Determine the depth of runoff by the TR-55 method for a 24-hour, 100-year precipitation of 9 inches for an antecedent moisture condition III, if the following land uses and soil conditions exist.
What will be an ideal response?
Since different land uses are present, a weighted CN value must be calculated.
The CNII values can be found in Table 16.3, and the corresponding CNIII values in
Table 16.5, as shown below.
Weighted CNIII = (0.33)(93.4) + (0.27)(97.4) + (0.12)(95.8) + (0.23)(92.8) + (0.05)(97.2)
Weighted CNIII = 94.82
Determine the potential maximum retention after runoff begins, using Equation
16.7.
S = (1000 / CN) – 10
S = (1000 / 94.82) – 10
S = 0.546 in
Determine depth of runoff using Equation 16.5.
Therefore, the depth of runoff will be 8.38 inches.
You might also like to view...
Built-up roofing of felt and asphalt is used on flat or low-sloped roofs below a 3:12 pitch.
Answer the following statement true (T) or false (F)
List the advantages of a wound-rotor induction motor.
What will be an ideal response?
How is poor steering provided on hybrid electric vehicles when the engine is not running?
What will be an ideal response?
Why are some reclaimed refrigerants classified as hazardous materials?
A) They have been through sealed systems. B) They are from pre-1993 systems. C) They have been recycled before being reclaimed. D) They may contain corrosive or carcinogenic chemicals.