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For the streams studied by approximate methods, only the 100-year flood plain boundary is shown ion the Flood Insurance Rate Map (Exhibit 2). These boundaries were taken directly from the Flood Hazard Boundary Map (FHBM) for Teller County (Reference 16), and the Flood Insurance Rate Map ~or Cripple Creek (Reference 17). Additional approximate flood plain boundaries within Woodland Park have been determined using topographic mapping at a scale of 1:2,400, with a contour interval of 5 feet (Reference 18). 4.2 Floodways Encroachment on flood plains, ,such as structures and fill, reduces flood-carrying capacity, increases flood heights and velocities, and increases flood hazards in areas beyond the encroachment itself. One aspect of flood plain management involves balancing the economic gain from flood plain development against the resulting increase in flood hazard. For purposes of the NFIP, a floodway is used as a tool to'assist local communities in this aspect of flood plain management. Under this concept, the area of the 100-year flood plain is divided into a floodway and a floodway fringe. The floodway is the ~hannel of a stream, plus any adjacent flood plain areas, that must be kept free of encroachment so that the 100-year flood can be carried without substantial increases in flood heights. Minimum Federal standards limit such increases to 1.0 foot, provid~d that hazardous velocities are not produced. The floodways in this study are presented to local agencies as minimum standards that can be adopted directly or that can be used as a basis for additional floodway studies. The floodways presented in this study were computed for certain stream segments on the basis of equal conveyance reduction from each side of the flood plain., Floodway widths were computed at cross sections. Between cross sections, the floodway boundaries were interpolated. The results of the floodway computations are tabulated for selected cross sections (Table 3). In cases where the floodway and 100-year flood plain boundaries are either close together or collinear, only the floodway boundary is shown. Because flooding from Lovell Gulch, Point Pony, and East Fork Paint Pony is shallow in natu*e, no floodways have been computed for these streams. The area between the floodwaYiand 100-year flood plain boundaries is termed the floodway fringe. The floodway fringe encompasses the portion of the flood plain that could be completely obstructed without increasing the water-~urface elevation of the 100-year flood by more than 1.0 foot a, any point. Typical relationships between the floodway and the floodway fringe and their significance to flood plain development are shown in Figure 2. 14