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Illustrations Captions 1. Map of the Buffalo Creek study area showing the extent of May 18, 1996 wildfire (heavy- dashed line) and selected flood sites. Flood-site locations are: 1. Buffalo Creek at Buffalo Creek; 2. Sand Draw near Buffalo Creek; 3. Spring Creek near South Platte River; 4. South Platte River at South Platte streamflow-gaging station 06707500 (gage); and 5. South Platte River downstream from Spring Creek. Inset map at lower right shows the general location of the study area near Denver and Colorado Springs, Colorado. Twenty-four hour rainfall amounts in millimeters from bucket survey shown as "x." Isohyetal patterns for the July 12, 1996 rainstorm from the National Weather Service estimated from Doppler radar (NWS-WSR-88) showing maximum 1-hr rainfall of atleast 80 mm. .. .. .. ... 2. Map of Buffalo Creek showing rainfall-bucket survey data and isohyetal patterns for the July 12, 1996 rainstorm from paleohydrologic interpretations. Paleohydrologic rainfall estimates were made four days after the storm. 3. Photographs showing hillslope rill and gully development for 1-hr rainfall amounts for July 12, 1996 of: a.) less than about 25 mm of rain with minimal rills; b.) about 50 mm of rain produce 75 mm by 50 mm rills; c.) about 75 mm of rain produced extensive rilling and about 500 mm deep gully formation; and d.) gully development up to 1 m deep and 3 m wide, which was used to infer the area of maximum rainfall of at least 115 mm in an hour (fig. 2). 4. Maps of Buffalo Creek showing isohyetal patterns for the July 12, 1996 rainstorm using Doppler radar (NWS-WSR-88) developed by Henz (1998). Maximum 1-hr rainfall was estimated to be about 140 mm and the 24-hr rainfall was about 170 mm for July 12, 1996. 5. One-hour and 24-hr rainfall-frequency relation for Buffalo Creek developed by Diller (1997) and the 1-hr rainfall-frequency relation of Miller et al. (1973). The estimated maximum 1-hr rainfall of about 140 mm and 24-hr total rainfall of 170 mm for Buffalo Creek on July 12, 1996 (Henz, 1998) also are shown. 6. Schematic cross section with hydraulic properties for the July 12, 1996 flood in Buffalo Creek near the North Fork South Platte River at Buffalo Creek, Coiorado. 7. Upstream view of Spring Creek on July 16, 1997 with the South Platte River in the foreground (flow left to right). Flood-deposited sediments were about 1.5 m thick at the center of the fan. 8. Downstream view of Shinglemill Creek near Buffalo Creek showing a 600-mm diameter, f1ood- transported boulder lodged in a 1-m diameter cottonwood tree. The boulder is 2.5 m above the channel bed (at the tree) and about 1.5 m above the high-water marks from the July 12, 1996 flood. 9. Upstream view of Sand Draw about 1 km upstream from Buffalo Creek showing distinct black, burn boundary from the May 18,1996 wildfire. The boundary was used to define pre-fire, channel-bed levels and estimates of the amount of channel change at this flood (about 0.5 m here). 10. Relation between peak discharge and contributing drainage area for rainstorms in 1996 and 1997 in the Buffalo Creek area, Colorado. Lines show approximated 1-hour storm rainfall for burned and unburned basins. Flash-flood data for extreme rainstorms for similar, unburned basins in the Colorado Front Range foothills help assess the effects of the fire on flooding in Buffalo Creek. 11. Flood-frequency relations for pre-fire basin conditions for Sand Draw at Buffalo Creek (FEMA, 1986) and the South Platte River at South Platte (06707500) from an frequency analysis of annual peak-flow data. Peak discharges for the July 12, 1996 flood for Sand Draw and at the South Platte River at South Platte also are shown. Draft 3/30/98 .,a