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FU'rURSFLoors This sectio~ of t~e ~eport Qiscusses the rnt~rme~iatc Region",- rloo<o, St"NJIl."d project FlGoC, And e",rne 0' th" haza"d8 of noods. the InterMedi~te Regio~al flood for averaged ma~i~um conditic~~ withi~ the study ~rea are shown on T"ble 4. Severe as t~e rnaxi~um k~o.T. flood ~y ~ave been en a 5trea~, it is generally accepted t~at a larger flood will occur. Only .in rare .inst""c~~ r."" d. 5tredItl experh",~,,<1 the liirgest "100(1 that is possible. Larger floods hav" beer. e~p"ri"~ce(l or. stre~~.s with simil~r geographical ~~d p~ysiographical Characteristics as those streams ir. the st'-l.dyarea. Severestormsundo1.'btedly'"ill recur i~ tte F01.'~t~i~ C~eek watershe1 to e~use future floocis that can equal or surpass kr.ow~ historic floods. rn any d"terfdn"tio~ of future floods that may occur, it is desirable to consider all stortr.s ~nd floods ttat have occurred i~ the reg Lon o~ similar water- sheds. 'rhe Corps of Engineers, in cocperatio~ with the ~OAA Weather Service, has made c~prehe~sive studies and investigation. based on vast records of experie~ced storms a~d floods an~ has evolved g~~erali~~~ procedures for estimati~g the floo~ pote~tial of water- ways. Standard prolect Flood The 5tandard Proj.x:tFlooct is defined as the flood that may be expected from the megt seVere combination of meteorological and hyd"ological co~ditions that is considered reasonably characteristic of the geographical area in which the drainage basin is located, e~cluding e~tremely rare cornbi~atio~s. The Standard project Flood was developed through the use of the June 1921 storm. The stor~ wag tra~sposed to critical posi- tions above Manitou Springs and Colorado Springs. It was adjusted for location "ne a relationship developed for drainage areas and discharge to compute the peak discharges for the streams. Charac~ teristics of the Standard Project Flood fo" averaged maximum condi- tions within the study area are shown on Table 4. Intermediate Regional Flood 'r~e Intermediate Regicn~l r~ood i~ gcn~~~~ly reprcsc~t- ativ~ of floods Chat ha~e occurred in the pas~ and may b~ e~Dected to reCur in the future. It represenc~ " major flood. although it is less severe than the Standard Project ,1ooC. Tee ",,-,g~it'~dp. of th" I~t~m~diat<' %qio~al Flood ()~ Fou~tain Creek a~d Tributaries w~s ~<,tcrF;n~2 from ~tatistical analysiS of regto~al annua: peak flew records. Al~o, tte variable rdi~fall dr," ru~off ~har"1.'terLs,,-ics of "'ater"he~.5 ir. th.. region ".ere cO'"'?dred, adjust",l wh<,n necess,lry, ""d '~"ed for the analysis. l-".axirr,u", kno~"f', floods ttat :"lav., ="1.'rr"d witl'1in lote r;eo~ "r"F.hic~l rccio~ 'u~ list.cd ir. Table 3. Flcod cl'dract,'dsti.c~ cf Frequency of Floods The I~te~.ediate Regional flood is defined as having an average frequency of occurrence of once in 100 years at a desig- nated location. It is impractical to acsign a frequency Co the g~eater Standard ~~oject Flood. Floods larger than the S~nd~rd Project Flood are po~sible, but the combination of factors necessary to produce such large flows would rarely occur. For purposes of hazard evaluation, it is importa~C to recognize that either of theso floods can occur in a~y year and po~sibly in successive years. n "