Why Does Your Sink Drain Water Slowly?

The Short Answer Is: A slow-draining sink is often caused by a buildup of debris, such as hair, soap scum, or food particles, in the drainpipe or trap. To fix it, start by removing the sink stopper and using a tool like a drain snake or a bent wire hanger to pull out or break up the clog. If the problem persists, you may need to remove and clean the P-trap or seek professional plumbing assistance for more complex issues.

Every once in a while, a sink sink draining slowly causes homeowners grief. When the sink drains slowly, tasks take twice the time they usually do, or longer, because you have to wait for the water to leave your sink! This makes doing dishes and other kitchen tasks particularly frustrating as well as bathing. Beyond this inconvenience, there are more serious repercussions to a slow-draining sink.

Indianapolis, Indiana homeowners look to Mr. Plumber’s licensed plumbers to help with their slow sinks. We cover some of the problems homeowners experience when this issue occurs and how they happen. These issues are all easy for a plumber to handle, so we also cover the steps professionals take to fix the problem. 

Sink Draining Slowly: The Problems

The severity of problems from a slow-draining sink ranges, but most are minor. Of course, this doesn’t make them any less annoying. Oftentimes, a sink draining slowly consumes a large amount of your time because of the all the extra cleaning you have to perform. Most of these inconveniences require your time and energy to fix, and they don’t even resolve the issue at hand: a clog. Here are all the problems homeowners experience with slow-draining sinks.

Mold and Mildew

Slow-draining sinks obviously collect pools of water in the basin. If the water stays there long enough, tiny mold and mildew spores are able to grow in the drain. Mold and mildew enjoy warm, damp, and dark spaces, which makes a drain the perfect host site. A sink draining slowly allows the water to stagnate in the drain, which makes it easier for these substances to grow.  


Though a small problem, it’s worth noting the amount of frustration homeowners experience with a sink draining slowly. If you brush your teeth only to look down and see a pool of water with toothpaste in it every single day, it becomes a nuisance. Or when you do the dishes and try to drain the dirty water, but it sticks around and smells up the whole kitchen. In these instances, you spend time waiting for the sink to drain, which results in frustration.


In bathroom and kitchen sinks, soap scum builds up in the drain. This happens normally, but when the sinks drain slowly this problem grows larger. Soap scum builds up in the actual basin, on the drain stopper, and in the drain itself. Not only does this create more cleaning for you, excess soap scum in the drains contributes to clogs.


Like with build-up, smells accumulate when a sink draining slowly occurs in your home. If the slow drain occurs because of some kind of clog, the smell likely comes from the blockage. However, the drain itself also smells when the water moves slowly because mold and mildew growth are more likely. Plus, the water in your sink carries a smell if your activity involved food, dirt, or another substance. If it drains slowly, you’re stuck with the smell until it drains.


Depending on the water in the sink, stains are possible with a sink draining slowly. Soap scum, food, drinks, and more form rings in the sink if left there for too long. This means if the water drains slowly, the substances in the water are more able to form stains. These stains are often hard to remove and frustrate homeowners.

Sewer Line Issues

Finally, sewer line issues are possible when a sink draining slowly happens in the home. Slow drains usually point to a larger problem in the system, so if the drains in your home have a hard time draining, it’s important to contact a plumber. Single-fixture problems are often minor, but if all of your drains are slow, a bigger problem is likely the cause. 

Sink Draining Slowly: Causes and Corrections

While the problems from a sink draining slowly are frustrating, there are ways to solve the problem. In order to remedy these issues, homeowners must know the cause. The only way to accurately diagnose the problem is through a professional plumber. Here are some the most common causes—and the best solutions—to slow-draining sinks. 

  • Minor clogs. Most of the time, a sink draining slowly stems from a clog in the pipe. This problem has many at-home solutions, but there is no way to tell if it’s the real cause without the help of a plumber. A plumber uses a camera to view inside the pipe and locate the clog. From there, they remove the blockage with a snake or auger, then clean the pipe with a forceful blast of water. Most clogs consist of hair, food, dirt, and soap scum.

  • Tree roots. If tree roots grow into the sewer line, problems occur all throughout the system. This includes slow-draining sinks. Only a plumber has the ability to solve this problem. They need to remove the tree root and replace the section of pipe with damage. This often costs more than other repairs and takes up a lot of time. Unfortunately, there’s little to do in terms of prevention for this issue.  

  • P-trap problems. The P-trap refers to the section of pipe directly under your sink. Clogs often lodge in the bend of the P-trap, which makes the blockage more difficult to remove and harder to see from the drain. If you pour grease down your kitchen drain, you likely experience clogs in the P-trap because the grease settles in the bend and allows other materials to stick to the pipe. In most cases, a plumber needs to clean the P-trap.

  • Septic tank sludge. Problems with the septic tank also contribute to how fast your sinks drain water. If sludge collects in the tank, it blocks up the main line. This causes the drains to slow throughout the home. Again, a plumber is necessary for this problem because they are able to properly diagnose the issue with the septic tank. In the best case, the tank just needs a quick bath with a bleach and water solution. 

  • Drainpipes. Did you know you have pipes specifically for draining? These pipes go beyond the ones that supply water to your sinks. Every drainpipe connects to the main sewer line, which means problems are able to form anywhere along way. If you have leaks, clogs, sediment buildup, or any other problem along this line, you experience slow drainage. The only way to diagnose and fix any main line issue is with the help of a plumber. 

  • Vent pipes. Vent pipes allow fresh air to travel through the drainpipes because creates a vacuum necessary for the pressure to equalize and remove gases that cause odors. Unbalanced air pressure causes a sink draining slowly. A key component of this stems from the location of the vent pipes, which come from outside. In the winter, these pipes become covered in snow and any leaves left from autumn. In most cases, removal of the blockage fixes the issue. 

  • Deterioration. Either through age or chemicals, pipes, and other plumbing elements experience corrosion and deterioration. If you use chemical cleaners to clear the drains, this corrosion occurs more quickly and more often. Rust build-up also contributes to this problem. Plumbers usually need to replace the damaged pipes with new ones, which is expensive.

  • Stuck objects. Sometimes, small objects like jewelry or toys lodge in the openings of pipes on accident. This causes the water to drain slowly. When this happens, simply use a straightened hanger to loop onto the object and pull it out. Alternatively, call a plumber and have them remove a section of the pipe to remove the object that way if you are unable to reach it. 

  • Old plumbing. Lastly, old plumbing generally has a harder time with all functions, which makes problems more frequent. In particular, a sink draining slowly is a large side effect of age. The fixture, pipe, or drain are all able to slow the flow of water, so make sure to keep everything up to date. Regular maintenance also prolongs the life of the system, so schedule a yearly appointment to keep this problem at bay.

Benefits of Correcting Slow-Draining Sinks

The most obvious benefit of correcting a slow-draining sink is that the sink drains faster! Any solution to slow drainage improves the speed, but what are the other benefits. Do fixes for a sink draining slowly have other benefits to the plumbing system? 

In fact, they do! Here are the other benefits you receive when you have a professional correct your slow-draining sink.

  • No mold or mildew. Not only does a fast drain keep mold and mildew growth to a minimum, but plumbers also help with removal of these substances with cleaning. If you do experience growth after a sink draining slowly plagues your home, you have several solutions to choose from. For example, use a bleach and water solution to clean your bathroom sink drains.

  • Clean pipes. Because most slow drains are due to sediment collection in the pipes, a plumber often needs to remove the sediment. When they do this, they remove months—maybe even years—worth of sediment from the pipes. When the pipes are cleaner, clogs have a harder time forming. 

  • System improves. Lastly, when a sink draining slowly receives treatment from a plumber, your system improves overall. A plumber knows exactly how to diagnose and solve problems with drainage, which means they don’t add on to the issue with incorrect repairs or replacements. While homeowners like to know they are able to perform at-home fixes for problems like this, it’s always better to contact a professional to avoid additional problems. 

Sink Draining Slowly? Call Mr. Plumber!

If you have a sink draining slowly in Indianapolis, Indiana, schedule repair work from Mr. Plumber today! Our plumbers know exactly how to handle this issue. For any of your plumbing problems, we have your back!

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