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. predominately flooded from local drainage in the Pioneer Ditch, and not Sand Creek. Our understanding is that Pioneer Ditch's capacity is frequently exceeded immediately upstream of the Burlington Northern Railroad and between the railroad and State Highway 14, The excess flow overtops the channel banks and continues east into town, The report also indicates that floodwaters from Sand Creek and Pioneer Ditch reside before the Pawnee Creek Overflow have historically reached Sterling. Therefore, this area remained a SFHA designated AH. The BFE's shown on the annotated map are consistent with those presented in the FPIOP report, Area C: These areas are shown by the flood boundary map in the FPIDP report as being outside of the Pawnee Creek Overflow IOO-year floodplain. The areas are within the Sand Creek and local drainage floodplain, but only from sheet flow or shallow flooding (less than I-foot), Therefore the areas have been removed from the SFHA, They do, however, remain Zone X (shaded) since shallow flooding exists and residual SOD-year flooding is anticipated from the Pawnee Creek Overflow, Sand Creek and the South Platte River, . Area D: This area is shown by the flood boundary map in the FPIDP report as being outside of the IOO-year Sand Creek and local drainage floodplain. The area has been removed from the SFHA, but remains Zone X (shaded) since residual SOD-year flooding is anticipated from the Pawnee Creek Overflow, Sand Creek and the South Platte River. Area E: These areas are depicted as Zone AE, Detailed Study, for Sand Creek in the effective FIS, These areas have not been modified, with exception to clarification of a couple ofBFE's shown in the FPIOP report, Base Flood Elevations (BFEs) BFE's have been determined in the vicinity of the Interceptor Channel. These BFE's reflect the project mapping, NGVD 1988, BFE's have also been added or modified to Areas B and E, mentioned above, These BFE's were based on the FPIDP report and remain on Datum NGVD 29, Special Flood Hazard Area (SFHA) . The SFHA has been adjusted accordingly to reflect the construction of Pawnee Creek Overflow Interceptor Channel. The historic Pawnee Creek Overflow IOO-year floodplain has been removed in the vicinity of Sterling and a new I DO-year floodplain has been established in the Interceptor channel. Therefore, a significant amount of changes to the SFHA have occurred, Structures in Sterling remain subject to potential flood hazard by the residual Pawnee Creek Overflow SOD-year floodplain, as well as floodplains associated with Sand Creek and the South Platte 7