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. . . 2 From Sheridan Parkwav upstream to South 124th Street: . Detention Pond C, with a surface area of approximately 3,0 acres, just upstream of Sheridan Parkway . A grouted riprap drop structure from approximately 880 feet upstream to approximately 990 feet upstream of Sheridan Parkway . Detention Pond E, with a surface area of approximately 1.3 acres, from approximately 1,000 feet upstream to approximately 1,500 feet upstream of Sheridan Parkway . Approximately 300 feet of8-foot by 6-foot box culvert from approximately 1,500 feet upstream to approximately 1,800 feet upstream of Sheridan Parkway . A grouted riprap drop structure from approximately 1,860 feet upstream to approximately 1,970 feet upstream of Sheridan Parkway . Detention Pond B, with a surface area of approximately 0.8 acres, from approximately 1,950 feet upstream to approximately 2,350 feet upstream of Sheridan Parkway . Approximately 650 feet of 60-inch-diameter RCP from approximately 500 feet downstream to approximately ISO feet upstream of South 124th Street . A 4-foot by 4-foot box inlet approximately 50 feet downstream of South 124th Street From South 124th Street upstream: . Country Estates Pond, with a surface area of approximately 1.8 acres, just upstream of South I 24th Street Along Tributary D, the proposed project will include channelization from the confluence with Quail Creek to approximately 50 feet downstream of South 124th Street. Because the proposed revision will also affect the unincorporated areas of Boulder and Adams Counties, separate CLOMRs for those communities were issued on the same date as this CLOMR. We reviewed the submitted data and the data used to prepare the effective FIRM for your community and determined that the proposed project meets the minimum floodplain management criteria of the NFIP. The submitted existing conditions HEC-RAS hydraulic computer models for Quail Creek and Tributary D, both dated November 2, 2000, based on updated topographic information, were used as the base conditions models in our review of the proposed conditions models for this CLOMR request. We believe that, if the proposed project is constructed as shown on the topographic work maps included in the report entitled "Aspen Creek Phase I Regional Drainage Facilities Construction Plans," prepared by Rocky Mountain Consultants, Inc., dated April 2000, and the data listed below are received, a revision to the FIRM would be warranted. The submitted existing conditions hydraulic analyses established water-surface elevations (WSELs) associated with the base flood along both Quail Creek and Tributary D. The base flood discharge values used in the existing conditions hydraulic analyses were based on UDSWM2 model results from the aforementioned FHAD study, However, base flood discharge value results from a new UDSWM2 model, dated August 22, 2000, that incorporated current land uses and the proposed development associated with the Aspen Creek project were used in the proposed conditions hydraulic analyses, The submitted proposed conditions HEC-RAS hydraulic model, dated September 12,2000, incorporated the aforementioned proposed project along Quail Creek. As a result of the proposed project, the base flood WSELs for Quail Creek within the City of Broomfield will increase and decrease compared to the existing conditions base flood WSELs. The maximum increase in base flood WSEL, approximately 2 feet, will occur approximately 1,050 feet downstream of South 124th Street, The maximum decrease in base flood WSEL, approximately 4 feet, will occur just upstream of Sheridan Parkway. As a result of