Name: _______________________ RED ID ________________________ Grade: _______

Instructions: Open book, closed notes. Use engineering paper. When you are finished, staple your work in sequence, and return this sheet with your work.

1. (PROBLEM, 30%) Given the following flows measured in the recession limb of a flood hydrograph:

   Time (hr)	0	1	2	3	4	5	6	7	8	9	10
   Flow (m3/s)	32.0	25.2	20.5	17.9	16.1	14.5	13.5	12.9	12.6	12.3	12.0

   Calculate:

   • The time of storage t_s for baseflow, from the tail of the recession;
     
   • The baseflow and quickflow components of the recession curve;
     
   • The volume released from baseflow in the elapsed 10-hr period;
     
   • The volume released from baseflow from t = 0 to t = ∞, assuming that the flow eventually recedes back to zero.
     

2. (QUESTIONS, 30%) Answer all the following questions with a brief statement:
   
   • What is Rorabaugh's contribution to hydrology?
   • Why did Woolhiser and Liggett switched their research emphasis from dynamic to kinematic wave modeling in the mid 60s?
   • What is the difference between the Clark and ModClark methods? Is the ModClark method lumped or distributed?
   • What are the four components that a catchment rainfall-runoff model must have? Does the HEC-HMS model properly account for channel routing in semiarid and arid regions? Why?
   • Why is sediment transport emphasized in sand-bed rivers instead of sediment yield?
   • What is the cause of global warming? What are the effects of global warming?

3. (ESSAY, 40%) Write a 300-word essay on either of the following topics:
   1. Argue against the NRCS runoff curve number method (following Smith).
   2. Argue against the kinematic wave numerical method (following Dr. Ponce).