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Formulatirln of Alternatives The end-p duct of the project element identification and selection process was a list of the project elements best suited to s rving the irrigation requirements of the study area. These elements were then combined into various alternative projects for further evaluation. The alternatives were developed to provide some or all of the functions. oposed in the 1985 reconnaissance study and to be complementary. This last criteria meant that the alternative 'were structured so that the construction of one of the smaller alternatives would not preclude the later cons :uction or hamper the intended functioning of any of the other alternatives. In addition, the alternative were formulated to minimize both the cost to construct the facilities and the cost to operate the system. The criter established to guide this study specified that the High Elevation System proposed in the 1985 reconnaiss nce study was the maximum system which could be considered. The reservoir sizes recommended in the 1985 r 'connaissance study were, therefore, the maximum considered in this study. The reservoir capacities proposed i this study provide very little carry-over storage from one year to the next. The 80 percent reliability criterion a d the assumed cropping patterns indicate that carry-over storage would not be higWy beneficial for cash crops but would instead be a very expensive source of water for marginally irrigated grass hay/pasture. In addition, a :review of the proposed alternatives indicates that enlargement of the reservoirs for carry-over storage would be p ysically impractical or incompatible with other plan elements and would increase costs significantly. The prod ct of the project formulation process was four alternative project configurations designated as Alternativ s G, L, Hand W. These projects represent various levels of development, with Alternatives G and L being the ,implest systems, Alternative H being a combination of G and L and Alternative W the maximum system. TIlCse alternative project configurations are described subsequently. Descrlotio of Alternative Protect Confl~uratlons The four ternative configurations developed in this study were formulated so that they could be implemented using a st ging sequence. Using this process, Alternatives G and L were formulated so they could function independe 'tly or be combined with additional elements to form Alternative H. Alternative H combined with additional 'Iements comprises Alternative W, the maximum alternative considered. This formulation allows flexibility s. that an alternative selected due to financing constraints could be expanded into a larger alternative when addi 'onal financing becomes available at a later date. This could be accomplished by simply adding the remaining lements of the next alternative system. V.7 I I I I I I I I I I I I I I I I I I I .