The Department of the Interior's WaterSMART program will save enough water for a smallish city — 400,000 people — yet it cost only $24 million. As Tina Casey reports at CleanTechnica, the program works by going for the low-hanging fruit: 54 separate programs that address everything from farm irrigation to water distribution infrastructure.

At $60 per person, the programs are way cheaper than finding an equivalent amount of water by pretty much any other means except dowsing — especially in the arid Southwest where there isn't any more water to be had. One of the grants simply helps defray the cost of converting open ditches into pipes; another helps a water district in southern California use high-tech mapping to identify places where it can conserve.

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Of course, another way to incentivize water conservation would be to price water appropriately, instead of the insane system we have now, in which a hierarchy of "water rights" allows some (mostly agricultural) users to draw as much water as they ever have, and at a super-low price.

As one water expert at the National Center for Atmospheric Research told this reporter: "We don't have a water crisis in California, if you just look at it from the perspective of water use in cities. What we can't keep doing is growing alfalfa in the desert."