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Revival in the Colorado River Delta

This post is part of a series on the Colorado River Delta. So intimate was her connection to the river that as a girl she conditioned her hair with the soft mud from its channel bottom.  Her family fished in the waters and hunted in the dense forests of cottonwoods and willows that spread across the...

This post is part of a series on the Colorado River Delta.

So intimate was her connection to the river that as a girl she conditioned her hair with the soft mud from its channel bottom.  Her family fished in the waters and hunted in the dense forests of cottonwoods and willows that spread across the vast Colorado River Delta in northwestern Mexico.

For Inocencia Gonzalez, now seventy-seven years old and an elder of the Cucapá, a native tribe that has lived in the Delta for at least a thousand years, the Colorado River and the Hardy that flows into it, along with the lush landscape they both sustained, were life itself.Colorado River delta series

“There were fish everywhere,” Gonzalez recalled.  “And javelina, antelope, and bobcats.  We hunted rabbits, doves, deer, and Gambel’s quail.  And we ate the heart of cattail stems. It tasted like coconut.”

But Gonzalez speaks wistfully, for these are distant memories.

“When I was a little girl, the river never dried up,” she says. “Now that I’m old, yes, look, it’s dry…[I]t makes me sad.  There’s nowhere to fish.  There’s no fish.”

For millions of years, the delta of the Colorado River ranked with those of the Nile and Indus as one of the planet’s greatest desert deltas.  Towering riverside forests and lush freshwater and tidal wetlands spanned more than 3,000 square miles (7,770 square kilometers).  Vast fleets of waterfowl cruised through a labyrinth of lagoons, while songbirds crooned from the treetops.  Fish were so abundant the Cucapá ate it three times a day.

But then came the era of big dams.

Change in the Delta

Starting with Hoover, completed in 1935, a half-century of dam-building and canal construction to deliver water to the burgeoning farms and cities of the American Southwest sucked the river dry. Treaties promised more water to seven U.S. states and Mexico than the river usually carries in an average year.

And no flows were set aside to sustain the river ecosystem itself, including the verdant marshes, riparian forests, and estuarine habitats near the Colorado’s final destination, the Gulf of California.

The delta dried out.  Wetlands disappeared.  Most of the cottonwoods and willows died.  And year after year, the river failed to reach the sea, degrading not only the delta but also the estuary that serves as nursery grounds for the abundant fisheries of the upper Gulf.

The remnants of the delta constitute less than 10 percent of its original expanse.

Little wonder Gonzalez speaks wistfully.

“I would like for the river to rise again,” she says. “Yes, that’s the only thing I want.”

And while even a year ago, the Cucapá elder’s wish may have seemed nothing better than a pipe dream, a stunning turn of events has greatly increased the chances of her beloved river once again reaching the sea, and of her childhood forests making a comeback.

There’s a revival happening in the Colorado Delta – and it has only just begun.

Wetlands and Birds Return

Water sent to the delta after use by farms and cities is bringing wetlands to life where before there was only desiccated earth. For more than thirty-five years, a canal has discharged salty drainage water from an Arizona farming district into a remote part of the delta.  To everyone’s astonishment, it created – and still sustains – the Cienega de Santa Clara, a magnificent cattail marsh, teeming with bird life, and which now ranks as one of the most ecologically significant wetlands in North America.

A treatment plant built for Mexicali’s wastewater now includes 250 acres (100 hectares) of constructed marshland that not only further cleanses the water, it provides prime habitat for birds. In just three years, 160 species of birds have taken up residence, whether full or part-time.

And after the treated water is “finished” in the wetlands, it roughly doubles the flow of the Hardy River, which joins the Colorado close to the sea.

Farmers in the Mexicali Valley are playing a critical role in the restoration as well.  Working collaboratively with conservation groups, some are voluntarily selling their water rights to the innovative Colorado River Delta Water Trust – a kind of water bank for restoration efforts.  Established in 2008 by Mexico-based Pronatura Noroeste and U.S.-based Environmental Defense Fund and Sonoran Institute, the trust is paying fair market price for water rights, and then strategically using the water to reestablish forests along the Colorado River corridor and expand off-channel wetlands.

The endeavor is creating local jobs, even as it returns songbirds and a healthier landscape to the delta region.

Perhaps most amazing, the United States and Mexico have recently committed to providing more water to the delta over the next five years.  Together with the Delta Water Trust, the two governments plan to return, over a five-year period, some 158,000 acre-feet of water to the river system – about one percent of the Colorado’s historic annual flow.  It’s not a lot of water, but if managed strategically it could give a sustaining base flow and a rejuvenating flood pulse to the river’s corridor and delta.

Added up, this is a remarkable turn of events – and a unique opportunity.

Success over the next five years will pave the way for even greater revitalization, and for achieving the holy grail of Colorado restoration – enabling this iconic river to once again reach the sea.

And for Inocencia Gonzalez of the Cucapá – the “people of the river” – all may not be lost.

“I still hope to see the river come back, though others say I will die with the river dry.”

Help restore water to the Colorado River by joining Change the Course. Sign up online or text ‘River’ to 77177.

Special thanks to Silk and Coca-Cola, Charter Sponsors for Change the Course. Additional funding generously provided by the Walton Family Foundation.


Sandra Postel is director of the Global Water Policy Project and Freshwater Fellow of the National Geographic Society. She is the author of several acclaimed books, including the award-winning Last Oasis, a Pew Scholar in Conservation and the Environment, and one of the “Scientific American 50.” She is co-creator of Change the Course, the national freshwater conservation and restoration campaign being piloted in the Colorado River Basin.

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Meet the Author

Sandra Postel
Sandra Postel is director of the Global Water Policy Project and author of Replenish: The Virtuous Cycle of Water and Prosperity. From 2009-2015, she served as Freshwater Fellow of the National Geographic Society. Sandra is also co-creator of Change the Course, the national water stewardship initiative awarded the 2017 US Water Prize for restoring billions of gallons of water to depleted rivers and wetlands. The recipient of several honorary degrees, she works to bridge science, policy, and practice to promote innovative ways of securing water to meet both human and ecosystem needs.