Peak oil is the idea that the earth’s oil resources are coming to a close. But it’s not just oil that is disappearing, the earth’s fresh water supplies are dwindling and H2O is disappearing as an inexpensive commodity. We travel to the American southwest to see what the driest communities in the country are doing to keep the water flowing in the ever-burgeoning desert populations.

To see the full segment, visit http://www.pbs.org/kcet/wiredscience/video after original broadcast. Tune in to WIRED SCIENCE on your local PBS station (check local listings). For more information, visit http://www.pbs.org/wiredscience