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<br />da""~es to recteHtcnill val""s "~,,I.i "^ .tini,,,,,t. .,.~~ ~ " ", ','
<br />O'C "'~ "~,,e cl. .,.Co" o. "e
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<br />k<lCp the to<1d cleared of debris durin;; th" rnudf1o\O's. In 1972, an automobile
<br />IdS shoved off the high''''y by debris And totally damaged. Fortunately,
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<br />lOO-y""t flood is sh~"" ()~ th.~ Flood Haz~rd "rea hde)[ M"~. Deta1t~d
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<br />outHn,," .ho'..i<>g t:h.e "',"rr()d'nat~ lLnlt:< of 100- and 'jOO-y"a" fload~ are
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<br />located 0" the i'lood H~?3ru .\re" I-hps, s"~ets 1 throllgh 10.
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<br />there wer" <10 8e.io\ls inJ\ldeR In that event. Mudflows 1<1 1965 and 1972
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<br />ca'.., dose ~o SOme of the ",~blnB located nc,~( the high"';;!)'.
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<br />ObHrUttllln.r. in [h" fLooJ pl.,l~, "-Hue..! ot '""n-rIl<ld... tnfluencc the depth
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<br />"t1d "'[dth of the "rea flooded. Tee".. and br<.1sh ~ro"lng al<>"l\ tile
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<br />Fl.OOU PO'f~NnAL - ~RESeN'r CONlJ(TIlJNS
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<br />.nt""",b'ln:';s r..tard th.. ('ut of channel flood flo",s cau,.1n8 b<lc:';wat..r .,nd
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<br />g,eater depths of floodin3. R.o<ld cros"lnl;~ wlt!1 inade'lu,~te culvert and/or
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<br />H<I~ards of Lar~e Floods
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<br />bridge openings often hocome channel constrlctlon" and obstrllctllln to flood
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<br />Amount of dmn..g~s ..nd hazardous conditions caused by <lny flood are dependent
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<br />flows. ELevated roa,i~ Ln th~ flood pbLn "ct as barriers whleh r"ise the
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<br />upon' d~vclopmenU in the flood plain, topography of the flooded <lrea,
<br />ohstructions and debris, d"pths and ""locities of flow, and rates of ri$<.'
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<br />water surhec <It ''''1:1" Lo"ations. The effects of clltvert ~nd bridge
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<br />constrictions are graphically d1splay<>d on th~ Hood profile drawings,
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<br />andd<l<at1on of flooding.
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<br />E~hibits A-lb, A-5a. ..nd J\-6c. Tre..s, brush, and debris ",ashed out du<1ng
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<br />the period" of h1p;h runoH, are carded downstr<>"", intu b<idil"S and
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<br />in respect to the total flood plain, the largest ,~rea subject to fl<)oding is
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<br />c\llven.. Th"~e "b~tr"crt<)ns act ," 1am". backing th" water upstream, until
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<br />used for agrLculttlrlll ,~lld ,ec<eatton(ll purposes. Under pr~sent conditIons.
<br />potential floods of tll" H)OL al\d 'jOO-ye"r freq"ency would inundate Aome
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<br />they break loose. C'lusin;, .'1 sud,l~n g'lrgc or '~"ll "f watc< "tth addtti"n"l
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<br />d~5truct i ~e fon,'. Obst ruct 1on~ call"cd by dehr l" ci(}g~lng cu Iverts ,mol
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<br />horoeSit"slnreach.Nos4"n<.l6.
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<br />Tenaxistlngb\ll1dings, includIng
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<br />bridge" a<e v.~rlabl<>, resulting In " ,"<iLtl~u<.le <)f H,,,,, con,liti(1M ",hl,'1,
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<br />res1dentiat and utilLty st<uet~res, are partIally or totally located in th..
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<br />unpredictable for "ny given flood eV~nt. Ekr.ause of tl,.. rmuy variabl"" 1n
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<br />lOO-year flood plain. noodw'ltcts fNmChalk Cteek eould Cause d"""'ges to
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<br />flow conditions, th~ pot""tlal effcc~ of debris clog31ng .ua n<>t inch,d..d In
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<br />huilding.., lawns, gardens, and r,^~d c~os$ings. Most of the agricultural
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<br />th"fLoodprof1Ie<ietermLnatlon".
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<br />"rea Is in pastu<e and hayLand (read, 2 and 3); a"d flood tosses "O<lid
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<br />Include '\;"""ge.. to lrr:lgnU<>n syst~ms .,nd depo":ltlon of .~~dtm"nt and debr18.
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<br />~tood "'ate, flowtng at hlilh v..loclt("B ~r""',,~ rl"ng"''''''' condttiO",s. lJel,-
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<br />Fo<tunatdy. much of th~ flood phln is stltt Ln Us natl1r"l condition and
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<br />dti,," "xce..rllng 'J fc<'t I"" sf'c<>nd ..lth <1cpth" of 2 feet or ''lore ~'e
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<br />generally CQnslderd ll:,?'..'rd,,~s. Those co"dl~ Ion" wo"ld e><i"t a~ v"lri<>uB
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<br />IThe lOG-year ftoQd ts d flood hadng .1<, average fre~llency of OCCllrrence
<br />or "n"" ill l '.1'.1 y.."rs. It b,.... ., I [)"r"."'~ chan~.. uf hf'lng ~q "" 1 led cor
<br />e~c<>ed~d l:l .,ay gi~~" yellr.
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<br />10c.Hio~. {n the Hu~y ,He", "sp..~{al~y in the str~,.." ~hdnnd of Ckllk
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<br />Cr....'k, 'Io~' of ",e nnod rl3tr. O\l~" ld.. of the ~:re.."" cIHnn,,] Is "ul>j"c~ to
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<br />"hallu", fl<>"dl ng "ad th~ fto",_, are t"s~ th"" 2 f"..~ in d.,pth.
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