Capturing rain may be one of humanity's most ancient methods of acquiring water, but now it's coming back in vogue. Rather than press their luck with drought, conservation-conscious homeowners are setting up rudimentary rain barrels and elaborate rainwater storage systems to catch precipitation for nondrinking purposes, such as watering their lawns. But while rainwater may seem like a global common, nowadays it depends on where you live: By capturing rainwater, some homeowners are breaking the law. This has put city and state governments in an awkward position—smack in the middle of competing water users and advocates, often from within their own agencies, of conserving water to protect supplies
