CIV E 445 - APPLIED HYDROLOGY
SPRING 2014
HOMEWORK No. 11

  1. Given the following inflow hydrograph to a certain stream channel reach, calculate the outflow by the Muskingum method. Assume K = 1 h, X = 0.2, Δt = 1 h. Report peak outflow and time of occurrence. Use a spreadsheet and verify with ONLINE ROUTING 04.

    Time (h) 0 1 2 3 4 5 6 7 8 9 10 11 12 13
    Inflow (m3/s) 12 30 50 100 145 160 140 75 55 45 35 25 15 12

  2. Given the following inflow and outflow hydrographs for a certain stream channel reach, calculate the Muskingum parameters K and X.

    Time (h) 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
    Inflow (ft3/s) 2520 3870 4560 6795 8975 9320 7780 6520 5340 4105 3210 2520 2520 2520 2520 2520 2520 2520
    Outflow (ft3/s) 2520 2643 3598 4500 6367 8295 8900 7971 6808 5628 4439 3482 2782 2592 2540 2525 2521 2520

  3. A large river of nearly constant width B = 300 m is seen to be rising at the rate of 3 mm/h. At the observation point, a stage measurement indicates that the current value of discharge is 1175 m3/s. What is a rough estimate of the discharge at a point 20 km upstream?

  4. Solve the Muskingum-Cunge method of flood routing for a triangular inflow hydrograph, with routing parameters based on peak flow. Use the following data: peak discharge = 1110 m3/s, baseflow = 60 m3/s, time-to-peak = 7 h, time base = 21 h, channel bottom slope = 0.001, flow area corresponding to the peak discharge = 440 m 2, channel top width corresponding to the peak discharge = 115 m, rating exponent β = 1.58, reach length = 14 km, time interval Δt = 1 h. Report peak outflow and time-to-peak. Use a spreadsheet and verify with ONLINE ROUTING 05.