ABSTRACT
Taken as a whole, our civilization has adapted over the last 9,000 years to the distinctive — and relatively constant — pattern by which the earth continuously recycles water between the oceans and the land through evaporation and runoff, distributes it in the form of precipitation, river flow, and the movement of creeks and springs, then gathers and stores it in lakes, swamps, wetlands, underground aquifers, glaciers, clouds, forests — indeed, in all forms of life. Fresh water in particular, and lots of it, has always been essential to the viability and success of any civilization. From the first irrigation networks along the Nile more than 5,000 years ago, to the Roman aqueducts and Masada cisterns, to the monumental system of tunnels that bring fresh water daily to New York City, human civilization has displayed remarkable ingenuity in assuring an adequate supply of water.
