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2, The two different delineations serve two different purposes, The "existing conditions" floodplain delineation depicts areas where the purchase of flood insurance is mandatory, The "future conditions" floodplain delineation guides land use planning and the design and implementation of flood protection facilities, as depicted in a watershed master plan. . Current CWCB Position. as EXDressed in Rules and Rel!lllations for Desil!llation of FloodDlain Studies Rule 5,BJ. (Drainage Basin Conditions) of the Board's December II, 1987 Rules and Regulations for the Designation and Approval of Floodplains and of Storm or Floodwater Runoff Channels in Colorado states: "The hydrologic analysis shall be based on drainage basin conditions that will exist in the community at least 12 months following completion of the report... " The document then addresses the subject of watershed urbanization by going on to state ".,.except if fUture urbanization of a basin is likely to occur, the hydrologic analysis shall be based on foreseeable development in the basin. " Rule 4. (Definitions) states: "]7, 'Foreseeable development' means the potential fUture development oj or changes in, the land uses that are likely to take place during the period of time covered by a community's adopted master land use plan, or over a 20-year period, whichever is longer, " . Clearly the Board has gone on record as directing that those floodplain studies that are to be designated and approved by the Board must consider the likelihood of future urbanization in the watershed, The Board has also said that in those cases where such urbanization is "likely", floodplain studies must take "foreseeable development" specifically into account in the preparation of hydrologic analyses, While the Board has directed that future urbanization must be considered in studying urbanizing watersheds, it has not, however, stated a clear position on designating two separate sets of floodplain delineations for the same stream reaches, even if the intent is to meet two different purposes. As was expressed above, "existing conditions" analyses are performed for flood insurance purposes, These documents are produced as part of a nationwide, federal program, They are legal documents used by local officials, appraisers, lenders, realtors, and property owners. However, because they do not take the future urbanization of watersheds into account, they are not the best documents for the purpose of floodplain management, land use planning, and flood control master planning. The two different purposes (floodplain management vs, flood insurance) call for two different analyses, a notion not addressed by the Rules and Regulations. Tbis particular set of proposed Board actions is, therefore, asking the Board to act beyond the explicit language included in the Rules and Regulations, .