This article evaluates the available water supply in the western U.S., along with the use of desalinization plants. Insofar as the United States mainland is concerned, it seems that there will be no substantial need or opportunity to use desalinization plants along the Pacific Coast. A need for these plants may develop along the Texas Gulf Coast when the lower‐cost natural waters are fully utilized. Inland in the seventeen western states, there will develop a great need for additional sources of water. This is an area with substantial quantities of saline waters, where agriculture, especially irrigated agriculture, has a prominent or predominant role in the present economy of each state. As natural freshwaters become fully developed, it will be difficult for agriculture, because of costs, to compete with urban and industrial demands for water. Any solution to water problems involving the production of freshwater from saline waters will have to be within the price range of those who need the water for irrigation. It seems that the high costs of disposing waste saline water from desalinization plants may, in many instances, offer an added problem in the use of inland saline waters as a source of freshwater. Lower costs for methods of extracting freshwater from the sea and inland saline waters are definitely needed.