How to Get Rid of Gnats in Your Drains

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Of all the rooms in our homes, the kitchen is one that many people seek to keep as clean as possible.
Image Credit: NARIN EUNGSUWAT/iStock/GettyImages

Of all the rooms in our homes, the kitchen is one that many people seek to keep as clean as possible. After all, the food that we eat and the dishes that we eat off of are all prepared and stored in that room, and the last thing most of us want to deal with is bugs in such an important space.

While some infestations are more troublesome to get under control than others, getting rid of gnats is relatively simple. If you discover gnats in your sink drains, you'll want to start by cleaning the immediate area, removing old food and food scraps and flushing your drain out with a chemical or natural gnat-removing solution.

Why Gnats Live in Drains

With a great big world to fly around in, you may wonder why gnats would choose to hang around your sinks and drains. For gnats, sinks, drains and garbage disposals may contain sweet morsels of food and sustenance that certain bugs are highly attracted to. Gnats also tend to seek out living environments that are warm and moist, which makes the dark recesses of sink drains a great option for them. While it will take some effort to rid your drain of these bugs, eliminating them from your home is fairly easy by taking just a few simple steps.

If gnats and fruit flies can be seen hovering around piles of dirty dishes, old garbage or fruit that's quickly on its way to becoming expired, the first thing you should do is clean up these messes and throw away anything that you won't use. Keeping your kitchen spaces clean and free of old fruits and vegetables, soda and beer cans or other sugary substances should go a long way in reducing the number of gnats you find in your home and may even eliminate the problem.

If you notice that gnats are coming up for air from inside your sink drains, however, you'll need to treat those bugs by targeting the source — the inside of your sink's pipes. For anyone unsure where the gnats are coming from, placing a piece of duct tape over your drain before you go to sleep at night will trap any bugs that try to exit from the opening and will confirm the place they're entering your home through.

Chemical Solutions for Gnats

If you have a gnat infestation that you're looking to eliminate, chemical products like sprays and liquids offer a quick and effective solution to your troubles. Contact aerosol sprays, which include chemical insecticides like pyrethrins, resmethrin, d-trans and tetramethrin, can be applied around the affected area once a week for about one month. When you use bug spray, however, take care to avoid spraying directly onto food (including pet food,) dishes or anything else that may come into contact with your mouth as they can be harmful when ingested in large amounts.

If you have bleach on hand, you can tackle your gnat issue by pouring a solution down your drain, just be sure to dilute your bleach with plenty of water — a 1/2 cup of bleach mixed with 1 gallon of water is a safe measurement. Using bleach to treat gnats in your drain isn't recommended if you have a garbage disposal, however, as it may harm the disposal's mechanical functions. If this is the case, opt out of using any chemicals and treat your infestation with natural remedies made at home.

DIY Alternatives

To remove gnats in the sink the natural way, you can treat the inside of your sink pipes by pouring a mixture of dish soap, baking soda, vinegar and water into your drain, which usually kills gnats instantly. For a deeper clean, you can create a treatment using only baking soda and vinegar. Start by adding a couple of tablespoons of baking soda followed by about 1 cup of white vinegar down your drain, which will cause a chemical reaction that will loosen up grime inside of the pipes. Let this mixture sit for about two hours before running warm water until all of the ingredients have rinsed down the drain.

In addition to running a liquid solution down your drain or treating it with a stronger cleanser, you can wipe down your pipes by running a scrubbing brush with a long handle as far down into the drain as you can, which may help remove stuck-on food particles from the inside of your pipes. This can not only reduce waste that gnats are attracted to, but it can also prevent gnat larvae from reproducing as they'll have nothing to feed on, which will ensure that no new gnats enter your home.

Drain Fly Trap

If you don't wish to clean out your drain pipes, you can create a drain fly trap using just a few inexpensive items that you may already have lying around your house. One easy trap to set out involves nothing more than a cup, some vinegar or red wine and a bit of dish soap. To make, simply add a bit of wine or vinegar to a glass along with a small squirt of dish soap – the vinegar or wine will attract the gnats and the dish soap will prevent them from flying back out of the glass once they've fallen into the liquid.

If you have old fruit in your home that seems to be attracting gnats, you can put it to good use as trap bait. To create this trap, take a bit of rotting fruit or an old vegetable and mash it up in a deep bowl or glass. Then, cover the bowl with saran wrap and poke a few holes into the top of the plastic, which will prevent the gnats from flying back out after they've wandered in to get a bit of the old food.

Gants, like some other types of bugs, are highly attracted to bright colors and lights (you may have noticed bugs hanging around your porch lights in the evening). To attract gnats to your DIY bug trap, apply brightly colored insect strips or tape around the opening of the trap. Electric bug zappers can also work to keep gnat infestations to a minimum and may be helpful when dealing with large amounts of bugs.


Krissy Howard is a NY-based freelance writer who specializes in creating content regarding pet care, skin care, gardening, and original humor. Her work has appeared on Reader's Digest, Hello Giggles, and Reductress.

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