FLOOD10157

• Designation Number: 74
• County: Arapahoe
• Community: Aurora
• Stream Name: Granby and Sable Ditches
• Basin: South Platte
• Title: FHAD - Granby and Sable Ditches, Aurora, Colorado
• Date: 4/1/1977
• Designation Date: 7/27/1977
• Floodplain - Doc Type: Floodplain Report/Masterplan

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as stated in Section 30-28-201 for county governments and
Section 31-23-201 for municipal governments of the Colorado
Revised Statutes 1973.

PREFACE

This report was authorized by the Urban Drainage and Flood
Control District in joint sponsorship with the Federal
Insurance Administration and the Colorado Water Conservation
Board. The District has the power to enact District-wide
flood plain regulations. At present, the District makes flood
plain information and mapping available for local agencies to
adopt and administer their own flood plain regulations with the
assistance of the District.

Upon acceptance of this report by the Urban Drainage and Flood
Control District and the designation and approval of this report
by the Colorado Water Conservation Board, the areas described
as being inundated by the 100-year flood (Intermediate Regional
Flood) can be designated as flood hazard areas and their use
regulated accordingly. It should be noted that the terms
"Intermediate Regional Flood", "lOO-Year Flood" and "one
percent flood" can be used interchangeably as they are all
defined by the same type of flood event.

Authorization

Purpose and Scope

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The Colorado Water Conservation Board has the power and duty

"...to designate and approve storm or floodway runoff
channels or basins, and to make such designations available
to legislative bodies of cities and incorporated towns;
to county planning commissions; and to boards of
adjustment of cities; incorporated towns; and counties
of this state..."

This report was prepared for the guidance of local officials
in planning the use and regulation of the flood plain. The
report includes information on past floods and the nature and
extent of probable future floods which can be reasonably
expected on the respective study reaches. The 100-year flood
should be given appropriate consideration before planning
for development in the flood plain.

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as stated in Section 37-60-1-6 (1) (c) of the Colorado Revised
Statutes 1973. The cities, incorporated towns and counties
within the study area may provide zoning regulations

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"...to establish, regulate, restrict and limit such uses
on or along any storm or floodwater runoff channel or
basin, as such storm or floodwater runoff or basin has
been designated and approved by the Colorado Water
Conservation Board, in order to lessen or avoid the
hazards to persons and damage to property resulting from
the accumulation of storm or floodwaters..."

The 100-year flood plain is shown on the Flood Hazard Area
Delineation Maps which delineate the areas that would be
inundated by such an event. Flood profiles show the water
depths relative to the stream bed. Elevation reference data
is given that can be applied across the full width of the stream
valley. Valley cross-sections are presented to indicate ground
level across the valley at specified locations and the overlying
flood depths. The flood profiles and flooded area data
presented are based on future, developed conditions in the