OCR Text |
Show able water resources within the basin and possibly, if necessary, through importations from the north coastal streams of California. Problems have arisen as to how much water should be released from reservoirs in order to satisfy prior water rights which are dependent on ground water replenishment from the stream channel. The Solano Project is an example of this. Such prob- lems often lead to considerable controversy because of the difficulty of determining how much water the ground water reservoir previously received from the stream, and the extent of ground water replen- ishment after the project is built. This is essen- tially a technical problem which must be met on an individual basis in local areas. Conclusions An appropriate solution of this problem might be through a Federal Government contract with the State or a. legal subdivision of the State, such as a conservancy district, which can collect special ad valorem taxes, and turn them over to the Federal Government in payment for ground water recharge. B. Conflicts in Beneficial Use 1. Conflicts of Fishery, Wildlife, and Recreational Interests with Other Water Developments The Problem Can fishery, wildlife, and recreational interests be made compatible with full use of water resources, and what principles should prevail in resolving conflicts? The Situation Water projects in the valley affect valuable fish and wildli£e habitat. These projects are harmful where favorable habitat and spawning grounds are destroyed, -when runs of anadromous fishes are pre- vented from reaching their spawning grounds, where fish and fish eggs are lost in irrigation and power diversions, and when the entire flows of rivers are diverted from their natural channels. They are lxarmful where some wildlife habitats are inundated, where marshes are drained, where dras- tic fluctuations in water level preclude the growth of aquatic foods for waterfowl, and where water 120 exchanges damage or destroy existing limited water- fowl wintering habitat. Water projects can be beneficial when they main- tain larger summer flows in the natural stream channels and reduce water temperature down- stream from the reservoirs. Fish may thrive under such conditions. Releases during critical periods can also benefit fish greatly. The fishery values of reservoirs themselves may or may not be equal in value to the stream habitat inundated by the reservoirs. Water projects can be beneficial by providing needed water to waterfowl refuge and management areas, by allocating some reservoir capacity to use for fish and wildlife, by manipulat- ing water levels for their benefit, by planting appro- priate plots and strips of food and cover for wildlife, by fencing select areas from livestock, and taking other desirable measures. One of the important problems to be solved in maintaining fish and wildlife resources is that of providing water for their use. In many localities both reservoir releases to stream channels for fish and water for waterfowl areas can be provided from existing and proposed water projects without undue cost and without seriously jeopardizing other proj- ect functions. Elsewhere, particularly in the San Joaquin Valley where water supplies are limited, adequate water for fish and wildlife often can be provided only at great cost or by reducing irriga- tion or power benefits. Furthermore, the California water code declares it "to be the established policy of the State that the use of water for domestic purposes is the highest use of water and that the next highest is for irrigation" (sec. 106). Any rights acquired for recreation and fish and wildlife will therefore have lower priority than irrigation requirements, and in cases of extreme water shortage the amount of water available to them may be curtailed. No commonly accepted criteria have been de- veloped for determining the extent to which water should be allocated to fish and wildlife in competi- tion with other uses. Monetary evaluations of the relative worth of water for fish and wildlife as compared with irrigation are unsatisfactory, pri- marily because of the difficulty in making the evaluations on a comparable basis. The problem of maintaining permanent pools for recreation purposes has appeared within the last few years. Past discussions between recreation and conservation interests suggest that serious conflict will not develop on reservoir projects where cyclic storage is the rule or where a minimum pool is to be |