New Hope for the Delta

During the worst drought in more than a century, the Colorado River may flow to the sea once more.

  • Mudflats in the Colorado River Delta, near the Sea of Cortez.

    Robert Campbell
  • Francisco Zamora, Colorado River Delta manager for the Sonoran Institute, yanks an errant salt cedar from the bank of a restored area in the Colorado River Delta.

    Erika Nortemann/The Nature Conservancy
  • At a restoration site near Mexicali, local workers plant native trees and set up irrigation systems to help restore the Delta.

    Erika Nortemann/The Nature Conservancy
  • Guadalupe Fonseca inside a nursery growing cottonwood seedlings in Carranza.

    Erika Nortemann/The Nature Conservancy
  • The Ciénega de Santa Clara, formed when a canal (the straight line, top center) was dug to keep polluted wastewater from the Welton Mohawk Irrigation District in Arizona from flowing into the Colorado River. Now, it's the largest wetland in the Colorado River Delta.

    Ronald de Hommel
  • Alejandra Fonseca of Pronatura experiments to see how much water a square meter of riverbed can absorb, which will help determine how much water is needed to sustain small pockets of wetlands in the Colorado River Delta.

    Ronald de Hommel
  • A salt cedar-choked area of the Colorado River Delta before it was restored.

    The Sonoran Institute
  • The same area of the Colorado River Delta after it was restored and cleared salt cedars.

    Erika Nortemann/The Nature Conservancy
 

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Not surprisingly, as the drought deepened – and the system on the U.S. side of the border got tighter and tighter – less and less spring floodwater reached the Delta. "We were losing trees, and we were losing good habitat," says Zamora. "So we decided that we had to do something."

Beginning in 2002, he and Osvel Hinojosa, a 38-year-old, pony-tailed, improbably upbeat ecologist from the Mexican environmental group Pronatura, cobbled together money for a series of small-scale restoration projects. The pair became increasingly well-versed in the nuances of grant-writing and heavy equipment contracting. They rented backhoes to rip out tamarisk; leveled land with laser-guided mechanized graders; installed irrigation systems; and tended cottonwood, willow and mesquite seedlings by hand in a nursery in Carranza, before driving them out to the river, where local crews carefully planted them.

Zamora and Hinojosa envisioned a network of demonstration projects that would not only provide a functioning ecological corridor within the Delta, but also help people understand what an even more ambitious restoration effort might look like. The sites were small, says Zamora, "but once people saw them, they wanted to see more."

Replanting native forest was just part of the challenge. The bigger one was reintroducing the force that energized the Delta's natural dynamics: Water.

And so, even as the water agencies labored to ensure that no "fugitive" water escaped across the border, Hinojosa's boss, Pronatura director Martín Gutiérrez, successfully lobbied to change Mexican law so that nonprofit environmental organizations could purchase water for environmental restoration. In 2008, Pronatura, the Sonoran Institute and the Environmental Defense Fund formed the Colorado River Delta Water Trust, which has subsequently purchased some 3,200 acre-feet of water from local farmers to irrigate the trees in a web of restoration sites that now exceeds 800 acres. The thick cottonwood and willow forests began to spring to life with birds, including long-vanished species like the yellow-billed cuckoo and yellow-breasted chat.

But truly restarting the ecological heart of the Delta was going to take another tremendous pulse of spring floodwater, like the ones that had come charging downriver during the '80s. And to make that happen, the environmental groups had to find a way into the inner sanctum of the river's mighty bosses.

The three most powerful urban water agencies in the Western U.S. are the Metropolitan Water District of Southern California, which supplies Los Angeles and San Diego, the Southern Nevada Water Authority, which supplies Las Vegas, and the Central Arizona Project, which supplies Phoenix and Tucson. As the drought wore on, the Big Three faced a deepening crisis.

Lake Powell and Lake Mead are essentially gigantic emergency water reserves: Together, they hold four years' worth of the river's average flow. But by 2007, both were nearly half empty. That spurred the Big Three's bosses to develop a set of shortage-prevention measures – voluntary conservation strategies to slow the reservoirs' fall and keep levels from dropping to the point where the system couldn't supply enough water to meet each state's yearly needs.

The crisis was part of a bigger problem that has long plagued the river: Bad math. The foundation of the law of the river, the 1922 Colorado River Compact, assumes that an average of 16.8 million acre-feet of water is available each year. But the river's actual long-term average flow is about 13 percent less. And computer models suggest that climate change will deepen that shortfall by another 10 to 30 percent by mid-century.

Shackled together by the very river whose water they had long reveled in fighting over, the water bosses began realizing that they might have more to gain through cooperation than through warfare. They also recognized that, to spread the impacts of the drought and soften the blow to their own agencies, they had to convince Mexico to agree to share in future shortages.

"That," says Patricia Mulroy, the blunt-spoken head of the Southern Nevada Water Authority, "was all-important to us."

U.S. water agencies have traditionally refused to concede any responsibility for the damage that Colorado River dams and efficiency projects have done to Mexico's environment and agriculture. "Any impacts that were felt south of the border were just not considered," says Kara Gillon, who represented Defenders of Wildlife in its 2000 case against the U.S. government. "It was like a no-man's land."

Robert Dundas
Robert Dundas Subscriber
Nov 07, 2013 12:29 PM
Has the "Tamarisk Beetle" been tried as a means of killing off Salt Cedar or Tamarisk in the Colorado Delta? We have had outstanding success with it along the Colorado River and it's tributaries in Western Colorado and Eastern Utah
Alexander Clayton
Alexander Clayton Subscriber
Jan 05, 2014 09:21 PM
After reading "Red Delta" some years ago, this is encouraging news in a very interesting article. I do question the statements about the 9% reduction in water deliveries to Lake Mead keeping the water level from dropping below the 1,075' threshold - how would reducing deliveries help that?
Sarah Gilman
Sarah Gilman Subscriber
Jan 17, 2014 09:48 AM
Thanks Alexander--Good catch. The error has been corrected.
--Sarah Gilman, associate editor
Richard Quartaroli
Richard Quartaroli Subscriber
Mar 20, 2014 11:00 AM
I am trying to find accurate mileage for the Colorado River in Mexico, Southerly International Boundary to the Delta. I realize the delta is ambiguous, given the lack of water, the sediment deposition, and the multiple channeling, but looking for something as close as possible. Perhaps Matt Jenkins, some HCN staff member, or a knowledgable reader might have some information. Thanks. RQ