10.28. A 3-km2 catchment has an average curve number of 60, an average slope of 0.8%, and a flow length from the catchment boundary to the outlet of 1000 m. If the catchment is 40% impervious,determine the NRCS unit hydrograph for a 20-min rainfall excess. 10.34. Determine the approximate NRCS triangular unit hydrograph for the catchment described in Problem 10.28 O, and verify that it corresponds to a rainfall excess of 1 cm.

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