×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Contact US

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!

*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

Modified Rational Method-routing

Modified Rational Method-routing

Modified Rational Method-routing

(OP)
What is the largest watershed that the modified rational method can handle for detention pond design? Where can I find documentation on this watershed size?

I have noticed alot of people using a rectangle hydrograph storage method for their pond routing. This would mean that the release rate from the pond is at the peak runoff throughout the storm event. Using this method gives a very small storage requirement. I feel that this method is wrong. PLease advise.

Thanks for your time.

RE: Modified Rational Method-routing

Opinions vary on the maximum watershed size for use of the Rational Method.  FEMA allows its use on watersheds as large as 1 square mile (640 ac) but most others limit its use to far smaller areas.

The Modified Rational Method for sizing detention storage is widely used but you will find it nearly impossible to find documentation for it or a convincing explanation of its validity. Many agencies use it but HARDLY ANY BELIEVE IT. Personally, I consider it BOGUS.

good luck

RE: Modified Rational Method-routing

The following thread discusses the application / mis-application of rational method to detention pond design...

thread194-120607

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! Already a Member? Login


Resources

Low-Volume Rapid Injection Molding With 3D Printed Molds
Learn methods and guidelines for using stereolithography (SLA) 3D printed molds in the injection molding process to lower costs and lead time. Discover how this hybrid manufacturing process enables on-demand mold fabrication to quickly produce small batches of thermoplastic parts. Download Now
Design for Additive Manufacturing (DfAM)
Examine how the principles of DfAM upend many of the long-standing rules around manufacturability - allowing engineers and designers to place a part’s function at the center of their design considerations. Download Now
Taking Control of Engineering Documents
This ebook covers tips for creating and managing workflows, security best practices and protection of intellectual property, Cloud vs. on-premise software solutions, CAD file management, compliance, and more. Download Now

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close