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<br />In general, rain gages provide quicker tdenttfication of flash <br />floods th,~n stream gages. Strealll gages provide a more definite "arning <br />a~ th"y r"""rJ flo"" ,..': uaUy in the river. For ratn gages, dat~ <br />tnterpretatlon1ll<lybeOloredifficult,astherelaUonahipbet<Naenrain <br />and re~ultll.n~ runoff needs t<.> be esrabltshed. Stre<lm gages may "ot <br />provide enoullh lead time. If the gages are .paced fer enough upstream <br />ro prOvide s<.lfficient lead time, rlltnfall do",nstrealll from the gage <br />could cause higher flooding thane"pected. FortheaUern"Uvesin <br />thtA report, there are larger number. of nin gages than stream gllges, <br />.0 the loss of a rain gllge WOuld seem le~s serious than the lo.s of a <br /> <br />Early detect ton inalter"ative 5C<Nould be depeadent on the <br />reliability of the volunteer rain gage network, liS h true of <br />alternative 4. The ..utoTI<~tic stream gages WOuld ser off a more <br /><lefinite flood alarTllaa floodinge"tered the OlIljor streams. Visl1ai <br />verifi"-<ltionofstreamflo"'scouldco"",fromsomcrainob.ervers, <br />alrhough "'ithout staff gages, they "'ould have no specHic stream levels <br />to report. <br /> <br />stream gage. <br /> <br />Aiternstive SD, with only ~tream gages, would not provide <br />~ufficient lead tIlll<! for areas cloae to rain storlOs. If N'"g .radll.r is <br />operating, SD could not provide confirmAtion of rainfall intenslti~s. <br /> <br />The reliability of all th~ fla.h flood detectIon aiternattves is <br />dependent on radio. It is pres"rued that for each altern"Uv~, l.atimer <br />County's planned radio network cO<.lld provide an alternattve radio <br />tranamisston route. If not, the entire alU.rnattve might b<! rend~red <br />inoperative ifasiagle repeater stll.t10n <Mlfu""tionedbecause of wi nd <br />daug,,", vandalism, lightning, or or her factors. <br /> <br />Alternattve SE wo"ld provide early warntng ",ith lIutomatic rain <br />gages serving the m.ain stem<lnd automatic streamgagea onthcNorth <br />Fork. Ihere is the possibility that, in practi~e, local offICial. <br />might heaitate to Ias<.l" a warning based on ratnfall and "'ould ",ait for <br />confirution by a Stream gage. <br /> <br />designed network if rhere ",ere absences Or a 11l.c~ of readiness. <br />areaS sre popularedtoo sparsely to add substHuteobserv,,-rs. <br /> <br />Many <br />;.Tith <br /> <br />Alternatlve 6, with a completely lIutom.atic network, "'ould not .pro- <br />vide a backup means of flood detection. There "'o<.lld be no c<lpabilHy <br />for vtsual vertfication of flooding or for <ls"lstance In warning <br />diu~dnation. <br /> <br />'1mMAA' <br /> <br />The =lunteer network In altern</.ttv.> ~ <Nould have gapa in the <br /> <br />Inadequate reports, th" network I!l.iy not be able to lndicate IOor... than <br />"he<l.vy rain". In that C<lse, a lo"'er COSt, leas fot!Ml volunteer <br />net"'ork "'ould serve as "'ell. <br /> <br />AsaulOing the absence of external assistance from the X~'S or a <br />spotternet",ork, alternative SE ts tentatively reco_ended. It\Oould <br />provide the earllMt "'arnlng of a reasonably definite Mrure. AI:er:'l"- <br />tive 5E also "'~11d provIde visual veriftcation of flooding and ~ method <br />tn ~Id ~~~~ing di~~~~l~tto~. <br /> <br />.'l.l~e:r"atl"c 5.\ '"ould ~e de~end""t "n th" r..~dt"..~" "f ""l"n'~e:r" <br />along the main stream. Ihe r~o separate networks, automatie and <br />volu"teer, "'ould serve dlff erent geoSr~phic Are,," and "0 "'ould no~ <br />provid"redundllncy. <br /> <br />If a reHable rai:'lfall spotter net",ork c1\n be tlDplemellted ~<l <br />provid~ early alerts, alternative 5D "'ould provid~ very credible <br />verlfic.ationoffloodtng. <br /> <br />'0; <br /> <br />IO~ <br />