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<br />the 0.5 ft f100dway on the revised portions of the map. The City of Boulder does have local <br />regulations that support the 0.5 ft f1oodway. <br /> <br />I have attached a screen capture of the Boulder County Preliminary DFIRM for reference. Please <br />note that areas in the County are shaded and the areas in the City are unshaded. <br /> <br />One problem we run into with the City of Boulder LOMRs is that the revised areas will include the <br />City of Boulder and Boulder County. Boulder County is a 1 foot rise f100dway community - not a <br />0.5 foot. We ran into a similar situation in The City of Fort Collins/Larimer County recently on the <br />Poudre River. The Poudre River f1oodway, in the vicinity of Fort Collins, crosses through the City <br />and the County numerous times and in some areas straddles the border. The City wanted to map <br />a more restrictive f100dway (0.1 ft) than the 1 ft that is currently on the effective FIRM, but the <br />County did not have the regulations to support a 0.1 ft f100dway and were not in a position to <br />support it. In the Fort Collins/Larimer county case, it was decided that the more restrictive <br />f100dway would not be included on the FIRM, because of the complexities with the corporate <br />boundaries, and the varying f100dway criteria between the communities. <br /> <br />This case is slightly different in that Boulder County would support the 0.5 ft f100dway being <br />included on the FIRM, but they do not have the regulations to support it. The City also mentioned <br />that the areas that are currently Boulder County would soon be annexed by the City. <br /> <br />In the original discussion that Kevin L. and I had, we concluded that: <br />If a community has adopted more restrictive floodway standards, and <br />If the communities floodway standards are supported by the state (which they would be with <br />the new State Regs) <br />Then we would include more restrictive floodways on the FIRMs <br />We never discussed what can be mapped in areas that go in and out of communities with <br />differing local regulations. Do we default to the 1 foot in these cases? Can the City of Boulder <br />map the 0.5 foot in their case? <br /> <br />Please let me know your thoughts. <br /> <br />If you would like additional information, please feel free to contact me. <br /> <br />Thanks <br /> <br />Kevin Doyle <br />Michael Baker Jr., Inc. <br />355 Union Blvd., Suite 200 <br />Lakewood, CO 80228 <br />720.514.1102 <br /> <br />Fourmile Canyon Creek floodway was defined using a criteria requiring a maximum of <br />one-half (112') foot rise. The floodway used Method 1. The HEC-RAS model used to <br />develop the floodway is presented in Appendix 3, and the floodway mapped in plan view <br />is shown on the Work Maps in Appendix 5. The steep gradient of the channel combined <br />with numerous structures results in a zero rise at many locations in the floodway model. <br /> <br />-19- <br />