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I I I I I I I I I I I I I I I I I I I Cedaredge is located in the Gunnison River Basin. The Gunnison River ba..in has a Iota I area of over 8.000 square miles and is home to 79.300 people. There are 195 instream flow segments that total 1.219 miles of streams and 83 natura) lakes. The historical flood damage in this basin in estimated to total around $13.9 million to date. A historical representation of the water conditions in the Gunnison River basin is represented below in Figure 2 (eWes. 2002). SMr CWd"'~mw!)"""rJ~W~ ~~ rtIU(j Amel99J Bnm ~ooo. ._.~_f - Dry A\IQ We! ,~ "" B_, r_. Junel~7 Se1:>1191D PoA'Y "roug~ 8.sm Ico<l. Bum IIoods .kJne'9M B...nlloodl , , i j g j j i j j j j ~ I ; ~ j i si 8, ure J.Historica/ Gunnison River Water Conditions In order to prove that the post-disaster expense in fact does greatly exceed the pre-disaster mitigation expense. Grimm (1998) examined the 1997 Spring Creek flood in Fort Collins. Colorado. This 500-year flash flood event occurred on July 28. 1997 as a result of a convective storm and resulted in five deaths. 62 hospitalizations. and more than $250 million in property damage (Weaver et al.. 2(x)()). In the decade prior to the flood. the City of Fort Collins spent $5 million in pre-disaster mitigation efforts that include removing 86 structures (45 of which were residential or commercial) from the IOO-year floodplain. The removal of these structures is estimated to have saved 98 lives and $8.4 to $14.5 million. The total bill for damages based on thi... assessment is estimated to have reduced the total bill by $5.6 to $9 million. This analysis does not include other mitigation efforts. such as education. included in the $5 million budget. Therefore. it can be concluded that the pre.disaster mitigation efforts were very much worth the cost (Grimm. 1998). There are several hydrologic methods that may be used to determine the peak discharge for the stream reach including the Rational Method. Regional regression equations. statistical analysis. or RainfalLlRunoff Models. The method that will be used depends on the data that are available. The Rational Method can be used for small catchments with areas of less that 200 acres 12