Ian James

TDS

Lake Mead, the largest reservoir in the country, has dropped to its lowest level since it was filled in the 1930s, a decline that reflects 14 years of drought and a growing imbalance between the Colorado River's flows and the demands of cities and farms across the Southwest.

The white band left on the lake's rocky banks by minerals in the receding water now stretches more than 130 feet below a high-water mark last reached in 2000. And as the reservoir continues to ebb, water managers from across the region have begun negotiating steps they could take jointly to avert a serious shortage that would trigger cutbacks in water deliveries to Arizona, Nevada and Mexico.

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"It's time for us to wake up. If this drought continues, we're going to be in a terrible situation within the next 12-24 months," said Jay Famiglietti, senior water scientist at NASA Jet Propulsion Laboratory. His research, which uses satellites to track changes in water supplies, has confirmed that the Colorado River Basin has lost vast amounts of groundwater during the past decade.

The fact that Lake Mead is now 39 percent full shows how dire the water situation has become, Famiglietti said. "I think it says that this region is in trouble. I think it says that we need to really rethink our water use in this region, our demand in this region because it is far outstripping the supply."

Last week, the level of Lake Mead slipped below the previous record set in 2010 of 1,081.85 feet above sea level, as measured by the Bureau of Reclamation. As of Sunday, the water level stood at about 1,081.7 feet, and the reservoir is expected to continue declining for several months.

Lake Mead is then projected to rise somewhat by the end of the year, boosted by flows released from Lake Powell after a year with normal snowpack. But that's just one year in a larger drought, and the Bureau of Reclamation has estimated that by 2017, there will be a 50-50 chance of lower water levels prompting the declaration of a shortage. Starting in 2018, the estimated likelihood of reaching that threshold — and cutbacks in water deliveries — rises to 60 percent.

About 25 million people and vast areas of farmland depend on the reservoir, which was filled after the completion of Hoover Dam in 1936.

The Colorado River would naturally flow through its delta to the Sea of Cortez. But so much water is taken from the river that it seldom reaches the sea, and federal officials say water use has begun to surpass the available supply, drawing down the river's reservoirs.

Using tree rings, scientists have been able to assess the severity of droughts in the West going back centuries. They have determined that the dry spell since 2000 in the Colorado River Basin is one of the most severe in more than 1,200 years.

Scientists predict climate change will worsen droughts in the region. They also say hotter average temperatures already have begun to exacerbate strains on water supplies by diminishing mountain snowpack and triggering earlier melting of snow in the spring.

The shift in climate in recent years is bringing uncertainty and volatility, and coping will require innovative solutions as well as all parties working together to address water issues in new ways, said Kimery Wiltshire, executive director of Carpe Diem West, a nonprofit organization that focuses on addressing impacts of climate change on water supplies. She said potential remedies in many cases are failing to take hold due to entrenched interests, antiquated laws, and "a myopic focus on next year's supply" among water managers.

"We know about solutions that must be scaled up across our arid lands — water recycling, water banking, water pricing," Wiltshire said. "But politics is the problem. What is lacking is the political will, and the drive toward innovation, that will allow us to make the transition to a water-sustainable society."

Greater incentives must be provided to encourage water conservation by individuals as well as by water districts and utilities, said Doug Kenney, director of the Western Water Policy Program at the University of Colorado Law School.

"It's all doable, but there needs to be some leadership, and it's hard to find that leadership when the current situation favors some water users over others, and any tinkering of the rules is going to be viewed as threatening to someone," Kenney said.

State officials and managers of water districts from Nevada, Arizona and California met along with federal water managers for two and a half days of negotiations last week at a hotel in Manhattan Beach, aiming to come up with steps that would stem the declines in Lake Mead and prevent worsening shortages.

Robert Cheng, assistant manager of the Coachella Valley Water District, attended the meetings and said the negotiations focused on finding "some voluntary measures to leave water in Lake Mead to protect all of our interests."

No agreements have yet been reached, Cheng said. "Everything's sort of on the table right now."

California has the most senior rights to water from the Colorado River among the states represented at the negotiations. Officials of local water districts say that for California to face cutbacks, the level of Lake Mead would have to drop about 80 feet more, which isn't anticipated anytime soon.

The Coachella Valley Water District is due to receive 352,000 acre-feet from the Colorado River this year. That water, enough to fill up nearly 175,000 Olympic-size swimming pools, flows through the Coachella branch of the All-American Canal to farms and golf courses, as well as to ponds that are used to replenish the underground aquifer.

The water district has been trying to use the imported water to combat long-term declines in groundwater levels, and it has plans to connect more of the area's 124 golf courses to pipes carrying a blend of recycled wastewater and Colorado River water.

John Powell, president of the CVWD board, pointed out that the water district negotiated to win rights to additional amounts of Colorado River water under a 2003 deal known as the Quantification Settlement Agreement. So while the agency says it is taking steps to encourage conservation of local groundwater, the situation is different when it comes to water from the Colorado River.

"We're working to get that water to more people in the Coachella Valley because we have it, we have it available. So we're trying to use more of it," Powell said.

"Any reduction in our use of Colorado River water is going to end up going to somebody else," Powell said. "To the extent we need it here, we're not going to give it up to someone else."

Powell said there may be other ways to generate water, such as recycling and reusing water that runs off agricultural lands, and that the district is cooperating with other agencies to look for solutions.

The modern laws that govern allocations of water from the Colorado River were drawn up during much wetter times, starting with the 1922 Colorado River Compact. And while those laws have since evolved, the water entitlements crafted during the 20th century no longer match the river's flows. In recent years, water scientists have increasingly warned that the river is fundamentally over-allocated.

"It's very likely that the allocations need to be rethought," Famiglietti said. "Is it going to be a congressional thing? Is it going to be the western governors that get together or some combination? It probably has to be a top-down thing."

Some governors and members of Congress clearly recognize a need to rethink water across the Colorado River Basin, Famiglietti said. "They also recognize that it is a total quagmire, and that's the issue: Could it actually get done politically? And I think there would have to be a tremendous amount of political will."

Ian James can be reached by email at ian.james@desertsun.com and on Twitter at @TDSIanJames.