Toilet Water Rises Too High When Flushed

Surprises don’t come all that often from the toilet, but when they do, they are usually unpleasant.

Seeing your toilet water rise too high when flushed may cause you to panic. What if it clogs? What if it overflows?

While a high level of water in the toilet is definitely not a good sign, there’s no need to panic. It can be due to a broken piece, blocked vent, or clogged drain.

The normal toilet water level is around one or two inches below the overflow tube opening. If it is consistently rising above that level, you can try to use a plunger and check whether there is any dust or debris inside. Finally, if that’s all clear, and the water is still filling up, you’ll need to check whether all of the parts are working properly.

In this article, we’ll go through some of the most common causes of high water in toilet after flushing and offer solutions to the problem.

Why Does My Toilet Water Rise When I Flush?

There are three main reasons why toilet water keeps rising when flushed. There might be a blockage in the drain, or a blockage in the vents, or some of the components may not be working properly.

Let’s briefly go over each possible cause.

Drain Blockage

If the water in your toilet is rising too high, you may have drain blockage. Usually, when you flush, the atmospheric pressure pushes the water up before draining it.

If there is a blockage in the outgoing drain, the water from the cistern accumulates in the toilet bowl. Drain blockage prevents water from flowing away.

Vent Blockage

As mentioned above, the main operating mechanism of the toilet is pressure. Vents allow the air to pass through and create atmospheric pressure. Air flows in from a pipe above the toilet that is sticking through the roof. If a vent is clogged, the air can’t flow into the pipes, leaving the water stagnant in the system. As a result, water might keep accumulating, rising higher and higher in the toilet bowl every time you flush.

Faulty/Broken Components

Finally, toilet water rises to an unusual level when the components of the system are faulty or broken.

The cistern has a mechanism that lets the water pass into the toilet once you press the flushing button. The first component to check is the flush valve seal. It’s the most common cause of flushing problems.

If the valve seal is intact, the next suspect is the ‘flapper’. The flapper is a small plug that is sealing the drain hole on the bottom side of the tank.

Whenever you press the flush button, the flapper helps the tank drain, and then it lets water back into the cistern so it’s ready for the next round. If something’s wrong with the flapper, the water might be passing the valve flapper or passing through into the overflow tube, causing the water levels in the toilet bowl may be rising.

What to Do When My Toilet Water Rises?

Now that you’re familiar with the secrets behind rising water levels in the toilet after flushing, let’s see what you can do immediately to address the problem. In the following paragraphs, we’ll discuss how to stop toilet water from rising.

Clear the Drain

The most common cause of high water levels in the toilet is drain blockage so the first step is to clear the drain.

Homemade Solution

There are many ways to do this, and we recommend starting with light homemade solutions. Mix hot water with dishwashing soap and pour it into the bowl. It should help dislodge the drain.

Store-Bought Solution

If homemade products fail, you can try store-bought chemical cleaners such as the eco-friendly Green Gobbler, or Drain OUT. These are sometimes labeled as ‘drain openers’ or ‘drain cleaners’, and they are usually strong enough to dissolve any type of scum blocking your drain, however, they do require some time or even repeated application.

Put on Long Sleeve Rubber Gloves

…You can guess what for. A pair of arms-long rubber gloves will let you reach deep into the plumbing and pull out anything that may be clogging the drain.

The golden rule is that nothing but organic waste and toilet paper should be flushed down the toilet, but many of us still use some kind of rule of thumb to estimate whether or not a certain product is okay to flush (e.g. hygienic pads no, but paper towels yes, sometimes).

Keep proper care of your toilet system by disposing and flushing only human waste and toilet paper. Every other type of trash should be thrown separately.

Use a Plunger

A plunger is a second-best option for removing anything that may be stuck further back in the drain. If you don’t have a toilet plunger, make sure to get one, because it’s the ABC of proper toilet care.

A toilet plunger is usually bell-shaped and it’s meant to be positioned and centered with its tip over the hole. Make sure that the angle is well-adjusted so that the vacuum is optimal.

You can easily find a good toilet plunger online. For example, Mr. Siga comes in a combo with a toilet brush and holder, so you can naturally fit it into your restroom. There is also this Clorox model with an opening base.

Use an Auger or Snake

This tool is used to extend a tube into the plumbing of the toilet and dislodge anything that may be stuck in there. The snake is j-shaped and has a long cable you can push along the piping to remove anything that may be stuck in there.

The best ones are those with rotating handles that extend up to three feet in length. All you need to do is insert the cable into the bowl and rotate the handle. You can try hooking the blockage or nudging it until it flows down the pipe.

If you don’t feel like going to a local vendor (or there isn’t one nearby) to buy a toilet auger, don’t worry. There are many good models you can purchase online. The one we strongly recommend is the Rigid K-3 model with a bulb head and a 3-foot snake.

Clear the Blocked Vents

If there is a clog in the air vent, you need to climb up on the roof and see what’s going on at the source. Be careful as this is quite dangerous, and you may want to secure yourself with ropes and have a partner. You’ll be pushing a garden hose through the opening of the vent. The water will then clean the pipes, but it may backflow due to debris. In that case, you can use the auger to break hard pieces of waste and then clean again with the hose.

Fix Your Flapper

To fix the flapper, you need to switch off the water supply first. Then, check whether the seal of the flapper is broken or not. You can either purchase a new flapper or its composing pieces at the local plumbing shop or online. Just check whether you need a 2-inch or a 3-inch model before buying.

Also, it’s possible that the issue lies with the flapper’s chain. You can try resetting or cleaning it, or adding links to it.

Adjust Level of Fill

Inside the cistern, you can see a float attached to an arm with an adjustable screw. The longer the arm, the more water the cistern will hold. Perhaps all you need to do is lower the amount of water in the tank, especially if the valve is not in the best condition.

Call an Expert

Finally, if none of the steps we have suggested so far are working, and you still think that something may be blocking the drain or the vent, consider giving a call to the plumber.

Sometimes, the blockage is so far back in the pipes that special tools and manual expertise are needed to release it.

If there is a huge blockage, the pressure could cause the pipes to burst and damage your home.


If you are trying to understand why toilet water rises when flushed, check potential blockages in the system or malfunctioning pieces in your toilet.

While a few rounds with a toilet plunger is usually a good enough solution, sometimes it may be necessary to take things further and put your hands inside the toilet or even climb to the roof to see what’s up at the source.

Here is a helpful video that shows how to adjust water levels in a toilet.

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