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<br />Colorado Flood Hazard Mitigation Plan - 1999
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<br />Chapter 2 - Hazard Identification and I alnation
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<br />2.1 People and Hazards
<br />The relationship between flood hazard" and population
<br />identifies patterns of risk, as shown in Figure 2_1 Re-
<br />lationships between patterns of risk and steps taken
<br />toward preparedness explain degrees of vulnerability
<br />to which various Coloradans are exposed.
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<br />Such relationships are not new to Colorado, The natu.
<br />ral phenomena involved have occurred here long be,
<br />I fore people settled near them and were impacted by
<br />them. Risk grows from the increasingly close associa~
<br />tion between natural phenomena and a growing popu,
<br />lation
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<br />Figure 2.1-Relationships to Risk
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<br />People become vulnerable to haza:-ds when they
<br />choose (knowingly or unknowingly) to live near the ar,
<br />eas where these extreme events OC:Cl!L Vulnerability
<br />is also related to preparedness. People who prepare
<br />for the occurrence of an extreme event are less vulner~
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<br />For More Informatiol~
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<br />Appendix A - Includes definitions, acronyms,
<br />and references used in the
<br />preparation of this plan,
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<br />Appendix B - Includes Information 0'1 financial
<br />assistance programs,
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<br />Appendix C - Includes tips to minimiz.e loss of
<br />life & property in the event of a
<br />flood,
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<br />Appendix 0 - Includes mitigation strategies and
<br />measures.
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<br />Appendix E - Includes mitigation planning
<br />examples.
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<br />Chapt"r 2 - 1
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<br />able to it than those who do not. The vulnerability of
<br />Colorado's population is rooted in a relationship be-
<br />-r..veen the occurrences of extreme events, the prox-
<br />imity o'r people to these occurrences, and the degree
<br />to which these people are prepared to cope with these
<br />extremes of nature.
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<br />I Today, 'flood prone areas have been identified in 268
<br />crties and towns and in all of the 63 counties in Colo-
<br />rado. Using information supplied from local units of
<br />government, there are estimated to be approximately
<br />250,000 people now living in Colorado's floodplains
<br />The Colorado Water Conservation Board I:C\NCB) esti-
<br />mates that approximately 65,000 homes and 15,000
<br />commercial and industrial business structures are lo~
<br />cated in Colorado's floodplains, Note, One of the rec.
<br />ommendations of this plan is to begin to inventory the
<br />structures and people in Colorado's floodplain. This
<br />inventory, when completed, will enable planners at the
<br />state and local level of governments to plan and miti-
<br />gate thE' flood hazard, The total value of property, in-
<br />cluding structures and contents, exposed to the 100-
<br />year flood in Colorado is estimated to be over $11 bil-
<br />lion donars. Cumulative flood losses fror1 the turn of
<br />the century to 1999 from the state's most damaging
<br />floods a'e $3,3 billion (1999 dollars)
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<br />2.2 Types of Hclzards
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<br />2,2,1 Fiooos
<br />Floods in Colorado occur on "riverine" systems con-
<br />SIsting of a basin (or watershed) and a hierarchical or-
<br />dl3r of stream channels that convey the normal flow of
<br />vvater throll!}h the watershed. The area adjacent to the
<br />channel is the floodplain. Flooding results when the
<br />Flow of water is greater than the normal carrying ca-
<br />pacITY <)'! the stream channeL Rate of rise, magnitude
<br />I" :or peak discharge), dumtlon, and frequellcy of floods
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<br />are a function of specific physiographic characteristics
<br />Ceneraliy the rise in water surface elevation is quite
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<br />Webstel"s Definitions
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<br />F/lJ'ocf:
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<br />a temporary condition of
<br />inundation of normally dry
<br />land areas
<br />a soulCce of danger
<br />to cause to become I,ess
<br />harsh or hostile, to make
<br />less severe
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<br />Hazard:
<br />Mitigate:
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