FLOOD03283

• Designation Number: 349
• County: Adams
• Community: Unincorporated Adams County
• Stream Name: Beebe Draw and Left Bank Tributaries
• Basin: South Platte
• Title: Flood Hazard Area Delineation - Beebe Draw and Left Bank Tributaries
• Date: 7/1/1993
• Designation Date: 1/1/1994
• Floodplain - Doc Type: Floodplain Report/Masterplan

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II. PURPOSE AND SCOPE

Acknowlede:ements
This report was prepared by Kiowa Engineering Corporation under contract with the
UDFCD.
Topographic mapping and digitized cross sections were provided by Landmark Mapping
Ltd. Original mapping was prepared with two-foot contour inteIVals at a scale of I" = 100'. The
[mal floodplain maps were reduced by 50 percent to facilitate inclusion in this report.
The mapping was prepared according to the specifications of the UDFCD, and meets
National Map Accuracy Standards. Ground control surveys for the topographic mapping were
performed by Landmark Mapping, Ltd. Aerial photography was prepared by Rocky Mountain
Aerial Surveys, Inc. The aerial photography is dated December 29, 1991.

This report was prepared to guide local government officials in planning the use and
regulation of the lOO-year floodplain. The report includes bformation on the nature and extent
of probable future floods along 4.5 miles of Beebe Draw in northern Adams County and about
one mile each of Magpie Run, Meadowlark Run and Redwing Creek between Interstate 76 and
Beebe Draw.
The loo-year flood should be given appropriate consideration before planning further
development in the drainage basin, and within the floodplain. The report provides a suitable
basis for the adoption of land use controls to guide floodplain management and minimize flood
losses. Flood water surface elevations and floodplain boundaries are often revised by road and
bridge construction, floodplain development, flood control improvements, or natural processes.
Prior to utilization of this report for planning or design purposes, the user is advised to contact
the local government, UDFCD, or CWCB to determine if the information in this report has been
amended.
This report was prepared following the format of the UDFCD's Flood Hazard Area
Delineation (FHAD) Reports. The scope consists of the following items:

1. A summary of pertinent data or information.

2. Identification of major basin features.

3. History of the stream relative to flooding, and a description of various hazards associated
with the areas in or near the 100- year floodplain.

4. Hydrologic analysis including rainfall data, drainage basin parameters, flood flows, and
design hydrographs.

5. Hydraulic analysis and summary of hydraulic data.

6. Plan and profile information, including loo-year floodplain limits, 10- and loo-year
flood profiles showing the water depths relative to the stream bed, typical cross-sections,
locations of all cross-sections utilized in hydraulic computations, and design flows and
velocities at appropriate locations.

7. Tabulation of flood hazard information for each cross section including section number;
reference stationing; thalweg elevation; 10-,50-, and loo-year discharges and water
surface elevations; loo-year flood water surface elevation; top width of proposed
floodway; floodway width on left and right side of thalweg; floodway water surface
elevation; and mean velocities of loo-year flood for both floodplain and floodway.

8. The determination of a floodway based on an equal degree of encroachment which
results in a total water surface elevation increase of no more than one-half foot.

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