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<br />experienced flooding or that contributed to flood flows on the South Platte River are Bear Creek,
<br />Cherry Creek downstream from the dam, Clear Creek, oil. \train Creek, Big Thompson River, and
<br />Cache la Poudre River,
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<br />4,1.2 PLUM CREEK BASIN
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<br />Flood History, The following accounts illustrate flood potential in the Plum Creek basin,
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<br />Flood of Seotember 1933, On 10 September 1933, a cloudburst occurred over the South Platte
<br />Paver between Denver and the foothills, wtth the center over Plum Creek, Little Dry and Big Dry Creek
<br />basins, Although information on tributary flows is limited, it was estimafed that the Plum Creek peak
<br />discharge below the confluence of the East and West Branches was about 30,000 cubic fE'et per
<br />second attenuating to about 5,500 cubic feet per second at the mouth,
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<br />Fiood of 16-17 June 1965, The flood of June 1965 is without questions the most disastrous flood
<br />event in terms of dollar damage that has ever occurred in the South Platte basin. The flood was the
<br />result of runoff from heavy intense rainfall occurring on the evening of 16 June, centered over the high
<br />plains area of the Plum Creek and Cherry Creek basins, Runoff from the Plum Creek area produced
<br />a major disaster not only the tributary itself, but also along the South Platte River through Denver,
<br />beginning at the point where Plum Creek empties into the South Platte and extending downstream
<br />through Denver and on below through the rural area along thE) South Platte River.
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<br />4,1,3 LITTLE DRY CREEK BASINS
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<br />Flood Historv, Descriptions of two floods occurring on Little Dry Creek in Arapahoe County are
<br />representative of the effects of severe storms in an area of extensive urban development Tile
<br />September 1933 flood is an example of a severe storm extending over several watersheds, This storm
<br />affected Little Dry Creek, Big Dry Creek, Plum Creek, ancl Cherry Creek, The simultaneous flooding
<br />of these four streams was the priman; cause of flooding on the South Platte River,
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<br />Flood of 10 Seotember 1933, Heavy rains of cloudburst proportions centered over the Little Dry
<br />Creek basin and resulted in the greatest flood of record, The estimated discharge of the stream during
<br />the flood was 10,000 cubic feet per second, Water rose in the residences as much as 3 feet above
<br />their firsHloors, Heavy damages also were inflicted on business establishments and utilities in
<br />Englewood with some of the business buildings moved off their foundations by the high velocities.
<br />Floodwaters extended from two blocks north to a half block SOUtll of the channel throughout its course
<br />through the urban area, Almost all of the street and highway bridges in Englewood were severely
<br />damaged and the total loss was estimated at approximately $180,000, Englewood Dam was later
<br />constructed on this stream, but a storm of this magnitude would still cause serious flooding,
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<br />Flood of 3 August 1956, A series of storms between ,10 July and 3 August over the Denver area,
<br />including the Little Dry Creek basin culminated in more than 12 inches of rain being reported, for the
<br />period, in Englewood and the surrounding areas, Debris,blocked channels forced Little Dry Creek out
<br />of bank at several locations in Englewood and discharges exceeded channel capacity below the town,
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<br />Colorado Flood
<br />Hydrology Manual
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<br />4.4
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<br />DRAFf
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