Why Are There Fruit Flies in My Kitchen Sink Drain?

Has this ever happened to you? You’re washing a dish in the kitchen sink and watch a small creature fly up out of the drain. Was that a gnat? Then you see more of them flying around the kitchen. These aggravating little guys are actually fruit flies. And if you’re wanting to know how they got in there and what may be done about them, you’re in the right place.

Why Are They Here?

Fruit flies survive all over the U.S., and mate quickly. According to WebMD, “An adult female fruit fly can lay up to 2,000 eggs on the surface of anything that's moist and rotting. Within 30 hours, tiny maggots hatch and start to eat the decayed food. Within two days, they're all grown up and ready to mate.” Because they’re attracted to moisture and decomposing food, they’ll often end up in your trash can, your overripe fruit and the kitchen drain, which is full of moisture and tiny chunks of food. In some cases you’ll watch them come up out of the drain. This can be notably frustrating if you have a partially clogged sink or disposal that drains slowly. This retains more moisture and food waste that draws these insects and allows them to thrive and reproduce.

How Bad Are They?

When fruit flies transfer from a dirty surface to a clean one, they lug germs with them. This can include listeria, salmonella and even E. coli. All of these bacteria can result in severe cases of food poisoning.

What Can I Do About Them?

Owing to this bacterial risk, keep high-traffic surfaces clean at all times. Use a kitchen surface cleaner that eliminates bacteria. Don’t reuse sponges that can absorb, retain and transport germs. It’s best to use paper towels and throw them out.

Bug sprays can kill the adult fruit flies but won’t destroy the eggs. And you probably don’t want to apply insecticide all around your kitchen. Instead, pour boiling water in your drain. Before bed, close up your drains with clear packing tape. In the morning, you should see some fruit flies stuck to it.

Here are other ideas you can also attempt, all involving a jar:

  • Wine—Pour an ounce of wine in the jar. Add a hole in the lid so the fruit flies can enter. You can also utilize a funnel or paper cone instead of a lid.
  • Spoiled fruit—Same as above, but use rotten fruit in place of wine.
  • Apple cider vinegar—Same as above but with apple cider vinegar.
  • Apple cider vinegar and dish soap—Same as above with dish liquid in addition, which makes it much harder for flies to break free.
  • Yeast—Pour in two or three ounces of water, one packet of activated dry yeast as well as a teaspoon of sugar.

To minimize bringing in fruit flies:

  • Wash your produce immediately after bringing it home. Sometimes they can possess fruit fly eggs or larvae.
  • Refrigerate whatever you can.
  • Don't keep old produce in your house. Buy only what you’re likely to eat.
  • Empty your kitchen trash often, and keep it closed.
  • Keep your surfaces clean and disinfected.
  • If you want to keep windows raised, make sure they have well-fitted screens.

If the listed methods haven’t taken care of your fruit fly infestation, there could also be something wrong with your p-trap. That’s the part of your drain pipe bent in a u shape to capture water and keep foul air from wafting up into your home. It also stops flies from hiding in your pipes and flying up from the drain. If your pipe has a leak and has no water seal, this can lead to a fruit fly infestation. Run the water and check below for a leak. If you see one, get it fixed quickly. Leaky pipes can cause mold and structural problems with your home.

You should also call a plumber if your kitchen sink or garbage disposal is draining slower than usual. This problem not only helps encourage fruit flies, but over time the sink drain can entirely clog and become unusable. The Service Experts Heating & Air Conditioning plumbing team has the tools, experience and know-how to identify the problem and solve it right away. We utilize a video drain inspector to clearly see what’s happening inside the pipes, and a number of methods to clean them, depending on the type and intensity of the blockage. If the problem is a garbage disposal, we can repair or replace it at a price you can afford. We also clear leaky pipes.

If you want any sort of plumbing service at all, get in touch with the professionals at Service Experts Heating & Air Conditioning. Whether we’re warming, cooling or making the water run, we take great pride in keeping our customers happy. With more than 4,000 team members, we can deliver and innovate better than anyone. Our can-do family attitude helps us get the job done on time, and right—the first time.

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