Australia's drought: lessons for California.

COMMENTARY Refl ective scientifi c treatises Strengthening citizen science LETTERS I BOOKS I POLICY FORUM I EDUCATION FORUM I PERSPECTIVES LETTERS edited by Jennifer Sills 28 MARCH 2014 sumptive activities—such as daytime lawn watering and car washing—to rules promot- ing efficient water use—such as require- ments for shutoff valves on hoses. Out of those temporary restrictions, permanent restrictions grew. Some areas in Australia still restrict daytime sprinkler use. Perhaps most relevant for worried Californians is how the Australian public received these changes. Studies cite an overall spirit of goodwill and cooperation fostered by the stress of drought (6). The Millennium Drought brought about profound changes in Australians’ concep- tion of the environment, climate change, and water. The sticking power of those les- sons and the success of the resulting policies and strategies will be tested by the next big drought. One lesson California can glean from the Australian experience is empower- ment. Individuals making frugal water deci- sions can make a big difference in urban areas. Water markets and other measures that increase the fl exibility of irrigation farmers in their response to drought can have big payoffs. Sustaining critical environmental water requirements will provide the basis for postdrought environmental recovery. A spirit of cooperation rather than contention can prevail even when tough decisions are made to address the needs of farmers and city residents. AMIR AGHAKOUCHAK, 1 * DAVID FELDMAN, 1 MICHAEL J. STEWARDSON, 2 JEAN-DANIEL SAPHORES, 1 STANLEY GRANT, 1,2 BRETT SANDERS 1 The Henry Samueli School of Engineering, University of California, Irvine, Irvine, CA 92697, USA. 2 Melbourne School of Engineering, The University of Melbourne, Parkville, VIC 3010, Australia. *Corresponding author. E-mail: amir.a@uci.edu References 1. A. I. Dijk et al., Water Resources Res. 49, 1040 (2013). 2. Z. Hao et al., Sci. Data 1, 1 (2014). 3. S. Dolnicar, A. I. Schafer, J. Environ. Manage. 90, 888 VOL 343 SCIENCE www.sciencemag.org Published by AAAS Downloaded from www.sciencemag.org on March 27, 2014 MOST OF CALIFORNIA IS SUFFERING FROM AN extreme drought, and storage levels in the major reservoirs are well below historic lev- els. For the past several months, an unusually stubborn ridge of high pressure off the West Coast of the United States has been blocking normal winter storms and the rain they carry. California’s history of drought has led to state- wide strategies to save water, but Californian residents and policy-makers can do even more: They can look to the story of Australia’s experi- ence with a drought so intense and long-lasting that it was dramatically dubbed the Millennium Drought (1). The Millennium Drought lasted from 1997 until late 2009 (2). Australia’s economy and environment were hit hard. The drought accel- erated the same trends facing farmers in devel- oping countries worldwide: Small farms were squeezed out. Midsized farms were most vul- nerable because they could neither achieve the economies of scale available to larger produc- ers nor buffer losses with off-farm employ- ment like the smallest farms could. Amazingly, despite blows to crop yields and Dried out. As of February 2014, most of California is in Extreme to Exceptional Drought (see red and livestock numbers, Australia’s rate of growth in dark red areas on map). agricultural production has quickly returned to predrought trends. The impacts of this major drought on irrigation communities were buffered by some critical water reforms. These included: (i) well-developed water markets that allowed water trade to farmers in the greatest need; (ii) modernization of irrigation infrastructure that increased the effi ciency of water delivery; and (iii) establishment of clear water entitlements for the environment that protected critical refuge habitats and populations as water availability declined. The use of water markets was particularly critical. More than 40% of annual water alloca- tions were traded at the height of the drought in 2007. For example, increased water prices allowed dairy farmers to sell their allocation and purchase fodder with the proceeds rather than irrigate pasture. Fruit growers and other producers who needed to maintain irrigation through- out the drought could purchase the dairy farmers’ water to keep their operations viable. In urban areas, strategies to increase supply and decrease demand were brought to bear. Expensive desalination and water recycling plants were built. Australians were more comfort- able with the desalinated water (3, 4), despite the recycled water’s safety and the desalination plants’ greater cost and large carbon and environmental footprints (4). Between 2002 and 2009, per capita municipal water use in southeast Australia decreased by nearly 50% (5). Water use restrictions ranged from outright bans of conspicuously con- CREDIT: DATA FROM THE GLOBAL INTEGRATED DROUGHT MONITORING AND PREDICTION SYSTEM (GIDMAPS) (2) Australia’s Drought: Lessons for California