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~nl;" ". ;;;,; .:VV . . Answer: In studyin~ the water available to the Narrows Reser- voir, fourelements were cOllsidered us making u:? the inflow to the reservoir. First of these is the hist~rical flow ~t Kersey; second, the net ~ain in the stream in the re~ch from Kersey to the Narrows; t~ird, anticipEl. ted return flows from Colorado-Bit; T~lompson Project; Elnd fourth, anticipated return flows from the Blu~-So'lth Platte Project. Under tite terms of Article 19 of the con~ract ~eb<een the United States and the Nortl1ern Colorado YjateT' Conservancy District, use and reuse of return 1'10'1,'"5 which mic;ht develop from the Colorado-Big 'l'ho:Tlpson Project we~~e dedicated to use by the Conservancy District. In mal,ing the w~t"r su)ply studies for the Narrows and oJserving the terms of this contract, t;."e aSS\..lli'l.ptiDn was made that t:le only 'Nhter whicn '~{uuld be available to the Narrows Reservoir would be that in excess of the amount requ.ired to satis- f~' pres.3nt appropriators holding direct flow rigi-:ts and after a}.l existin.g storGl.ge rigllts were fi lled. l/i8.ter remaining surplus to th.e [...boy€?- noeds WCtS considered us available 11S storable water in the 1,;urrO\'lG Unit. T.iw policy 1'oll0\ved in makint: the water studies is that vlater c.ccrlling to l~Ctrrows should be first used to fur.11).sh a supplern.ental supply to current- ly irrigo.ted lc.nds in tile South ?la~te Valley. '\,,,ter remaining o.fter t'1is is 'done should the:l be Q'JQibble for irrig<ltion "f new lands in the South Platte Valley. Tile 6tudy of wL\te,' sl.'pply for tne Nnrrows we.s me.de for the period 1925 to 1945, inol'"sive, t\nd si:ows an avero.ge of 110,000 wcre-feet nvuilnblEJ for stor::lgE:: in tLe Enrrows. The M:01J,at in inriiYidunl yef'.rs v.:~ries from n low or no nore-foot to .:l high 'Jf 348,D(";0 ficre-fect. ThGse fif-urns fire those ostinnted for cor.ditions that would pre',cil e,fter complotion of the Blue-South Ph,tte Project. It is necess~ry to firm up the &crrows sUDPly in order thD,t sufficient capo.city will be "voile.ble nt No.rrows for conservntion purposes to Qllow- the c:.~rrj'over of wa..ter fro," wet y""rs to dry yec.rs. 2.. QU0stion: !lns the B'.lreo.u fully evaluatod tho "mount of pump- in[; by irrig;,,-fiQll wG11s in tho "'ren supplied by ditches from the Soutn Pllltto River, Answ.Jr: This question conccrnin~ full eV:lluation is rcther difficult to answer in tl,at w:16n <Jealing with certain intangibles, such as the amount of recharge which may be marle tn any part.icular water- benring, aquifer, the amount of safe yield of such G.qiJ,ifer Goes not lend itself' to an exact analysis. The Bureau l1as attempted to evaluate possi- ble future recharGes and 2umping by irrigation in the service area of the Blue-South datte Project to th€, be~t of its ability and wi"',hin the accuracy to which such analysis is possible with aVuilable informatio~. The amount of' return floVl which will reach the ri.ver above the j;arrows ;;eservoir as a result of o::>eration of the l;lue-South Platte Project has been estimated after considering the effect of pum~inb in the service area. The United States Geological Survey investigations in cooperation with the Bureau are ~ow in progress and the first progT8Ss re~ort has been iss~ed and is now available. 3. Question: nas the aureau estimated the amount of return flow used in sta~il'izing ~he South Platte River from the transmountain diver- sion that will be utilized by existing irrigation systems? 5