Collapsing building © Daniel FriedmanToilet overflow: how to stop

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How to stop a toilet from overflowing: this article describes simple and quick steps you can take to stop an overflowing toilet or a toilet whose bowl is filling and that is about to overflow. Our unpleasant page top photo illustrates the problem with which you may be confronted, often alone, perhaps just after having used the toilet.

Here we explain that quickly lifting the toilet tank lid and taking one or two simple steps can avoid a messy toilet overflow catastrophe.

We also explain how to prevent a septic or sewer system backup during heavy use of a private septic tank and system.

We also provide a MASTER INDEX to this topic, or you can try the page top or bottom SEARCH BOX as a quick way to find information you need.

Emergency Toilet Overflow Rescue Procedure - how to stop a toilet from overflowing

Toilet with tank lid on seatIf the toilet is about to overflow here is what you do to prevent sewage from running over the toilet bowl and onto the floor:

Take off the toilet tank lid - Quickly but carefully
, remove the lid from the toilet tank and set it aside.

You can place the toilet tank lid right across the toilet bowl.

Don't knock the lid on the floor - they break.

Don't waste time moving towels and stuff - we're in a rush to stop the toilet from overflowing.

Toilet flush valve being pushed shutReach inside the toilet and push down the flapper valve that is letting the tank empty water into the toilet bowl - this will stop water from entering the toilet and if you're quick enough, prevent sewage from overflowing onto the floor.

This will be a rubber valve in the center of the bottom of the toilet tank.

This will stop water from flowing from the toilet tank into the toilet bowl.

Don't be afraid to touch the water in the toilet tank - it's sanitary.



Toilet fill valve held shut
Stop the toilet & its tank from further filling by lifting up the float
 that operates the toilet tank fill valve.

This will stop water from entering the toilet tank from the toilet supply line.

The photo shows that water is stopped and the flapper in the toilet tank bottom is shut.


If the water level in the toilet bowl is dropping slowly, keep holding the toilet tank float up in its highest position so that water stops flowing into the tank and into the toilet bowl.

Wait a minute - if in the next minute or two the water level in the toilet bowl slowly drops down to a normal level, you'll be able to release the toilet tank float and let the tank and toilet bowl refill without danger of overflowing onto the floor.

Closing the toilet fill valve
If the water level in the toilet tank is not dropping,
 after a minute or until you can't bear standing there any longer, continue to hold up the toilet tank float while you close the toilet supply valve near the floor or in the wall behind the toilet.

Still holding up the float so that the toilet tank stops filling, reach down and carefully turn off the toilet fill valve. Turn the handle clockwise to close the valve.

If you can't do both, let the float drop and quickly close the valve.

If the toilet supply valve is hard to turn do not force it - it could break and give a terrible supply leak on top of your blocked drain problems.

Toilet bowl fill tube connected normally
If you cannot close the toilet fill valve, or if there isn't one
, remove the little flexible rubber or plastic tube that is sending water into the toilet bowl through the vertical standpipe.

The photo at left shows this tube in its normal position and you can see it shooting water into the toilet bowl refill tube.

The standpipe also supports the flapper valve but the water squirting into the tube is going right into the toilet bowl.

Toilet bowl fill tube disconnected
Aim the flexible little bowl-fill tube into the toilet tank instead.

Now you can let the float drop and let the toilet tank fill.

The reason for this step is that that little tube is sending extra water into the toilet bowl even when the main toilet tank flapper valve has shut.

You're trying to avoid filling and overflowing the toilet tank.

The photo shows us directing the bowl-fill tube water into the toile tank instead.

Once the toilet tank has filled you can clip this tube back in place where as shown in the photo before this one.

OK so You Prevented the Toilet From Overflowing onto the Floor, What Next:

Photo of septic tank being pumped

If you have had sewage back up and spill out of toilets into the building, cleanup is needed and you may face bacterial hazards. See SEWAGE CONTAMINATION in BUILDINGS for advice.

Why Does the Septic or Sewer System Back Up During a Party?

Sewage backup into bathtub
Indeed it seems to be just the luck that we are living happily along not giving the septic tank a thought until we have a bunch of guests over for Thanksgiving, Chanukah, Christmas, or a graduation party. Why is it that at events we often see the septic system backing up?

The photo shows sewage water backing up into a bath tub. This is what can happen at bottom floor fixtures in a home when the main drain is blocked or the septic system is blocked and you keep flushing toilets or running fixtures at upper floors. Don't do this.

Septic systems seem to fail during a party because the septic system was already in trouble, but our usage was modest enough that we just weren't noticing it.

The surge of waste water entering the septic tank cannot flow into a flooded drainfield so sewage may back up into the home, usually at the lowest plumbing fixture. Sometimes it's not the wastewater surge but someone flushing something down a toilet that blocks a drain - that's a problem that can be cleared by a plumber using a plumbing snake or drain router. But often the problem is in the septic field itself.

Readers should see CAMPING & EMERGENCY TOILETS and also see ALTERNATIVE & WATERLESS TOILETS for a discussion of camping toilets, chemical toilets, emergency-use toilets, waterless toilets, graywater systems, composting toilets, home health care toilets, incinerating toilets, outhouses, and latrines.


Continue reading at TOILET REPAIR GUIDE or select a topic from closely-related articles below, or see our complete INDEX to RELATED ARTICLES below.

Or see BLOCKED DRAIN REPAIR METHODS to try clearing your blocked drain before going to more drastic measures.

Suggested citation for this web page

TOILET OVERFLOW EMERGENCY at - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.


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