|
i;oca Sludges
<br />•
<br />l J
<br />•
<br />5~, ti /Jelhod of Computing an Inflow Design
<br />Fm: d.-The follott•ing procedure is based to a
<br />+; : _~ rs:e::: o° tha; ttcen in the Seil Conser•:a-
<br />tio~: Se:~•r:ce's "H~'dro;oe~' G::ide for lisz in
<br />l~:,tcrahed Piannil;~." tree bib:io~raph~', sec.
<br />~,~~1• ,r.lf \ .... modiP,ctalons ;o n-.ert the p;u}~e=e
<br />, . ,...> text ; he resulr,u~ ir.:l.,\•: (icsi~n flood
<br />t,:okra),!: rol~ra;cat~ ducet nnlo" from pre-
<br />... ...... ..::1 thr turn of r: in ~nrr a v:ata'shcd
<br />,..... no Lulu.ual runolT chnractcr:;tiax. If
<br />,: r(v 1::::::.... ,:at u! "o\c i~ c>:pcctcd to Lc In the
<br />:I:anncl a: th^ time an in9u\\ do<i;:n P~oo(J co(.ld
<br />~u'Cn1', the :.:::OG^: Of th!s ba:2 fu\c should lie
<br />a(!dr:i :o :hc iaPov: desl;-r. flood h;:dropraph.
<br />Ti.c ;;ru:cc::rc outlined assumes an un~ai'ed
<br />~1, ::. Cnm;n,tations fm' a ~aeec area v: ill di(Tcr
<br />ir. :'r,..t cat, rc~ardnl~ unit~raph ch:n;tc-
<br />..a:c~ :+::,! rctcnumt to>scs oi>;alncd from
<br />:. 1:..!•: ~•:: (•` ra~cnnic•(! runo' shnul(i Le used.
<br />1:!1 ll'nr,r.urr/ Dntr..-The tolloc:ir.o tt'a-
<br />' .'-a^:: C::;a ;I I'(' alts: a\': ll i•C(!C(::
<br />111 Geo;:r:.phira! locaao^.
<br />•"~ .l",; ;, .;;o..::..:' topo;:ran:^.;:, arear..s. and
<br />.. . _, .al':o\t desi~r. foot! :'enuired is that
<br />:. :_, :: ~:::c:s a m,rr:oi: full to :op of con-
<br />rc:~•:a;lun .:oray;i•: therefore. ;hc propo<cd
<br />rc•t~rw:r surf::ce contour for :his eleca-
<br />::U:1 Ir•ul'ma! R'al Cl' Sl1 I'~aC'C) 5hOll1G DC
<br />... ,.`:. Il ~.^ ;..^.C Cia},. 1hC ~:'OpOSCd re5er-
<br />','J:I' \'::I! h.^. \'C' a!t 1nH CCai C, 50mclimC;
<br />~;::itr :. ~c, wl :hc comps:aeon of \c:rter-
<br />sh:•,'. Lecausr in9ov: into a rescrcoir
<br />!! ,r.nrr~c :hc rescr\'oir len~t'n n:urh
<br />t••urc . ^.pidl;' tbnn alor.~ a similar Icnbth
<br />~,i r.:utu;a >u'c:tm citar.nil. P,c<crcoir•
<br />Ir::~:r: a:~cr! time is nn; inc'.uced il: T..
<br />i:, ..:: n.ir ;nllucncr tin :::c::<uremcr,[s o!
<br />;C~r.:nt .- xt:•`. or T, c•snm:ltc= arc shout r.
<br />fir.:;~l:±(.:!!~' on flrtn'e 31.
<br />'::1 I:~`~,: -::::lo!t abou! soil> sod ~•e~ ctaticc
<br />ant their (1:;triL:l;ior. :hrouphou: the
<br />il,l li,nr, .~, ,., ~ ry., i': ..-I: hyc bL'en I,OIIIl-
<br />'' ... ,:1 ~•rtuvl .', th;lt an ..l"oc ll,~t~d rt: not
<br />...~•., ~,• ,~,1:::\~:~Irn: to t`lc n....:mlm: pr(~1~::!-!e
<br />. ...,I lit tL~~-c nl<;;uucs o:hcrc 1: is In•rmt>-
<br />''~" 1~~ ~It'~I:'ll to:' IC~> :..::n 1.^.C .T.a Slmam prOb-
<br />~'.' li~•"~!. a rca<onablc reduction In the seccr-
<br />73
<br />it}• o` the factors a`rec:ine flood potential car.
<br />be made. In this text, conditions dz=i~r.a:ed
<br />as assur..ption .y and asst^p::o^ E, to be u.,zd
<br />t': hen con_icerSne dzsihr• f:ooc< ;e_s than the
<br />maxirl::a: probable. are gi\en ;o pro•:idc a
<br />method for ach;ecct~ a co:ais:er.t de>'rce of
<br />marr.lu,de as nzlatzd to the ri=_}: o: dama~r
<br />o.hich tto:lld rc;ua trot.:>u'uctt:rcfailure.
<br />Llrs:l•n storm nla~nl:udr h:+s Lca:: a.!cctcd a<
<br />basis for com,tu:m,; ul"o\•: des:6n ^ood- for as-
<br />sumptinr.; .a and A. Section ;,0 presents data
<br />for ch::u.^.:r.;r probable maslt~::n: preeip~:a;:ca.
<br />cnlues east and ties: c; the 10~` meridian and
<br />char, indlcatin~ reduction factor< to Le ::p-
<br />phed to proLabL max:mu:n preclp~t:~uon cal-
<br />ucs to obtain dc_i>;^ storm ealuc> for loo:
<br />hazard areas. I'recipi;ation calves computed
<br />br direct applicatio^ of the reduc:irr, factor<.
<br />figures °_°_, _3, and °_~, are applicab:~, a; de~ic^
<br />storm c:~lucs for rnmputi::;• .^.:'.ov: de::•_:'.
<br />floods for a.<>um.p:ion P, io:•: h::=a: c ::r.::>. u`-
<br />ir.,, the . _..:c . _trn:ioa los;cs ... °.~~~::calur ,r
<br />., maximum prubaL:c ,":ood. .-~--•.:^•,::rya .~
<br />pro\idc•, cnteri;: for ;n]'.0'.t' ^es._n °nnd: for
<br />strut:w'zx vrhere failure could not it:cre•ae
<br />danpcr to human lift and ;omc ri.k e.r Llilure
<br />r.:ay be :ol(:r:aed. Des~n storm •:aiur.; for as-
<br />sumpuw: .-1 :tic ob:ainzd b;' ::cer.:_:r.,• dosi•,n
<br />storm ea!ues app!ic::ble for maximum proLai,le
<br />flood an(! IOI' aa5ll T,p;:O!1 E °OGd cU C:;II:;::'.IUL'<.
<br />reter.uor. lo» crnr.'::: :,rc the .,..n:c :~.; for a
<br />maximum proLab~c Hood.
<br />The fo!!o•.cin~ criteria for design ..°,oods :tic
<br />thus cs:aL!:shed:
<br />!r Tl,r„
<br />(;) F:ulure o: structure 111 L,Hut, ,ies:en flood la
<br />ta'nw,: ra•sult In DroL- e,iun ., I,~n'. to iLo m:u~
<br />nhlr Inss of hu r.:nn hfc. iroum Drobab:a O~wd.
<br />(^) Fn~!urr trould roust ('!1 In.`lu„ ,.,~~irn flu,.J
<br />c rt•a: d.. m:, cr tc Dro P. may Lr :,, n:urh Its.
<br />rr:}' anJ prolcct eP. lhan thr :n:~timum
<br />cratio n. Lul loos n! pr.,l,;,l,:,~ ,,, that ..L.
<br />hum:u: Lfr ~~. no; rn. t.wn~,! i.o .,-.,nn pt ran
<br />v to wood .\.
<br />(31 F'.a!u re would cause IJI lnl :,, a~ a.~•i;;n flu,"1
<br />aril; Ies, o; s[ruetcn. wn> i... .,, incrF. I,~„
<br />tai:h Lttir ad,iia~n.,: tF..u, :hr u:.,>imum
<br />Jamac(• In Dru Pr rt )' pn~L.,ld, a. :I:al nL-
<br />llnd DrUfCr: ODCrJtIUn. tJlnr,l I, t' :U'UIII)~I fun
<br /> t:.
<br />r-
<br />
|