FLOOD10403

• County: Statewide
• Basin: Statewide
• Title: Colorado's 1997 Flood Season In Review
• Date: 8/1/1998
• Prepared For: CWCB
• Prepared By: Riverside Technology, Inc.
• Floodplain - Doc Type: Educational/Technical/Reference Information

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In trod uction

1.0 INTRODUCTION

1.1 Project Summary

During late July and early August of 1997, 13 counties in Colorado (Baca,
Clear Creek, Crowley, Elbert, Kiowa, Larimer, Lincoln, Logan, Morgan,
Otero, Phillips, Prowers, and Weld) experienced intense rainfall and flooding
to such a degree that President Clinton declared them eligible to receive
federal disaster assistance for damages caused by the heavy rain, flash
flooding, mudslides, landslides, and severe ground saturation. A map
showing the locations of the affected counties is provided in Figure 1.1-1.
Each county experienced varying degrees of flooding and damage and
responded to a myriad of disaster-related situations. The types of flood
damage ranged from washed out county roads, erosion of railroad
embankments and ditches, destruction of property, inundation of lands, and
the loss of five lives in Fort Collins [State of Colorado and FEMA (Federal
Emergency Management Agency) 1997]. In addition to the 13 declared
counties, several other counties and communities experienced flooding
damage dwing the 1997 flood season, which extended from approximately
June through September.

This document summarizes data collected, analyses performed, damage
suffered, mitigation activities conducted, and general trends observed in the
13 counties and around the state dwing the 1997 flood season. More
specifically, the subsequent chapters of this document define and describe
the flood-impacted areas within the 13 disaster counties and throughout the
state, provide flood histories for these regions, define the hydrologic and
hydraulic information related to the storm events dwing. this period,
describe mitigation efforts and damage, and graphically illustrate the
severity of damage experienced in many locations.

During the 1997 flood season, storm systems drenched other areas in
northeastern Colorado, as well as several counties in southern Colorado. The
Denver Metropolitan Area and Routt County also received flooding rains.
Although these areas were not included in the presidential disaster
declaration, relevant information from these areas is an important
component in understanding the effects of such intense rainfall events on a
statewide basis. To illustrate the flood events of 1997 as clearly as possible,
information from non-declared areas also is included in this document.

1.2 Purpose of Study

In order to be better prepared for flooding events in the future, the objective
of producing this document is to summarize all of the available statewide
information regarding the flooding events in 1997 to facilitate mitigation

d479/chap1.doc 08/12/98

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