Sandra Postel

Freshwater Conservationist

Fellow (2009-2015)

Denali National Park, Alaska

Photograph by Stacy Gold

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Photograph by Van Royko

Sandra Postel, founder of the Global Water Policy Project, is recognized as one of the world's most respected authorities on freshwater issues and is hailed for her "inspiring, innovative, and practical approach" to promoting the preservation and sustainable use of Earth’s freshwater. She is a Freshwater Fellow at National Geographic and co-creator of Change the Course, a national freshwater conservation and restoration campaign.

For more than 25 years, Postel has lectured, taught, and written prolifically on the geography of water stress and the implications for food and agriculture, rivers and wetlands, and regional peace and security. She views the world through a water lens and is often asked to provide the “big picture” in her talks—from the likely impacts of climate change on water supplies and of dams on freshwater biodiversity to groundwater depletion, water wars, food security, and the critical importance of conservation and better management to solving the world’s water problems.

Postel is the author of several classic books, including Pillar of Sand: Can the Irrigation Miracle Last? and Last Oasis: Facing Water Scarcity, which has been translated into eight languages and served as the basis for a PBS documentary. It was named a 1993 Outstanding Academic Book by Choice magazine. The author of scores of articles for popular and scholarly publications—from Science and Ecological Applications to Foreign Policy and Natural History—Postel is a frequent conference speaker and lecturer. She has served as a commentator on CNN's "Future Watch," addressed the European Parliament on environmental issues, and appeared on all major U.S. television networks and on National Public Radio, as well as in numerous documentaries, including the BBC’s Planet Earth and Leonardo DiCaprio’s The 11th Hour.

From 2000-2008, Postel was visiting senior lecturer in Environmental Studies at Mount Holyoke College and during the latter part of that term directed the college's Center for the Environment. She has served as consultant to the Nature Conservancy, the World Bank, and the U.S. National Intelligence Council, among other organizations. From 1988 until 1994, she was vice president for research at the Worldwatch Institute. She is a fellow of the Post Carbon Institute and an advisor to American Rivers.

Postel studied geology and political science at Wittenberg University, and resource economics and policy at Duke University. A Pew Scholar in Conservation and the Environment, Postel has received two honorary doctor of science degrees and in 2002 was awarded the "Scientific American 50" for her contributions to science and technology.


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    The Colorado River Delta Blues

    River deltas are among the most biologically productive ecosystems on Earth, and for millions of years the delta of the Colorado River was no exception.

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    Humanity’s Growing Impact on the World’s Freshwater

    As the human population has climbed past seven billion, and the consumption per person of everything from burgers to blue jeans has risen inexorably, the finiteness of Earth’s freshwater is becoming ever more apparent.


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    The National Geographic Society’s freshwater initiative is a multiyear global effort to inspire and empower individuals and communities to conserve freshwater and preserve the extraordinary diversity of life that rivers, lakes, and wetlands sustain.

In Their Words

I love nature—and water is the source of it all. I care about the mussels and fish and frogs that depend on water. The extinction of life pains me. I just want to do my part to be sure we humans conserve water and share it with all of life.

—Sandra Postel

Take Action

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    Change the Course

    Help us change the course and restore freshwater ecosystems by taking a simple, free pledge to reduce your freshwater footprint. For every pledge, we will restore 1,000 gallons back to the Colorado River.

Take the Pledge Today »


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    Save the Colorado

    Pledge to shrink you water footprint at home and by being more conscious of what you eat and buy.

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    Why Care About Water?

    Just less than one percent of the planet's water is available to meet the daily needs of nearly seven billion people.


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    Rivers run through the heart and soul of communities. But, increasingly, they run on human terms rather than on Mother Nature’s.

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