CIV E 445-APPLIED HYDROLOGY
SPRING 2005
FIRST MIDTERM
MONDAY, FEBRUARY 28, 2005, 1400-1515

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 420-km2 basin has 375 mm of mean annual precipitation, and the mean annual outflow is 1.4 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 3.5
    2 2.1
    infinity 1.2

  3. (20%) Calculate evaporation rate by the Penman method for the following atmospheric conditions:

    air temperature Ta = 15oC; net radiation Qn= 600 cal/cm2/day; wind speed v2 = 150 km/day; relative humidity RH= 70%.

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

    1. What four types of mathematical models are used in hydrology?
    2. What four types of lifting cause the cooling of air masses enough to produce precipitation?
    3. What is the Bowen ratio?
    4. How are the Dalton, Penman, and Penman-Monteith evaporation equations related?
    5. What is a gully?
    6. What do the Creager curves depict?
    7. What is the difference between an evapotranspirometer and a lysimeter?
    8. To what five factors is to be attributed the recurrence of debris flows in the San Gabriel Mountains of Northeast Los Angeles?