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. . . Community Response to the CWCB Desienation and Approval Process A letter from the CWCB was transmitted to the Town of Rye regarding the Board's proposed action for designation and approval of this Floodplain Information Report and the Rye FHBM. The letter was followed by repeated, unanswered phone calls to the Town Clerk and Mayor's private residences. On Saturday, April 20, 1996, the Town Clerk was finaly contacted at home. She indicated that the CWCB's request would be passed on to the Mayor. As of the completion of this report, no town official had contacted the CWCB. ENGINEERING METHODS Hvdroloeic Analvsis Hydrology information for the streams with approximate floodplain delineations on Rye's FHBM has been estimated in accordance with the CWCB's "Guidelines for Determining 100-Year Flood Flows for Approximate Floodplains" (Guidelines). The 100-year flow for the streams with approximate floodplains can be estimated by utilizing the regression equation for Arkansas River Basin, subregion Ark-3. The equation is Q,oo = 1,089.27(A)o,63s, where Q,oo is the 100-year peak flow in cubic feet per second, and A is the upstream (contributing) drainage area in square miles. The regression equation is only valid for tributary streams having drainage areas between 1 square mile and 930 square miles. This equation is valid for Greenhorn Creek A procedure for determining hydrology information for approximate floodplains of lakes, ponds, and local drainages has not been established. The hydrologic methodology developed in the Guidelines is appropriate for designation and approval of approximate floodplain information and for use in simple floodplain analyses for development such as open space, agriculture, farm bridges, pole barns, and individual single residential structures. The methodology is not appropriate for development involving residential subdivisions greater than 50 lots or occurring on sites greater than 5 acres, commercial construction, industrial construction, construction of public transportation facilities, or construction of flood control facilities. Table 1 displays the 100-year peak flows for Greenhorn Creek at the upstream and downstream town limits.