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!"'-'1'~PE "<.OODS This s=tion of the :rep"r~ disc,-,ss",,, th~ In~er"'e"-iate Reqio~"l Flood, S~,,~d":rd Project flood, "r,~ "orne of t,,<> b,,",,~d~ of f1ood~ . the rnte~mediate Regior.al Flood for aVerag~ maxim~ co~dition~ within the study area are shown on Table 4. Scvo~e ~s tbc r~xi~um k"o~~ flood ~,y have bec~ G~ a st:rea~, it i. generally accepted that a l~~qer flood will oc~ur. Dr.ly in tare insta~ccs ~~n a stream e~petienced t~e la~gest flood that is possible. Larger flooCs have bee~ e:<p"ri"mc~d on ~tre,iI'"n wit~ sL~ilur qeoqr~ptical und physiographical charac~eri~ties as those strcatn~ in th~ st:.>dy area. Severe stor",s undo'~btedly will recur in the Fountain Creek watershed to C~uSe future floods th~~ can equal or surpass known ~,istoric floods. Ir. IWY ceterminatio:'l of future floods that may occur, it is desirable to consider all storms and floods that !\a\lO) occurroo in tr.e r~gion on similar water- shoos. T~e Corps of Engin<iers, in coop<<ration with the NQj">A ~'eather Service, has made co"prehensive studies and inve5tigations based o~ vast records of e~perie~ced s~orms and floo~s and has evolv~ g~neralized proc,",lur~3 for esti""ting the flood po~~ntial of water- ways. Standard proiect Flood The Standard project Flood is defined as t~e flood that may be e~pO)cted from the most severe Combination of meteorological and hydrological conditions that is considered reasonably characteristic of the geographical area in whiCh the drainage basin is located, excluding e~tremely rare combinations. The Standard Project Flood was develop~ through the use of the June 1921 storm, The storm waS transposed to critical posi- tions abQve Manitou Springs and Colorado Springs. It was adjusted for location and a relationship developed for drainage areas and discharge to compute the peak discharges for the streams. Charac. teristics of the Standard Project Flood for averaged maximum condi- tions within the study area are shown o~ Table 4. Intermediate ~egional FlOOd ~he rntermediate Regional Flooe is generally reprcsent- ative of floG<ls that hav" occurr"d in the past and."ay be expecte d to ..ecur in t~e future. It repres<mt,o a majot flood, although it is l~s' sev"re tr.an th.. Standard Proj",,,t ,'1000. The ~~gnitude of the Intermediate Regional Flood on Fountai~ Creek and Tributaries was determined from statistical analysis of regional annual peak flow records, ~lso, the variable Frequency of Floods The Intermediate Regio~al Flood is defined as having an average frequency of ocCurre~ce of once in 100 years at a dcsig- Mt~ location. It is impractical tc assign a frequency to the greater Standard Project Flood. Floodc larger than the Standard Project Flood are possible, but the combination of factors necessary to produce such large flows would rarely occur. for purposes of hazard evaluation, it is important to recognize that eit~er of these floods can occur in any year and possibly in successive years. rainfall "nd runof!' c~aracceri.stics o~ w"t"rohcus in the reqi.u" were compar"d, adju~t"d "'''er. nec~3.3"ry, ",,[1 '.'"P~ fo,.. the analyst", Maximum ~no~~ flood$ that have occurr"d ~ithin the gcc- 9'rap~.ica~ r",;io~. are listt:d in '::"h1e 1. Flood char""t"ri~tics of " "