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84 DESIGN O; ShSAI.t
<br />Example s-F1ooJ Leas Then tht 1Jnziu,um prDLa L(t Eost of (ht Jn5' .1(e rir/lurr.4 a.u rn pfvml (l
<br />•
<br />i
<br />•~
<br />1
<br />1
<br />Crnrul prprcJUre
<br />1. Thy rnm putatln na; procedu rr is the came nc prcei„uclp uu;h nrd In ez~n+ldr '!. Uri:::n ,I•~n:: calu~•~ :~n
<br />rr:,,IrcJ r:un(a I: : n-.cu r.[s nLtaincd Gy' csur,; the n•J urtmn L+c tur fur I;rut; r;lphlr:~t L,ru:n'n :::+-~n un :1,;w
<br />1 a.t ~:cp L ct amp:e ^1. U+rrcl rune.^. Is rompu:rd :+csuml:~;~ sox mJls:arc of ll:e v: a:rr>'.r ., Lc("re tLr di
<br />storm bcy;:ns. to Lr re, resented by antarJ. nt mocWre cunJiUOn 11 I.1VGilr C\' GL lo-r: >t r, :. rz:ull pt~
<br />^_. C~,alpu:~tlun o' direct runJR and plo:un,° d~tc car. Lc romhmrd into unc eaSulaGun as follou~>:
<br />~,~.,..
<br />r{,..ur ~ I..rr..
<br />~ e n.
<br />mrl~n' ,.r„m,l-
<br />1 n.
<br />nrl.n' I
<br />I n~n,.rt.,orl...
<br />
<br />area n..,, In.
<br />•, r..
<br />lau`a ' „I.I
<br />a
<br />U-I I 0; 0.r 00
<br />u0 I
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<br />:-~+ ~ 49 7.J U.:: 1 U.:U
<br />
<br />+-'.
<br />.... ~ 1.J ; 5 7.50 0.93
<br />:r~.
<br />~ ~~ , n; e.l ~ JlA ~ o.lo
<br />+:-IJ I 1.6
<br />I 98 Jd0 0JO
<br />1:~1i LI 10.9 I I !
<br />~ rrom rtrD 1 Of rvmD~e 3.
<br />+Frcm. Oaure MJ Ir; Dre_:. Ai for Curve \"umGrr 6:.
<br />' r.r V :J men per IIOYr C\ IS Prb 9.1a Inc A,
<br />lum vn lm
<br />ul 1 1 u
<br />n^.n• nr 1,
<br />i urn al
<br />I .•r1dr
<br />O7 I
<br />Of.S ! !9W
<br />0 ~ 0 I !; •(q
<br />1 OI ;yw
<br />0.18 5JW
<br />`.:0 lrtq
<br />L:V ].'JJO
<br />ae Ln
<br />•'d ~ '1.
<br />I~ I '.
<br />U u
<br />I:U I I
<br />LtiW -
<br />1].9:U 7
<br />ills J
<br />Y. ~:4
<br />I :,W I ~.
<br />n
<br />U
<br />IU
<br />I1 :•
<br />3. T:ne plcttcd hyd roCnph is shown as ~gurc 3;.
<br />The rv noR hpdroCr^-n for G.0"_anch ezcese, hoer _, is so sn:~li m cumpa rlson urth U:h~•r calu'~z tnnt It m~•,:..
<br />plu;ted.
<br />tdl Cuulputctic,l n! /rltiotc Design Floods-
<br />I1'rst or tht (u.;- 1leridinn.-Es;reme dicersi:•:
<br />o.` terrain and precipitation characteristics
<br />ttc;t:•:ard from the IuS= meridian to the Paciilc
<br />Coro: make doubtiu! the application of a sim-
<br />ple Genera! procedure for computinG in~ott• de-
<br />siGn floods for the entire region. Therefore,
<br />ttto types of de;iGr. precipitation hate bier. da-
<br />ccio,cd for thu test: (I) probable mastmum
<br />General storm (P\?C,S), and (°_) probab:e mas-
<br />imum thunderstorm (Y~ITS). Potential rain-
<br />faL' for each type of storm has been ecineated
<br />f`or three dilieren; zones: P.l?GS for Zones
<br />Jl, B, and C (see tiG. 1 ~) ; P\?TS for Zones I,
<br />t[, and III (see P.G. '_0). An aces along the
<br />~'`-rst Coast }::a been delineated tchere poten-
<br />ti:a thunderstorm rainfall is not corsldercd
<br />crdca! for ir.3o•.c desiGn flood computation.;
<br />(,ee nG. '?V). Titr charts, t:Gures 1. and 20,
<br />present Hsu}:}r;aL of c;;:mated probable mas-
<br />ir..um point rainf:;:I, from v:hich a tots) design
<br />storm for respective t}-pe rainfall may be de-
<br />celoned b>' use o' ..?prupriatr anal rr,iuc
<br />cur ccs, rainfa!! time-disc ribatiun curt c•<.
<br />table.=, tchich express rainisl'. a.r~o:nus i:n
<br />ious time inters;as as ratio. to point r.:i::
<br />FiGures ~3 snd °a h: cr b'.•c^ prc!~;Ir_r
<br />proride es[imates of reduced stca-n: ;1"t_:,
<br />for computinG Hoods lea< than probahlr n.
<br />imam for lout hazard nraas tees[ of the ''
<br />meridian. Design storm data and the Grit
<br />for determinir.G desigr. S.orm value; fcr
<br />sumption J1 and B flu'.ds thus pruti~!r t
<br />cipita[iun amount: fn~rn trhirh sit i t!
<br />drsii;n Iluuds ntac be cuminnrJ f"r c
<br />tcau•rzhed studied to i:in rc~iuns scL
<br />[o [hunddrsturm rai:~!al;. Ilulrccrr• it t,+
<br />6e a rare circum:;;lnrr that tvuuld rr t
<br />computati~ln of a!1 >i~ d'~~n! tcrt•<
<br />a Oa rt ICU!af t1;t7n.9:1c'. ~!!r iuCa!1"11
<br />imlicatr tchctht•r c+Ir.:IJrra:l'ut ' , ;;r
<br />Iran [Fan plvi,aLlr n:;l~l:num ix -:nn:''
<br />ate. G: :u n:. a;r area sicr. fi,l nl6lte• lure l„n.
<br />proposed resert'ulr stur;IGc trill ust:al!t
<br />In .. u,.N+l In •In.. r ,~ i
<br />1'.. I.
<br />
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