According to a report by the United Nations (World Water Assessment Program 2009), the surging growth in global population has led to a rapid increase in the world’s water demands. A large part of these water demands stem from food production requirements, irrigation being a prominent component in the requirement. Approximately 40% of crop production comes from the 16% of the agricultural land that is irrigated (Gleick 1993; Postel et al. 1996; Tilman et al. 2002). However, the agricultural land would not be sufficient for providing food for the world’s population if not for water from rivers, lakes, reservoirs, and wells; in fact, about 60% of the world’s freshwater withdrawal is used for irrigation purposes (Oki and Kanae 2006). Thus sustainable management of water resources is required to meet the growing global water demand.