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Chapter II. Water - Present Uses and Future Needs The scarcity of water in much of the arid Pacific Southwest presents grave problems for the agencies concerned with fish and wildlife conservation. Programs to better fish and wildlife environments are severely hampered by back of water. Because of its scarcity in much of the arid Pacific Southwest, water for fish and wildlife takes on special significance. Its importance and relationships to such resources are sharp and distinct and it is axiomatic to think of these resources in terms of the location of water, its availability, and its quality. fortunately, many multiple-purpose projects designed and operated for such purposes as domestic water, irrigation, hydropower generation, flood control, and other uses provide much suitable habitat and hence many fish and wildlife benefits. Many of these benefits, however, could be materially increased by taking proper measures in the interest of wise fish and wildlife use. Some of these measures include the establishment of basic conservation minimum pools of adequate size, releasing flows at appropriate times, and the opening to fishing of reservoirs presently closed. The restoration of badly depleted streams offers other possibilities, and provisions the access should be incorporated into project plans wherever possible. The maintenance of fish conservation pools in numerous reservoirs primarily used for other purposes can largely be accomplished by coordinated operation during most years. Storage and withdrawals can be managed to minis the fishery use of the reservoirs. Extreme drawdowns in critically dry years will still occur in some reservoirs, but even they can be synchronized to some extent with rough-fish control measures. The required allocations of storage for fish conservation under coordinated operation of a large group of reservoirs are small. The water requirement for evaporation from such storage also are small. On the other hand, in the case of uncoordinated operations of individual reservoir operated by various individual agencies, the maintenance of minimum fish conservation pools may require substantial quantities with specific allocations in the reservoirs. While the larger multiple-purpose projects of the Pacific Southwest offer good possibilities for creating fish and wildlife benefits, the smaller single-purpose facilities and installations as a rule do not. In the broad spectrum of current water use in the arid Pacific Southwest, such fish and wildlife facilities and installations are supported by a slender thread indeed. Altogether too often the water they use is not commensurate with their importance. 7Epson Perfection 4870 Photo, 400 dpi, 8 bit, 13,590,528 byte