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<br />1.0 Introduction
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<br />Flooding is the one natural disaster that caused more lives to be lost and the most property
<br />damage than any other in the United States in the 20th century (perry, 2000). Floods have caused
<br />more that 10,000 deaths in the United States since 1900 and over $1 billion each year in property
<br />damage, Floods are the second most common natural disaster, behind only fire, with all
<br />communities existing with the threat of experiencing a flood (FEMA, 1998), In fact, during a 30-
<br />year mortgage, there is a 26% chance of a home located within a 100-year floodplain being
<br />flooded (CWCB, 2001), In Colorado, flooding caused 331 lives to be lost between 1900 and
<br />1993 (CWCB) and $4,9 billion in property damage to date (CWCB, 2002). With an estimated
<br />$17,6 million lost annually between 1896 and 1994 (CWCB, 2002), Colorado experiences at
<br />least one 100-year flood every year, (CWCB, 2002) In addition, United States Presidents have
<br />declared 9 major flood disasters out of32 years between 1965 and 1999 (CWCB, 2002),
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<br />A flood is defined as an instance in which water escapes the channel in which it is nonnally
<br />contained, or where there is a rapid accumulation of runoff or surface waters from any source, In
<br />other words, nonnally dry land is partially or completely inundated (CWCB, 1987), There are
<br />several different types of floods that include regional, flash, ice-jam, dam and levee failure,
<br />stonn-surge, and debris, landslide, and mudflow floods, Regional floods are those that occur
<br />seasonally in the spring when there are many thunderstonns that are coupled with the melting
<br />snow-pack, During these events, the ground may be frozen which prevents infiltration of
<br />moisture into the soil, causing an excess amount of runoff that fills river basins beyond their
<br />capacity, In addition, regional floods may occur after any extended wet periods, causing
<br />saturated soil that prevents infiltration, Flash floods are generally more devastating than regional
<br />floods since high flow velocities can develop within short amounts of time, hours or even
<br />seconds, Flash flooding has several factors that contribute, such as rainfall intensity and duration,
<br />surface conditions, and topography and slope of the receiving basin, Mountainous areas, in
<br />particular, are susceptible to flash floods because of steep and narrow canyons that funnel the
<br />runoff (perry, 2000),
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