Laserfiche WebLink
<br />IJ <br /> <br />data are the input relationships. Thus, for each input data year and <br />plan the estimated flood damage for a specific flood event (specified <br />by stage or flow) can be computed. Up to 18 events may be specified. <br /> <br />13. EXPECTED ANNUAL FLOOD DAMAGE <br /> <br />Expected annual damage is the frequency weighted sum of damage <br />for the full range of damaging flood events and can be viewed as what <br />might be expected to occur in any present or future year. It represents <br />the annual damage for a particular set of hydrologic, hydraulic and damage <br />conaitions. In the computer program expected annual damage'is computed <br />for each input data year, the study year, the base year and each decade <br />year by first computing a damage-frequency relationship from stage, flow, <br />frequency and damage data for each reach, plan and damage category. Each <br />damage value is then weighted according to its percent chance of occurrence. <br />An explanation of this integration routine is presented in Exhibit 2. <br /> <br />Within the period of analysis expected annual damage is computed for <br />each year. This is done by first computing expected annual damage for <br />the base year, each decade year (every 10 years from the beginning of <br />operation), and for each input data year. Stage, flow, and damage data <br />for each input data year are uSed to compute similar data for the base and <br />decade years. Between any pair of input data years, the stage, flow, and <br />damage data for the base or decade years are computed by linear interpolation. <br />Outside any pair of input data years or for a single input data year, <br />the stage, flow and damage data are assumed to be the same as for the last <br />or single input data year. As an example, if the last two input data years <br />were 2005 and 2015 and the last year of the analysis were 2020, the stage. <br />flow and damage data for decade year 2010 would be obtained by linear inter- <br />polation of stage. flow and damage data. Data for 2020 would be the same <br />as for input data year 2015. <br /> <br /> Input Data Years <br />t t t <br /> I <br /> ~ <br /> I <br />Base t t t t t <br />Year Decade Years <br /> v <br /> Period of Analysis <br /> <br /> <br />9 <br />