CIV E 445 - APPLIED HYDROLOGY
SPRING 2014
LAB No. 10

  1. Using ONLINEROUTING01, study the sensitivity of the outflow hydrograph to the chosen value of storage constant K. Use the following inflow hydrograph:

    Time (h) 0 1 2 3 4 5 6 7 8 9 10 11 12
    Inflow (m3/s) 0 10 30 50 80 100 90 60 40 30 20 10 0

    Assume Δt = 1 hr, and baseflow = 0. Report calculated peak outflow and time-to-peak for: (a) K = 1 hr; (b) K = 2 hr; (c) K = 3 hr; (d) K = 4 hr; (e) K = 5 hr; (f) K = 6 hr; and (g) K = 12 hr.

    Comment on the results obtained.

  2. Using ONLINEROUTING03, determine the available freeboard for the following dam, reservoir, and flood conditions: dam crest elevation = 125 m; emergency spillway crest elevation = 120 m; coefficient of spillway rating = 1.7; exponent of spillway rating = 1.5; width of emergency spillway (rectangular cross section) = 18 m.

    Elevation (m) 120 121 122 123 124 125
    Storage (hm3) 3.00 3.05 3.15 3.35 3.75 4.25

    Design inflow hydrograph to reservoir:

    Time (h) 0 1 2 3 4 5 6 7 8 9 10
    Inflow (m3/s) 0 10 15 30 55 85 105 125 150 135 110

    Time (h) 11 1213 14 15 16 17 18 19 20 21
    Inflow (m3/s) 95 72 55 38 29 14 9 7 2 1 0

  3. In Problem 2, what would be the available freeboard is the width of the emergency spillway is reduced to 16 m?