Name: ____________________ Red ID _____________________ 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 hydraulically wide channel is operating at Froude number F = 0.35. The unit-width discharge is q = 2.5 m²s^-1. What is Lagrange's relative celerity? What are two Langrange absolute celerities (upstream and downstream)?

2. (20%) You are observing the rising flood stage of a major river. At your observation point, at a certain time the discharge is 190 m³ s^-1, and the stage is rising at the rate of 8 mm hr^-1. At a point located 11 km upstream of your observation point, the stage is rising at the rate of 12 mm hr^-1. The surface width of the river at this point, and for several kilometers upstream, is 85 m. What is your estimate of the present discharge at the upstream point 11 km upstream?

3. (40%) Please answer each question in one clear and concise paragraph:
   • What is the rationale for the labyrinth spillway? When does it cease to work as intended?

   • Compare kinematic, diffusion, dynamic, and inertia-pressure waves in terms of their celerities and diffusivities. Put in tabular form.

   • Under Chezy friction in wide channels, at what Froude number do kinematic, diffusion and dynamic wave coalesce?

   • What is the difference between a kinematic and a dynamic rating curve?

   • Under what conditions is a wave likely to be dynamic? Give an example.

   • What was Seddon's contribution to open-channel hydraulics? What year did he publish his paper?

   • What is the difference between sediment production and sediment yield?

   • What is the difference between sediment transport and sediment routing?

4. (20%) Write a 300-word essay on HEC-RAS. Note history, objectives, equations, procedures, and applications. Please consider writing style, grammar and spelling.