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Like the legendary sewer gators of New York City, the Arizona sewer roach strikes a note of fear and horror in the hearts of many Arizonians. Unlike those fictional reptiles however, sewer roaches are a real and serious problem in areas like Pima and Maricopa county.

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A handful of easy-to-use products can solve most cockroach problems.

Read on to learn more about the problem and how to get rid of sewer roaches in your home.

Remember, when using insecticides, the label is the law—read and follow the instructions carefully, not only for your own safety, but to make sure each treatment is as effective as possible.

Sewer Cockroaches: Stuff of Nightmares

Illustration of an American sewer cockroach in a sewer, with diagram of sewer line that enters home

The Arizona sewer roach—a disgusting, trouble-making, knee-quaking monster of a bug, emerges from the muck of sewers to invade homes and apartments across the state.

They’re a homegrown nightmare, or so some think given that few people outside the state have ever heard of them. But in fact they’re not.

Sewer roaches, as it turns out, are the very same American cockroach species that infests numerous other regions across the country. Arizonians have simply given them a particularly descriptive (and disgustingly accurate) nickname—which only they tend to use.

Like everybody else who has to deal with American roaches, Arizonians really want to get rid of them, which we’ll shortly show you how to do.

Fun fact: If you’re familiar with sewer-dwelling “water bugs,” you already know all about sewer cockroaches—it’s just another nickname for the same species of cockroach.

What Sewer Roaches Look Like

Comparative illustration of an Arizona Sewer Roach, adult, nymph, and egg case

Sewer roaches are generally 1 ½ to 2 inches long and are relatively flat. They have reddish-brown to dark-brown bodies, six legs and two long antennae.

Their hard exoskeletons make them difficult to squish and allow them to slip through small crevices. On their backs they carry a pair of long, transparent wings. Though big bugs, they’re fast runners, and remarkably good at surviving the ways that people try to kill them.

And by the way… do sewer roaches fly?

When you ask an Arizona native for advice on sewer roaches, the response you don’t want to hear is:

“Have they flown at you yet?”

Yep, these creatures of the abyss can unfold those long wings on their backs and fly—for a few feet, at least. Though they usually run away when spotted, there’s a chance they’ll fly straight toward you! (They’re only trying to escape through the door behind you, but still…)

Baby sewer roaches

Baby sewer roaches’ tiny size makes them no less dangerous. Baby cockroaches are only about 1/4 inch long but generally the same reddish-brown color as the adults. They can appear white or gray just after they’ve molted, though. If the sewer roaches have started reproducing, it’s time to act fast.

Why You Keep Finding Sewer Roaches in Your Bathroom, and Why You Have to Get Them Out

Illustration of two American sewer roaches coming up a bathroom sink drain

Why and how they come inside

A sewer roach’s preferred habitat is outside, among the wet, rotting material on forest floors and in alleyways and sewers. Unfortunately, heavy rain or a backed-up sewer line can cause these bugs to climb up sewer pipes, drain pipes, and up through the sink or floor drain.

Indoors, they look for damp, dark, moist areas—kitchen cabinets, utility closets, basements, etc. Since your bathroom is directly connected to the sewer system, it’s often where homeowners first start noticing roaches and cockroach infestations.

Vacant rooms are especially at risk because, when the water’s turned off and the pipes are dry, it’s easy for sewer roaches to crawl up through the drains and start laying eggs in the nearest cracks and crevices.

Tip: Even sewer cockroaches can’t come up through the toilet. While they can hold their breath for up to 40 minutes, they can’t swim very well. So long as your toilet is filled with water, you’re safe on that seat, at least.

Why you really need to get them out

The reason sewer cockroaches live shamelessly in the sewers is the same reason you never want them crawling around your house: they eat down there.

Think about all of the things that find their way to sewers. Beyond all the “number one’s” and “number two’s,” they’re feeding on heaps of sludge and grease, water overflow, and more.

When they finally do come up into your home, they don’t leave all those dangerous germs, bacteria, and allergens behind. They bring it all with them, depositing it onto everything they touch.

So if you have a sewer roach problem, you really need to take care of it, especially if it’s getting worse.

How to Get Rid of Sewer Roaches Step 1: Killing Them

Illustration of a dead sewer roach surrounded by methods of killing them

Now that you know how to identify them and why they’re not a pest you want to keep around, how do you get rid of sewer roaches, possibly for good? The good news is you can, but you’ll need the right tools… and a little patience.

Here are the tools and approaches you can use for a basic indoor plan:

  1. Glue traps to find their entry points
  2. Gel bait to kill the sewer roach colony
  3. Drain treatments: bleach, foam and more
  4. How to get rid of sewer roaches naturally

Suggested Products

Remember, when using insecticides, the label is the law—read and follow the instructions carefully, not only for your own safety, but to make sure each treatment is as effective as possible.

To Find Their Hiding Spots and Kill Them Fast When You Have Just a Few

Exterminator’s Choice Sticky Glue Traps

Used to measure and monitor a cockroach infestation and provide some supplemental control.

BASF PT P.I. Contact Insecticide

P.I. is a pyrethrin-based spray insecticide that kills roaches fast. Best when used as a supplement to other treatments, it’s not inexpensive, but far more effective than off-the-shelf sprays.

To Kill Them Inside Your Home When You Have a Serious Problem

Rockwell Labs CimeXa Dust Insecticide

CimeXa is an effective indoor crack and crevice treatment. For best results, use alongside Advion Gel Bait and Gentrol IGR.

HARRIS Diatomaceous Earth Powder Duster

Insecticidal dusts like CimeXa work best when applied with a duster tool. This inexpensive diatomaceous earth duster works fine with CimeXa, Delta Dust, and other recommended dusts.

Syngenta Advion Cockroach Gel Bait

Advion first poisons the roaches that eat it, then others in a secondary kill. For the most effective indoor treatment, combine with CimeXa insecticidal dust and Gentrol IGR.

Gentrol Point Source IGR

Gentrol is an insect growth regulator (IGR) that interferes with roach reproduction. It’s most effective used alongside Advion Gel Bait and CimeXa insecticidal dust.

To Kill Them Outdoors Before They Have a Chance to Get Inside

Bayer Polyzone Suspend Insecticide

When used on exterior foundations, entries, and walls, Suspend insecticidal liquid stops outdoor roaches before they get in. It requires a separate sprayer (see below), and works best alongside a granular outdoor bait like Intice and an outdoor crack and crevice treatment like Delta Dust.

Chapin 1 Gallon Multi-Purpose Sprayer

Liquid pesticides require a separate sprayer. This inexpensive pump sprayer works fine for smaller jobs.

InTice Perimeter Insect Control Bait Granules

InTice is a granular bait that kills roaches outdoors and in spaces like your garage or attic. Used alongside a spray treatment like Bayer Suspend and a crack and crevice treatment like Delta Dust, it can protect the entire perimeter of your home.

Delta Dust Insecticide Dust

Waterproof and long-lasting, Delta Dust is a crack and crevice treatment effective in high-moisture areas such as attics, exterior walls, and plumbing lines. Delta Dust is regulated and unavailable in some areas.

1. Place glue traps to find their entry points

To stand a chance against an invasion of sewer cockroaches, you have to know where they’re coming from. Place sticky glue traps in corners and along the walls in different rooms. Check which traps have caught more roaches to narrow down your targeted area.

Besides kitchen sinks, bathroom sinks and shower drains, sewer roaches’ most likely entry points are heating or utility vents, plumbing penetrations and cracks in exterior walls.

2. Apply a gel bait to kill a sewer roach colony inside

A good cockroach gel bait is an unmatched sewer roach killer. Gel bait kills cockroaches after they’ve eaten it and returned to their nest. There, other cockroaches will be exposed to the toxins and that’s where gel bait really shines.

Its insecticide is strong enough to kill those roaches that eat it secondhand—and even third-hand! A few drops of gel bait can do serious damage to a sewer roach infestation.

3. Treat your drains

Cities might try to treat the sewer systems for cockroaches but it’s virtually impossible to eliminate these pests city-wide. Protect your home or apartment by regularly cleaning and treating your drains.

Use a foam cleaner—cautiously

Use a foam cleaner or similar product to remove traces of food and grease that could attract roaches. Read labels ahead of time for cautions and proper use.

Use bleach—cautiously

Bleach not only cleans and disinfects your drains, but kills roaches hiding there.

Avoid bleach if you have a septic system, and never combine it with ammonia, vinegar, rubbing alcohol, acetone, other cleaners, or pesticides (which combined with bleach could harm you). To treat a drain with bleach, pour 1/4 to 1/2 cup into the drain and plug it. Let it sit in the drain trap for 30 minutes, then flush thoroughly with water.

Use water—liberally

This is the easiest, and possibly most effective trick of all. Running water regularly down your drains keeps drain traps filled, and prevents roaches from crawling up.

4. Kill Sewer roaches naturally

If you’d prefer to avoid chemicals, there are two all-natural, easy-to-use options: borax and diatomaceous earth (DE).

Note: While natural, both these products are irritants and should not be inhaled.

Borax mixed with a little powdered sugar acts just like gel bait, attracting sewer roaches and then killing them. It’s easy to find in the laundry aisle at many stores. For more tips, check out our overview of the best borax recipes for roaches.

DE is another effective sewer roach killer. Roaches don’t even have to eat it! Just walking through DE kills cockroaches by dehydrating them. It’s virtually non-toxic, too!

5. Call Professional Pest Control

If you’re at all worried about a sewer roach infestation getting out of hand, call your local pest control company. You can discuss treatment options and learn more about what might be causing the problem from a visit by a professional.

How to Get Rid of Sewer Cockroaches Step 2: Preventing Them from Coming Back

The first step is eliminating sewer roaches that have already invaded. The next, equally important step is keeping them away.

Here’s how to prevent sewer roaches:

1. Block the drains.

Before you do anything else, buy some drain covers for every sink and bathtub in the house. Your drain stops don’t have to be anything fancy. They just have to feature holes small enough that roaches can’t fit through.

2. Check the perimeter of your house and seal openings.

Pipes collect condensation and that moisture can attract sewer roaches on the ground outside. If there are gaps where these pipes come into your house, seal them with expanding foam or steel wool. Fill other cracks and holes you spot in the walls, doors and windows, and foundation, too.

3. Fix leaks and dripping faucets.

Before sewer roaches make themselves comfortable sipping from that pesky dripping sink at night, repair the leak (and save yourself money on the water bill). Stuff some of that leftover steel wool into the overflow holes in your bathroom sinks, too.

4. Wash the dishes and clean the garbage disposal.

Maybe the sewer roaches didn’t climb up through the pipes but are simply dipping into them for a snack. Your garbage disposal collects a ton of grease and food particles over time—a veritable silver platter for a hungry roach. Make sure you’re cleaning it regularly.

Dirty dishes can feed these pests, too. Washing dishes and giving the counters and floors a quick wipe-and-sweep each day is a simple habit that reduces the risk of attracting cockroaches.


Now that you’ve learned how to get rid of sewer roaches and picked up some tips for preventing them, you’re ready to give yourself the pest-free home you deserve.

Go for it!

Written by Andrew Martin. Reviewed by James Miksanek, PhD.

Disclaimer: This page is strictly for informational use. When using insecticides, keep in mind—the label is the law. Insecticides should be applied correctly and safely when needed, and according to the laws of your state or country.

Andrew Martin

Andrew Martin


Andrew writes for, and along with his daughter, publishes Cockroach Facts. You can read more about him here.

James Miksanek, PhD

James Miksanek, PhD.

Science Editor

James is an entomologist and adjunct professor of biology. His background is in biological control, and he has a passion for ecology and environmental science. His research has addressed a variety of topics including pest control and the management of invasive species. You can learn more about our contributors here.


  1. Cockroaches Fact Sheet. Sacramento Area Sewer District. Retrieved from–for_website_0.pdf?1579220772
  2. Reichardt, Klaus (2017) A Wet Drain Keeps the Cockroaches Away. Cleaning & Maintenance Management. Retrieved from
  3. Lupo, Lisa (2017) Cockroaches in Drains. PCT Magazine. Retrieved from
  4. Vector (Roach) Control Program. Pima County. Retrieved from

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