Water Bug vs. Cockroach: What’s the Difference?

Often mistaken for cockroaches or palmetto bugs, water bugs are actually aquatic insects that thrive in water. Not only can water bugs leave painful bites, but they can spread contaminants that cause diarrhea and food poisoning. We’ll help you identify a water bug, explain how to get rid of an infestation, and leave you with tips to prevent water bugs from entering your home in the future.

What is a water bug?

A true water bug is an aquatic insect classified under the order Hemiptera. The most common species of water bug is the giant water bug, also known as the electric light bug or alligator tick. Other types of water bugs include water boatmen, water scorpions, water striders, pond skaters, and water spiders. Two species of cockroaches that are commonly confused with a water bug are the American cockroach and the Oriental cockroach.

What does a water bug look like?

A water bug is a flat, oval-shaped creature that’s typically black, tan, or dark brown. Most water bug species are relatively large and are at least 3.8 cm long. Water bugs have legs that help them paddle through water and stay afloat and wings that help them fly. They also have clawed front feet, a piercing mouth, and a pointed beak to capture prey.

Where do water bugs live?

Water bugs mainly live in water, but they can be found around other water sources, like pools and ponds, and in trash cans, sewers, basements, and other damp areas at or below ground level. While water bugs typically live outside, they migrate indoors for warmth when the temperature drops. They can enter your home through cracks and holes in your walls and foundation.

What do water bugs eat?

Unlike cockroaches, which eat just about anything and everything, water bugs prey on insects, small fish, and other small animals with their proboscis, or biting mouthpiece. They use this part to inject a powerful enzyme that liquefies the insides of their prey to make feeding easier.

Can water bugs bite?

Water bugs may bite humans, but only if provoked or if their habitat is disturbed. Their bites can be painful, but seldom harbor an allergic reaction. Common symptoms of a water bug bite include:

• Itching
• Red bumps
• Mild burning sensation
• Pulsating pain

How to treat water bug bites

If you’ve been bitten by a water bug, treat the bite by following these steps:

1. Wash the affected area with warm water and soap.
2. Make a homemade paste of one part water and one part baking soda and apply it to the bite area. Leave the paste on for an hour and then rinse it off with cold water.
3. If experiencing itchiness, dip a cotton ball in lemon juice and gently dab it on the bite. You may also apply an over-the-counter hydrocortisone cream to reduce itching and inflammation. Be sure to read and follow all instructions on any over-the-counter prescription cream or gel.
4. Use aloe vera gel or an ice pack to reduce swelling and alleviate redness.

How to get rid of a water bug infestation

Because water bugs can spread quickly and survive for up to two weeks without water, it’s best to get rid of them as quickly as possible. Here are some methods of getting rid of waterbugs.

• Use borax or boric acid—These natural elements will destroy a water bug’s digestive tract, killing them from the inside out. Sprinkle a thin dusting of borax or boric acid in your basement, under sinks, and other areas where you’ve seen water bugs. Since boric acid and borax can be toxic if ingested, be sure to keep them away from food prep areas, children, and pets.
• Spray essential oils—Water bugs, like most insects, hate the smell of essential oils. Mix a few drops of citronella essential oil with water and pour the solution into a spray bottle. You can also use peppermint oil as another safe and natural pesticide option. Spray areas where you’ve seen water bugs, in addition to all sink and tub drains around your home.
• Make a homemade vinegar spray—Mix together one part vinegar and one part water and pour the solution into a spray bottle. Use this solution twice a day and spray areas where you’ve seen water bugs.
• Sprinkle food-grade diatomaceous earth—Diatomaceous earth can be used in the home and around your garden to get rid of water bugs. This substance is an effective insecticide as it has a direct impact on the water bug’s outer shell and destroys the protective covering.
• Create a homemade alcohol solution—Alcohol will dry out water bugs and the moist environment they hide in. Dilute a cup of alcohol with water and pour the solution into a spray bottle. Target areas where you’ve seen water bugs frequent.
• Use an algaecide in your pool—Algaecide can eliminate the food supply for water bugs. Use pool-shocking chemicals to shock your pool. Then, use the algaecide following the instructions on the packet and vacuum the pool with a pool vacuum cleaner. Repeat as often as necessary.
• Call in a professional exterminator to eliminate the problem—To ensure you’ve successfully removed all water bugs from your house, hire a pest control professional. You’ll likely have the option of choosing between natural and chemical methods to eradicate the water bug infestation.

Preventing a water bug infestation

After getting rid of the water bugs in your home, take preventative steps to stop more from invading your property.

• Deep clean your house; make sure there are no areas with standing water, clean behind furniture, and disinfect your kitchen and bathrooms.
• Seal any cracks or holes in your home’s exterior with caulk.
• Since water bugs are attracted to water, fix leaky pipes and faucets.
• Keep food stored in airtight containers to prevent attracting water bugs to your home.

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