FLOOD04327

• County: Adams
• Community: Commerce City
• Stream Name: South Platte River
• Basin: South Platte
• Title: Flood Insurance Study - City of Commerce City
• Date: 12/5/1989
• Prepared For: Commerce City
• Prepared By: FEMA
• Floodplain - Doc Type: Historic FEMA Regulatory Floodplain Information

FLOOD INSURANCE STUDY
CITY OF COMMERCE CITY, ADAMS COUNTY, COLORADO

1.0 INTRODUCTION

1.1 Purpose of Study

This Flood Insurance Study investigates the existence and severity
of flood hazards in the City of Commerce City, Adams County,
Colorado and aids in the administration of the 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
rat.es 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 and Flood Insurance Rate Map for the City of
Commerce City, dated September 30, 1988. This information will be
used by the community 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 communi ties, floodplain management cri teria 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 juris-
dictional agency) will be able to explain them.

1.2 Authority and Acknowledgments

The sources of authority for this Flood Insurance Study are the
National Flood Insurance Act of 1968 and the Flood Disaster
Protection Act of 1968, as amended. The hydrologic and hydraulic
analyses for this study were performed by Gingery Associates, Inc.,
for the Federal Emergency Management Agency (FEMA) under Contract
No. H-37l6. This work was completed in March 1977.

Additional hydraulic analyses were completed by Simons, Li and
Associates, Inc., in June 1987, to reflect channel modifications for
a reach of Sand Creek between Vasquez and Brighton Boulevards.
Revised hydraulic analyses were also conducted for a reach of the
South Platte River, from approximately 760 feet downstream of
westbound Interstate Highway 270 to the upstream corporate limits of
Commerce City at Franklin Street, by Wright Water Engineers, Inc.,
under contract to the Urban Drainage and Flood Control District
(UDFCD) .