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." ( This ....ill maintain the Colorado River reservoirs 1n a Eull Or near full cQ:1cit.ion. During this ?eciod, an~ dra....oown in :ese::-..."oir: stocase .....~.:.ch occurs as a ~esult of belo~ a....e~age annual ~ater se~~l~ is likely to ~e only temporary_ Such years, 'follo\"'ed S~ ~ear normal or above normal runoEf years, in which supply ~ill exceed consumptive uses by the Basin States, ....ould result in refilling of the resevoirs. A firm cornmitme~t for uninterrupti~le delivery of ~atec in excess of basic apportionments throughout an entire calencar year, whether surplus or unused appor tionments, can be measured aga,inst any risk to reservoir storage. So long as the lo~er 3asir. states consumptive use needs are less than 7.5 million acre-feet per year and the total Basin consumptive use is less than the long-term avera~e rive~ supply, there '.'ould ~e little or no ri'sk to long-term st.occg-= from .=:nnual uninte"rruptible water suP?ly commit.ments in excess of basic 29?Ortionments. :ioweve~ I t,.;hen these aggcegat~ consum?tive uses o:each these levels, commitments for an uninterruptible delivery of water ie) excess of basic apportionments could be less likely depending on available reservoir storage. At that time, an additional ~ater: use commitment, if 2??ro?ciate, could be more limit-eeL In cases ~her~ the 3ureau of Reclamation's 24-month operational studies indicate that flood control releases in excess of do~nstre~m water needs would occur uncer a most orobable water s1..!oolv condition, decisions relative to cO:i\mi~r.lents for u~lnt.erruotible increasea .....ate: 1..!se are fairlv st:aishtfo=~ard. Decisions for r~distri~ution of antici?atec ~xcess ~ater are ap?ro~riatel~ eval1..!a~ec under various 24-;l:on::.;, .....atet supply scenarios with scheduled r~dist:ibutior. of :eleases made for only the o?erating plan year, sUDJect to ~o:1th-to-month changes basec on cctual hycrolog ic co~dicions. .~.bsent flood control releases within t;,e next 2~-month peric~ with a mos~ ?~obable ~ater supply, decisio~s based on 24-mor.::.h evaluations under "nor~al" cor:ditions for the oDeration of ;:'ake ~\ead are less aDDarent. Given the current level of consumptive '-'iater: use and reservoir conditions, it ~ould ta~e t~o to th:ee years of average runoff Eor the syste:i\ to rea::h full reservoir conditions following t....o 0:- th:ee years of significantly ~elo'''' ave:-age runoff.. Conseauentlv, a 2-vear (24-month) ooerational studv mav not provide the-necessary foresight needed for the deveiop~e~t of an annual o?e:ating plcn. The need for a 5-yea: analysis, in acditio~ to the 2~-mOilth ooerational studies, i.~ ma:":inc "-'atec availabilic.y decisions 'Was. idenc.ifiec and p:oviced for- in the craf::. fece:al/state '"Jerking document on the reco~;;jended process Eor dev~loping annual o?erating plans Eor the -3-