For 6,000 years, irrigation has ranked among the most powerful tools of human advancement. The story of settled agriculture, the growth of cities, and the rise of early empires is, to no small degree, a story of controlling water to make the land more prosperous and habitable. Pillar of Sand examines the history, challenges, and pitfalls of irrigated agriculture from ancient Egypt and Mesopotamia to twentieth-century India and the United States. By unmasking the risks faced by irrigation-based societies including water scarcity, soil salinization, and conflicts over rivers water specialist...