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Water-quality and Waste Management Inventories of salt loads.-- There are proposed: (1) over an initial five-year period, a reconnaissance estimate of the natural salt loads carried by streams of the region and of the changes in load (usually increases) caused currently by irrigation, by industries, and by municipalities; (2) thereafter, by successive sub-basins or development areas, recurrent specific determinations of the man-caused changes in the salt loads of streams. This would entail about 10 primary chemical-quality stations and perhaps 50 roving stations maintained for five-year intervals at each particular site. Cost, first year $90,000, second to fifth year $250,000 per year. Means for water-quality management.-- A most crucial goal of water management in the region should be to seek out all possible means--chemical or physical--to counter the depreciation in water quality that results inevitably from water use. South there would be a means particularly adaptable to depreciated waters which, if improved but moderately in quality, could be reused without restriction. For example, means for precipitating some part of the dissolved solids, or for segregating a relatively large fraction of the waste products in a relatively small fraction of the water that then could be disposed of separately. This would involve intensive research into fundamental water chemistry, including neutron activation of contaminated waters and of base-exchange materials. Difficulties admittedly are serious but the stakes are great and a practical method would be applicable universally. From five to ten years of intensive effort is contemplated. Cost, excluding possible tests at pilot-plant scale, first year $25,000, second to fifth year possibly to as much as $150,000 per year. Water Salvage Some of the hottest and most arid areas in the United States lie within the Pacific Southwest. The growing season is nearly continuous and the semi-tropical climate is favorable to luxuriant growth where water is available. Evaporation and transpiration rates are extreme and, over the region as a whole, probably dissipate at least 97 percent of the sparse precipitation. Under present technology this dissipation of water cannot be diminished economically. If an economic means can be found by intensive study, however, the amount of usable water locally might be increased several fold. 9Epson Perfection 4870 Photo, 400 dpi, 8 bit, 14,325,760 byte