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5.0 INSURANCE APPLICATION In order to establish actuarial insurance rates, the Federal Insurance Administration 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, and flood insurance zone designations for each flooding source studied in detail affecting Trinidad. 5.1 Reach Determinations Reaches are defined as lengthS of watercourses having relatively the same flood hazard, based on the average weighted difference in watersurface elevations between the 10 and 100-year floods. This difference did 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 Less than 2 feet 2 to 7 feet variation 0.5 foot 1.0 foot Seventeen reaches meeting the above criteria were required for the flooding sources of Trinidad. These include four reaches each on Purgatoire River, Pinon Canyon, and Portland Avenue Canyon; three reaches on Prospect Canyon; and two reaches on Fishers Peak Arroyo. All reaches are shown on the Flood Profiles (Exhibit 1). 5.2 Flood Hazard Factors The Flood Hazard Factor (FHF) is the Federal Insurance Administration device used to correlate flood informa- tion with insurance rate tables. Correlations 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 eleva- tions 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-year and 13