Preparing for a Water-Limited World

Global water expert and National Geographic Fellow Sandra Postel outlines the world’s water challenges in a new book published this week by the Post Carbon Institute (PCI).

“Our water problem turns out to be much more worrisome than our energy situation,” writes Postel , who is also a fellow with PCI.

The Challenges

PCReader-Cover.jpgWater, unlike oil, is critical to sustaining life and has no substitute, according to Postel.

“The global economy is transitioning away from fossil fuels toward solar, wind, and other noncarbon energy sources, but there is no transitioning away from water,” Postel writes.

Water is also where climate change will express itself most dramatically, as we’ve seen this year with damaging droughts followed closely by deadly flooding in Pakistan, where 1,600 people have been killed and 20 million more displaced by floodwaters since July. Or consider the decade-long dry spell that just broke in Australia and the recent overwhelming floods in the midwestern United States.

(Read more about how climate change is impacting the water cycle.)

Postel’s Post Carbon Reader chapter–“Water: Adapting to a New Normal”–warns that our existing water-management strategies are no longer valid in the face of climate change.

“The data and statistical tools used to plan $500 billion worth of annual global investments in dams, flood-control structures, diversion projects, and other big pieces of water infrastructure are no longer trustworthy,” she writes. “In other words, when it comes to water, the past is no longer a reliable guide to the future.”

The uncertainty of future water supplies and flow patterns is not limited to concerns over dams and diversions. Food security, public health, and life as we know it are also at risk.

Postel describes a “day of reckoning on the horizon” in the U.S. Southwest, for instance. Some scientists predict there is a 50 percent chance that Lake Mead, which stores Colorado River water for tens of millions of people and one million acres of irrigated land, will dry up by 2021.

And she notes that as much as 10 percent of the world’s food is produced through tapping too deep into residual and unreplenished groundwater resources. “This creates a bubble in the food economy far more serious than the recent housing, credit, or dot-com bubbles, for we are meeting some of today’s food needs with tomorrow’s water.”

The Solutions

“The water challenges confronting us locally, regionally, and globally are unprecedented,” Postel writes. The good news, she says, is that we have the economic and technological capacity to make sure global water needs are met. We just have to start using it.

The smarter path to water sustainability also requires us to work with nature and assign it a value for flood protection, water filtration, and other beneficial services it provides, according to Postel. And smarter water users-individuals, cities, utilities, businesses, and farmers-will be more aware of their water footprints and how to reduce them.

That could be through conservation, rainwater harvesting, different pricing schemes and policies, and more water-efficient toilets, energy production methods, and irrigation systems.

And the way to start is to buy local. “The more a community lives on water, energy, and food produced locally, the more options arise for solving multiple problems simultaneously, building resilience through resourcefulness, and preparing for future uncertainties,” Postel writes.

For more, read Postel’s chapter in the new Post Carbon Reader.


Tasha Eichenseher is the Environment Producer and Editor for National Geographic Digital Media. She has covered water issues for a wide range of media outlets, including E,The Environmental MagazineEnvironmental Science & Technology online newsGreenwireGreen Guide, and National Geographic News.

[This post has been reformatted for Water Currents.]

Changing Planet


Meet the Author
Tasha Eichenseher is the Environment Producer and Editor for National Geographic Digital Media. She has covered water issues for a wide range of media outlets, including E/The Environment Magazine, Environmental Science & Technology online news, Greenwire, Green Guide, and National Geographic News.