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u. s. BUR~~AU OF RBClJll,IATION REPORT (eOlIT 'D) just above the storage level reserved for irrigation purposes. Additional dam protection is provided by rock borrmv pits to from an emergency spillway of 2,500 sec. ft. capacity. For details of the construction fea tures and estimates of construction costs, see attached drawings and tabulations .vhich have been reproduced from the Bureau Report. Also attached is a map shcw{ing topo- graphy at the reservoir site. 'ilith spillway outlet at elevation 6462, or 107-feet above the stre~~ bed, storage capacity is 8,000 acre-feet. Of this capacity 1000 acre-feet is reserved for sedimentation and 7,000 acre-feet is allo- cated to irrigation. Above that point, to the top of the dam (elevation 6,520) total storage is 35,400 acre-feet, thus a.l.lovring 27,400 acre-feet reserved for flood control. Total cost of the Castlewood Dam, including construction costs and rights-of~vay, is 0876,500. The B~reau recommends that ()429,500, or 49 percent, be charged to irrigation (40-year interest free repayment period), and ::447,000, or 51 percent, to flood control. It ~ill be noted, from the Bureau Report, first, that whereas irrigation may use but 20 percent of the reservoir capacity, those interests are expected to repay 49 percent of the costs; and second, the Bureau "made no studies of flood control benefirs". If irrigation charges had been allocated in proportion to total or usable capacities, the irrigation obligation~ould have approxi- mated 0175,000. To increase the capacity of a flood control reservoir such as TIould be needed, per Bureau desicns, at Castlewood site, sO as to -11-