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Post Carbon Institute

By Sandra Postel

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.

It takes water to make everything, and the explosion of demand for all manner of products is draining rivers, shrinking lakes and depleting aquifers.

Consider this—on average it takes 2,700 liters (713 gallons) to make a cotton shirt and 9,800 liters (2600 gallons) to make a pair of blue jeans. The cotton crops growing in farmers’ fields consume most of that water. A smaller share is used in the factories that churn out the clothes.

On any given day we’re likely wearing more than 15,000 liters (~4,000 gallons) worth of water. And if we slip on a pair of leather loafers, well, add another 8,000 liters (~2,100 gallons). It takes a lot of water to grow the grain to feed the cow whose skin is turned into shoes.

Such figures might not matter if there was abundant water whenever and wherever we needed it—or if water had a substitute. But water is limited, and there’s no substitute for it. We need water to quench our thirst, to grow our food, to cool electric power plants, and to make cars, computers and all those cotton shirts.

And that’s why the size of humanity’s water footprint—and of yours and mine—matters.

In a study published this week in the Proceedings of the National Academy of Sciences, researchers Arjen Hoekstra and Mesfin Mekonnen of the University of Twente in the Netherlands, have made the most detailed estimate to date of the scale and patterns of humanity’s water consumption.

This is a tricky and complicated task. Using a high level of spatial resolution, the researchers tabulated all the water from both rainfall and irrigation that’s consumed in making goods and services for the global population. To complete the picture, they added in the volume of water needed to assimilate the pollution generated along the way. They calculated the annual average global footprint for 1996-2005, the most recent ten-year period for which the necessary data were available.

The result is a large number—9,087 billion cubic meters (2,400 trillion gallons) per year. That’s a volume equivalent to the annual flow of five hundred Colorado Rivers.

Agriculture accounts for a whopping 92 percent of that global water footprint. Not only are crops naturally thirsty, we’re feeding more than a third of the global grain harvest to livestock to satisfy our desires for meat and other animal products. Added up, the average beef burger takes 2,400 liters (634 gallons) of water to make.

In fact diets heavy in meat largely explain why the average water footprint for the U.S. is twice the global average. U.S. consumers eat 4.5 times more meat than the global average.

One of the most interesting findings of Hoekstra and Mekonnen is that one-fifth of humanity’s water footprint travels across national borders in the form of “virtual water”—the water embedded in products that are traded between countries. For Egypt, Israel, Iran, Jordan, Saudi Arabia and other water-scarce nations, the ability to externalize their water consumption by importing wheat and other thirsty grains allows them to save their scarce water for industrial production and other higher-value uses.

Yet some water-stressed countries export a great deal of virtual water to other countries. For example, according to U.S. Department of Agriculture statistics, the Central Asian nations of the Aral Sea basin export 96 percent of the cotton they produce. Large-scale cotton production in this region over the last half century has caused the Aral Sea, once the world’s fourth largest lake, to lose 80 percent of its water. Much of the lake bed is now a salty wasteland.

The U.S., blessed with a vast area of highly productive rain-fed cropland, is the world’s biggest exporter of virtual water, sending millions of tons of grain to countries around the world. Its biggest virtual water imports come from China’s Yangtze basin, which produces a wide variety of goods for the U.S. market.

So what is a growing population to do to live within water’s limits and keep rivers flowing?

The short answer—consumers can alter their diets and buying habits to shrink their water footprints, and producers can use water more efficiently in making their products.

As corporations grow concerned about the risks water scarcity poses to their bottom lines, many are taking a careful look at their supply chains with an eye toward conserving water. Unilever, for instance, has helped Tanzanian tea farmers shift to drip irrigation so its Lipton tea bags have a lower water footprint. Patagonia, retailer of outdoor apparel, has gone a step further. Its eye-opening “Don’t Buy this Jacket” advertisement and its Common Threads Initiative to motivate companies and consumers to reduce, repair, reuse, recycle and re-imagine our world are helping to motivate water stewardship.

There are dozens more examples of organizations offering practical ways to shrink the size of our water footprints—from Meatless Mondays to the Alliance for Water Efficiency.

The movement to live prosperously while reducing our impact on the planet’s precious waters is beginning. The pace at which it unfolds is up to us.

For more information, click here.

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Sandra Postel is director of the Global Water Policy Project and lead water expert for National Geographic’s Freshwater Initiative. 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.”

American Rivers

Innovative financing and pricing flexibility are key to preparing the nation’s aging freshwater systems to handle growing demand and environmental challenges, according to a Charting New Waters report released Jan. 26 by The Johnson Foundation at Wingspread, American Rivers and Ceres.

The Financing Sustainable Water Infrastructure report, is the product of a meeting convened by The Johnson Foundation, in collaboration with American Rivers and Ceres, which brought together a group of experts to discuss ways to drive funding toward the infrastructure needed for the 21st century.

Largely built on systems developed during the 19th and early 20th centuries, U.S. water infrastructure faces profound problems of aging components, outdated technology and inflexible governance systems ill-equipped to handle current consumption, environmental and economic problems.

Presently, about 6 billion gallons of expensive, treated water is being lost in the U.S. each day due to leaky and aging pipes—some 14 percent of the nation’s daily water use. This pervasive water waste is underscored by the fact the American Society of Civil Engineers gives the nation’s water systems a D-, the lowest grade of any infrastructure including roads and bridges.

The report concludes that rebuilding and operating our water systems as they are presently built would be enormously inefficient. One major problem is the very nature of the systems themselves—where drinking water, stormwater and wastewater are built, financed and operated as entirely distinct units rather than as more efficient, interconnected systems. Another major problem is myopic, inflexible water-pricing systems that fail to distinguish between various water uses and generally undervalue water.

In order to achieve more sustainable, resilient and cost-effective freshwater systems, the report recommends bold new approaches for financing and operating public water systems, including:

• Local water solutions that can improve efficiencies, including green infrastructure, closed-loop systems and water recycling
• Flexible water pricing and revenue structures that distinguish between drinking water and various other types of water, such as lawn water and toilet water
• System-wide, full-cost accounting of water services and financing mechanisms
• Less reliance on state and federal funding and more reliance on private, market-based financing mechanisms that can support local, customer-supported solutions.

“While the deteriorating state of the nation’s water infrastructure is not a secret, we have lacked workable strategies and policies to finance the changes needed,” said Lynn Broaddus, director, Environment Programs at The Johnson Foundation. “This report addresses the critical linkage between financing and sustainability that was initially raised by the Charting New Waters consensus report in 2010. It’s not enough to pay for new water infrastructure—we need the financing to actually drive a new, sustainable water infrastructure that will take care of generations to come.”
 
Jeffrey Odefey, director of Stormwater Programs at American Rivers, said, “Clean water and resilient ecosystems are absolutely vital to our health, our communities, and economy. This timely report lays out clear directions to ensure that our communities grow into the future with safe, reliable water supplies and healthy rivers and streams.”

Sharlene Leurig, senior manager of Water and Insurance Programs at Ceres, said, “This report makes clear that our nation's water infrastructure system is broken and dramatic changes are needed. Rethinking how we finance and operate our vast water systems is not a choice, it's a must. We have the engineering and land use tools we need to ensure our water systems can stand up to 21st century challenges. The key will be partnerships and cooperation between business, government and public interest groups to finance these new tools.”

The Johnson Foundation is releasing this report as part of its work with Charting New Waters, an effort it formally launched in 2010 dedicated to catalyzing new solutions to U.S. freshwater challenges. Charting New Waters is composed of a diverse group of leaders from business, agriculture, academia and environmental organizations that have publicly committed to improving U.S. freshwater resources by advancing the principles and recommendations of the group. 

The initial phase of work led to the release of Charting New Waters: A Call to Action to Address U.S. Freshwater Challenges, a consensus report issued on Sept. 15, 2010. Download the report here.

As part of its ongoing Charting New Waters effort, The Johnson Foundation is also hosting a series of Regional Freshwater Forums that convene experts to examine freshwater challenges, successes, innovations and potential solutions that can bridge geographies and inform national policy. The first Forum took place in Denver, Colo., in October 2011.

For more information, click here.

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The Johnson Foundation at Wingspread is dedicated to serving as a catalyst for change by bringing together leading thinkers and inspiring new solutions on major environmental and regional issues. For additional information about Charting New Waters, or to learn more about The Johnson Foundation at Wingspread, visit www.johnsonfdn.org.

Ceres is an advocate for sustainability leadership. It leads a national coalition of investors and public interest groups working with companies to address sustainability challenges such as global climate change and water scarcity. Ceres also directs the Investor Network on Climate Risk (INCR), a network of 100 institutional investors with collective assets totaling about $10 trillion. For more information, visit www.ceres.org.

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