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<br />the end of 1997, but hillslope erosion continues to contribute sediment to channels. Sediment
<br />from the burned area continued to be transported through the NF and South Platte Rivers to
<br />Strontia Springs Reservoir. About 75 percent of Denver's water comes through the reservoir,
<br />which has a capacity of about 9.74 hm3. From May 1996 to October 1997, about 0.31 hm3 of
<br />sediment washed into the reservoir compared to about 0.14 hrn3 in the 13 years since the
<br />reservoir was built (Denver Water Department, written commun., 1997). Snowmelt runoff in the
<br />NF and South Platte Rivers likely will continue to move large amounts of wildfire-produced
<br />sediments towards the reservoir.
<br />
<br />Geomorphic investigations of alluvial sediments in the burned and unbumed (in 1996) areas
<br />indicate at least 10 fires/flood sequences have occurred in the study area prior to 1996 (fig. 12).
<br />At least one paleoflood was larger than the July 12, 1996 flood, and runoff after several of the
<br />prehistoric fires produced much thicker alluvial deposits than following the 1996 wildfire.
<br />Radiocarbon dating of organic material in alluvial sediments in a Buffalo Creek tributary indicated
<br />that these sequences span about the last 2,500 years (John Elliott, USGS, written commun.,
<br />1997). Additional investigations will help determine the long-term fire and 1I00d history in the
<br />region, which could help forest managers develop policy for prescribed burns and other
<br />management practices.
<br />
<br />Study results can be used to develop and verify hydrologic- and sediment-budget models for
<br />burned watersheds. In conjunction with the NWS, study results and rainfall-runoff modeling was
<br />conducted to help determine threshold-rainfall amounts for lIash-flood conditions. These results
<br />were used to refine lIash-flood wamings, particularly to minimize the number of false alarms that
<br />can cause complacency of those at risk. The Colorado Water Conservation Board (1997)
<br />prepared an emergency response, hazard-mitigation, and awareness plan for government
<br />officials, residents, and visitors in the Buffalo Creek area.
<br />
<br />Studying only the Buffalo Creek area can not provide answers to all questions about wildfire
<br />hazards in other forest ecosystems. Thus, additional paleollood studies are needed for burned
<br />(wildfire and prescribed burn) watersheds this century in the Rocky Mountain region. These
<br />could include, but are not limited to, Storm King Mountain, Colorado (1994), Black Tiger in Boulder,
<br />Colorado (1988), Bandelier National Monument, New Mexico (1996), Mesa Verde National Park,
<br />Colorado (1996), Yellowstone National Park, Montana (1988), and Boise, Idaho (1959, 1996).
<br />Interdisciplinary research will provide scientific information for wildfire, forest ecosystem, and
<br />hazard managers. Because of the uncertainty of where future wildfires and floods may occur, a
<br />mobile monitoring approach as described here helps provide much of the necessary information.
<br />
<br />Acknowledgements. We greatfully appreciate information Buffalo Creek residents provided
<br />about the wildfire, subsequent flooding, and flood history of the area, particularly those residents
<br />who monitor daily precipitation.
<br />
<br />References
<br />
<br />Barnes, H.H., Jr., and Davidian, Jacob, 1978, Indirect methods, in Hershey, RW., ed.,
<br />Hydrometry--Principles and Practices: New York, John Wiley, p. 189-190.
<br />Cannon, S.H., Powers, P.S., Pihl, R.A., and Rogers, W.P., Preliminary evaluation of the fire-
<br />related debris flows on Storm King Mountain, Glenwood Springs, Colorado: USGS Open-File
<br />Report 95-508, 38 p.
<br />Colorado Water Conservation Board, 1997, Emergency response, flood hazard mitigation, and
<br />flood hazard awareness for residents of Buffalo Creek, Colorado: Department of Natural
<br />Resources, Denver, Colorado, 18 p.
<br />Diller, D., 1997, Regional storm frequency analysis and the Buffalo Creek lIood, Colorado, 1996:
<br />unpublished M.S. thesis, Department of Civil Engineering, Colorado State University, Fort
<br />Collins, Colorado, 81 p.
<br />Evenstad, N.C., and Rasely, R.C., 1995, GIS applications in the northern Wasatch Front pre-fire
<br />hazard risk assessment, Davis and Weber Counties, Utah: Utah Geological Association
<br />Publication 24, pp. 169-176.
<br />Ewing, Roy, Postfire suspended sediment from Yellowstone National Park, Wyoming: AWRA,
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