What is the composite C value for the following drainage area for a 10-year storm recurrence interval?Drainage area: 0.25 acres of residential lots with 40% imperviousness (C = 0.49) 0.25 acres of lawn with 0.95% slope with 0% imperviousness (C = 0.22) 0.10 acres of impervious pavement (C = 0.95)

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The composite C value for the given drainage area for a 10-year storm recurrence interval is 0.45. Solution: Calculate composite C by using the following equation: C = (C₁A ₁+ C₂A ₂+ C₃A₃) / (A ₁+ A ₂+ A₃) C = [(0.25 acres x 0.49) + (0.25 acres x 0.22) + (0.10 acres x 0.95)]/ (0.25+0.25+0.10) C = 0.45

What Is the Composite C Value for the Following Drainage