Across the sun-cooked flatlands of the Imperial Valley, water flows with uncanny abundance. The valley, which straddles the U.S.-Mexico border, is naturally a desert. Yet canals here are filled with water, lush alfalfa grows from sodden soil and rows of vegetables stretch for miles.

Within this grid of greenery, near the desert town of Brawley, Mark McBroom grows 6,000 acres of hay crops, like alfalfa, and fruit orchards, all irrigated by water imported from the Colorado River.