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<br />PAST FLOODS
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<br />Flood Rocords
<br />The St~te of Color~do oparates a gaging statIon on Bear
<br />Creek ~ short d I stance upSTream of the State Highway 8 bridge In
<br />Marrl son. 01 scharge rocords ~re ava II05ble for a period of 60 Ymlrs.
<br />Thereare23koown lnsT05ncesof floods in the basIn that caused the
<br />loss of 45 lives and considerable property damage. Floods occurred
<br />In 1866, 1878(2l,1885, 1886, 1893,1894, 1896, 1903,1907, 1908,
<br />1921 (2l, 1923,1925, 1933, 1934, 1938, 1946, 1957(2), 1965,and 1969.
<br />Most of the floods were caused by runoff from Intenserelnfall during
<br />sull'l1ler storms. However, In earlier seasons r"lnf,,11 runoff coincident
<br />wIth soo"""",lt runoff has ceused floodIng conditIons. The racord flow
<br />of 8,600 c.f.s. for Dear Creek occurred on 24 July 1896. There are
<br />no gage records for Mount V"rnonCreek; the peakdischar'1C during tho
<br />1938 flood was estimated to ~e 9,230 c.f.s.
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<br />Flood Descriptions
<br />Some 01 the past major floods on Beer Creek and Mount
<br />Vernon Creek are descrIbed to Illustr"tetht>lloodpotOlMtlatlit
<br />Morrison. One of the earliest reports concerns a storm on 21 through
<br />23 ~~a y I 676, ...h I ch ...a s reported by t he Denver Tr I bu ne 01 5 June 01
<br />thatyei'lr, "... lnfonns us that he has never s\'Jen suclldestructlon
<br />In the region as resulted from the late stann. He spent some days
<br />In the valleys 01 Soda and 8ear Creeks and their tributaries and
<br />found no"gulllos worn to thodopth of 20 feet In thellctlon of the
<br />raging torrents." Anotherroport state<:l that a widespread storm on
<br />29Maytllrough I June 1894, In the vicinity of Morrison, produced
<br />a flood that caused the loss of bridges, railroad tracks, houses,
<br />and destroyed the highway In the canyon.
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<br />This section summarizes d"faon past storms and floo:.lsin
<br />theBearCreekb<lslnto IllustratetheflOOdcnaracter;stlcsof Bear
<br />Creek and Mount Vernon Creek.
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<br />24 July 1896
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<br />Duration and Rate of Rise
<br />Floods in tha study reactlesarochar<lcterizod lly rapId
<br />concentration of runoff, sharp peak discharges, and rapId flood
<br />recession. The peaking tIme lor floodsCln Bear Creek at Morrison
<br />Is "bout 3 to 5 hours after the causing nllnfllll, while Mount Vernon
<br />Creeklloodspeak In from Ito3hours. Several local residents
<br />st05t&d that during the Mount Vernon flood of 2 and 3 September 1938
<br />It ""5 about I 1/2 to 2 hours Irom the time the flood reached '~orrlson
<br />until the water had receded enough to permit tr..v..1 <>n Main Street.
<br />A large flood on Bear Creek at MorrIson due to Intense raInfall might
<br />last up t" 12 hour'S; thf' ~"r"tlon <>1 f 100:.1 Tn<] cou Id be e~tendfld even
<br />more In the CaSe 01 coincident high sno"",elt runoff.
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<br />Intenser"lnfall on 24 July 1896 centered on Cub Cre"k,
<br />a tributary of Bear Creek, no"rEvorgreen. "Wlthoutarooment's
<br />warning the largest Ilood that ever Came down Rei'lr Creek struck
<br />Morrison about 8 o'clOCk tonight (July 24l, sweeping everything In
<br />Its path ... although the water came down through the town n0i5rly
<br />3 feet deep In tha maIn streat, the buildings in the lluslnsss sectIon
<br />all withstood it."jj T"'enty-sovenllveswerc lost In tile 11000
<br />Cav"llable records do not indlCdta where the d8<.lths occurred) and
<br />severe damages were reported from Evergreen to the mouth of Bear
<br />Creek. Noralnlallrecordsofthisfloodareav05llable. Thereak
<br />tlow on Bear Creek at tho Morrison gaging st"tlon waS 8,600 c.t.s.,
<br />whiCh Is the flood of record. The most recent hydrologic studies
<br />Indicate thaf this flood would have a In 40 chance of occurring
<br />In any y""r. It Is not known to what extent Mount Vernon Creek
<br />contributed to tho Morrlzon flooding,
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<br />Rocky Mountaln News, Ju Iy 2~, 1896, quote<l In "F loads I n Colorado,"
<br />U.S.oeoartmentof Interior,W.S.Paper997.
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