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<br />G LOS5A 'ty OF T[":.~S
<br />
<br />8e~ri no
<br />
<br />TMll ~or; "ontJ I ,'ngu lar ""'~5urt""'~n. of ~ line, in dcqr(,,,s,
<br />c:>st cr west of ~ ncrth-~outh reference linG.
<br />
<br />Flood Prot i Ie
<br />
<br />Flood
<br />
<br />A gr:>ph s~cw i ng the re I~tion~h ip o' w~ter surface () I..va-
<br />tlon to loc"tlon, the latter genera Ilv ex~res~ed a5 di st,H'(;(> dJove ""\Cu~h
<br />for ~ stre~m of '.;ater f ION i nq in nn open channol. It is q,)11orilllv c'r.'>,' n
<br />to ~hON surfJCO elevlItlon lor rhe crGst of a sneci f i~ f I oed , bLJ~ ,..,,,
<br />be nrcn"red lor cond Itions at 11 q ;vell tiCle or sta~e.
<br />
<br />An ovnrllo.' on l:>ndswJfnorr""llycov<lredbY'"aterand
<br />thJt Jre used or usable by '''In. Flo:)(h have two egsentidl ChdraCh,ri',;tlcs:
<br />The i nuncat ion ot I MId is temporary; and the land i s adj~cent to ~nd i n~n-
<br />datad by overt low fr()"ll a river or strc~'l or In oce;,n, lake 0, other !lO<!y
<br />oISTanding"'dter.
<br />Normally a tlood i5 considered ~s any temporary rise In
<br />stream flow or staqe, I>ut nor the p0ndin'l of surfaco'Nater,tnatr esults
<br />in siqniticant adverse effects in the vicinity. Adverse eflects mJY
<br />inclucedanugesfromoverflowot lanaareas,tempor"ryt<ackwllterelle<;ts
<br />in scw",r~ and IOCJI ~rJ;M~e chdnnels, creation 01 un5<lnitElry conditions
<br />or other untavorabl~ situations by deposition ot "",terials in stream channols
<br />durin~ t lood recessions, use of ~rou""d water coincident with illCre~sed
<br />stn!il,n tlow, and oth~r problems.
<br />
<br />Flood StJ~e
<br />
<br />The ~tJge or eleV.1tion at '~h iCh ove,f ION "f the natu,ed
<br />,~anks of ~ stream Or body ot '''ater bO<1I n5 I n the reaoh or area in whiCh
<br />thCl e IClviltlon i s rne~SLJroo.
<br />
<br />Head Loss
<br />
<br />The effect 01 cb5trLJctlon~, ~ueh a~ nar,cw bridGc o"cni~~s
<br />or b u i I dings that I im i t the J,01J throogh w h I ch water "'u~t f 101, ra 1 sing
<br />tho surtace of rhe water up~tream frcm the ct>struction.
<br />
<br />Flood Cr...st
<br />
<br />.!.:!.ter".ed I at".J~,,-~.U~~...!.. y_~)_r.:?_
<br />
<br />I; Ilood h~v i "1 " "ne p<,rcent prcboo i Ifty of OCCurreOC"
<br />h ,jny yeilr or an aver"ge frO<1llencv 01 Q<:;curn,,"'CA in the onl<;r ot o~c'"
<br />i~ 100 yea~s. The fiCO<! rn~v occur i~ ..r\, '1'lar. it is DJ'led 0~ st~ristl-
<br />ell I dral'lSls ot stream II"" records ~nd <)I\,llvse~ ot rJlnt~11 ~nd r~notl
<br />cll~r3cteri~tjc~ In th" goner"l ~"gi(}n of th" ",~torsh"rl.
<br />
<br />The "'ax,i",,,,,, ,to"e or ei>>vilt ion r,,~chec by the wJtcrs of a
<br />f I()od al a "ive" loc~t ;()n.
<br />
<br />r I"od PI~ In
<br />
<br />Tno reiatively t IJt are,) or low I~"ds arljoinin~ he chdnn>>1
<br />ot J river, stre"", or ,,,,~ter Cou~5e 01" =''.'In, I"~,, or oth<;lr Ix'~y of stan,i~'l
<br />..."ter, '"Ilich h<15 hf)"n or "'-3'1 be Covere~ ~v f load w~ter.
<br />
<br />LettGank
<br />
<br />Course,
<br />
<br />The b"nk on the left side of a ~jv(lr, 5tr(l~C1 or w"I"r
<br />lookingdo.;nstre",..,.
<br />
<br />i\otenH\cQPoint
<br />
<br />"
<br />
<br />,~ nurrt>€'red ~c i nt i(.ent I f v i ng iI sp€'C i f i (; locat ion for
<br />c(.r~olcltlnq the> data 'sho; n In variO"~ forme, t~rQu~hout t'1e r"re>,+.
<br />
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