Freshwater expert Sandra Postel
Photo by Virginia Smith

An Expert Opinion: Sandra Postel

Sandra Postel has been a leading authority on global freshwater issues for 25 years. Through her organization, The Global Water Policy Project, Postel conducts research, writes, and travels the world providing insights into water challenges and solutions. A former Pew Scholar in Conservation and the Environment, she is currently the National Geographic Society’s Freshwater Fellow —and she NEVER drinks bottled water if she can help it.

You’ve said in the future the human story will become a water story, what do you mean by that?

Water is going to be a central driver of the human experience over the next several decades and beyond. It’s about the scarcity of water; the fact that we’re running into limits in so many places around the world when it comes to water to grow food, water to keep cities expanding, and water to keep our populations supplied with what they need.

It’s been said “What oil was to the twentieth century, water will be to the twenty-first,” meaning conflict will erupt over water access.  Are wars over water inevitable?

Water glassI think water’s a more serious issue than the oil issue, given that there’s no substitute for water.  We can’t transition away from water, the way we can from oil to other sources of energy.  The idea that there will be wars over water the way there have been wars over oil; I think that’s a distraction.  There’s going to be enormous social unrest and many humanitarian crises around water and related food shortages within countries. We need to think about and plan more for these circumstances than worrying about armies mobilizing over water.  When you look at the river basins around the world, there’s more of a tendency to cooperate than to enter into conflict, so that’s a good thing.

I remember once watching David Letterman do a monologue when New York was in drought where he said, “I keep hearing about this water shortage so last night I turned on my shower and this morning it was still going strong.” How can you communicate about water scarcity when, in the first world, it’s pretty much available on demand? 

I think most people do only think about water from the point of turning on their tap.  But it’s hiding in so many other places in our lives; embedded in everything we wear, everything we eat, everything we do.  It takes about 2000 gallons a day to sustain the average American’s lifestyle.  More than half is our diet.  So helping people think about how their dietary choices increase or decrease their personal water footprint makes a difference.  Also, it takes 700 gallons to make a cotton shirt. That awareness is really missing.

Cotton field
According to the NRDC, it takes anywhere from 700 to 2,000 gallons of water to produce about a pound of conventional cotton; just enough to make a single t-shirt.

What have been some success stories in water conservation?

In terms of urban conservation, I think Boston is one of the best, in part because it’s in a part of the country that you don’t think of as needing to conserve so much. In the late 1980s, Boston was looking at a potential diversion of the Connecticut River to add supply to their reservoir.

The Connecticut River in western Massachussetts
The Connecticut River in western Massachussetts

But the citizens said they wanted to protect the river and its salmon populations, so they asked the water authority to take a serious look at conservation measures.  They did, and what they put in place was one of the most progressive and comprehensive conservation programs that I’ve seen.  It involved retrofitting homes, strategic pricing, education, audits of industries, fixing leaks.  A lot of older cities have tremendous leakage in the system.

Boston’s water use today is back to where it was fifty years ago.   It’s gone down 43% from the peak.  And this is greater Boston: two and a half, three million people.  The conservation program cost half as much as the alternative would have cost, and it is better for the environment. The river wasn’t diverted, and now there’s actually extra water, in a sense, surplus water in the reservoir.

Do you drink eight cups of water daily? What kind of water bottle do you use?

Photo credit: Cheryl Zook/National Geographic
Photo credit: Cheryl Zook/National Geographic

I drink tap water and I drink it out of a glass –or I have any number of stainless steel bottles that I put water in if I’m going to take a hike, or play tennis, or do something outdoors.  I don’t drink bottled water unless I absolutely have to because I’m somewhere where there’s no other water available.

You grew up on Long Island, but now live in New Mexico.  Does living in an arid environment change your relationship with water?

Sure. All I have to do is look out my window to see the importance of water in our lives.  Understanding the impacts of climate change, particularly on the southwestern U.S., and what it’s going to take to sustain agriculture and populations in the West – it’s all right here.

If you want to get an idea of your own water use, try out the Water Footprint Calculator Sandra Postel helped develop with the National Geographic Society. 

The Future of Water 2 October,2015Andy Soth

  • Nancy

    2000 gallons a day–just for me.
    A good insight as to the severity of the situation when one is reminded daily if living in an arid land. We’re semi-conscious here in Minnesota.

    I am proud to say that Leo House, where we stay in New York , will not allow bottled
    water. On our block, seeing so many students walking along sipping, it’s as if that
    early weaning from the bottle never worked.

    Truly enjoyed the Letterman quote–captures something about all of us.

    And thank you for the information about Boston!

  • Manofsteel11

    The US water sector is in need of restructuring.
    E&Y just released a report offering both a critical analysis and recommendations.$FILE/Cleantech-Water-Whitepaper.pdf

  • J Scott Martin

    All this is just more proof of poor water management. All these “Fellows” but no true engineers. We currently have flood conditions that could be contained and transferred to drought regions. Don’t be fooled, we do have the mechanical and technical means of doing so. The managers only see the hurdles and give up before even trying. The biggest hurdle and the thinnest excuse is always money. Containment just requires sacrificed real estate, again money lost in revenue. Transfer? The oil industry has been transferring by pipe line for generations. The reason it is being done so successfully is because of the great returns in revenue. The energy and time spent talking about a problem and not doing anything about it is just old news. J Scott Martin

    • geofly

      so you think it’s an easy matter to transfer billions of gallons of water cross-country and across mountains from wet areas to deserts? moron!

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Andy Soth

Andy Soth is a senior producer at Wisconsin Public Television based in Madison. His work has included environmental, technology and feature reporting for the magazine program, In Wisconsin, as well as numerous Web projects. He is content editor for, which was recently named best election Web site by the Wisconsin Broadcasters Association. The WBA, along with the Milwaukee Press Club and the Northwest Broadcast News Association have frequently honored Soth’s television stories. In 1999, Soth shared in a national Emmy as segment producer for The :30 Second Candidate.

Soth has an MS in Life Sciences Communication from the University of Wisconsin and graduated from Oberlin College with a degree in Art History. He has also attended the WETA Producers Academy and was recently selected a Fellow for the Institutes for Journalism & Natural Resources Asian Carp Institute.

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