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5.0 INSURANCE APPLICATION In order to establish actuarial insurance rates, the Federal Emergency Management Agency has developed a process to transform the data from the engineering study into flood insurance criteria. This process includes the determination of reaches, Flood Hazard Factors (FHFs), and flood insurance zone designations for each flooding source studied in detail affecting the unincorporated areas of Moffat County. 5.1 Reach Determinations Reaches are defined as lengths of watercourses having relatively the same flood hazard, based on the average weighted difference in water-surface elevations between the 10- and 100-year floods. This difference does not have a variation greater than that indicated in the following table for more than 20 percent of the reach: Average Difference Between 10- and 100-Year Floods Var iation Less than 2 feet 2 to 7 feet 7.1 to 12 feet More than 12 feet 0.5 foot 1. 0 foot 2.0 feet 3.0 feet The locations of the reaches determined for the flooding sources of Moffat County are shown on the Flood Profiles (Exhibit 1) and sununar ized in Table 3. 5.2 Flood Hazard Factors The FHF is the Federal Emergency Management Agency device used to correlate flood information with insurance rate tables. Correla- tions between property damage from floods and their FHF are used to set actuarial insurance premium rate tables based on FHFs from 005 to 200. The FHF for a reach is the average weighted difference between the 10- and 100-year flood water-surface elevations expressed to the nearest one-half foot, and shown as a three-digit code. For example, if the difference between water-surface elevations of the 10- and 100-year floods is 0.7 foot, the FHF is 005; if the difference is 1.4 feet, the FHF is 015; if the difference is 5.0 feet, the FHF is 050. When the difference between the 10- and 100-year water-surface elevations is greater than 10.0 feet, accuracy for the FHF is to the nearest foot. 5.3 Flood Insurance Zones After the determination of reaches and their respective FHFs, the entire unincorporated area of Moffat County was divided into 25