CIV E 444 - APPLIED HYDRAULICS FALL 2009 HOMEWORK No. 2 Determine the water savings, in cubic meters, during the month of May, to be accomplished by planting a wind break (a line of trees) in a farm. The farm area is 50 ha, and the wind velocity at 2-m depth is expected to be reduced from 200 km/day to 80 km/day. The mean monthly air temperature is 17oC. The mean monthly net radiation is 580 cal/cm2/day. The relative humidity is 70%. If the cost of water is $300/1000 m3, what is the savings realized? Use Penman calculator (92). Calculate the time of concentration for a basin with L = 250 m, So = 0.01, and n = 0.05, i = 25 mm/hr, using the Kirpich, Kerby-Hathaway and Papadakis-Kazan formulas. Use time of concentration calculator (120). Determine the 100-yr flood discharge for a basin located in Southern California, with the following data:   drainage area A = 8 mi2, 24-hr rainfall depth P = 3 in, [normal] curve number CN = 73, time of concentration tc = 1 hr, and percentage of pond and swamp areas = 0%. What would be the 100-yr flood discharge for a [wet] CN = 87? Use TR-55 calculator (105). A certain basin has a 1-hr unit hydrograph as follows: Hourly ordinates (cfs):     0, 100, 300, 700, 500, 300, 100, 0 Calculate the composite flood hydrograph for the following 3-hr storm rainfall: Hourly ordinates (in/hr):     1.5, 2.5, 1.0 Assume CN = 90. Use Convolution calculator (111).