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yield for different storage approaches may be different. The study must compare alternatives that can provide equivalent yield, not equivalent storage space. The currently accepted average long-term yield is 7,000 acre-feet from the 20,600 acre-feet of storage space. Yield for a specified quantity of storage may also vary from one water user to the next for several reasons such as seniority of a water right and the timing of when water may be withdrawn. (4) Level of Detail in alternatives analysis. A 50 year period of analysis should be used for all alternatives. For the RR/EIS, sufficient detail on existing water supply, water demand (including future demand) and the no action and least cost approaches to meeting the demand must be provided to allow the Corps to evaluate the financial feasibility of storage proposals (20,600 and 7,700 acre-feet. There was discussion of the need to roll up the various users' demands and alternative strategies without getting too hung up on individual relative seniority rights, while comparing alternative costs for comparable yields. There is no need for a separable cost remaining benefit analysis (SCRB), particularly assuming the only purpose is M&I water supply. The overall analysis requires only that figures be at a reasonable level of detail for the analysis being conducted and that each alternative be at similar levels of detail. The cost of the "least cost no action plan" based on a good "reconnaissance level cost estimate" and accompanied by significant explanation within the report should be sufficient. With specific regard to the 7,700 acre-foot alternative and assuming linear growth in demand and that the 20,600 acre-foot alternative meets the community's needs for 20 years and the lesser alternative meets the needs for 10 years it would be reasonable to add the first 10 years of the no action alternative to the smaller storage alternative to estimate the components and cost of meeting the 20 year demand period. It would not necessarily be reasonable to add half of the no action cost which would be inflated to the extent that future water demand will be met by more numerous and deeper more costly wells. D. Analvsis ofER. (1) Needs Statement. It was determined that further limited coordination by the Project Delivery Team (PDT) with Division staff would be needed to ensure that the "Needs" statement is sufficient. Per Corps policy for reallocation studies, the need as currently defined in the Reallocation Report/ Environmental Impact Statement (RR/EIS) is not believed to be adequate. It provides background and future supplies for the metropolitan area and does not provide specific information on current supply, current demand and future demand of the entities actually requesting storage for M&I water supply purposes. This approach does not appear to provide sufficient information for the evaluation of the no action 6