Question

Given a 5-ha residential watershed with 20% of the area defined as business neighborhoods, 30% single family dwellings, 10% parks, and 40% asphalt or concrete pavement, determine an average C-factor. Also given are an L of 200 m and an average slope of 0.4%. The 10-year IDF curve is:

i = 225/(t^0.61 + 4.5),        where t = min, i = mm/hr

Local drainage regulations require a design for a 10-year rainfall event and t_c greater than or equal to 5 minutes, Determine Q_P in CFS.

Answer 1