"Key West is one of the U.S. cities most vulnerable to sea level rise, and so it's adopting regulations requiring new homes to have freshwater cisterns and to be built higher than the current flood plain level."
"Florida — especially South Florida — is very flat and very low, and in places like Miami Beach and Key West, buildings are just three feet above sea level. Scientists now say there may be a three-foot rise in the world's oceans by the end of the century.
Under ordinances recently adopted in Key West, all new buildings will have to be raised at least a foot and a half higher than the old standard, use green building codes and have large, freshwater cisterns. The water will be used in gardens, swimming pools and toilets. By collecting rainwater, cisterns help reduce flooding by keeping it out of the streets."