FLOOD09590

• County: Arapahoe
• Community: Aurora
• Stream Name: Cherry Creek Lake
• Basin: South Platte
• Title: Hydrologic Improvement Assessment Cherry Creek Lake
• Date: 9/1/1993
• Prepared For: State of Colorado
• Prepared By: US Army Corps of Engineers
• Floodplain - Doc Type: Project

GENERAL DESCRIPTION

Cherry Creek Dam was authorized by the Flood Control Acts of 1941 and 1944.
Construction began in 1946 and Was completed in 1950, Pertinent data for the
project are presented in Appendix A. The project, as originally designed, was
to be a multipurpose project with 85,000 acre-feet of storage reserved for
irrigation by the Bureau of Reclamation as a part of their Blue-South Platte
River Project. The Cherry Creek Dam project was to be built in two phases. The
first phase included only the features of the outlet works and spillway required
to accomplish the flood control function. The spillway channel was constructed
with invert elevation 5598. The second phase or ultimate development was to be
accomplished by placing an ungated ogee weir structure with a crest elevation of
5623 feet m.s.l. and an 18-foot wide notch to elevation 5598 feet m,s.l. in the
spillway and modifying the center conduit of the outlet works when the actual
need for irrigation storage developed, In 1968, the Bureau of Reclamation
relinquished to flood control the 85,000 acre-feet of storage reserved for
irrigation and, therefore, the proposed modifications to the spillway and outlet
works were never accomplished.

The existing Cherry Creek Project is a multipurpose project consisting of:

(1) A rolled. zoned, earthfill embankment 14,300 feet long with a maximum height

of 140 feet; (2) an outlet works consisting of a reinforced concrete intake

tower, gated triple barreled conduit and stilling basin; and (3) an unlined,

uncontrolled spillway canal which discharges into the adj acent Toll Gate and Sand

Creek drainage basins. At the minimum multipurpose pool elevation of 5550 feet

m.s.l., the reservoir has 852 surface acres with a volume of 13.226 acre-feet.

At the flood control pool elevation of 5598 feet m.s.l., the reservoir has 2,637

surface acres with a storage capacity of 92,820 acre-feet. The storage data are

based on 1975 reservoir data.

WATER IMPOUNDMENT HISTORY

Although construction was completed in 1950, no permanent storage was

accumulated in Cherry Creek Dam until 1957. Following the storm of 13 through

16 May 1957, approximately 1,500 acre-feet of water was impounded in the

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