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suCh a flood, but their ~agnltude can be ~pproximated by the floods that occurred on sever~1 streams In the Denver ~rea In 1965. The peak discharge for the Standard Project Flood on 8enr Creak 10 the study reach would be 76,500c.f.s. Floods s_ller thao the Intermediate Regional Flood are much more COIT'iI'lOIl, as evidenced by peak discharges of hlstoric~ I f loads in Table I, but can cause darrl<lge and hardships. FlOOds larger than tho Shnd"rd Projoct FlOOd "re possIble, but the combInation of factors to produce such floods would be extremely rare. hble 2 INTERMEDIATE REGIONAL FLOOD DISCHARG€S BEAR CREEK Location Upstream Ilmlt of study reach KlpllogStreet W"dsworth Avenue Wast Hampden Mouth ....eak Discharge c.f.s. 30,000 27,000 25,000 22,500 19,500 H<:lzardsofLargeFloods The areas flooded by the Intermo'diate RAglonAI and StAndard Project Floods are shown on plates 2, 3and4. Profllesan<:lcrosssectlons, on plates 5 through 10, Show flood depths In relation to channel features and ground lovels On the flood plaTn. Roferenco points are shown on these drawings to correlate them with data presented !~ table J. The data In table:; Tncludes distance from the mouth, streambed elavatlon, and the water surface elevations for the Intermediate Reg!onal and Standard PrOjeCT flOOdS. 1he ttOOd OUTlines were produced by projecting tM computed waTer surface elevations onto u. s. Geolooi~al Survey quadrangle Il'I<lpS and surveyed cross sections. The outlines are reasonllble rather than precise. ~.here IICcuracy is needed. It will be necessary to take the appropriate f loed elevation from the ref"ren~e tllble or profiles and fln~ by survey the corresponding location on the f loo~ p laTn. , I Bear Creek Is crossed by 7 hlghwllY and street bridges. The profiles and reference hole show thlltthe br"ldge crossings sometimes cre"tfloo- structlons to flood flO'ols. Flood stages upstream of the bridges would be even higher If debris were to catch on the bridges end block the flow area. The flood elevations shown In this report were based upon the brldgesreJl0lnlngopen. Buildings, fences and other structures In the flood plllln also obstruct flOOd flows. The area covered by the Intermediate Regional Flood varTes 10 width from 500 feet to 1,700 feet upstream of South Estes Street, while the a rell covered by the Standard Project FlOOd varies from 700 feet wide to 2,100 feet wide In the same reach. The Standard Project FlOOd rellches the fringe of a large residential area on the left bank downstream from South Estes Street. From South Wadsworth Boulevard to South Lowell Boulevard large residential areas 00 the left bank are subject to flOOding. From South Lowell Boulevard to ,the mouth several large mobile home parks are subject to flooding, as well as many permanent residences. Scattered commercial developments In the study rellch are subject to flooding IncludIng the large Bear Valley Shopping center at South Sherlelen Boulevard. The Denver office, National OceanIc and AtMOspheric AdministratIon (NOM) National Weather Service Is responsible forprovldlog flash flood warnlngsforstreal<lS In the Oenver area. The Weathl!r Service rlldllr facll- Ity at LTmon, Colorado Is capable of immediate detection and evaluation of rainfall Intensity and location and movement of storft\S and areas of heavy rainfall. River stage forecasts for Bear Creek are made by the River Forecast Center at Kansas City through the River District Office at Denver, and are based on radar coverage, reports frOM one rIver statIon, and reports frCM'T1 about 5 rainfall reporting stations In or near the basin. W""ther Service Information Is released to the news media and to local offtcl~l~ In the lIre~ of potontlal flood!ng. The Iced ti~ between forecast and flood crest Is normally about 6 hours. Large floods In other densely populated areas such as Great Falls, Montana In 1964 and In Rapid CTty, South Dakota In 1972 have demonstrated thaT some peGPle Ignore flood w..rnlngs or evacuation app"..ls until the d..nger is clo~e ..t hand. Fast peaking time during a large flood on 8