Inter-basin water transfers in the United States

Water supplies particularly for irrigation, in the arid and semi-arid western states of the U.S.A. depended largely on inter-basin transfers. Over the last 2-3 decades, the growing water shortages had stimulated interest in large scale, long distance water transfer schemes, four of which are discussed. The North American Water and Power Alliance (Nawapa) scheme involved redistributing huge amounts of water from the north west of the continent to the south. The economic and environmental costs would have been enormous, and the project was opposed by Canada from where most of the water would be taken. Economic and environmental costs, along with institutional, political and legal considerations, also impeded acceptance of High Plains transfers and the Texas Water Plan. The State Water Project of California was the only major inter-basin project to have been constructed (1960-73) in the U.S.A. Although it attracted considerable opposition, it did not involve crossing state boundaries and thus minimized federal involvement. In addition to discussing the institutional, political and legal considerations involved in large scale water transfers in the U.S.A., several alternatives ranging from conservation and efficiency measures to desalination and weather modification are considered. Despite the opposition, large scale interstate water transfers might become a reality.