CVIndependent

Sat02292020

Last updateTue, 18 Sep 2018 1pm

Three years ago, state hydrologists in the Colorado River Basin began to do some modeling to see what the future of Lake Mead—the West’s largest reservoir—might look like. If the dry conditions continued, hydrologists believed, elevations in Lake Mead—which is fed by the Colorado River—could drop much faster than previous models predicted.

For decades, the West’s big reservoirs were like a security blanket, says Anne Castle, the former assistant secretary for water and science at the Interior Department. But the blanket is wearing thin. Under normal conditions, Lake Mead loses 1.2 million acre-feet of water every year to evaporation and deliveries to the Lower Basin states plus Mexico; that all amounts to a 12-foot drop. Previously, extra deliveries of water from Lake Powell offset that deficit, but after 16 years of drought and increased water use in the Upper Basin, those extra deliveries are no longer a safe bet.

“There’s a growing recognition that even these huge reservoirs aren’t sufficient to keep the water supply sustainable anymore,” says Castle.

For the three Lower Basin states—California, Arizona and Nevada—that rely heavily on Lake Mead, the situation is particularly urgent. For the last several years, Mead has hovered around 1,075 feet above sea level, the point at which harsh water-rationing measures kicks in. And if conditions in the reservoir continue to worsen, the Interior Department could even take control of water allocation from Lake Mead.

So with the threat of a federal takeover looming, water policy leaders in the Lower Basin states, along with the Bureau of Reclamation, the reservoir’s operator, began meeting last summer to discuss ways they can jointly boost water levels in Lake Mead. Some of the details are now available and indicate that all three states are now willing to accept additional water cuts from the reservoir on top of the cuts that they previously agreed to make in 2007.

Those measures follow a set of federal guidelines adopted nine years ago to manage water deliveries from Lake Mead, given the likelihood of future shortages. The guidelines established a series of thresholds for the reservoir’s water levels that would trigger increasingly severe cutbacks for the Lower Basin states. At the time they were negotiated, few people anticipated that the drought would last as long as it has, but as Lake Mead inched closer to the critical 1,075 mark, water managers in the Lower Basin realized the existing guidelines were not enough to prevent an eventual shortage.

While the terms of the new agreement between California, Arizona and Nevada are still being negotiated, a few details have emerged. For starters, the Bureau of Reclamation has pledged to cut 100,000 acre-feet annually through efficiency measures such as lining irrigation canals to prevent seepage, or possibly by re-opening the long-shuttered Yuma Desalting Plant.

The three states’ willingness to collectively ration their water use would have been unthinkable just a few decades ago, when states fought each other in court to win as much water from the Colorado River. The cooperation is a nod to how new climate realities are re-shaping old water politics in the West. Take California, for instance. Legally, the state could hold on to every drop until Lake Mead is nearly down to mud, since the 1968 law that authorized the Central Arizona Project’s construction gave California the highest priority water rights to the Colorado River. But at that point, says Castle, they’re just as impacted as everyone else.

Other collaborative agreements to reduce the strain on the Colorado River include a 2014 Memorandum of Understanding between the big water providers in the Lower Basin states, the Bureau of Reclamation and the Central Arizona Project, pledging “best efforts” to conserve 40,000 acre feet in Lake Mead. In 2014, major municipal water providers in Arizona, California, Nevada and Colorado also agreed to fund new water conservation projects through a pilot initiative called the Colorado River System Conservation program.

For the Lower Basin especially, the negotiations are necessary to avoid the potential federal takeover, says Tom Buschatzke, the director of the Arizona Department of Water Resources. Although the secretary of the interior, Sally Jewell, has not voiced any immediate plans to that effect, in the past, she has made public statements on the matter.

For Buschatzke, the threat is clear: “She’ll take action if we don’t collaborate,” he says.

Here are the cuts states could face:

Arizona would lose 512,000 acre-feet of its total 2.8 million acre-feet per year allotment if Lake Mead dips below the 1,075 feet threshold. That’s 192,000 acre-feetmore than the 320,000 acre-feet it had previously agreed to cut under the 2007 guidelines. Further cuts occur if the reservoir continues to drop. In another unprecedented move, Arizona water officials are talking about trying to spread cuts across all sectors of the state’s economy that rely on CAP water for drinking and irrigation—cities, farms, industries, Indian tribes and others—instead of letting only farmers take the brunt of the cuts, as dictated by their junior water rights.

California: Thanks to the 1968 law that authorized CAP’s construction, California’s 4.4 million acre feet allotment is shielded from most of the cuts should a shortage on Lake Mead be declared. But as part of the new negotiations, the state has volunteered to cut its water use from Lake Mead by 200,000 acre feet if the reservoir’s levels fall below 1,045 feet, and up to 350,000 acre-feet if levels sink to 1,030 feet.

Nevada: The state with the smallest allotment of Colorado River water, Nevada would take a much smaller share of the cuts—8,000 acre-feet if Mead drops below 1,045 feet, and 10,000 acre-feet after that—because it has the rights to only 300,000 acre-feet.

According to Buschatzke, the three states anticipate finalizing the agreement by early this fall, at which point negotiators will begin working the new measures into law. Those changes in law will likely not happen before 2017.

For Castle, the discussions are part of a new era in water politics—one that looks increasingly collaborative.

“We haven’t seen states versus state or state versus feds for a long time,” she says. “There’s a recognition that litigation is failure—that we need to come together and make things work.”

Sarah Tory is a correspondent for High Country News, where this story originally appeared.

Published in Environment

When the Hoover Dam was built in 1936, it was the largest concrete structure—and the largest hydropower plant—in the world, a massive plug in the Colorado River, as high as a 60-story building.

For nearly 80 years, the dam has been producing dependable, cheap electricity for millions of people in the Southwest, but as water levels in Lake Mead continue to drop, the future of “the greatest dam in the world” is more precarious than it ever has been, and utilities across the desert—including local power provider Southern California Edison—are taking notice.

Lake Mead, the 112-mile reservoir created by the dam, was recently projected to hit 1,074.73 feet above sea level, the lowest it has been since it was filled in 1937. Thanks to a 16-year drought and serious over-allocation, Lake Mead is now just 37 percent full. Although a “miracle May” of rain means the water level will rise again, the longer term prognosis is more worrisome: If water levels continue their downward trend, the amount of energy generated by the Hoover Dam will fall, leading to higher electricity costs for 29 million people in the desert Southwest.

That's because a shallower reservoir means less water pressure against the turbines, generating less electricity. A recent report by graduate students at the University of California, Santa Barbara, in conjunction with the Western Water Policy Program, examines the economic and physical impacts as Lake Mead’s elevation falls: With each 25-foot drop, total energy costs increase by roughly 100 percent, compared to a full reservoir. The costs paid by contractors for hydropower double at 1,075 feet, triple at 1,050 feet, and quadruple at 1,025 feet. At 895 feet, the turbines won’t run—a level they call “dead-pool.”

Dead pool is not imminent, and in the short term, less generation at Hoover won’t translate into soaring electrical bills, says Frank Wolak, an economics professor at Stanford. That’s because utilities buy “futures” contracts for energy, which guarantee a certain price for a period of time. It’s like buying a plane ticket in advance: The price is significantly less than one bought on the same day as a flight. In the case of Hoover, many of those contracts span up to 10 years and were negotiated before low water levels became a significant concern.

Still, Hoover’s power capacity has dropped nearly 25 percent since 2000, and the 53 hydropower facilities run by the U.S. Bureau of Reclamation across the West are producing 10 percent less power than a few years ago, despite rising demand. So when those futures contracts run out—and continued low water levels appear likely—bottom-barrel prices for hydropower will likely be a thing of the past.

That means that utilities currently relying on Hoover’s power, such as the Overton Power District No. 5, which serves 15,000 people in Nevada on the southern end of Lake Mead, are wary. Overton buys 20 percent of its power from the Hoover Dam, 5 percent from other hydro projects, and 75 percent on the spot market (where energy is traded on day-by-day basis). The utility anticipates having to replace 5 percent of its hydropower with another, more-expensive energy source, says Mendis Cooper, Overton’s general manager. That switch won’t translate into sky-high energy bills, likely just a 1 to 2 percent increase. But if Lake Mead continues to fall, and shortages become routine, his customers could see more dramatic increases in their electricity bills. 

“We’ve been having those discussions,” Cooper says, noting that the major topic is moving to more renewables, like solar, as well as improving efficiency.

Luckily, the West has ambitious renewable goals, says Wolak, which will likely make up more of the region’s energy mix and help mitigate the loss of hydropower in the future.

Still, renewables aren’t a panacea. Wind and solar are far more volatile and require backup power sources, such as gas-fired power plants. And though the prices for renewables have come down in recent years, they’re still no match for cheap, federally subsidized hydropower.

“They solve the resource issue,” Cooper says, “but not the price issue.”

Sarah Tory is an editorial fellow at High Country News, where this story first appeared.

Published in Environment