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<br />The discharges g1ven in Table 2 represent instantaneous peak di_scharges <br /> <br />of debris 1n channels at the fronts of the flow surges. The individual <br /> <br />discharge peaks probably lasted consiclerably less than one minute, perhaps <br /> <br />only 10 to 20 seconds. The disc:hargee: of debris, although of short duration, <br /> <br />exceed flood-water discharges from the larger upper basins by a factor <br /> <br />of 3 to 5, even though the upper basins constitute 65 to 93 percent of <br /> <br />the total basin areas (Table 1).. For comparison to the debris flow discharges <br /> <br />of Table 2, water discharges were calculated at the points where the larger <br /> <br />upper basins discharge into the smaller lower basins using high water marks <br /> <br />and the Manning equation. The water discharges were only 250 to 400 cfs <br /> <br />0.1 to 11.3 m3/sec) and are approximately equal to what would be calculated <br />for these basins during a "lOa-year storm" using standard storm discharge <br /> <br />methods (such as that used presently by the Soil Conservation Service). <br /> <br />This is not meant to imply that the hydrologic methods are i.naccurate or <br /> <br />provide misleading results when applied to flood runoff. However, it does <br /> <br />suggest that the debris-discharge process, as discussed in Secti.on A of <br /> <br />this chapter, can magnify the peak discharge temporarily through damming <br /> <br />and addition of solid material. <br /> <br />Boulder transport by the debris flows was also studied in detail because <br /> <br />it gives a general indication of the destructive potential of the flows. <br /> <br />To determine quantitatively the boulder transport capabilities of the flows, <br /> <br />- 26 - <br />