LAR 512 – Fall 2002

 

PROBLEM #5 – BASICS IN RUNOFF ESTIMATION

 

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dissertation_prob5.pdf

 

Download the above graphs and answer the following questions:

 

1.      Using the infiltration graph on page 250:

What is the final constant infiltration rate with moist antecedent moisture conditions? __________

 

2.      Using the infiltration graph on page 251:

What is the final constant infiltration rate with wet antecedent moisture conditions at the same location as above? __________

 

3.      Please explain why there is this difference? ____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

 

4.      Using the infiltration graph at top of page 257:

What is the final constant infiltration rate with moist antecedent moisture conditions? __________

 

5.      Using the infiltration graph at top of page 257:

What is the final constant infiltration rate with wet antecedent moisture conditions at the same location as above? __________

 

6.      Please explain why there is this difference? ____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

 

7.  Please explain the difference in the soil profile between the site represented by page 250/251 and 257?

____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

 

8.      Please consider a storm event that has a rainfall of the following:

 

Time   0 to 10 minutes:  intensity of 100-cm/hr

Time 10 to 30 minutes:  intensity of   60-cm/hr

Time 30 to 60 minutes:  intensity of   50-cm/hr

 

What is the total amount of rainfall? __________cm/hr __________in/hr

 

What is the total amount of infiltration for this rainfall?

 

      Using graph on page 251: ___________cm __________in

     

      Using graph bottom page 257: __________cm __________in

 

What is the total amount of runoff for this rainfall?

 

      Using graph on page 251: ___________cm __________in

     

      Using graph bottom page 257: __________cm __________in

     

9.      Why is there such a pronounced effect between the two graphs in terms of amount of infiltration and amount of runoff?

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