Question

Design a trapezoidal channel that is capable of conveying 45 cfs from an elevation of 5000 feet to an elevation of 4500 feet. The total length from one point to another is 15 miles. The channel is to be rough concrete lined (n = 0.02). Try to minimize the amount of excavation required for the channel. If excavation costs are $5/cubic yard, determine the excavation costs. You should try to find the most efficient channel section. Use the area of the channel to determine the excavation costs. Keep at least 0.5 feet of free board for your channel. (i.e. The water depth should be 0.5 feet less than the channel height.) Note: this problem means that you will have to figure out what the most efficient cross section is.  

Answer 1

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