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places, the width of the 100-year floodplain averages over 1,000 feet, although the depth of flooding is generally less than 3 feet, except in areas where ponding occurs. Hydrologic data from stream gages were not available, thus no discharge and recurrence intervals for major floods along Cooper Slough were determined. Limited information is available regarding past flooding from Dry Creek. In 1904, a flood occurred that resulted in the drowning death of a child when floodwaters overtopped the Eaton Ditch (which intercepts Dry Creek near Willox Road. Flooding also occurred in 1924 with depths of flows several feet deep. However, it is unclear as to whether the flooding was due to overflow from the Cache La Poudre River (Reference 1). Numerous irrigation canals cross the Dry Creek channel and directly intercept drainage flows. In the past, much of the excess drainage in the lower Dry Creek basin (below Eaton Ditch) was intercepted by irrigation canals. However, the impact of development has increased the magnitude and frequency of drainage flow, and many of the canals no longer have the capacity to intercept the increased drainage flows. Several of the canals, including the Larimer and Weld Canal (Eaton Ditch), Larimer County Canal, Terry Inlet, Poudre Valley Canal, and North Poudre Ditch, have large enough flow capacities to impact flood magnitudes on Dry Creek (Reference 1). Fish Creek and the Fall River have not often been subject to major flooding, although the Fall River did overflow its banks in 1965 and cause some damage. In July 1982, extensive damage occurred throughout the Town of Estes Park because of the failure of Lawn Lake Dam located in the headwaters of the Fall River. On July 15, 1982, the Lawn Lake Dam on the Roaring River failed. According to the Rocky Mountain News, this catastrophic failure sent "a 3D-foot wall of water down Roaring River...The water swept into Fall River...At about 8 A.M., it slammed into resorts perched on the river's banks at the west end of Estes Park." The Lawn Lake Dam failure caused property damage estimated at $20 to $30 million, and the loss of several lives. The flooding from this event was more extensive than that which would be caused by the 0.2-percent annual chance flood. The Town of Estes Park has not frequently been subject to damaging flood flows however, the flood of 1965 demonstrated the potential for flooding that does exist, particularly in areas where buildings encroach upon the riverbanks. The 1965 flood, which was the most recent, was the result of a combination of heavy rain and rapid snowmelt on a warm day in June. Rainfall depth over a 2-day period was approximately 1.9 inches. The peak in the Big Thompson River near Lake Estes was approximately double the normal flow. The 1965 peak of 1,640 cubic feet per second (cfs) was the most damaging flow in recent history, although flows of this magnitude were also recorded in 1949, 1951, 1953, and 1957. Damage from the 1965 event was the result of continued encroachment upon the river channels and blockage of the Fall River culvert at Elkhom Avenue that diverted flows through the center of town. Documentation of floods on Redstone Creek is relatively sparse. However, an intense rainstorm on September 10, 1938, caused flooding in some of the lower areas of the flood plain (Reference 7). 16