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Table 4 Definitions for Preparine Floodplain Information and for Ree:ulatine Developmelllt Proposals in Ap{)roximate Floodplains lOO-year peakjlow values estimatedfor the hydrologic point of interest using "Guidelines" or other acceptable approximate hydrologic method approved by the CWCB Detailed hydrology lOO-year (and lO-, 50-, and 500-year when applicable) peakjlow values computedfor the hydrologic point of interest using an acceptable detailed methodology, other than the "Guidelines", such as an at-site stream gage analysis, a regional stream gage analysis, or a rainfall-runoff model Approximate hydraulics Water surface elevatiom or jlow depths computed for the location or reach of interest using normal depthjlow calculations (i.e. Manning's equation/slope-area method) with manual techniques or computer programs such as QUICK-2 and FlowMaster Detailed hydraulics Water surface elevations (base flood elevations) computed for the stream reach of interest using a step-backwater computer model, or other acceptable one-dimensional or two dimensional computer model, such as HEC-2 or HEC-RAS Limited development Development involving parks, open space, golf courses, agriculture, bridges and culverts serving single farms or single family homes or cabins, pole barns, and individual single family residential structures Significant development All development that does not fall under one of the categories listed under the definition of 'Limited Development', including the special case of development that involves 5 acres or more or 50 unit.~ or more, whichever is more restrictive Need for a Case-by-Case Review of Development Proposals WHEREAS, the designation and approval by the Colorado Water Conservation Board of the approximate floodplain information for drainageways listed in Table 2 above is contingent upon the understanding by the Town ofK.iowa of the need for a case-by-case review by the Town ofK.iowa of all development proposals within those approximate floodplains listed in Table 2, with the specific understanding that the need for approximate or detailed hydrologic and hydraulic analyses will be determined in accordance with the information provided in Table 5 below; and Table 5 HYdroloeic and Hydraulic Reauirements For Development Proposals in Approximate Floodplains Limited development Limited development Significant development Significant development Within "Guidelines" limits Outside "G'uidelines" limits Within "Guidelines" limits Outside "G'uidelines" limits Approximate Detailed Detailed Detailed Approximate Approximate Detailed Detailed 5