FLOOD07780

• County: Eagle
• Community: Eagle County
• Basin: Colorado Mainstem
• Title: Hydrology Addendum FIS - Eagle County Unicorporated Areas
• Date: 2/1/2002
• Prepared For: CWCB
• Prepared By: Montgomery Watson Harza
• Floodplain - Doc Type: Floodplain Report/Masterplan

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INTRODUCTION

Pul1lose and Scope
This Hydrology Addendum (HA) was prepared to provide supporting documentation for the
approximate lOG-year floodplain boundaries shown in the Eagle County Unincorporated Areas
PIS, dated January 25, 1983. The FIRMs were prepared using both detailed and approximate
floodplain mapping techniques. Engineering information was not provided by FEMA to support
the approximate floodplain delineations shown on the FIRMs. This HA provides limited
engineering information to fulfill that need.

This HA includes:

i. Authorization for the report and its purpose and scope;

2. Study area description including information on the communities, the watershed, any known
flooding history/tlooding problems, previous studies and projects, and community response
to the CWCB designation and approval process;

3. Description of hydrologic and hydraulic information; and

4. Floodplain management program.

Authorization
The CWCB has certain statutory responsibilities relating to the designation and approval of
floodwater runoff channels or basins as follows:

... "to devise and formulate methods, means, and plans for bringing about the greater
utilization of the waters of the state and the prevention of flood damages therefrom, and
to designate and approve storm or floodwater runoff channels or basins, and to make such
designations available to legislative bodies of cities and incorporated Counties, to County
planning commissions, and to boards of adjustment of cities, incorporated Counties, and
counties of this state"... Section 37-60-106(1)(c) of the Colorado Revised Statues (CRS).

A CWCB designation and approval of current floodplain information is needed for the
unincorporated areas of Eagle County, Colorado. The CWCB has prepared this HA as a means
of designating the Eagle County FIRMs so that the communities can better implement its
floodplain management program.

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