Why Does My Sink Gurgle? What Causes and How To Fix a Gurgling Sink

Does your sink make noise when it drains? Strange noises like bubbling, burping, or gurgling in your sink are never a good sign. A gurgling kitchen sink is a sign there is a clog somewhere down the drain. While clogs are most common in the kitchen, even your bathroom sinks can clog and cause gurgling. Here are the basics of a gurgling sink, from the causes to how to fix the issue.

What Is Sink Gurgling?

Sink gurgling is a sound that can occur in a sink drain when there is a blockage or restriction in the pipes that prevents the water from flowing freely. Air bubbles force through the water, causing gurgling, which can indicate a plumbing problem in your home. The blockage of the sewer line or the vent pipe can also produce a gurgling sound. It’s usually a sign that the water and waste can’t flow freely and are backing up, the gurgling sound is the sound of the water and gas trying to escape.

Why Does My Sink Gurgle?

A blockage or air pocket in the drain or vent system typically causes a gurgling sink. Some common causes of gurgling sinks include:

Blockages in the Drain

A blocked or clogged drain pipe will prevent water from flowing smoothly through your pipes and cause your sink to back up. As the water slowly drains, it will create a gurgling sound as the water tries to push through the blockage.

A build-up in pressure causes the gurgling. As the water pushes down on the clog, the air underneath the clog tries to escape. This causes bubbles, burps, and gurgling. The pressure also creates a suction effect, which can pull air down the pipe and cause even more gurgling.

It’s important to note that the gurgling may not happen in the sink. It can also gurgle in a nearby drain, like a bathtub or toilet, if the blockage is severe enough.

Putting food scraps or cooking grease down the drain usually causes clogs in kitchen sinks. Hair and soap scum are usually the cause of clogged bathroom sink drains.

You can clear minor drain clogs with a plunger or drain snake. When using a plunger, use smooth up and down motions to create pressure and flush the clog down the drain. However, you may need to call a plumber for more severe drain blockages.

Clogs in the Sewer Line

The main sewer line is the pipe that carries all the waste and water from the fixtures in your home to the city sewer system or septic tank. When a clog develops in this line, it can block the flow of water and waste, causing it to back up into the pipes leading to the fixtures.

This can create a gurgling as the water and waste try to push through the blockage. Like a blocked drain, pressure builds up behind the blockage and tries to push upward through the pipes.

Also, the vent pipes can release sewer gases if the sewer line is blocked. These gases can create a vacuum effect in the pipes and can cause a gurgling sound.

It’s important to address the clogs in the sewer line as soon as possible to avoid any health hazards or damage to the pipes. A professional plumber should be called to locate and clear the blockage. This may require some specialized equipment, such as a sewer camera or hydro jetting.

Damaged Sewer Pipes

Similar to sewer line clogs, a damaged sewer pipe can cause gurgling in sinks, toilets, and other plumbing fixtures that are connected to the line. A cracked or collapsed sewer pipe can disrupt the flow of water and waste, causing it to back up into the pipes leading to the fixtures. As a result, your sink can gurgle as the water and waste try to push through the restriction caused by the damaged pipe.

Additionally, Cracked or collapsed pipes in the sewer line can cause leaks, which allow air to enter the system and create a vacuum effect in the pipes. This vacuum effect can pull water and waste out of the sinks and toilets, which causes the gurgling sound as the water and waste are sucked back down into the sewer line.

The gurgling can also occur as the sewer gas that is supposed to escape through the vent pipes instead goes back to the house via the leak in the pipe, this can cause gurgling as well.

Cracked or collapsed pipes should be addressed as soon as possible, as they can cause serious problems, such as sewage backups and leaks. Leaking sewer gas can also pose a health hazard. A qualified plumber can locate the damaged pipes, and determine the best course of action, whether it be a repair or a replacement.

Vent Pipe Blockages

Vent pipes are designed to allow air into the drain system to balance the pressure. If the vent is blocked, it creates a suction effect that can cause a gurgling sound.

Blockages in vents are not very common, but they can occur in older homes. The most common causes of these blockages are debris, such as leaves, that have been blown into the pipe. However, animals, like birds or squirrels, may also nest inside the pipe.

A blocked pipe should be cleared as soon as possible to restore proper ventilation and avoid potential sewer gas leaks. It should also fix your gurgling sink. An experienced plumber should be able to clear the blockage and ensure that the drain vent is properly functioning.

Poorly Installed Pipes

Although extremely rare, poorly installed pipes can cause your sink to gurgle. However, this is only a concern if you recently had plumbing repairs or new drains installed. It is also much more common if you installed them yourselves or did not hire a fully licensed plumber.

There are two main types of plumbing installation problems that can cause a gurgling sink. If the pipes are not properly sealed, air will get pulled into the system and create back pressures. Your sink or toilet will gurgle as both the water and air try to escape.

Also, debris can build up in the line and cause a clog if the pipes are not installed at the correct angles. Like any other drain clog, it creates back pressure as the water above tries to flow through.

How Do You Fix a Gurgling Drain?

There are several steps you can take to fix a gurgling drain:

1. Clear any debris from the drain: Use a plunger to remove any hair, food particles, or other debris that may be causing the blockage. You can also loosen clogs with baking soda and vinegar. Pour a cup of each down the drain and wait for the foaming to stop. Then flush the drain with either boiling or hot water.
2. Clean the P-trap: The P-trap is the curved section of pipe located under the sink. It’s designed to trap debris and prevent it from entering the plumbing system. Remove the P-trap and clean it out to remove any debris that may be causing the gurgling.
3. Remove the blockage: If the P-trap is clear and the gurgling persists, there may be a blockage further down the drain. Use a drain auger or a sewer snake to remove the blockage.
4. Check for leaks: Leaks in the plumbing system can also cause gurgling. Check the pipes under the sink for any signs of water damage or leaks.
5. Ventilate: Gurgling can occur if the vent pipes that allow sewer gases to escape the drain system are blocked. You need to clean out the pipe if you find a clog.

If your sink still gurgles after trying these steps, you should call an expert plumber to get the proper diagnosis and fix the issue.

Is your sink gurgling or bubbling? Whether you have already tried clearing the clog or need professional help now, Five Star Rated has local plumbers near you.

Find your local plumber now to have your sink inspected and repaired quickly. Our Five-Star Rated professionals make it easy to get your sink working properly again.

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