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

Groundwater drawdown in swale?

Groundwater drawdown in swale?

Groundwater drawdown in swale?

Hello all,

I have been asked to estimate the extent of groundwater level drawdown for a proposed swale (2' deep) that extends through a wetland (presumed groundwater elevation 6" below grade). The regulator is asking for an area around the swale that will have a lowered water table elevation due to this feature.

I haven't found a set of equations that match my needs exactly, I have seen the Theis equation that determines the cone of depression for a water well, and thought my case could be approximated by this condition.

Has anyone else had experience in answering this question?


- smm

RE: Groundwater drawdown in swale?

Consider boundary condition shown on page 4-2


There's a parameter "L," which you can estimate using page 4-24. Please note that permeability on the equation of 4-24 is in units of 10-4 cm/sec.

The length of zero drawdown is a function of permeability. Get some grain-size data (or run a field test to evaluate). If using grain-size data, here's something that may help:


Please note on the graph that permeability is also shown in units of 10-4 cm/sec.

You may want to consider all flow-to-slot equations if 4-2 doesn't quite work. That reference is a great document.


¡papá gordo ain’t no madre flaca!

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


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