FLOOD00668

• County: Arapahoe
• County: Douglas
• Community: Englewood, Littleton, Greenwood Village
• Stream Name: Big Dry Creek
• Title: Major Drainageway Master Plan
• Date: 6/1/1975
• Prepared For: Englewood, Littleton, Greenwood Village
• Prepared By: UDFCD
• Contract/PO #: &&
• Floodplain - Doc Type: Floodplain Report/Masterplan

The terms "drainage master plan" and "report" are meant to

be interchangeable and arc used synonymously throughout this

report.

The term "entities" refers to the participating citi.es

and counties, including the City of Littleton, the City of

Englewood, the City of Greenwood Village, Arapahoe County and

Douglas County, all within whose boundaries the Big Dry Creek Basin

lies; and the Urban Drainage and Flood Control District.

Section I of this report is an analysis of the established

criteria for drainage as set forth by the involved entities, as well

as an examination of the U.S. Department of Housing and Urban Develop-

ment Flood Policy and the Flood Plain Regulation of the Urban Drainage

and Flood Control District.

Section II is a generalized reVIew and analysis of the soil

types which prevail in the Big Dry Creek Drainage Basin and their

effect upon the amount of storm water runoff,

Section III is an analysis of the basin hydrologic and hydraulic

studies and the determination of the peak rate and volume of runoff

for various flood frequencies and drainage basin conditions.

Included

is a sample calculation showing the derivation of a storm hydrograph [or

a 100-year frequency flood under proposed land use conditions for the

Big Dry Creek Drainage Basin.

Section IV presents three plans for drainage improvements on a

reach by reach basis which would alleviate major flood hazards In the

basin.

Each plan includes potential flood damage and estimated

valuation of damages for each storm flequency, a description of proposed

improvements and estimated improvement costs, benefit/cost analysis

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