Laserfiche WebLink
<br />boundaries were interpolated using topographic maps at a scale of <br />1:1,200, with a contour interval of 2 feet (Reference 4). <br /> <br />The 100- and SOO-year floodplain boundaries are shown on the Flood <br />Insurance Rate Map (Exhibit 2). On this map, the lOa-year <br />floodplain boundary corresponds to the boundary of the areas of <br />special flood hazards (Zone AE); and the SOO-year floodplain <br />boundary corresponds to the boundary of areas of moderate flood <br />hazards. In cases where the 100- and SOO-year floodplain <br />boundaries are close together, only the lOa-year floodplain <br />boundary has been shown. Small areas within the floodplain <br />boundaries may lie above the flood elevations but cannot be shown <br />due to limitations of the map scale. <br /> <br />4.2 Floodways <br /> <br />Encroachment on floodplains, such as structures and fill, reduces <br />flood-carrying capacity, increases flood heights and velocities, <br />and increases flood hazards in areas beyond the encroachment <br />itself. For purposes of the NFIP, a floodway is used as a tool to <br />assist local communities in this aspect of floodplain management. <br />Under this concept, the area of the lOa-year floodplain is divided <br />into a floodway and a floodway fringe. No floodways were computed <br />for Eureka Gulch and Gregory Gulch, <br /> <br />S,O INSURANCE APPLICATION <br /> <br />For flood insurance rating purposes, flood insurance zone designations <br />are assigned to a community based on the results of the engineering <br />analyses, These zones are as follows: <br /> <br />Zone AE <br /> <br />Zone AE is the flood insurance rate zone that corresponds to the <br />lOa-year floodplains that are determined in the Flood Insurance <br />Study by detailed methods, Whole-foot base flood elevations <br />derived from the detailed hydraulic analyses are shown at selected <br />intervals within this zone, <br /> <br />Zone X <br /> <br />Zone X is the flood insurance rate zone that corresponds to areas <br />outside the SOO-year floodplain, areas within the SOO-year <br />floodplain, areas of lOa-year flooding where average depths are <br />less than 1 foot, areas of lOa-year flooding where the contributing <br />drainage area is less than 1 square mile, and areas protected from <br />the lOa-year flood by levees, No base flood elevations or depths <br />are shown within this zone. <br /> <br />7 <br />