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<br />. the flooding pattern on the fan, <br />. prediction of future flood behavior, <br />. existing and projected development, and <br />. the effectiveness of the various management <br />tools available. <br /> <br />In the past, measures have often been selected with little <br />understanding of the dynamics of flooding on fans and little <br />con~ern for the effect of development density on measure <br />performance. This has led in several instances to the <br />failure of levees. dikes, and other installations and very <br />heavy damages to properties on the fans. <br /> <br />The following selection process considers all of the key <br /> <br /> <br />issues which influence management tool pe~formance and <br /> <br /> <br />ensures a comprehensive approach to flood plain management <br /> <br /> <br />on alluvial fans. <br /> <br />,. The ~ and location Qi flood hazards on the <br />fan should be identified based on a qualitative <br />analysis of fan and watershed characteristics <br />and a review of historical flooding behavior. <br />A geologist and a hydrologist would be required <br />to analyze the characteristics and predict <br />future fan behavior. Sections 3, and 4 deal <br />with these issues. <br /> <br />2. Quantitative estimates for the depth, <br /> width an..!! .E.ll!l Qi the desicn flood <br /> event) should be developed from <br /> formulas for channel geometry and <br /> <br />veloci~YI <br />( 100-year <br />emp i ri ca 1 <br />beha'Jior. <br />Several formulas for computing these quantit"es <br />are presented in Part II. Section 3 of this <br />report. <br /> <br />3. <br /> <br />The identification of <br /> <br />e~istinc ann future <br /> <br />72 <br />