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38 39 is \) years, with storage in t.be Na.ITow,:; Reservoir starting about 9 months before completion of the dam. The construc.tion schedule for the remaining recreation rB.cilitie,,':~ will be determined by the Rod- ministering tLgency primarily on an lias needed" basis. Construction of the UnlOn Pacific Railroad l'elocf\.tlon would be necessary beCo!'e construc.tion on the da.m could be started. Negotiations with tbe rail- road, field\\:ork, design, and preparation of specifications w01lld require about 2!4 years befor~ tbe railroad relocation contract could be awarded, Construction of tbe dam could start about 2% years later, Rigbts-of-way are scbeduled to bo acquired as they are needed, ALTERNATE PLANS of tbe Weld County site at $45,459,000. At tbe time of tbat estimate detailed geologic invest.igat.ions were available on the N allOWS site! but only limited information was A.\'nilable on the Weld County site: III the ease of the cost ana.lyses, thereCore tbe e.stiwutes indica.ted 8 definite advantage in the favor of the Na~ows site f.o tbe extent DC about $7 million, It was tbe opiniou of tbe staff of tbe Colorado Water Conservation Board, shared by n~allY otbers, that the geologic in \'estigations at the Weld County site were insufficient to mfl.ke a fa.ir comparison between tha~ site a~d th~ Narrow~. Tbe board, thereCore, employed tbe consultl1lg engmeerlllg firm of Woodward-Clyde-Sberard & ASSOCIates to conduct additional geological inve;;tigations at tbe Weld County site tmd to moke percolatjon tests at both sites. The Bureau of Reclamation o~sisted in t.hese aclditional investig-ations. At tbe conclUSIOn of these new investigations the consulting firm rendered a report to the board on March 11 1964 sta.ting conclusions essen tially as follows: ' , L That, tbe percolation of water througb and around tbe dams aL either SIte. would be essentinUy the same unles9 positive cut.off was aC'.comph~bed. 2, That positive cutoff could be accomplisbed at the Weld County ~ute but could not be accomplished 'Lt the Narrows site. ,3, That (rom purely geologic considerations the Weld County SIte was preferable to the N lIIrows site. Based upon cbe inforr:nation contained in the consultant's report., the Bw:eau oC Reclama.tlOn was ~eq~ested.to make new complU"ative cost est.lilJA-teg. of tbe two re."ierVOll" Sltes, WIth the understandmg that I these new est1ilJates would be reviewed and reported upon bv the consultants. ~ I Tbe' information presented by the consultants indicated tbat tbe alluvial deposits along tbe uxi9 of the Weld County site extended to a grefL.ter dept.!) than WHS originally estimated, but that positive clltoff cOlud be obta'!'ed by complete excavation and replacement of tbese allUVIal ma.tenals. Because of the direct downstream flow of water WIder the dum foundation if positive cutoff WtlS not made the Office of tbe Cbief Engineer, Bureau of Reclamation, conelud~d tbat for s~fety reasons a dam sbould not be constructed at the Weld County site lIDless J.>o~Itlve cutoff was assured. The new estimates wero prepared on t.bis basis. .Thr.re ~\'f\.S considerable di~satisraction by some valley residents with the ngbts.of-way costs '\-'1thin the two reservoir sites as originally computed by the Bureau of Reclamation, Tbe Colorado Water Con- servadon Board tben employed tbe firm of Justin H, Haynes & Co, to estima.te the value of hmd to be acquired in fee, flood easements, and severance damages iLt each of the two reservoir sites. A documented report from that firu; was rende,red t.o the board under date of M8.Y 1, ] 964. The report estlmnted the costs oC acquisition a.t th~ Narrows site at $.5,787,000, aud the Weld County site at 53,750,000, This c,ompared to the Bureau's est.Imated CO:'ils or $4,238,000 at tnt' Narrows site o.nd $3,544,000 at tbe Weld County site, Those COSl9 do not include a1l0w- ,?-nces for clllltjIlgencies, engineering, and overbef\d. Final estjmates !nc}ud e slIch n1Jowances !ind increased the costs by about 50 percent. . The report of the nppraIsal consultants was lIsed by the Bureau of Reclamation in its reanalysis. Weld County Dam and Reservoir site On April 18, 1958, a group of about 35 residents from tbe Soutb Plat.te Valley, representing aretl.S extending generally from just below Denyer to the State line, appeared before tbe Colorado WaLer Con- servation Board at. a regular meeting jn Denyer and requested the board to reinitiate studies leRding toward the construction of channel stora!,e on the Soutb Platte River, The board agreed to this request and III tbe years 1959-63 it furnisbed $82,950 tu tbe Bureau of Reclamation for further studies of tbe Narrows 1wit. Because of local interest in an upst.ream site, the Bureau of Ree-Iama- tion was requested to make B. hydrologic and C03lt compari9on of the Narrows and Weld County (Hardin) Reservoir sites, Tbe upstream Weld County site is about 23 airline miles from the Nt\ITOWS site. In February 1963, the Bureau documented tbe results of its hydro- logic studies in a publication entitled "Site Selection Presento.tion to t.he South Plo t.te Steering Committee." The essence of the conclusions set fortb in the presentation were to the effect that neither site had a . dear-cut hydrologic advantagc over tbe other site) under either his- toric or expected 1990 flow conditions. St.ora.ge Rt the :r\RITO\\"S site provides a more adequate supI,Jly for the lower basin while storAg-e at the Weld Couat}' site prOVIdes a more adequate supply for the midsection of the basjn. The. bydrologic conclusions drawn by the Bureall were studied extensIvely' by tbe staff. of the. Colorado Water Conservation Bo~rd \" h ch ndicated no major dISAgreement OIl the hydrologIC st,udIes. The siudies disclosed that a resen-oir at tbe Weld County site would reduce annual \-alley water sbortages about 2,500 acre-feet more than tbe Narrows site under tbe present time lcvelllnd would reduce short- ages 9,000 acre-feet more annually under Lbe 1990 time level. Off- setting the economic advautages or Luis u.dditional water supply at Weld County was tbe fact tbat the flood control benefits would be greater at the N a.rrO\l;S site. It appeared that the combined purely economic values of water conservat.ion and flood control a1, either site, for all practica.l purposB.G, were ide.nt.ical. A selection or olle site in preference to the other, b5Sed upon combined hydrologic a.nd flood control considerations, was t.here!ore eliminaLed. The remaining major item in tbe site selection was tbe ma.tter of compllrative costs. In a report entitled ",site Selection Report, Narrows Unit-Colorado" dat.ed SeptEmber 1961, the Bureau esti- mated the total cost of tbe Narrows site at $38,334,000 and the CdSt