Cleaning 101: Getting Rid of Drain Flies

Drain flies live in drains, sewers, septic tanks, and soil contaminated with sewage. They feed on the organic matter within pipes and, if given just the chance, will come into your home through access points like kitchen sinks and shower drains. They’re harmless and won’t bite or sting, but since they arrive in large numbers, they can be quite a nuisance.

When you see pests like these in your house, your first reaction is disgust, quickly followed by the question “how do I get rid of these things?” So, here’s how to treat and prevent a drain fly infestation.

How Do You Know if You Have Drain Flies?

Drain flies are small—measuring an eighth of an inch, which is about the size of a fruit fly or a gnat. They are gray or brown in color with light-colored wings, and can leave behind a powdery substance when they are swatted. Drain flies are also fuzzy—covered in hair on their body and wings to give them a furry appearance.

Though these little buggers have very distinct characteristics, they are easy to miss – meaning an infestation could be brewing right under your nose. Usually, infestations start with flies being spotted in small numbers near “access points”. Either resting on walls near a shower or hovering inside sinks for example.

How to Get Rid of Drain Flies

Generally, the best method of pest control for these unwanted guests is to destroy their breeding grounds. To identify where the drain flies are coming into your home, cover any suspected access points with clear packing tape. This should trap any new flies on the tape as they’re trying to come into your home.

Once you know where the drain flies are coming in, keep the access point covered with tape or a drain plug at all times. Then once a day boil a pot of water, uncover the drain and pour the boiling water down it. Recover the drain, and repeat the boiling water method for at least a week until the flies are gone. This method dissolves the gunk buildup that the flies love to feed on and flushes it down the drain.

As for eliminating the flies already inside your home, you can do so with this quick trap! Fill a bowl or jar with equal parts sugar, water and white vinegar, then add 5 to 10 drops of liquid dish soap. Leave the jar next to the sink or shower drain overnight or up to a week until the flies are gone.

Infestation Prevention

Since drain flies feed on the gunk within your pipes, the first step of prevention is keeping drains clean and clear with proper maintenance. Besides cleaning regularly, the best thing you can do to prevent a drain fly infestation is to make sure that you don’t have stagnant water sitting in your pipes. Reducing the effect of stagnant water is as simple as running the water in rarely used showers or drains for about a minute once a week. For good measure, add a ½ cup of salt and a ½ cup of baking soda to the drain and flush down with 1 cup of vinegar. With good preventative measures and a little luck, you’ll never have to deal with drain flies again!

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