FLOOD10351

• County: Statewide
• Community: Statewide
• Title: Statewide River Rehabilitation & Flood Plain Management Needs Inventory
• Date: 12/1/1998
• Prepared For: State of Colorado Department of Natural Resources
• Prepared By: McLaughlin Water Engineers
• Floodplain - Doc Type: Floodplain Report/Masterplan

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CHAPTER I
",INTRODUCTION AND BACKGROUND
'" --

The Statewide Needs Inventory was initiated by the Colorado Water Conservation Board (CWCB) in
response to the flood losses, channel conveyance, and stream bank stability problems experienced
statewide during the flood events of 1993,1995, and 1997. In the 20th Century, Colorado communities
have experienced over $4.9 billion in direct flood damage to homes, businesses, public buildings and
utility infrastructure and suffered unmeasured loss of water supply capacity and environmental quantity.

Between July 28 and August 17, 1997, extreme flooding impacted a thirteen-county area of Colorado as a
result of a monsoonal storm system, which stalled over the front range area. Point rainfall amounts of 8.3
inches to 15 inches were recorded. An estimated $170 million in flood damages resulted in the Fort
Collins/Larimer County area, and an additional $50 million in damages occurred in twelve other counties.
Six deaths were attributed to the flooding and the thirteen-county area received a Presidential Disaster
Declaration.

Stream and riverine flooding has always been, and remains to be, the greatest natural hazard to life and
property in Colorado. TOday, flood prone areas have been identified in 268 cities and towns and in all of
the 63 counties in Colorado. Based on estimates by the CWCB staff, 250,000 people reside in Colorado's
1 DO-year floodplains, with property valued at over $16.5 billion. There is a clear need for improved flood-
plain management efforts to reduce the at-risk population's vulnerability to flooding, prevent further
encroachment into flood hazard zones and preserve the natural resources and functions of the floodplain
areas.

Floodplain areas in stream corridors have many uses other than conveyance of floodwaters; these include:
· Opportunities for outdoor recreation,
· Open space,
· Preservation of riparian and aquatic wildlife habitat,
· Preservation of wetlands.

Such uses of floodplain areas and stream corridors are becoming increasingly important. Little demand
exists for the single purpose flood control project of the past; today, municipalities and other governmental
and private entities with responsibility for flood damage reduction and/or stream corridor management are
demanding multiple purpose projects, which not only provide for floodplain management, but meet needs
for outdoor recreation, open space, wildlife habitat and wetlands preservation.

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