FLOOD08741

• Designation Number: 322
• County: La Plata
• Community: Durango
• Basin: San Juan/Dolores
• Title: Flood Insurance Study - Durango, Colorado
• Date: 12/1/1989
• Designation Date: 7/1/1992
• Floodplain - Doc Type: Floodplain Report/Masterplan

"..~

FLOOD INSURANCE STUDY
CITY OF DURANGO,LA PLATA COUNTY, COLORADO

1.0 INTRODUCTION

1.1 Purpose of Study

This Flood Insurance Study investigates the existence and severity
of flood hazards in theCi ty of Durango, La Plata County, Colorado,
and aids in the administration of th~ National Flood Insurance Act
of 1968 and the Flood Disaster Protection Act of 1973. This study
has developed flood risk data for various areas of the community
that will be used to establish actuarial flood insurance rates and
assist the community in its efforts to promote sound floodplain
management. Minimum floodplain management requirements for
participation in the National Flood Insurance Program (NFIP) are set
forth in the Code of Federal Regulations at 44 CFR, 60.3.

This Flood Insurance Study revises and updates a previous Flood
Insurance Study/Flood Insurance Rate Map (FIRM) for the City of
Durango, Colorado. This information will be used by the City of
Durango to update existing floodplain regulations as part of the
Regular Phase' of the NFIP. The information will also be used by
local and regional planners to further promote sound land use and
floodplain development.

In some states or communities, floodplain management criteria or
regulations may exist that are more restrictive or comprehensive
than the minimum Federal requirements. In such cases, the mOre
restrictive criteria take precedence and the State (or other
jurisdictional agency) will be able to explain them.

1.2 Authority and Acknowledgments

The SOurces of authority
National Flood Insurance
Protection Act of 1973.

for
Act

this
of

Flood
1968

Insurance
and the

Study are the
Flood Disaster

The hydrologic and hydraulic analyses for the original study were
performed by Camp Dresser & McKee, Inc., for the Federal Emergency
Management Agency (FEMA) , under Contract No. H-4014. This work was
completed in December 1977.

This study was revised to show the effects of the new U.S. Highway
160/550 By-Pass Bridge and fill along the Animas River on the base
flood elevations (BFEs), the floodplain boundaries, and the floodway
boundaries. Computations for the revised hydraulic analysis,
through the use of the U.S. Army Corps of Engineers (COE) HEC-2 step
backwater computer program, were performed by Goff Engineering &
Surveying, Inc. and the findings were presented in the report
entitled "Floodway and Flood Elevation Modifications, MP 63.000 to
MP 63.251, Durango, Colorado," (Reference 1). The BFEs, floodplain