River water by enough to supply Tucson, twice. That's in addition to larger cuts the state already expected to absorb if Lake Mead continues its downward trend in the next year or two.

INTERACTIVE MAP: Tracing the path of the Colorado River

The proposed austerity would likely raise water rates because the canal system would still need to recover its costs but do it with less water to sell.

"Higher prices, for sure," CAP General Manager Ted Cooke said when asked of the plan's consequences. "This is going to be expensive."

The cost that communities pay for CAP water could rise by about 45 percent, though the price hike to a city's consumers would be much less. That's because the big costs already folded into their bills are for water pipes and treatment plants — not the water itself.

Lake Mead drops to lowest level in history

None of it would happen for at least a couple of years, as federal water managers predict only a 10 percent chance that they'll need to impose a water shortage next year. By 2018, though, the U.S. Bureau of Reclamation says the odds that the drought-stricken reservoir will require a shortage are better than even.

Depending on the community and its water sources, it's more likely to add a few dollars to a monthly bill.

But first the Department of Water Resources must sketch out how the various groups such as cities and farmers would split water reductions, and then get legislative approval. Officials will spend the summer seeking consensus before presenting a finished plan in the fall.

While trying to prevent a crisis, state officials stress that they are not currently in one. The Colorado River is becoming less reliable, but it represents less than half — 40 percent — of the state's supply.

Until now the state has had excess river water to store underground for later retrieval.

Conservation efforts helped. Arizona uses roughly the same amount of water it did six decades ago, when its population was a sixth of what it is today, according to the Department of Water Resources.

The state has always had to work to stay ahead of water scarcity, and this plan is designed to prepare the state for the future.

"Water is a legacy issue in Arizona," CAP Board President Lisa Atkins said. "The system has reached that tipping point that we knew would come someday."

Arizona years ago agreed to give up one-fifth of what CAP pumps from the Colorado in any year that Lake Mead's level starts out lower than 1,075 feet above sea level. The new plan would ratchet that loss up to almost one-third of what currently flows through the canal.

But California also would agree to take a smaller cut, whereas it has never been slated to take a shortage from the Colorado before.

If the final plan has Arizona cities sharing in the cutbacks, it wouldn't necessarily mean they have to cut usage immediately. Some, such as Phoenix, might absorb the loss by giving up the excess water they're currently putting into underground storage.

Ultimately the goal is to keep Lake Mead from dropping below 1,025 feet above sea level, at which point the parties worry the U.S. Interior secretary could take unilateral action.

For instance, the secretary could cut CAP's take of the river to zero in order to uphold a treaty with Mexico or to supply Californians who have the oldest water rights.

State officials believe the proposed plan greatly reduces the odds that the reservoir will drop that low — from about a 1-in-4 chance by 2022 with no action to 1 in 10 by then with the reduced usage. Even if the level were to drop into the danger zone, they say, the plan likely would keep it from staying there year after year.

The plan is an insurance policy, said Clint Chandler, assistant director of water planning at the Department of Water Resources — Arizonans pay some now to prevent trouble later.

He and others will spend the summer meeting with water users before the department director, Tom Buschatzke, drafts a plan that would assign water restrictions to each sector. That plan likely would shift previously assigned water priorities, meaning cities might share in the first rounds of cutbacks instead of letting farmers bear all of them.

If it means softening the cities' losses from what would otherwise be deeper losses as Lake Mead drops further, it could be worthwhile, said Warren Tenney, executive director of the Arizona Municipal Water Users Association.

"It shows our (state's) legacy of always looking forward, trying to avoid bigger problems," said Tenney, one of more than 300 who attended the briefing either in Phoenix or at remote viewing centers around the state.

"It will take resourcefulness," said Chandler, the state water planner. "It's a Team Arizona circumstance."

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