Retaining wall drainage ques.

Discussion in 'Hardscaping' started by sven1277, Feb 18, 2009.

  1. sven1277

    sven1277 LawnSite Senior Member
    Messages: 681

    Would you ever run a down spout into the drainage pipe behind a wall and daylight at the end?

    Generally, I would never do this but the situation is this. Retaining wall proposed to run down left side of driveway off house foundation. Driveway slopes down from house and pitches to the right, opposite the wall side. There are 2 down spouts that exit on driveway where the wall is to start. Often, runoff water crosses the drive and freezes at night. I recommended cutting the driveway and burying drainage pipe, then patching the drive. The driveway is a couple years old and the homeowner isn't keen on the patch. I don't blame them. I wish the paving company that did the drive had a little forthought to bury the pipe during the job.
  2. soopa

    soopa LawnSite Member
    from NY
    Messages: 132

    You want to drain a down spout into a perforated pipe behind your wall? Please don't.
  3. Bru75

    Bru75 LawnSite Senior Member
    Messages: 582

    Yeah, run the water anywhere else - never behind your wall. You could run the downspout in a seperate solid pipe behind the wall, but that would make me uneasy too.
  4. limaint

    limaint LawnSite Member
    from NY NY
    Messages: 98

    Run it in its own pipe away from wall...
  5. BrandonV

    BrandonV LawnSite Platinum Member
    Messages: 4,629

    ditto or get someone to bore under the drive if possible and continue on with your original plan.
  6. LB1234

    LB1234 LawnSite Gold Member
    Messages: 3,208

    Use solid SCH40 PVC pipe. I woudn't worry one bit IF the only purpose of this pipe was the downspout with nothing else connected to it.
  7. Isobel

    Isobel LawnSite Senior Member
    Messages: 548

    I wouldn't run the downspout into a perf pipe. if you had no other place I would put a solid pipe in behind the wall to carry that water--but only if the exit point was guaranteed not to backup into the perf pipe for the wall drain.
  8. PlatinumLandCon

    PlatinumLandCon LawnSite Bronze Member
    Messages: 1,315

    I've run solid pipes above the perf pipe before if a downspout has no where to go. MAKE SURE the solid pipe is water tight until its in front of the wall face, otherwise you got major issues. Thats quite a bit of water behind the wall if it leaks out.
  9. sven1277

    sven1277 LawnSite Senior Member
    Messages: 681

    Thanks for the replies. Running a second pipe might be an option if they really don't want the water across the drive.
  10. Dreams To Designs

    Dreams To Designs LawnSite Bronze Member
    Messages: 1,406

    What surface is the driveway? Can you cut a trench, and repair with a paver or brick strip, to add interest and have a reason for the patch. Maybe add an apron and/or a border course.

    Definitely don't run the down spout into the wall drain, but an additional, solid pipe added in the stone backfill should not present a problem. Run it as far away from the wall as is practical, if going to daylight. You should also consider running the downspout down on to a catch basin, before entering the pipe behind the wall or under the driveway. The grate will screen any large debris that comes off the room, but the basin section will catch most smaller material. A basin also gives you an access point for maintenance and monitoring.


Share This Page