do cockroaches climb through drains?

Do Cockroaches Come Up Drains?

Cockroaches are invasive pests that seem to come from everywhere. They’re nimble enough to manipulate any crack or gap, so your drains may be the perfect target. After all, they connect to the sewers, they’re moist and dark, and they offer access to food sources. This can leave you wondering if your shower drains, kitchen sink, or even the toilet are at risk.

Cockroaches do come up drains as they have access via the sewer and from cracks in your pipes. However, modern toilets in functioning condition are all but impossible to invade. However, your shower drain, kitchen drain, or floor drain are options. Modern plumbing is designed to keep most sewer roaches out, but there are exceptions.

Roaches that invaded your home through other means could decide to live in your drains. To stop the roaches, you can use coverings or water traps. You can also keep the walls of the pipes moist, so it’s harder for roaches to climb. In the worse cases, you’ll need more advanced roach traps or an exterminator to keep the pests at bay.

Do Cockroaches Come Up Through Bathroom Drains?

Cockroaches will come through your bathroom drains. Whether the drains are used infrequently or every day, they are still portals to the outside world. Cockroaches are able to come through the smallest holes. They will look for access in the pipes, via a crack, leak, or other means. If found, you can be sure cockroaches will exploit it.

With that said, most homes don’t have cracked pipes that are left unattended. Of all the disrepair that an apartment building or house can have, water leaks are handled most quickly.

Can Roaches Come Up the Toilet?

Cockroaches can, technically, come up your toilet. However, it’s very difficult for them to do this successfully.

  • With a water trap, most toilets are designed to prevent waste or bugs from breaching into the bowl.
  • Toilets are constantly full of water, so the roaches would have to swim.
  • Toilets are used frequently, so it’d be difficult for a roach to make progress up the pipe.
  • Unlike sinks or floor drains, toilets create a suction that increases water pressure when flushed. This is far more difficult to swim through.  

As long as your toilet is working and filled with water, don’t worry. No roach will climb up while you’re sitting there. The only toilets in danger of a roach invasion are:

  • Dry toilets, allowing roaches to climb up the pipes, not swim.
  • Toilets in disrepair, with a broken water trap.
  • Old toilets that lack a water trap, as some outdated designs do.
how to stop cockroaches coming up drains

Can Cockroaches Swim?

Drains, according to their main purpose, see a lot of water. The drain of your kitchen sink will have regular use, and a toilet will have even more. This can leave you concerned. If roaches can swim, won’t they circumvent the water and come right up? Even worse, will they use the water to paddle up through your drains?

The good news is that cockroaches are terrible swimmers. Their legs can’t propel them with any kind of efficiency. Whether in water or underwater, they will instead uselessly tread water. You may find them lightly spinning in circles, but that’s the most traction they can get.

On the rare occasions they’re forced into swim, they survive with two physical advantages:

  • They can hold their breath for up to 40 minutes.
  • They can float with great efficiency.

As such, they can withstand being submerged in a sewage tank or blasted with the water pressure of a flushing toilet. However, while they won’t drown, they won’t overcome it either. If you run water down your shower drain, kitchen sink, or toilet, don’t worry. You’re not providing a swimmable entryway to your home. In fact, you’re washing out cockroaches.   

Can Roaches Float Up Your Drains?

With that said, there is an exception. Because roaches are great floaters, you may find one bubbling up through a clogged drain. If the pipe is full of water and a cockroach is inside, it can use its floating abilities to “crawl” up a drain or pipe.

This will be by accident, though. It’s completely by chance, so the cockroach will be as surprised as you. More-so, a functional water trap will prevent it from happening in your toilet.

Can Roaches Come Up the Shower Drain?

Of all the drains in your home, it may be the most appealing to roaches. Showers have ample food sources washed down them, including:

  • Soap
  • Hair
  • Build-up of grime

Likewise, you won’t clean a shower drain as often as your kitchen sink. This can result in a build-up of all kinds of material. The good news is, most shower drains have a protective covering over them. Depending on the thickness of the holes, cockroaches may be unable to pass through.

However, your drain may be open or have a covering with larger gaps. Cockroaches may use this as a highway into your home.

Do Cockroaches Come Up All Floor Drains?

Cockroaches don’t play favorites when it comes to drains. However, you may notice drains that receive less use being invaded by roaches. For example, if you have a floor drain in your garage or outdoor shop.

The roaches won’t be tantalized by food sources, like in kitchens and bathrooms. However, these drains may have access to the sewer and see less activity. Without the barrier of water constantly washing them down, roaches can find easy access.

Why Do Roaches Come Up Drains?

Cockroaches are opportunistic. They will take any chance to access food, shelter, and comfortable temperatures. With that said, outside forces could be motivating your roaches to come up drains.

Following Other Cockroaches

Roaches have a keen sense of smell and will follow scent trails. As such, if roaches smell the presence of other roaches in your drains, they’ll go in that direction. This may include:

  • Roaches that are infesting your home in general
  • Roaches living in your drains, but who accessed the home in other ways
  • Roach droppings down or around your drains
  • One roach that climbed through your drain by chance, but that can now attract others.

Once a scent trail is established, you’ll need to take action to remove it. This can be through rigorous cleaning.

Attracted By Odor

Like the smell of kitchen food or a scent trail of other roaches, you may find organic waste luring in roaches. This can include uncleaned drains. For example, shower drains with a build-up of hair or soap can be tempting to pests.


Cockroaches are natural explorers. In their constant search for food and amicable temperatures, they’ll go anywhere. By chance alone, this can include your pipes. If there’s very consistent water flow as a barrier, that may deter them. In any other case, your drain will serve as a perfectly natural route in their journey.

Sewage Back-Up

A backed-up sewer may be caused by:

  • Clogs
  • Faulty pipes
  • Blockages

Any roaches (or bugs of any kind) living your sewer may flood up the pipes. As water and waste are forced up, the roaches will go with it.


Rain may cause your sewer to overflow and flood. In this circumstance, any roaches living in the sewer could be motivated to find a new, drier home. If that happens to be a pipe leading to your drain, then you’ll accidentally welcome them to your home.

Fleeing Insecticides

Insecticides are great for killing or deterring cockroaches. However, they may also chase the bugs in the wrong direction. Have you ever:

  • Washed insecticides down the drain?
  • Sprayed insecticides around your yard?
  • Poured insecticides along your foundation?

Then any cockroaches in these areas may be running from the poison – and into your pipes. From there, it’s not difficult to find your drain.

roaches coming out of floor drain

Are Roaches Coming from My Sewer?

Unfortunately, the rumors are true. Cockroaches (and many other bugs) invade, live, breed, and die in sewers. In fact, roaches are so common in sewers that the Journal of Medical Entomology called them “the most important invasive urban pest of sewer environments.” This is especially true in areas with cold temperatures. Sewers provide a warm, moist haven for cockroaches.

Most live there harmlessly, unable to affect your house or apartment. However, as the population grows, the roaches may be forced to expand their territory. You’ll find them invading your yard, your foundation, and coming up your drains.

In urban settings, this is especially true during rainy seasons. Cockroaches like moisture, but can’t live in water for long periods of time. If you have a drain that rarely sees water, look for cockroaches coming up from the sewer line.

However, this isn’t a problem left unchecked by your plumbing. Most homes, apartments, and cities as a whole will design their plumbing to prevent this exact issue. The most important aspect is an elbow joint (or several, depending on the size of your system). The joint will have water in it, creating a barrier. This not only keeps roaches out of your drains, but also gasses from the sewer.

If the water has dried up for whatever reason, the cockroaches (as well as odors) can easily crawl up your drain.

Sewer Roach Vs. Cockroach

You may be familiar with the term “sewer roach.” For some people, it conjures the mental image of a super roach, large and intimidating. Other myths include:

  • Sewer roaches are their own species of cockroach.
  • A lifetime in the sewer has allowed this roach to grow bigger or stronger than household varieties.

Both of these points are entirely incorrect. Sewer roaches and regular cockroaches are one in the same.

The most common sewer roach is the American cockroach. It’s larger than most of its kind, at about 2-3 inches long. This has contributed to the view of it being the “super” version of its average brethren. In actuality, the American cockroach is large for the same reason a German cockroach is small: Its genetics alone, not its environment.

A life filled with ample food will make a cockroach large. However, roaches do not grow indefinitely. You can rest easy that your drains won’t produce exceptional breeds. The only danger of leaving them unchecked is that, like all infestations, they may grow in number.

Do All Types Of Cockroaches Come Up Drains?

Unfortunately, most types of cockroaches will crawl up drains. Of these, the American and German cockroaches are the most common.

  • American cockroaches use drains as places to hide and stay for a while.
  • German cockroaches will move in and out of drains fairly quickly. If they come up, it’s because they’re using it as a road to go somewhere else.

How To Stop Roaches From Coming Up Drains

Not only is it gross and frightening, but it’s also unsanitary to let roaches invade your drains. According to Epidemiology and Infection, cockroaches have the capability to spread bacteria wherever they go. To keep them from scurrying up your pipes and spreading sewer filth, try these solutions:

Find Cracks And Leaks

You can find points of entry by examining your drain pipes. If there are any cracks or holes that a cockroach might get into, you can seal them with caulk or plaster. Even the tiniest crack can become a bigger hole in the future. If the leaks or damage is more severe, you may need to contact a plumber.

Stop Up Drains

Since cockroaches are nocturnal, you can get a stopper or cover for your drains at night. This will cut off their entry point. By denying them food during their active times, they will visit less often.

For the day, you can use a rubber drain cover or a metal drain screen to block their entrance. This prevents the cockroaches from getting in or out of the drain. While it doesn’t solve the problem, it certainly limits the damage of them roaming free.

Fix Leaky Faucets

Standing water in your sink can attract cockroaches. It may only be enough to moisten the drain or sink – but it’s enough.

  • Be sure to check your sink, shower, and other water sources for leaks.
  • You should seal up the crevices or cracks around the faucet and the pipes leading up to it.

Address Condensation

If you notice condensation around your drain pipes, deal with that as well. Since cockroaches like a humid space, the condensation will attract them.

You can use expanding insulation foam to seal spaces around your pipes. This helps keep condensation at a minimum. When you get rid of the water source, roaches will go somewhere else for it.

Move Trash

Is your trashcan under the sink in your bathroom or kitchen? Then it’s wise to move it. The trash will attract roaches to that space. Since there are usually pipes in the area below the sink, this provides an easy invitation.

Clean Up The Surrounding Area

Don’t leave food or trash in your kitchen sink overnight. The smell could attract roaches to come through your pipes and out through your drain. Likewise, be sure to clean up food on the counters, especially overnight. Even leaving food out in containers may provide a tempting scent.

Dry The Sink

Roaches are attracted to any type of humid or wet place. After you do your dishes or clean out the sink, make sure you pat it dry. This will leave no water sources to bring roaches up the drain.

Clean The Pipes Regularly

Be sure to clean your pipes regularly. A build-up of soap, food, or other organic material can coat the walls with ample food sources for a roach. It will also provide texturing on the pipe walls that a roach will use to climb. The smoother, cleaner, and more sanitized the drain is, the more a roach will struggle to invade it.

Did Cockroaches Really Come From My Drain?

If you find roaches near your drain, don’t immediately blame your pipes or sewer. It’s possible the cockroaches didn’t gain access through your drain. Instead, they may have snuck into your home through other means and are now living in your drains.

Why Do Cockroaches Live In Drains?

Roaches typically live in drains that don’t see much use. This may include:

  • A shower in a bathroom only used by guests
  • A sink in your garage
  • A floor drain in your shop

Without water or waste routinely passing down it, the drain instead offers three main advantages to cockroaches.

A Place To Hide

Cockroaches prefer dark, quiet places to nestle themselves away in. This is especially true if they hear activity or loud noises, like a human walking or a pet hunting nearby. The cockroaches may be using your drain as a haven to keep themselves safe.

A Spot To Breed

With the above advantage, you may find more than one roach tucked in your drain. Since cockroaches are prolific breeders, it won’t take long for reproduction to happen.

Cockroach mating isn’t a complicated or time-consuming process. However, both bugs will prefer to be a safe, out-of-the-way place to avoid getting confronted by predators as they reproduce. Your drain could be the perfect romantic getaway.

Somewhere To Lay Eggs

The female may lay eggs inside of your drains. If the pipes are unused, they will serve as isolated spots with firm walls. These are ideal for planting egg sacs, which can grow undisturbed. In floor drains, the pipes might also be covered in mildew, hair, or other organic waste. This can be a food source for baby roaches.

An Area To Sleep During The Day

Cockroaches don’t officially sleep, but they do enter an immobility period. Here, they recoup their energy and are more vulnerable to attacks. A drain serves as a small, secure, dark place to rest.

What To Pour Down The Drain To Stop Roaches

Cockroaches are hard to kill, and pipes are easy to damage. It’s important to choose the right substance to pour down your infested drains. These quick home solutions may not kill roaches, but they will deter the pests. The methods are also safe for your drains, if used in the right quantities.


Dry pipes or drains are an open invitation for cockroaches. If you have floor drains, sinks, or toilets that are rarely used, be sure to:

  • Pour 2 cups of plain water into all of them.
  • Do this at least once a month.

This will help flush out any roaches that are building (or have built) a haven in the drains.

If you live in a hot or dry climate, you’ll need to do this once a week. The pipes and drains will dry much more quickly than in damp, humid climates.

what to pour down your drain to kill roaches

Cooking/Mineral Oil

In combination with the above, you can pour a small amount of cooking or mineral oil down your drain. When properly diluted, this will not affect your septic tank or plumbing.

Instead, it will prevent the water from evaporating as quickly. That’s because the oil will sit on top of the water. This stops the evaporation process from taking place for weeks or even months.

  • Do this every six weeks, up to every two months.
  • This should only be done with water, as oil alone can clog up your pipes.

Boiling Water

If you know the roaches are present, then try pouring boiling water down the drain. This can scorch the cockroaches. In the best event, it will kill then. At the very least, it will wash them down the drain and into the sewer, where they may struggle to return.

The water must be boiling. If it’s simply warm, it may have no effect.

Trap Primer

You can have a trap primer installed by a plumber at each entrance of your water supply. The primer detects when a trap doesn’t have any water left in it. It then releases a small amount of water into the drain to refill the trap. This ensures the drain is never dry and is less likely to attract roaches.

Liquid Trap Seal Primer

For a more DIY solution, you can set up a liquid trap seal primer. This can be found online or in hardware stores in the plumbing section.

  • Pour water down the drain.
  • Pour the odorless liquid primer down.
  • The primer will keep your drain and pipes damp. This may deter roaches for 3 to 6 months, if not longer.

Do Dirty Drains Attract Cockroaches?

A dirty drain will certainly attract cockroaches. As mentioned, they’re attracted to the smell of food and the scent trails of other roaches. These are all open invitations from your drains to the cockroaches:

  • Leaving food in your kitchen sink
  • Leaving hair in your shower drain
  • Leaving soap and toothpaste in your bathroom sink
  • Letting waste or mildew grow inside your drains

However, if you have roaches coming up your drain, this doesn’t automatically mean it’s dirty. Roaches are opportunistic creatures. They may invade your drains because of outside factors that are unconnected to your cleaning routine.

Should I Scrub Clean My Drains?

Manually cleaning your drains might sound like a good idea. While it can cut down on the number of roaches that enter your drain, the act of cleaning will cause other problems.

The scrubbing, steaming, and other actions you use can put bacteria into the air. If the drain is in your kitchen, that bacteria could reach your food or other touchable surfaces.

A bio-cleaner or a foam cleaner is recommended for cleaning out your drains. They both limit the amount of organic compounds and bacteria that spread through the air.

Just make sure to use them on a regular basis. While they may not kill the roaches, they will remove the conditions that make the cockroaches want to be there.

Do I Need An Exterminator To Clean Roaches From My Drain?

So, you have roaches living in your drains, coming out of your drains, or scurrying around unseen. If the home solutions didn’t work, it may feel like you have no choice but to hire a professional exterminator.

If the previous tactics didn’t work, you definitely need a fresh approach. Along with an exterminator, here are heavier-hitting methods.


You can install drain traps into your drain lines to prevent roaches from crawling up them. If placed further down the drain line, traps also stop roaches from coming through the sewer.

The trap valve allows water in, but keeps insects away. Additionally, the trap keeps out gasses and odors, which may attract flies.

Barrier Spray

You can treat the outside of your home with a barrier spray. You or a professional exterminator will apply the spray to the foundation of your home and around any entry points, including drains. Outside the barrier spray, you can place a band of moisture-resistant bait. This will draw the roaches away and then kill them.


An exterminator will have access to a wider range of insecticides. Professional experience can also help them pinpoint exactly where roaches are being attracted. With a combination of the two, you and the expert can apply more precise solutions.

What Not To Pour Down The Drain To Kill Cockroaches

Home solutions are tempting, especially when you have bugs skittering around your feet as you shower.

However, there are certain DIY fixes you should never pour down your drain. These may harm your pipes, while leaving the roaches untouched.

Baking Soda And Vinegar

Baking soda and vinegar produce an unpleasant smell which can deter cockroaches. According to a myth, it also physically harms them. In actuality, it does neither. It won’t harm your pipes, but it may foam around any waste build-up found there. This can eventually lead to clogs.

Even if you follow the mixture with water, it’s not guaranteed to wash all the debris away.


Bleach is highly corrosive. This can damage your pipes if it’s poured directly down the drain. Cockroaches would need to be exposed to a concentrated amount to be harmed. As such, you’d have to choose between (maybe) hurting the roaches and (definitely) hurting your drains.


Borax is often used for cleaning out drains and removing clogs. Since it’s already confirmed as safe for pipes, but is comparable to bleach, many people wonder. Is it great for killing roaches?

Borax cannot harm roaches if they’re soaked or doused in it. Instead, the cockroaches would need to eat the borax. That means you could try pouring straight borax down the drain and hope that the roaches are curious eaters.

However, if you used the solution as prescribed – with hot water – it’ll have no effect. The water will do more damage than borax.


If you want the direct approach, you may consider pouring insecticide or pesticides down your drain. While this can definitely harm the roaches, it’ll have many negative consequences.

You’re just as likely to harm the pipes, your septic tank, and the surrounding soil. This puts toxic chemicals into the water supply and into the environment.

Scaling Chemicals

Scaling chemicals are used to wear down calcium or mineral build-up. While that might take a bite out of the roaches, it’ll also weaken the strength of your pipes. This may create a crack or leak, which lets more roaches in.

Unfortunately, what’s happening in your sewers will largely contribute to the roaches coming up your drains. Cockroaches can come up any drain, but you don’t need to tolerate them. You can ensure that your plumbing has the right elbow joints or water traps. You can also use DIY solutions to keep the roaches away from your internal drains and plumbing.