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WHEREAS, 100-year peak discharges within El Paso County for the streams listed in Table 2 were developed by the consulting firm of Montgomery Watson utilizing the latest available CWCB regional regression equations entitled "Guidelines for Determining 100-year Flood Flows for Approximate Floodplain in Colorado"; and WHEREAS, a procedure for determining hydrology information in El Paso County and the incorporated communities for the approximate floodplains as listed in Table 4 and for other approximate floodplains of reservoirs, lakes, ponds, local storm drainage areas, and overflows from irrigation ditches and canals has not been established by the CWCB; and those floodplain areas may not be designated as approximate floodplain information without a procedure for estimating 100-year peak flows, and therefore the local government should require that a detailed hydrologic and hydraulic study be performed by a professional engineer and submitted by the developer or the development proponent prior to any floodplain development in those cases; and WHEREAS, hydraulic determinations for the approximate floodplains listed in Tables 3 and 4 were prepared by FEMA using approximate hydraulic techniques approved under the Board's "Rules and Regulations for the Designation and Approval of Floodplains and of Storm or Floodwater Runoff Channels in Colorado" (2 CCR 408-1); and WHEREAS, Montgomery Watson staff identified numerous minor errors and inconsistencies during the review of said Flood Insurance Study, however there were no major problems found with the study that would inhibit CWCB designation and approval; and WHEREAS, the floodplain delineations in said Flood Insurance Study dated March 17,1997 for the stream reaches listed in Table 5 have been superseded by more current and accurate information published in a new report entitled "Flood Insurance Study, El Paso County, Colorado and Incorporated Areas" dated August 23, 1999: Table 5 Floodplain delineations in said Flood Insurance Study superseded by more current information ublished in the Au st 23, 1999 Flood Insurance Stud for El Paso Coun Calhan Main Channel: Station 0+00 to station 67+60 (1.28 stream miles) from the northern co orate limit 1995 of the Calhan u stream into uninco orated El Paso Coun . Calhan Fairground Tributary: Station 47+ 10 to station 68+ 10 (0.40 stream miles) from the confluence with Calhan main tributary upstream to the upper study limit at the fairgrounds within uninco orated El Paso Coun . Calhan East Tributary: Station 38+50 to station 72+ 15 (0.64 stream miles) from the confluence with Fairground Tributary in Calhan upstream to the upper study limit in the southern ortion of Calhan. 6