They have found that current water practices are not sustainable, and many dramatic initiatives will be needed to correct the current unsustainable path the West is on.
Among those on the team are several researchers from Pac-12 schools, including Stanley Trimble of the University of California, Los Angeles, and Michael Campana, of Oregon State University. Glenn MacDonald, director of the UCLA Institute of the Environment and Sustainability, also is involved in the research.
Sabo and his colleagues applied the best available tools to data on water, soil, salt, dams, fish and crop yields. Some of their primary findings are these:
• Currently, the desert Southwest uses the equivalent of 76 percent of its total surface water to support its population. This will rise to 86 percent with a doubling of urban population (expected in 50 to 100 years). Sustainable balance for the region is achieved when 40 percent of total surface water is used.
• Salt accumulation, which results from the application of large quantities of water to grow drought intolerant food crops on desert farmlands, has likely caused about $2.5 billion in reductions in crop revenues in the Western United States.
• The water footprints of Los Angeles, Las Vegas and Phoenix are the top three in the United States. The footprint of Los Angeles alone is larger than the seven largest eastern U.S. cities (including New York, Chicago and Washington, D.C.)
“California is arguably the most important farmland in North America,” Sabo said. “But the water needed to support California agriculture (which is exported as food products to the rest of the country) is at odds with healthy populations of freshwater fish like salmon.
“Can we have salmon and tomatoes on the same table? Something will have to give.”
In an opinion piece published in the Los Angeles Times on Sept. 1, 2011, Sabo explained that balancing freshwater needs for farms, cities and ecosystems, in a region that is already chronically water stressed, will present difficult lifestyle choices.
Reclaimed water is central to the solution in cities, since half of all household use is for landscapes and much of the remainder is used to flush toilets, he said. Conversion of farmland under flood irrigation to a more efficient drip or center pivot application would save a substantial volume. The cost to farmers would be high, however.
“This cost would likely be passed on to consumers at top eateries and farmers markets in terms of higher food prices,” Sabo said. “The solution is tiered water pricing and increased water tariffs at home.
“We should expect to pay more for water in cities as they grow. This revenue should then be earmarked for financing startup costs for irrigation efficiency, reclaimed water systems and to buy back water for ecosystems.”
The opinion piece can be viewed at http://opinion.latimes.com/opinionla/2011/09/californias-water-wars-present-difficult-lifestyle-choices-blowback.html.
Sabo is an associate professor in the ASU School of Life Sciences. He and his team are part of a working group funded by the National Center for Ecological Analysis and Synthesis housed at the University of California, Santa Barbara. Scientists from Stanford and the University of Arizona also have been invited to participate.
Written by Sarah Auffret and Skip Derra
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