×
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

French drain

French drain

French drain

(OP)
Found lots of help from recent french drain posting, but my problem is slightly different. Original grading effectively channeled hillside water flow to left and right of house. Slightly soggy in spring but not too bad. Construction activities last year apparently changed contour just enough that I get a standing water build up after prolonged rainfall. Want to french drain a 100 foot crescent, but overall the land will drop about 3-4 feet, a 0.4 inches per foot average. I am concerned that this will allow too much velocity at the discharge end of the drain and cause erosion. I can discharge onto a driveway parking area, but this also has it's downside for people trying to get to their cars. Any suggestions?

RE: French drain

Some options
1) Drain to a 4'x4' concrete splash pad, set 1" below grade, with concrete tapered to grade.
2) Drain to an endwall structure with a velocity breaker - a small 4"-6" wall that has a 4"-6" opening at one end and splash pad.
3) Drain to a bubbler - a ADS plastic catch basin that will function the opposite of normal. This will be a recurring maintenance item.  It should have an internal sump and be set atleast 1"-2" below adjacent grade.
4) Calculate your velocities and and determine what erosion protection is actually needed, if any
5) Do nothing, just repair (possibly excavate an additional 12" in all horozontal directions, except at the pipe end) the erosion with a minimum of 4" deep of fibermesh concrete, set a minimum of 1/2" below adjacent grade.  Remember, when repairing erosion, the water must be blocked from channeling under the concrete repair.

Best of Luck.......

Clifford H Laubstein
FL Certified PE #58662

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