Colorado River states reach landmark agreement

Water from the Colorado River keeps 30 million people alive, and it sustains a $1.2 trillion regional economy in cities like Los Angeles, Phoenix, Las Vegas and Denver, and throughout the rural West. In recent years, however, drought and competing urban growth have raised tensions among the seven states that depend on the river. Now, a groundbreaking agreement signals a new level of cooperation between those states, and clears the way for the West’s booming cities to buy water from farms — potentially even from farms in other states — to protect themselves in extreme drought.

For the past year, representatives of California, Arizona, Nevada, Colorado, Utah, Wyoming and New Mexico have been meeting behind closed doors. Officially, they’ve been deciding what to do if a drought gets so bad that there’s not enough water to go around. Unofficially, however, they’ve been trying to get more water to Las Vegas, in an effort to prevent the Southern Nevada Water Authority from blowing apart the entire Colorado River Compact.

The 1922 Compact gave Nevada a paltry 4 percent of the river’s flow, and Patricia Mulroy, the head of the Water Authority, is outspoken about her willingness to try to overturn it in court. "If there is no way that the Compact can accommodate Nevada," she said last fall, "then Nevada has no choice but to consider the Compact broken."

But on Feb. 3, after an intense final round of negotiations, the states announced an agreement that should avert the legal warfare. The proposal, which is still being refined and must be approved by U.S. Interior Secretary Gale Norton, helps all seven states by better coordinating operations at the river’s two main reservoirs, Lake Powell and Lake Mead. But it also contains a package of bail-out programs for Las Vegas, which will hit the limit of its existing water supply in just seven years if it continues growing at its current breakneck pace.

Las Vegas reaches for water

Mulroy won a significant concession that will allow Las Vegas to stretch water from its massive proposed Great Basin groundwater pumping project much further (HCN, 9/19/05: Squeezing Water from a Stone). If that project wins federal and state approval, it will pump between 125,000 and 180,000 acre-feet of groundwater a year (each acre-foot is enough for two homes in Las Vegas). Now, with the six other states’ consent, the Southern Nevada Water Authority can reuse the treated wastewater from the project that will flow into Lake Mead, effectively increasing that supply by 70 percent.

But the groundwater project faces numerous challenges and won’t be finished until 2018 at the earliest. In the meantime, Las Vegas will pay the federal government $80 million to build a new reservoir along the California-Mexico border. The reservoir will catch overflow that farmers in the region currently can’t use; in return for funding the project, Las Vegas can take an equivalent amount of water out of Lake Mead until its groundwater project is in place.

Mulroy has also agreed to abandon a controversial plan to tap the Virgin and Muddy rivers, tributaries of the Colorado (HCN, 9/19/05: ‘Tributary issue' could force a seven-state showdown). Now, her agency will fund a study of ways to "augment" the flow of the Colorado River over the longer term. One of the most promising options is a swap in which Las Vegas would pay for a seawater desalination plant in Mexico that would supply water to Tijuana and Mexicali, in exchange for access to part of Mexico’s share of the Colorado.

The "farm reservoir"

Under the terms of the new agreement, cities in one of the Lower Basin states — Arizona, California and Nevada — could lease water from farmers in another Lower Basin state, marking a quiet but significant shift. Farms use more than 80 percent of the river’s water, and that water is potentially an additional reservoir that cities could use to protect themselves from what Mulroy calls "catastrophic shortage."

Because southern Nevada has very few farms to which Las Vegas can turn, interstate transfers are particularly attractive to the Southern Nevada Water Authority. But such leases, particularly ones that idle farmland to free up water, are controversial. Mulroy has attempted them before, but, she says, "The resistance from the other states is enormous."

During the past year’s negotiations, however, Colorado, Wyoming, Utah and New Mexico have tried to safeguard their shares of the river by encouraging the more heavily developed Lower Basin to find water from farms in central Arizona and in California’s Imperial Valley.

"There is plenty of room within the Lower Basin for leasing, marketing, transfers (or) exchanges, while still protecting what we have in the Upper Basin," Jim Lochhead, one of Colorado’s negotiators, said last August.

There is no shortage of water to work with in an emergency: Jennifer Pitt, with the nonprofit group Environmental Defense, estimates that there is a pool of some 2.3 million acre-feet of water, enough for nearly 5 million homes, that cities could lease from farmers in the Lower Basin for less than $100 an acre-foot.

Realistically, cities would only lease far smaller amounts to cover their shortages in a drought. And officially, at least, water managers are downplaying the interstate leasing option. "We’re not there yet," says Bill Hasencamp with the Metropolitan Water District of Southern California, which supplies water to Los Angeles and San Diego. But other sources close to the negotiations say that under the new proposal, which the states hope to finalize this fall, interstate leases are clearly allowable.

Just how far the states will take them remains to be seen. Putting together individual deals, which will most likely be one-year arrangements that pay farmers to fallow their land and transfer water, will still require a tremendous amount of diplomacy to prove that farms won’t be dried up permanently.

While "there’s a pretty tremendous buffer in all that agricultural water use," says Pitt, individual states will always be hesitant to lease it outside their borders for one very big reason: "They see it as their reserve for future growth," she says, and they’re concerned that "once you let it out of the state, you won’t get it back."

The author is an HCN associate editor.

This article was made possible with support from the William C. Kenney Watershed Protection Foundation and the Jay Kenney Foundation.

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