FLOOD08251

• County: Arapahoe
• County: Douglas
• Community: Englewood, Cherry Hills Village, Greenwood Village
• Stream Name: Little Dry Creek
• Basin: South Platte
• Title: Major Drainageway Planning
• Date: 2/1/1974
• Prepared For: Arapahoe County / Douglas County / Englwewood / Cherry Hills Village
• Prepared By: UDFCD
• Contract/PO #: &&
• Floodplain - Doc Type: Floodplain Report/Masterplan

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I N T ROD U C T ION

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This report has been prepared in fulfillment of a contract for the en-

gineering study of surface drainage in the Little Dry Creek drainage

basin.* The contract is between McCall - Ellingson & Morrill, Inc.,

Consulting Engineers, and the Urban Drainage and Flood Control District

together with Arapahoe County, the City of Englewood, the City of Cherry

Hills Village, the City of Greenwood Village, and Douglas County. The

basin lies within the jurisdiction of these named local governments.

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Purpose

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The purpose of the contract is to identify and define the basin's surface

drainage problems and to develop solutions for them. Since the early

1960's, urbanization of the basin has accelerated. There has been growing

concern as to how urbanization of the basin may affect runoff, what hazards

to present urbanization exist, and how far future urbanization should be

allowed to develop.

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The intense rains that occurred in 1965 south of the basin and the resul-

tant heavy flood damage along the South Platte River increased concern

about the drainage in the Denver metropolitan area. As a result, the U.S.

Army Corps of Engineers undertook an extensive study of existing flood

hazards in the Denver metropolitan area. Volume IV of their report, dated

1968, delineated flood plains for an Intermediate Regional Flood (lOO-year)

and a Standard Project Flood for parts of Little Dry Creek and Greenwood

Gulch. The Corps study has significant general value and serves its in-

tended purpose, but lacks specific information needed by local governments,

For example, flood plains are shown on 1 inch = 1,000 foot scale maps having

10-foot contour intervals. These are not adequate for flood plain defini-

tion and zoning purposes, Moreover, major basic criteria employed such as

rainfall, infiltration, impervious area, peak flows, and channel roughness

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* Sub-basin Nos. 1-05-5400 Little Dry Creek, 1-05-5401 Greenwood Gulch,
and 1-05-5402 Willow Creek and Spring Creek.

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