FLOOD10485

• County: Arapahoe
• County: Douglas
• Stream Name: Big Dry Creek
• Basin: South Platte
• Title: Big Dry Creek ‎(Arapco)‎ & Tributaries - Major Drainageway Planning - Phase B Preliminary Design Report
• Date: 4/1/1998
• Prepared For: Arapahoe County, Douglas County, Englewood, Greenwood Village, Littleton, UDFCD
• Prepared By: WRC Engineering, Inc.
• Floodplain - Doc Type: Flood Mitigation/Flood Warning/Watershed Restoration

Mr. Ben Urbonas, P.E.
Mr. John Doerfer
April 30, 1998
WRC File: 1913/81
Page 2
The major drainageway drainage problems generally consist of inadequate culvert capacity under
street crossings, bank erosion (both low-flow and overbank areas), channel degradation, and flooding of
private property (homes and buildings).
The major drainageway improvements presented herein were developed from decision matrices to
obtain the most cost effective, feasible, and publicly acceptable solutions. Citizen input was solicited during
this alternatives process to obtain feedback and suggestions as to desirability and acceptability of the
proposed improvements.
The recommended drainageway improvements presented herein include street crossing
improvements and in channel improvements for a total estimated cost of $23,800,200.
In conclusion, the improvements presented herein provide a reasonable level of improvements to
minimize potential future problems (and costs). They also represent the improvements which are the most
cost effective to solve existing drainage problems.
We appreciated the opportunity to participate in this study and to prepare the enclosed preliminary
design. We hope this project assists the project sponsors in future decision making processes regarding
implementation of the proposed major drainageway improvements.
Respectfully Submitted,
WRC ENGINEERING, INC
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30, 1998

913/8

Major Drainageway Planning of Big

WRC File

April

RE: Big Dry Creek (ARAPCO) and Tributaries
Major Drainageway Planning
Phase B Preliminary Design Report

the Phase-B Prelimmary Design Report for
and Tributaries.

I~(

w~c !;NGIN!;!;~ING,

Urban Drainage & Flood Control District
2480 West 26th Avenue, Suite 156-B
Denver, Colorado 80211

Gentlemen

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P.E.

Enclosed herein

Mr. Ben Urbonas,
Mr. John Doerfer

Drainageway Planning process

Major

This report documents the

Dry Creek (ARAPCO)
from

improvements to Big

initiation of the said study through preliminary design of the Sponsors selected

This report presents a synopsis ofthe project history, public awareness process,

Dry Creek and Tributaries.

description of the study area, summary of project hydrology and hydraulics, evaluation of existing faCIlities

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and identification of drainage problem areas, discussions on the selection, evaluation, and conclusions of the

alternatives evaluation process, and the selection and preliminary design for drainage improvements to Big

north of South

generally of existing urban development
and south of South

Dry Creek and Tributaries.

The Big Dry Creek watershed consists

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University
with culverts

rapidly urbanizing areas

Ranch)

(in Highlands

University Boulevard
Boulevard.

is almost exclusively open natural or grass-lined channels

The major drainageway
The

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is contained within the main channel and large overbank areas

Notable exceptions to this occur from the South Platte River to upstream

floodplain

for a majority of the drainageway.
of South

OO-year

at street crossings.

the Julia
and/or

and from

of private property

from Orchard Road to upstream of South Franklin Street,

a significant amount

100-year floodplain

these locations,

buildings (homes) are encompassed in the

DeKovend Park to Arapahoe Road. At

Windermere Street,

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wrceng@eazy,net

.

CONSULTING ENGINEERS

[phone] · FAX [phone]

950 SOUTH CHERRY STREET · SUITE 404 . DENVER, COLORADO 80222 .

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