Finding the end of an exterior drain

Discussion in 'Drain Cleaning' started by WV Bob, Aug 11, 2014.

  1. WV Bob

    WV Bob New Member

    Messages:
    18
    Location:
    Huntington, WV
    Not sure if this is the right place for this, but since it deals with an exterior drain I thought I'd try.

    I've got a trench across the front of a driveway that won't drain. It's about 20 feet wide, 12" deep, and 9" wide. We dug it up (6' deep!) and straightened it up some at the house, but we can't find the other end of it. It has a small 3" drain exit, and that goes into a 4" pipe along with a downspout. There's a standpipe on the drain, so when it backs up I can see it's not just the 3" exit that's causing the backup because the whole 4" pipe fills up.

    With a hose running in the pipe we can't find water coming out anywhere out in the yard. When it rains HARD the drain backs up full and eventually ends up flooding the basement via a storm drain plumbed into the same drainage run. We have a 5k GPH pump sitting in the trench now to try to prevent that, but I really need to figure the drain itself out because obviously a pump does no good if the power's out or the float sticks and you're not paying attention.

    I'm kind of skeptical that the property has enough drop to it for the drain to come to daylight so the drain may end in a dry well. So if there's a downpour, the well is filling up from the ground water so the pipe cannot drain and it backs up. But I haven't used a transit to check the lay of the land, so it could just be it takes a heckuva lot of water to fill the pipe before it backs up. I left a hose running in it for 30 minutes, and according to my math that should've been plenty to fill a 4" pipe up 100 feet long, which is about the distance to the road, but there was no water backing up at all. Of course a storm will dump that much water in minutes so maybe that's the difference.

    I'm trying to figure out if there is a way to find the end of the drain to try and figure out what could be wrong, and probably to snake it from that end. Would a plumber have anything that they could find the end with? I guess I could try dowsing it, but the water and sewer run near the problem pipe so even if a dowser could find water, it might not be the right pipe anyway. Any advice is appreciated.
  2. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    27,272
    Location:
    Cave Creek, Arizona
    Dowser? Why not just toss chicken bones? Any pipe locating company can slide their transmitter down the pipe and trace where it goes with a receiving wand. When it cannot go any further, that is either the location of a stoppage or the end of the pipe.
  3. WV Bob

    WV Bob New Member

    Messages:
    18
    Location:
    Huntington, WV
    Sorry for the slow reply HJ, I didn't get an email for your response.

    Anyway, I agree on the dowser but there's always someone who will suggest it and say it works ...

    I found one place here that would come out for a drain where I don't know where both ends are. So I called them out and after two trips I didn't learn a thing I didn't already know. This is just a tough problem and it's time to give up on unblocking the drain and start getting results, meaning abandon that pipe and just start over.

    So now I need to figure out if I can even get to daylight on the property. I'm going to give it a shot today with a length of mason's string and a line level, after it dries up some and if the rain holds off. Local news says we got 2" of rain in an hour yesterday, but it sure seemed like more to me after three and a half hours of pushing and vacuuming water last night.
  4. Terry

    Terry Administrator Staff Member

    Messages:
    15,423
    Location:
    Bothell, Washington


    Most untility crews have a witching rod that is used before the start in with the backhoe.
    You can also make them from coat hangers. It's works pretty well for me to find pipes, but like hj mentioned, if there are more than one line or pipe, you may not have the right one.
    This video will be redone. I had just gone through two major surgerys, and had lost 40 pounds in six weeks. Pretty much just skin and bones that month.

    hj doesn't think this stuff works, but it does. I can personally show him anytime he wants to visit the Seattle area.

    [​IMG]

    Here I am back up to 200 pounds last week.



    A Ridgid Locator video
    Last edited: Aug 23, 2014
  5. WV Bob

    WV Bob New Member

    Messages:
    18
    Location:
    Huntington, WV
    Dang it's nice out there in Seattle isn't it?. I ride mountain bikes so the Northwest has always been somewhere I wanted to go but I think I've waited too long to do much riding out there now. The terrain here just about kills me as it is.

    Anyway, today I tried to figure out if I've got enough drop on the property to come to daylight and have a draining pipe. At the house, it's 7 feet from the top of the clean out to the bottom of the pipe, and it's 130 feet from the house to the furthest lowest point. 130/10*.25 = 3.25 feet for drop. So ideally I need about 10 feet difference between A and B.

    I put one end of some mason's string under the cleanout cap at the high end, stretched it down to the other end and raised it up until the string was level. At that point we were measuring about 9 feet difference between the string and the ground. So if I'm doing it right, there's that about 9' drop from A to B. That's not quite as much drop as I'd like to have but if it gets water down there and out of the basement, it's plenty.

    I could go to a deeper point, but that's right at the mouth of a 24" pipe going under the road, and that gets standing water so I don't want to end the drain there to avoid water covering the drain and preventing the pipe from emptying.

    If anyone sees a problem with the way I measured it, please let me know what I did wrong, or an alternative way to measure it. Of course when I start digging I'll rent a transit along with the excavator and measure it more precisely.
  6. WV Bob

    WV Bob New Member

    Messages:
    18
    Location:
    Huntington, WV
    An update ... I was looking at some photos I took of where the pipe runs and noticed that once I get across the driveway, there's a good 3' drop meaning I only had to dig about 3' down to reach the pipe. So now I've got the pipe exposed downhill from the (first) clog. I plan to cut a length of it out, rent an eel, and clean it out this weekend.

    There are a couple of trees right where the clog is so it's probably roots. Hopefully it will go well with me working it close and not jamming the cable into a clog 50 feet away. It should help to be working at it in an uphill direction too, so I can wash the mess down out of the pipe and not just into the clog again.

    I figure worst case, if there's more clogs downhill from where I dug it up, I'll just get a ditch witch and some rocks to make a "creek" running out of the end of the pipe to the culvert at the road.
  7. WV Bob

    WV Bob New Member

    Messages:
    18
    Location:
    Huntington, WV
    I've got the pipe fully uncovered. The sewer and drain are now side by side where at the house they were not so close. I was hoping they'd get further apart.

    The pipe is gray PVC with slip joints, and it looks like they ran it backward to my way of thinking because the next pipe slips into the prior one instead of over it. A large root has infiltrated the pipe at one of those joints, to the point of causing a leak. I cut that loose but have not yet cut the pipe out so I do not know the extent of the roots in the pipe but I assume it's full of them. The sewer line is broken adjacent to that root, making me think the pressure of the root in one pipe caused a problem in the other, or maybe I broke it digging and it's just a coincidence that it happened right there.

    The attachment shows what it looked like when I first uncovered it. I sure hope I can clear the pipe but won't know until the weekend when I have plenty of time to dedicate to snaking it out. I'm thinking about cutting a slice out of it tonight to see if I can pull enough root out to get it draining in case it rains before doing a proper job of cleaning it out (or digging more of it up to replace). root_in_pipe.jpg

    The flow is from right to left.
  8. WV Bob

    WV Bob New Member

    Messages:
    18
    Location:
    Huntington, WV
    FWIW I I kept digging to make the hole big enough to work in and also so I could see if that root has caused other nearby problems, since it was running into the dirt right beside the pipe. For a while I had a sick feeling it was going to just keep going so I'd have to keep digging but it turned away from the pipe at right about the next joint so I was i luck.
  9. Reach4

    Reach4 Well-Known Member

    Messages:
    2,819
    Location:
    IL
    Did you add any cleanouts?
  10. WV Bob

    WV Bob New Member

    Messages:
    18
    Location:
    Huntington, WV
    Yes I will be adding cleanouts after I cut the pipes open and hog them out. Hopefully clearing this clog will let water flow to where I can find the other end of the pipe and get it fully opened up.
  11. WV Bob

    WV Bob New Member

    Messages:
    18
    Location:
    Huntington, WV
    I cut 'er open, what I thought was a slip joint is actually a pipe broken clean in two. It's solid packed full of roots. So far I've run from the cut up to the house and from the house back to the cut once each way. After eating I've go to turn and work from the cut down to daylight. If that works then I'll Fernco it together so I can flood it to get the mud out. If I have to keep snaking after that, I've got the machine until Tuesday morning. Based on today, a good plumber works his butt off on a job like this. It's not easy work shoving 50 feet of snake cable through a clot and pulling it back

    Attached Files:

  12. Reach4

    Reach4 Well-Known Member

    Messages:
    2,819
    Location:
    IL
    Wow. I see that as a pipe full of dirt rather than a pipe full of roots.

    Suppose you expanded your pit in the picture, and drained with your 5000 GPM pump as needed. Hook that to a hose run to a good place to expel water + mud. Dig out the first foot or so of dirt, and then stick a Clog Hog (or other jetter) into the pipe.

    Just an idea. It looks good on Youtube videos.
    Last edited: Aug 30, 2014
  13. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    27,272
    Location:
    Cave Creek, Arizona
    quote; It's works pretty well for me to find pipes,

    I had a job where they used "dousers" to find the sewer line. By the time they were done digging it looked like a Beirut battle field, and I found the sewer on the other side of the building in about 20 minutes.
  14. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    27,272
    Location:
    Cave Creek, Arizona
    Every time they dug and did not find the pipe, they said, "Well, there was SOMETHING there", even though they could not tell what it was.
  15. Reach4

    Reach4 Well-Known Member

    Messages:
    2,819
    Location:
    IL
    If he does that, he will probably set up a blind test (or double blind test) where the pipe is in a box. You will be asked to detect if the pipe is on the N, S, E, or W edge of the inside of the box. He will wear dark glasses or use a screen to hide his face in case he does not have a poker face.
  16. Terry

    Terry Administrator Staff Member

    Messages:
    15,423
    Location:
    Bothell, Washington
    hj is right in that you don't know "which" pipe you may find.
    But it does find them. :)

    I find it's easier outside where I don't have to worry about overhead conduits. And by the way, I can hand off the wires to anyone else, and they still work. It's not magic. It's just something we were wired with.
    I have found plenty of underground pipes. So sorry hj that you had a bad expience that one time.
  17. WV Bob

    WV Bob New Member

    Messages:
    18
    Location:
    Huntington, WV
    We located and dug up the other end of the pipe. The end was about a foot underground with some bricks, etc, around the end of it, I guess to just keep dirt out of it. We snaked it twice before finding it (wife was mowing grass couldn't hear the snake thumping on first pass). It was full of roots starting where I found the break, bad enough the snake cable got stuck coming back out. We didn't get through the other end until almost dark and it took all we had left in us to just put tools up. More digging, more snaking, more flushing on the agenda for today. I have no confidence that it's going to flow and not stop up again after all this. Also, it rained last night. A great day to be working in a hole.

    Attached Files:

  18. WV Bob

    WV Bob New Member

    Messages:
    18
    Location:
    Huntington, WV
    Actually the eel hogged that out pretty good. It looks like it's mostly just mud in the bottom of the pipe now. The other end actually had root material in it and it didn't come out so easy. At the open end the pipe's got sort of a liner of roots left that the snake didn't touch, so I'm hoping coming at it from the other end will help clear that. Only time and near total exhaustion will tell.

    I still might end up buying a clog hog and pressure washer before this is over anyway. I've got a clogged foundation drain out back, and the exit end of the pipe is always dry. The plumbers got the see snake in about 80 ft before they couldn't push any further, and hadn't found a clog yet. I'm going to have to dig that up too, it was 5 feet deep where the see snake stopped.
  19. WV Bob

    WV Bob New Member

    Messages:
    18
    Location:
    Huntington, WV
    Well the hard part of this project is done. We had a live fire test yesterday when a downpour passed through. The garage trench started backing up, until I realized we had one of those downspout screens stuck in the inlet. When I pulled that out, you could hear the water sucking into the drain.

    What I'm up against now is figuring a way to get the water to run away from the pipe, because it ends below grade. With it dug up like it is the water kept flowing for a long time after the hole filled up, but I need a solution that'll keep the end of the pipe from blocking up. I'm thinking about a catch basin, and a pop-up emitter. Not sure if the catch basin will negate the head pressure that's pushing water out now though.

    Suggestions on how to deal with the below grade pipe, and also industrial strength root killers are greatly appreciated.
  20. WV Bob

    WV Bob New Member

    Messages:
    18
    Location:
    Huntington, WV
    FWIW, we pulled a level string and measured down to the pipe to find grade, and there's about 3 foot of drop over 25 feet. So we're in process of bringing the grade on that section up about 2-1/2 feet, and it'll come to daylight at about 20 feet.
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