From Introduction: "The principal objective of this study is to digest the experience accumulated in the operation of the demonstration plants, and from this information, to arrive at the cost of fresh water when produced on a large scale. It is important to recognize that the costs, as calculated in this report, are based upon the state of development of the processes as exemplified and proven in the demonstration plants. The field is new, and the rate of development is such that further cost reductions may be expected."