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<br />homes within a montane forest (predominantly lodgepole and ponderosa pine, douglas fir, and aspen). <br /> <br /> <br />Topography is rugged and soils are shallow, moderately well drained, and composed of coarse sandy <br /> <br /> <br />gravel (Colorado Water Conservation Board, 1997). Bedrock on average is about 1 m below ground, but <br /> <br /> <br />is exposed on many steeper hillslopes. Accumulation of organic litter (duff) on unburned forested areas <br /> <br /> <br />averages about 60 mm. The climate is serniarid and mean annual precipitation is about 400 mm, much of <br /> <br /> <br />which falls as snow from about October through April. Many streams are ephemeral in the study area and <br /> <br /> <br />flow into Buffalo Creek and the NF South Platte and South Platte Rivers, which primarily are fed by metting <br /> <br /> <br />snowpack. Flood flows in the vicinity of Buffalo Creek can resutt from flash flooding from intense, localized <br /> <br /> <br />thunderstorms, generalized rainstorms, and spring snowmett (Jarrett, 1990). Long-time residents <br /> <br /> <br />reported no significant flooding in the Buffalo Creek area in at least 70 years. The 1996 wildfire, driven by <br /> <br /> <br />strong winds, burned most vegetation and produced hydrophobic soils in much of the burned area <br /> <br /> <br />making the area more susceptible to flooding (Colorado Water Conservation Board, 1997). <br /> <br />Methods <br /> <br />No systematic precipitation, streamflow, and sediment monitoring networks existed in Buffalo Creek prior <br /> <br /> <br />to the wildfire. In April 1997, four recording precipitation and three streamflow gages were placed in <br /> <br /> <br />Buffalo, Morrison, and Spring Creek basins by the USGS in cooperation with the Denver Water <br /> <br /> <br />Department (John Moody, USGS, written commun., 1997). The NWS provided 13 Buffalo Creek <br /> <br /> <br />residents with non-recording precipitation gages to assess the spatial variability of rainfall, monitor flood <br /> <br /> <br />potential, and assess/refine rainfall estimates from Doppler radar (NWS-WSR-88). Few raingages are <br /> <br /> <br />located in the burned area, therefore, a basin-wide monitoring approach was undertaken to document <br /> <br /> <br />each runoff event. Data collection consists of determining rainfall, peak flow, and sedimentologic data for <br /> <br /> <br />most streams in the Buffalo Creek area. In 1996, rainfall-bucket survey data were obtained in areas <br /> <br /> <br />outside of the burned area (fig. 1) for each rainstonn. In addition, paleoflood and sedimentologic data <br /> <br /> <br />were used to estimate rainfall amounts and spatial variability. <br /> <br />Paleoflood hydrology is the study of flood-transported sediments and botanic information from past floods <br /> <br />6 <br />