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saltbush, willows, and other plants occupy over 0.5 million acres of land along the flood plains of the rivers. Investigations show that it would be feasible to salvage some of this water by the eradication of the phreatophytes. These plants, in some cases, annually use 50 to 100 percent more water than most irrigated crops, Estimates of water use and salvage are only approximate. Continuing studies are necessary to determine practical methods for elimination and control of this high water-using plant. At the present time there is a great deal of research being conducted at various universities, and cooperative studies are underway by several governmental agencies to determine actual bareground evaporation and the transpiration rate of river-bottom vegetation. Evaporation losses from the wet channels of ephemeral streams following floodflows are known to be great. This is attested by the observed decrease in unit runoff as drainage area increases. The practicability of increasing recharge to ground water by ephemeral streams depends to a great extent upon the hydrologic regimen of the stream channels. Research in General Hydrology--Long-range research in general hydrology has two distinct functions--to improve the design of proposed irrigation works and to encourage more efficient use of water for specific purposes and the salvage of waters now used non-beneficially. Studies of this nature have been carried on for several years. Long-range programs have been developed for continued study and research in these fields. In the field of improvement of design, there are scheduled studies on hydrometeorological investigations, research in sediment transport, and stream hydrograph analysis. The hydrometeorological investigations deal mainly in the improvement of techniques used in the determination of maximum probable precipitation to be expected above potential damsites in the Lower Colorado Basin. This maximum probable precipitation is used in developing the design storms which are in turn used to develop the design flood for determination of the spillway capacity to insure safety of the structure. In many instances the spillway is one of the more expensive features of the dam, and it is necessary that as much be known about the flood potential as possible. Sediment transport studies are necessary in designing a storage system, as a significant proportion of the storage space provided in reservoirs and streams, such as the tributaries of the Lower Colorado River, is needed for the storage and control of sediment. It is necessary that we have a reliable estimate of sediment transport on the streams to properly determine this space requirement. IX-6Epson Perfection 4870 Photo, 400 dpi, 8 bit, 14,155,776 byte