CIV E 444 - APPLIED HYDRAULICS
SPRING 2016
HOMEWORK No. 13 SOLUTION

  1. With CN = 80, run ONLINE TR-55 with Type I storm (Coastal Southern California), to determine Qp = 3,338 cfs.

    Target peak discharge = 0.8 × 3,338 = 2,670 cfs.

    Run ONLINE TR-55 again, trying smaller values of CN, say, 76 and 75.

    For CN= 76, Qp = 2,756 cfs       [Too high!]

    For CN= 75, Qp = 2,621 < 2,670

    The target CN is 75. The watershed will be improved to reduce CN from 80 to 75.

  2. Use ONLINE CHANNEL 04 to find Sc = 0.0025.

    The Darcy-Weisbach f:   f = 8 Sc = 0.02       [Roberson Chapter 4-1 Notes].