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<br />space and industrial commercial areas. The other major
<br />drainageways are fully urbanized in the Denver area and are bounded
<br />by residential development with the exception of the South Platte
<br />River and Cherry Creek, which also flow through commercial and
<br />industrial areas,
<br />
<br />2.3 Principal Flood Problems
<br />
<br />Past flooding along most of the streams in Denver has been well
<br />documented in several reports by the COE and the UDFCD,
<br />
<br />.,
<br />
<br />Large floods have been reported on the South Platte River in 1844,
<br />1864, 1867, 1876, 1894, 1921, 1933, 1942, 1965, and 1973. The
<br />largest and most damaging of these occurred June 16 and 17, 1965,
<br />when a discharge of 40,300 cubic feet per second (cfs) was computed
<br />at U.S, Geological Survey stream gage No, 06714000 near the 19th
<br />Street bridge in Denver. Flooding occurred throughout the South
<br />Platte River 8asin with six persons drowned, two other deaths
<br />caused by flood-related acd vities, and estimated damages of $500
<br />million, of which $300 million occurred in the Denver area
<br />(References 3-7),
<br />
<br />.'
<br />
<br />Past floods on Clear Creek in the Denver area have been infrequent
<br />and usually not severe in the lower reaches. The major flooding
<br />has occurred upstream from Denver, including the City of Golden in
<br />1888 (8,700 cis) and 1956 (5,250 cis), and Derby in 1965 (5,070
<br />cfs) (Reference 8),
<br />
<br />Flooding has occurred along 8ear Creek in 1876, 1894, 1896, 1957,
<br />1965, and 1969, The 1896 flood was the largest experienced, with
<br />27 lives lost and severe property damage reported from the Town of
<br />Evergreen to the mouth. The discharge at the Town of Morrison
<br />gaging station was 8,600 cfs (Reference 9).
<br />
<br />Prior to the construction of Cherry Creek Dam, major floods
<br />occurred on Cherry Creek in 1864, 1885, 1912, and 1933. 80th the
<br />1912 and 1933 floods were reported to have resulted in damages of
<br />approximately $1 mill ion (Reference 10), Construction of Cherry
<br />Creek Dam was completed in 1950, and the dam is estimated to have
<br />prevented considerable damage during the flood of June 1965.
<br />
<br />From 1942 to the present, there have been at least 14 years with
<br />major flooding events from Cherry Creek, during which flooding of
<br />premises and impedance of traffic occurred, FlOOd-causing rainfall
<br />in these years produced overland inundation of homes and streets to
<br />depths of as much as 4.5 feet. Floodflows in this area (north of
<br />Lowry Air Force Base) for these storm events were in the range of
<br />300 to 600 cfs. From 1942 through the early 1960s, flooding
<br />problems were confined to areas downstream of Lowry Air Force Base.
<br />Since approximately 1965, rainfall flood events have begun to occur
<br />in the upper watershed as a direct result of the increasing density
<br />of development (Reference 11).
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