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WHEREAS, detailed hydrologic analyses were performed as part of the Flood Study, dated May 1986, and said detailed analyses were used for the delineation of approximate floodplains for the drainageways in said new report, as listed in Table 2 below: Table 2 Drainal!ewav Locations in the Town of Otis For Which Detailed Hvdrollll!ic Analvses Were Performed Drainageway Location Drainage Area Southwest Draina.. South Dade Street 17,46 so, mi, Southwest Drainal!e Railroad culVerts 18,42 sa, mi, Northern Draina~e North Dade Street 9,96 sa, mi, ; and Definitions of Terms WHEREAS, the Colorado Water Conservation Board staff has defined terminology pertinent to the preparation of approximate and detailed floodplain information and to proposed developmeilt activity within delineated floodplains, as described in Table 3 below: Table 3 Definitions for Preparlrll! Floodplain Information and for Rel!lllatinl! Development Proposals in Approximate Floodplains Term Definition Approximate hydrology lOO-year peak flow values estimated for the hydrologic point of interest using "Guidelines" or other accemable approximate hydrologic method approved by the CWCB Detailed hydrology lOO-year (and 10-,50-, and 500-year when applicable) peak flow values computedfor the hydrologic point of inter-est using an acceptable detailed methodology, other than the "Guidelines ", such as an at-site stream gage analysis, a regional stream gage analvsis, or a rainfall-runoff model Approximate hydraulics Water surface elevations or flow depths computed for the location or reach of interest using normal depth flow calculations (i,e, Manning's equation/slope-area method) with manual techniaues or comPuter orOPTams such as OUICK-2 and FlowMaster Detailed hydraulics Water surface elevations (bllSe flood elevations) computed for the stream reach of interest using a step-backwtzter computer model, or other acceptable one-dimensional or two dimensional comuut., model, such as HEC-2 or HEC-RAS Limited development Development involving parks, open space, golf courses, agriculture, bridges and cu/vens serving single farms or single family homes or cabins, pole bams, and individual single familv residential structures Signifreant 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 units Or more, whichever is more restrictive ; and 4