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The water footprint of water conservation using shade balls in California


The interest in quick technologic fixes to complex water problems increases during extreme hydroclimatic events. However, past evidence shows that such fixes might be associated with unintended consequences. We revisit the idea of using shade balls in the Los Angeles reservoir to reduce evaporation during the recent drought in California, and question its sustainability by revealing the water footprint of this technologic water conservation solution.

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E.H. acknowledges funding from the Swiss National Science Foundation (grant number P2EZP2-165244).

Author information

E.H. and K.M. conceived and designed the study. All authors performed the research, analysed the data and wrote the paper.

Competing interests

The authors declare no competing interests.

Correspondence to Erfan Haghighi.

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Fig. 1: Number of shade balls and the volume of water used to produce them.