×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Rational formula - strange resulting Qp

Rational formula - strange resulting Qp

Rational formula - strange resulting Qp

(OP)
Hi,
I'm estimating peak discharge values for two basins. One is the other's tributary. One has an area of 64 km2 and the other 0,7 km2.
For the bigger basin (Stream A) I obtain reasonable values (167 m3/s) according to other methods (SCS, Giandotti), but in the small tributary I'm getting an anormaly huge value (46 m3/s). Can someone help me find what am I doing wrong? I believe the error is related to the Rainfall Intensity because in the SCS method I obtained good discharge values (4 m3/s).
I've uploaded a small .doc file with the calculations.
Thanks and apologize my weak English.
Pedro Santos

RE: Rational formula - strange resulting Qp

first of all, your rainfall intensity for the small area looks a bit high
secondly, using rational method for a 64 square kilometers area is not appropriate and should not be done.  Suggest a better method would be to use regression equation based on similar large watersheds
thirdly, your basin may produce more runoff during a 24-hour or longer storm.   

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources