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approximately 35,300-cfs. The flood breached the levee and inundated the town <br /> by depths up to 6-feet [Floodplain Information Report, Town of Granada, Prowers <br /> County, Colorado, Colorado Water Conservation Board, 1994]. A new levee <br /> system was constructed in 1980 by the U.S. Army Corps of Engineers <br /> (USACOE). <br /> Wild Horse Creek historically drained through the center of the Town of Holly. <br /> In the 1950's, Wild Horse Creek was relocated along the western perimeter of the <br /> town and the historic channel was filled in. A levee system was constructed in the <br /> 1980s by the U.S. Army Engineer's (USACOE), Albuquerque District, along the <br /> east bank of Wild Horse Creek and the north bank of Arkansas River. The levee <br /> protects against flooding from both the Arkansas River and Wild Horse Creek. <br /> The original design capacity for the levee system was 160,000-cfs for the <br /> Arkansas River and 62,000-cfs for Wild Horse Creek. The levee system <br /> constructed by the USACOE included two closure structures along the bank of <br /> Wild Horse Creek. The closure structures occur at the levee intersections with <br /> U.S. Highway 50 (US50) and the Atchison Topeka & Santa Fe (AT&SF) <br /> Railroad. Both closure systems consist of manually installed stop logs and sand <br /> bags. Other miscellaneous closure systems for interior drainage also exist within <br /> the levee. <br /> Willow Creek historically drained in a northerly direction along the eastern edge <br /> of the City of Lamar. At some point in the 1970's, Willow Creek was relocated <br /> along an easterly course generally parallel to Highway 50. The relocation <br /> included construction of a levee as well as lowering of the channel invert. In the <br /> past, the channel has been dredged to protect the city from frequent flooding. The <br /> relocation moved the confluence of Willow Creek and the Arkansas River <br /> approximately 3.4 miles east(downstream) of the historic tie-in. <br /> Another earthen levee was constructed in the Town of Granada, along the east <br /> bank of Wolf Creek. This project was completed in 1980 by the US Army Corps <br /> of Engineers (USACOE) and supported a previous realignment of Wolf Creek <br /> from its original path through the center of Granada to the west side of town. <br /> Neither the Granada nor the Lamar levee has freeboard adequate in all locations <br /> to be certified as providing flood protection. Therefore, FEMA's "levee seclusion <br /> method" has been implemented in order to update the flood hazard information on <br /> the riverward side of the levees, while maintaining the effective flood hazard <br /> information on the landward side. It is expected that a more permanent mapping <br /> solution will be determined by FEMA. Additionally, modifications to the levees <br /> may be made so that they can be certified. <br /> 3.0 ENGINEERING METHODS <br /> For the flooding sources studied in detail in this community, standard hydrologic, and <br /> hydraulic study methods were used to determine the flood hazard data required for this <br /> 6 <br />