Why Are There Fruit Flies in My Kitchen Sink Drain?

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

Why Are They Here?

Fruit flies survive all over the U.S., and grow 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.” As they’re lured by moisture and rotten food, they’ll frequently appear in your trash can, your overripe fruit and the kitchen drain, which is full of moisture and small chunks of food. Occasionally you’ll see them come up out of the drain. This can be especially likely if you have a partly clogged sink or disposal that clears out slowly. This retains more moisture and food particles that attracts these insects and enables them to thrive and reproduce.

How Bad Are They?

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

What Can I Do About Them?

Because of this bacterial risk, keep your surfaces clean at all times. Use a kitchen surface cleaner that eliminates bacteria. Don’t reuse sponges that can attract, retain and exchange germs. It’s cleaner to use paper towels and throw them out.

Bug sprays can eliminate the adult fruit flies but won’t kill the eggs. And you most likely don’t want to apply insecticide all around your kitchen. Instead, put boiling water into your drain. Before bed, block off your drains with clear packing tape. In the morning, you should see some fruit flies stuck to it.

Here are other barriers you can also use, all involving a jar:

  • Wine—Put an ounce of wine inside the jar. Put a hole in the lid so the fruit flies can get in. You can also have a funnel or paper cone rather than a lid.
  • Spoiled fruit—Same as above, but with rotten fruit rather than 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 get away.
  • Yeast—Put in two or three ounces of water, one packet of activated dry yeast and a teaspoon of sugar.

To prevent bringing in fruit flies:

  • Clean your produce as soon you bring it home. Sometimes they can have fruit fly eggs or larvae.
  • Refrigerate as soon as you can.
  • Avoid keeping old produce in your home. Buy only what you’re most likely to eat.
  • Empty your kitchen trash often, and keep it closed.
  • Keep your surfaces clean and disinfected.
  • If you prefer to keep windows up, make sure they have well-fitted screens.

If the listed methods haven’t taken care of your fruit fly infestation, there may be an issue with your p-trap. That’s the area of your drain pipe bent in a u shape to capture water and stop foul air from drifting up into your home. It also stops flies from living in your pipes and flying up from the drain. If your pipe has a leak and is missing a water seal, this can lead to a fruit fly infestation. Run the water and look below for a leak. If you spot one, get it fixed quickly. Leaky pipes can lead to mold and structural problems with your home.

You should also call a plumber if your kitchen sink or garbage disposal is draining more slowly than usual. This problem not only helps breed fruit flies, but over time the sink drain can fully clog and become inoperable. The Service Experts Heating & Air Conditioning plumbing team has the equipment, experience and expertise to diagnose the problem and fix it quickly. We utilize a video drain inspector to plainly see what’s occurring within the pipes, and a variety of methods to clean them, depending on the type and severity of the blockage. If the problem is the garbage disposal, we can repair or replace it at a price you can afford. We also resolve leaky pipes.

If you are looking for 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 comfortable. 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.