For a while now my hall restroom toilet when flushing will either go down slowly, water will drain but nothing else, or just all together get clogged. I plunge over and over until it finally flushes and again within days same problem persists. Finally it clogged again so I thought. I plunged and water slowly went down. Meanwhile until maintenance comes to check out problem toilet IS NOT in use.

Last night & today I’ve woken up to a restroom completely flooded. With the toilet bowl overflowing with water. 1st thought shut the valve off - done. I cleaned up the mess, emptied the bowl completely and left it alone. Again woke up to a restroom completely flooded and bowl overflowing.

  • Why is water steadily rising up into my toilet bowl?
  • Where could this all be coming from?
  • what other toilets do you have, are those working
    – Traveler
    Oct 20, 2022 at 7:28
  • My master bathroom and yes that toilet is working fine. (thank goodness) Oct 20, 2022 at 13:10
  • The shut off valve should have stopped water filling the tank, which with not using the toilet should have stopped the flooding. Is it cleaner water or the nasty that is flooding?
    – crip659
    Oct 20, 2022 at 13:15
  • when it (still) overflows, is there water in the tank or just the bowl? if there's any in the tank, the supply valve is not fully closed; they can be quite stubborn.
    – dandavis
    Oct 20, 2022 at 22:04
  • Clear water fills the toilet bowl no water in the tank & valve is securely tightened/ off Oct 22, 2022 at 7:33

2 Answers 2


There's a blockage in your sewer pipes. You mentioned waiting "until maintenance comes to check ..." which suggests you may not own the building. That's good news for you -- call again and tell them there seems to be sewage backing up into your room and that they'd better get a plumber immediately.

A plugged sewer vent pipe can also cause weird problems with toilets, but that more often manifests as a toilet that "burps" air bubbles and causes lots of splashing, or causes the water to be vacuumed out of the bowl. Since you have water that rises and stays high it sounds more like a blockage in the drain line downstream from your toilet. The rising water is the waste water sent down a drain or toilet elsewhere in the building.

There are a number of tools a person could use to clear such a blockage. A drain snake or auger is a simple but effective option. It's just a a wire coil -- a long spring -- which one feeds into the drain with hopes that it'll either dislodge the blockage and send it floating away, or else grab the blockage and allow it to be pulled out.

small drain snake (photo: thespruce.com)

Snakes are offered in multiple diameters and lengths. A larger diameter snake is used when the pipe is larger - if the snake diameter is too small, it'll be prone to tangling itself in the pipe rather than feeding through. A toilet-sized pipe will need a snake that's perhaps 5/8" or larger diameter. If the blockage were in the toilet itself then a short snake would do, and that's a tool that's reasonable to own.

toilet snake (photo: amazon.com)

In your case though, where the blockage is somewhere further down the pipe, a longer snake will likely be needed. These are often packaged on a cart. This is the sort of tool a homeowner would usually rent rather than buy -- or, probably even more often, hire a plumber to do the job.

large drain snake (photo: vevor.com)


Greg Hill has an excellent answer for the blockage issue, but that won't cause the bowl to overflow over night and fill the bathroom floor.

That is, most likely, caused by a fault with the fill valve within the toilet tank itself. It could be that the float that is designed to rise with the water and shut off the water flow when it's the right level has gotten jammed so it's not rising (high enough). It could also be an issue with the valve itself not shutting when the float rises. Another possibility is that the flapper valve that seals between the tank and the bowl isn't sealing properly, allowing water to constantly leak into the bowl.

If it weren't for the blockage, you might never notice this leaking issue, because the toilet will flush itself when the water in the bowl rises high enough. Someone would have to be in the bathroom or close enough to it when it flushed itself to notice the "phantom flusher".

Make sure you tell maintenance about both issues, and they should have you taken care of in no time.

  • 1
    The blockage is likely in the sewer pipe that is shared among apartments. When someone upstairs flushes the water comes down the pipe and, lacking another means of exit, flows into and out of your toilet. I remember this happening in college in an apartment I shared with a couple of other guys.
    – Hot Licks
    Oct 20, 2022 at 12:56
  • That is a possibility, too, @HotLicks. One that I obviously hadn't thought of. However, there would likely be several people having issues, and it would, likely effect more than just this one toilet from the OP's apartment. A blockage in a shared main drain line would probably effect the kitchen sink, other toilets, dish/clothes washer, etc. Additionally, it would likely happen at all times of the day/night as others use water, not just overnight.
    – FreeMan
    Oct 20, 2022 at 13:00
  • Thank you all for this. I will let my landlord know. And mention all of this. Just so it’s clear though I live in a house not an apartment which is why I’m more thrown off on what is going on and how is this even happening. I work so by time I get home there is water everywhere with how much water is being brought in through this toilet bowl. Oct 20, 2022 at 13:06
  • Even with a leaking flapper valve or float, the OP would notice water constantly running in the toilet, but it shouldn't overflow. This is obviously a blockage some where in the drain pipes or, and here is the big OR!.... if the house is on septic rather than sewer, the septic system may be failing. So very coincidentally I just had to deal with a similar situation at my house: There was a plumbing failure in the pump chamber which filled both the pump chamber and the other chambers, once the plumbing was fixed, still had issues, turned out to be a plugged baffle on the inlet. Oct 20, 2022 at 15:09
  • Thank you all for your answers. Finally had someone come look at the issue. Removed toilet and welp apparently roots are growing in the pipes. Literally the whole pipe looking down into it is consumed w/ roots!!! So now it’s a waiting game on having the owner pay to have someone come out & fix this huge issue Nov 2, 2022 at 2:55

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