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<br />, <br />\ <br /> <br />=1 <br />\ <br /> <br />\ <br />, <br />\ <br />I <br />I <br />I <br /> <br />by manually setting up several sets of flow data (with each less <br />than KPER) or by allowing the computer to generate separate floods (when <br />the data read exceeded KPER). A minimum of a 10 period overlap between <br />floods is used to preserve continuity in channel routing. <br /> <br />m, Expected annual damages <br /> <br />(1) Expected annual damages can be computed for any or all control <br />points (nonreservoirs) using one or more ratios for each of several <br />historical or synthetic floods (minimum combination of six events <br />recommended) as described in Exhibit 4. <br /> <br />(2) Damages for a single flood or a series of floods can be <br />computed if only those floods are operated in a given computer run. <br /> <br />(3) Expected annual damage (or damages for a single flood) will <br />be computed for the following three conditions: <br /> <br />(a) Natural or unregulated conditions <br /> <br />(b) Regulated conditions due to the reservoir system assumed <br /> <br />(c) Unlimited flood control storage at all reservoir sites <br />(uncontrolled local flows) <br /> <br />(4) Damages calculated for natural flows using selected floods <br />and ratios are adjusted to expected annual damages by integrating the <br />natural damage-frequency curve. A predetermined expected annual damage <br />may be input and the succeeding calculations will be adjusted by the <br />ratio to the computed damages. <br /> <br />(5) The expected annual damages for modified conditions and for <br />the uncontrolled local flows are based on flow values determined by a <br />linear interpolation between each flood event; expressed as a ratio to <br />the natural flow. <br /> <br />(6) Up to 9 different damage categories may be used. <br /> <br />(7) If the proposed system contains existing reservoirs. the <br />damage reduction can be evaluated from a base condition which is for the <br />existing system. <br /> <br />(8) Expected annual damages, costs and system net benefits for <br />flood damage reduction can also be evaluated for nonreservoir alternatives <br />such as levees, channel improvements and nonstructura1 alternatives <br />(flood proofing, relocation, flood plain zoning, etc.). Training Document 7 <br />"Analysis of Structural and Nonstructura1 Flood Control t1easures Using <br />Computer Program flEC-5e" demonstrates the program's appHcation to damage <br />calculation. <br /> <br />~ <br /> <br />9 <br />