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<br />Effects of Watershed Rehabilitation <br /> <br />Watershed-rehabilitation efforts utilized to help restore the Buffalo Creek burned area include: aerial and <br /> <br /> <br />ground seeding; bonded-fiber matrix; soil tilling, contour tree felling; log and strawbale check dams; and <br /> <br /> <br />untreated natural recovery (Casey Clapsaddle, USFS, written commun., 1996). Extensive efforts to <br /> <br /> <br />mechanically break up hydrophobic soils and slow water and sediment runoff began very soon after the <br /> <br /> <br />fire. Most efforts were in basins posing greatest risk to the public; Sand Draw, Spring Gulch, and <br /> <br /> <br />Shingle mill Creek. A moderate flood on June 12, 1996 (Casey Clapsaddle, USFS, written commun., <br /> <br /> <br />1996) and the severe flash flood on July 12, 1996 washed out most of the initial rehabilitation efforts. <br /> <br /> <br />Small amounts of water were applied to burned areas (simple infittration tests) in 1996 and 1997. <br /> <br /> <br />Generally, no water infittrated and small droplets of water formed indicating hydrophobic soils in 1996. <br /> <br /> <br />During the wet spring of 1997, applied water infiltrated rapidly, even on very steep hillslopes (>30 'Yo). <br /> <br /> <br />However, after the soils dried, infiltration was low due to reformed hydrophobic cond~ions or other factors. <br /> <br /> <br />Data monitoring in this study complements an instrumented, paired-basin analysis being conducted by <br /> <br /> <br />Casey Clapsaddle to assess the rehabil~ation efforts used in Shinglemill Creek and Morrison Creek <br /> <br /> <br />(burned area was left untreated). <br /> <br />Despite extensive rehabil~ation efforts in burned area, smaller rainstorms after July 12 in 1996 and 1997 <br /> <br /> <br />produced similar rates of runoff (fig. 3), which reflect persistent conditions that exacerbate flash-flood <br /> <br /> <br />potential. Natural debris (trees and sediment) present in many channels appeared to help slow water and <br /> <br /> <br />sediment runoff for many events. In add~ion, small runoff events (as much as -3 m3ts) from bumed <br /> <br /> <br />hillslopes that reached channels having thick (>3 m) pea-gravel sediments such as in Sand Draw often <br /> <br /> <br />infiltrated in a short distance. Long-time residents indicated that since the fire, streams in the bumed area <br /> <br /> <br />have more flow that usual. <br /> <br />Base flows as small as 0.2 m3/s after the July 12th flood were competent to incise and erode much of the <br /> <br />new alluvial fans, Many fans had several agradation-degradation cycles for small events (peak flows of -1- <br /> <br />12 <br />