CE 4200 Chapter : Exam 2 CE4200 Fall 2017
Document Summary
A watershed has a curve number of 91. For an 80-min storm with a rainfall intensity distribution below, use the nrcs curve-number method to estimate total runoff generated by this 80-min storm. A catchment area consists of silt loam, which typically has saturated hydraulic conductivity of 7 mm/hr, soil suction head of 170 mm, porosity of 0. 501, and initial soil moisture content of 0. 21. Given the following 3-hour rainfall on the area, using the green-ampt method to find ponding time. The surface of a 5-ha catchment is characterized by a runoff coefficient of 0. 64, a manning coefficient of 0. 12 for overland flow, an average overland-flow length of 60 m, and an average slope of 0. 3%. The drainage channel is to be sized for the peak runoff rate resulting from a 10- year rainfall event, and the 10-year idf curve is given by i. A direct runoff hydrograph in the table below was measured at the outlet of a 1. 2-km2 catchment.
