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SECTIONTWO Program Plan <br />the creation of solely digital floodplain maps in the future. CWCB believes that occasional <br />needs for paper maps can be met through "print-on-demand" technology. <br />The CWCB strives to create countywide mapping in the NAVD 1988 vertical datum, NAD 83 <br />horizontal datum, and Universe Transverse Mercator proj ection for the sake of statewide <br />consistency, however it is recognized that available local data or local desire may make the <br />conversion from one datum or projection to another infeasible. Those issues can , therefore be <br />addressed during the scoping process as they arise. <br />2.1.4.1 Topographic and Base Mapping <br />Topographic and base mapping are the foundation components of any flood map update. The <br />CWCB is committed to utilizing base map information from available sources that meet FEMA <br />specifications. The CWCB prefers to use local vector GIS as the source for DFIRM creation, <br />however in areas where a local GIS is not available the U. S.G. S. Digital Orthophoto Quarter <br />Quads (DOQQ's) can be used. For topographic mapping, the CWCB will use locally available <br />or locally developed topographic mapping. The required level of topographic mapping will be <br />study- specific; however the CWCB encourages the use of topographic data that meets the <br />State's Drainage Criteria Manual. Topographic mapping that does not meet the state's minimum <br />standards will be evaluated on a study-by-study basis to determine if the use of such data would <br />be an improvement to the data that is currently represented on the effective FIRM, and is <br />accurate enough to be defensible. Topographic data that is developed by the CWCB for a flood <br />study will be generated by the Study Contractor according to the terms of their contract, or will <br />be developed by the local communities in coordination with the CWCB and with possible <br />financial assistance from FEMAThe CWCB feels that up-to-date and accurate base and <br />topographic mapping are extremely important in the flood mapping process and FEMA is hereby <br />requested to consider the funding or partial funding of such activities in the future. <br />2.1.4.2 Countywide Mapping <br />After studies are identified for countywide mapping in a particular fiscal year, a Scoping <br />Meeting will be held and a Site Specific Needs Assessment will be performed in each selected <br />county. Utilizing data gathered prior to and during Initial Coordination Meetings, the identified <br />needs will be incorporated into the countywide mapping effort to the extent possible based upon <br />available funding. Site-specific needs that are identified but which cannot be addressed due to a <br />lack of funding will be documented according to the Site Specific Needs Assessment procedures <br />outlined in Appendix A. <br />Once the scope for a countywide mapping effort has been completed, the selected engineering <br />consultant will, in addition to the standard DFIRM tasks associated with the map update for the <br />selected county, generate planimetric information and base topography and conduct hydrologic <br />and hydraulic analysis and mapping as needed based upon the scope of the study and terms of <br />their contract. In addition, the engineering consultant will update non-revised areas, either using <br />available topography, a Limited Method analysis, or digitization of effective flood hazards based <br />upon the scope of the study and terms of their contract. The CWCB recognizes the varying level <br />of effort to update flood hazards and the varying level of accuracy of each one of them. <br />Colorado Business Case Plan (Final Draft) 2-6 <br />