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2922 x . see Narrows built if it would preclude further upstream development, especially in view of the flood \'ihich occurred on ::it. Vrain Creek and the Cadllla POudre hiver this past summer. Wr. C. O. Plumb re-emphasized that it would be more desirable to have upstream development and full utilization of Cherry Creek Reser- voir and referred to the negative benefits that would result from construction of the Narrows lteservoir. Attachment No.1 September 10, 1951 NARHOIIS DAM (Explanatory Statement by J. H. Knights, ~outh Platte District j~ager) Purpose Narrows Dam and lteservoir will serve the lower South Platte River Basin in a multiple-purpose capacity. Although authorized primarily for flood control, its usefulness for irrigation purposes cannot be disregarded. As new' planned, the reservoir will provide flood control and irrigation storage, with incidental sedi- ment, fish and wildlife, and recreation benefits. His tory Consideration has been give to providing a main cha~~el reservoir on the South Platte River in the vicinity of the i~arrows site since 1909. Irrigators connected vfith the early large-scale irrigation projects in the lower South Platte Itiver Basi,- realized that available off-channel storage Has only sufficient to regulate varia- tions in streamflow to seasonal irrigation and that a large-capacity reservoir was needed to balance flood and drought periods extendinc over several years. The dis- astrous 1921 flood in the ::iouth Platte -'iatershed em:::' -"ized the need for a large channel reservoir to provide flood controll'rotec".::":, _8:' +'helowervalley. b the early 30's and again after the 1935 flood, the Cor:_: JC' .nbineers made reconnais- sance investigations which disclosed the protection such a flood control structure would provide Ber the lower valley. j:ith the authorization of the Colorado-Big Thompson l:roject, the prospect of increased w<.ter supplies through return flOl':s became assured, but maximum utilization of flood and return flows could not be accomplished unless a reservoir such as Narrov,s were cor.structed in the lOher valle:. Authority for the dam was given by the general provisions of the Flood Control Act of 1944 as part of the Missouri tliver Basin ~lan of Development, The Narrows Unit was subseq'.iently included as a part of the comprehensive plan of the Flood Control Act of 1946 and was authorized for construction in 1941. , Selection of the Harrows ~ite The question is often asked, 11\:hy was it fOlU1d essential to have a reservoir on the lower reaches of the bouth i-latte River?" This question can be answered rather briefly: The Narrows Dam will conserve the flood fl01'ls origj,nating in the upper South Platte watershed, inclUding Bijou Creek, which noW pass the Colorado- Nebraska State Line unused. Unused flood flows do not occur every season but when they do they are apt to be of considerable magnitude; for example, in 1942 approxi- ,mately 810,000 acre-feet escaped unused,. A large-capacity reservoir is required