CE 4200 : Exam 1 Solution CE4200 Fall 2013
Document Summary
Exam 1 solution (4 problems, 100 points) (1) pt. A 2500 mi2 drainage basin receives 25 in/year rainfall. The discharge of the river at the basin outlet is measured at an average of 650 ft3/sec. Assume that the change in storage and seepage to groundwater for the system are essentially zero. Estimate the evapotranspiration (et) losses for the area in inches for the year. (1mi = 5280 feet, 1 ft = 12 inches, 1 year = 365 days) The idf curve for 10-year storms in los angeles, california, is given by i. 0. 51 t d where i is the average rainfall intensity in mm/hr and dt is the duration in minutes. Determine time to peak (min) and peak intensity (mm/hr) for the triangular hyetograph, where the mean of the rainfall distribution is equal to 45% of the rainfall duration. 3 t t p d (3) pi i . Solution: (1) thiessen polygon: the nearest point is rain gage b.
