CIV E 445-APPLIED HYDROLOGY
SPRING 2003
FIRST MIDTERM
TUESDAY, FEBRUARY 25, 2003, 1230-1345

Name: ______________________ S.S. No. _____________ Grade: _______

Instructions: Closed book, closed notes. Use engineering paper. When you are finished, staple your work in sequence (1 to 4), and return this sheet with your work.

  1. (20%) A 265-km2 basin has 750 mm of mean annual precipitation, and the mean annual outflow is 1.9 m3 s-1. What percentage of precipitation is abstracted by the catchment on a mean annual basis?

  2. (20%) Fit a Horton infiltration formula to the following measurements:

    Time (hr) f (mm/hr)
    1 2.75
    2 1.90
    infinity 1.50

  3. (20%) Calculate evaporation rate by the Penman method for the following atmospheric conditions: air temperature Ta = 20oC; net radiation Qn= 620 cal/cm2/day; wind speed v2 = 150 km/day; relative humidity RH= 75%.

  4. (40%) Please answer questions in a brief statement.

    1. What is the difference between hydraulics and hydrology? Be specific.
    2. What three conditions are necessary for precipitation to occur?
    3. What is the difference between potential and actual evapotranspiration?
    4. What four factors affect time of concentration?
    5. What is baseflow? Where does it come from?
    6. What is rating curve? How many types of rating curves are there?
    7. What do the Creager curves depict?
    8. To what five factors is to be attributed the recurrence of debris flows in the San Gabriel Mountains of Northeast Los Angeles? State them in causal order.