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Strange plumbing problem

  1. Dec 4, 2012 #1
    I dumped a bucket of water into my bathroom sink (nevermind why, that's a whole other can of worms), and afterwards my sink has started having problems. It hasn't been draining properly. I'll wash my hands and the water will stay in the sink not draining at all. Then I'll come back later and the water will be gone. Then I'll come back later and the water is back again. This must be a result from me dumping the water into the sink, because that's when all this started. Maybe the pressure of all that water did something?

    I'm going to give an illustration of what I think is wrong, and maybe someone who knows about plumbing can tell me if this makes sense.
    Ok, let's say you have a pipe that's curved like the letter J. You pour water into the bottom part, but the water will stop going in at a certain point, because it's not going to climb up the pipe, so it will appear like it's clogged, but it's not. Is that what could be happening in the piping of my sink? For some reason the pressure of the water caused something to change so that it just won't flow?

  2. jcsd
  3. Dec 4, 2012 #2


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    The curve in a kitchen/bathroom sink pipe is such that it would never normally allow water to back up into the sink by itself. There has to be a blockage.

    Most likely dumping a large flow of water in all at once dislodged a partial blockage that was not causing problems for normal flow but now that blockage has moved out more into the center of the pipe and thus IS blocking normal flow, but lets it through slowly.
  4. Dec 4, 2012 #3


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    The blockage is probably down stream of other drain pipes (from a higher location) that may be supplying the other backup water.
  5. Dec 4, 2012 #4
    I had a similar problem in my kitchen sink. I fixed that by filling the sink with water and I guess the pressure of all that water dislodged the blockage.

    I can't do that with the bathroom sink because the pipe is leaking. I've tried pouring drain cleaner down the drain, but I don't think it's even reaching to where the blockage is.

    The reason I was pouring water down the drain was because my bathtub drain had a clog, and so I poured some drain cleaner down the drain, and since there's also a leak from the faucet, I put a bucket under the leak so it wouldn't wash away the drain cleaner.

    Yeah, these apartments suck. I'm just gonna go talk to management.
  6. Dec 4, 2012 #5


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  7. Dec 4, 2012 #6
    That's a good idea. I forgot about those. Thanks.
  8. Dec 4, 2012 #7


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    This is the problem with drain cleaners. If they don't work, then you've got a sink full of hazardous chemicals that makes it hard for you to fix things properly.

    Try a plunger, but be careful you don't splash the drain cleaner all over you and all over everything else in the bathroom. It might be prudent to wear some goggles.

    Once you manage to get the drain cleaner out, just disassemble the pipe and clean out the curved pipe. That's where are the junk tends to accumulate. Since it's leaking, it needed to be reassembled with new gaskets anyway.
  9. Dec 4, 2012 #8


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    But don't make the classic mistake, which is:

    After clearing out all the gunk, flush it away down the sink .... BEFORE you re-assemble the U bend.

    Actually, I don't think there's any point posting that warning. There are some things in life you can only learn by practical experience :cry::cry::cry::cry:
  10. Dec 4, 2012 #9
    I tried taking the pipe off. I put a bucket under it, unscrewed it, and looked inside and there was a chunk of calcium or whatever in there that crumbled when I touched it. I thought maybe that was acting as a valve or something inside the pipe. So that fell out and the pipe was pretty clean otherwise. I reassembled the pipes and I'm still having the exact same problem.

    Anyone have an idea why the sink would drain all of a sudden, then refill itself with water from the drain and stay there for a while, then drain again, etc?
  11. Dec 4, 2012 #10
    I think someone mention a plugged pipe that is beyond the point where other sinks drain. When they run the water comes up in the sink. It is possible that the pipe isn't completely plugged, so the water gradually goes down.

    The fact that you mentioned that there was no water in the pipe under the sink surpized me. There should be a P trap or some other trap under the sink with water in it. Did any water drain into the bucket when you opened the line? If so it is OK and a trap is there.

    http://en.wikipedia.org/wiki/Trap_(plumbing [Broken])

    From a bathroom sink hair is the usual culprit.

    The plug may be a few feet down the line. If you have the trap (u shaped thing) disconected under the sink there are a number of products available at home improvement centers or an Ace Hardware store.

    The one below is fairly short, but it works great on hair.


    Once the sink is draining run a lot of water through it or the plug may end up further down the line.
    Last edited by a moderator: May 6, 2017
  12. Dec 4, 2012 #11


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    If you are in an apartment block, most likely there is one drain pipe going vertically past all the floors, and your sink and bath pipes empty into it.

    When somebody on the top floor empties their bath, they are probably filling up pipe the above the blockage, and when the water gets up to your level, it is backing up from the drain into your sink.

    This sounds like a job for a professional with a high pressure water pump and some flexible drain-rods to me. Best move anything important out of your bathroom, in case the next "high tide" overflows the sink onto the floor.
  13. Dec 5, 2012 #12
    I took the u shaped pipe out and put a bucket under it and left it there the rest of the day. Nothing came out. Then this morning I noticed some water on the floor, and I looked and the bucket was full of water. I poured it into my bathtub and there was dirt and other debris in it. I put the pipe back on and I guess I'm going to get the maintenance to fix it. It's only two story apartments and I'm the top floor.

    It's strange because if I fill the sink with water, some of it will drain, and then completely stop draining for a while. No water will go down. Then I'll come back later and all the water is gone. Then I'll come back later and the water has returned.
  14. Dec 5, 2012 #13
    Yea, I'd say they need to snake the plumbing for the building.
  15. Dec 5, 2012 #14
    I am still thinking that the main sewer line is not plugged. When that happens water comes up in the bathtub or shower first.

    More than likely there is an partial obstruction in the line just past the point where your sink ties in to a branch line. The water that comes out has to be coming from a sink higher than the bathroom sink and that would usually be the kitchen sink.

    On a second story job (pun) a plug could be beneath your floor level, but inside of a wall.

    You will have to run a plumbers snake or have management do it. The best place to start is inside the pipe behind the sink where it goes in to the wall.

    Along with the plug there will be a lot of smelly stuff in there. There is decaying soap and hair in a bathroom sink drain pipe and black decaying garbage in a kitchen sink drain pipe. It can be really messy and the smell takes forever to get off of your hands.

    So have some rubber gloves, a small plumbers snake, and new gaskets on hand, or call the management to get someone to come and do it.:wink:
  16. Dec 5, 2012 #15


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    Quick hijack. My bathtub drain has been super slow, but the bathroom sink got clogged to the point of standing water that would take overnight to drain.

    So I poured draino down the sink and cleared that clog. Next, I went to the shower and ran the water, knowing it would back up, and the drain ran fine. Clearing the sink clog fixed the bathtub drain. Anyone know why?
  17. Dec 5, 2012 #16


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    Attached Files:

    • clog.jpg
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  18. Dec 6, 2012 #17


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    GASP!! That's not my hair BTW!! That's Evo Child's hair!! The hair dressers would charge me double to cut her hair when she was little, they all said she had the hair of three people. No one wanted to do her hair, it took forever.

    Thank you dl!!

    End hijack.
  19. Dec 6, 2012 #18
    I noticed there's like little hairs inside my sink every once in a while when the water comes up into the sink. The hairs aren't the color of my hair. I live alone. Oh god.

    I told management. Hopefully they come soon to fix this.
  20. Dec 7, 2012 #19
    Well I just came home from work and the entire apartment stinks. While I was gone, the sink filled itself with nasty water for no reason at all, and then drained for no reason at all after leaving its stink behind.
  21. Dec 7, 2012 #20
    Guess you've got to wait for you're landlord. I'd call and remind him that at any time he runs the risk of the apartment floors becoming inundated with smelly refuse water.
  22. Dec 7, 2012 #21


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    What a pain. Does the sink have a pull stop? Maybe you should keep it plugged.
  23. Dec 7, 2012 #22


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    I would move to a top floor apartment and let someone else deal with your ****.
  24. Dec 7, 2012 #23


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    I'm wondering if you have a clog in the vent stack (which would be outside your apartment and beyond your capability to deal with, anyway).

    With no vent stack, adding new wastewater to the drainage system would be like holding water in a straw by putting your finger over the top. Of course, in this case, a new vent source can be opened by simply pushing the water from the trap (the curved part of your drain) back up into your sink.

    Usually, the water in your trap forms the seal that prevents gases from the drainage system/sewer/etc from coming back up into your home. They escape out the vent stack, instead.
  25. Dec 7, 2012 #24
    It doesn't close all the way. Behind the faucet is a thing I can pull up and down. If I pull it up, the drain "closes". I looked under the sink and this closing mechanism goes into the bottom of the sink and pulls down or pushes up on the valve thing to close or open it. Well water is leaking from where it goes into the sink. (It's hard to explain) So even if I close it, the water will still leak into the bucket under the sink (it stinks horribly under that sink). I closed it just to see if that helps at all.
    I am the top floor. Do you think I could be getting water from the neighbor?
    And if so, they have to be having the same problem as me, right?
    I'm about to take the pipe off from the bottom and stick something in the pipe going into the wall so I don't get anymore of that damn disgusting water coming into my sink. Do you think I should? It won't mess anything up, will it?
    If not, do you have any idea on what I could stick in there? Will a washcloth stuffed in there work?
  26. Dec 7, 2012 #25


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    This is only indirectly related to your problem. The stopper mechanism needs a new gasket/seal down by the pivot ball.

    I say it's indirectly related because it sounds like this is a low rent apartment where the owner/manager does all of the repairs himself, even though he's not really a plumber. The building's plumbing system has more problems than you count.
    Last edited: Dec 7, 2012
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