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 see a small creature fly up out of the drain. Was that a gnat? Then you see more of them buzzing around your kitchen. These aggravating little guys are actually fruit flies. And if you’re wondering 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 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 drawn to moisture and rotten food, they’ll head for your trash can, your overripe fruit and the kitchen drain, which is full of moisture and tiny bits of food. Sometimes you’ll notice them fly up out of the drain. This can be notably bad if you have a partially clogged sink or disposal that clears out slowly. This maintains 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 might include listeria, salmonella and even E. coli. All of these bacteria can result in serious cases of food poisoning.

What Can I Do About Them?

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

Bug sprays can kill the adult fruit flies but won’t get rid of the eggs. And you likely don’t want to spray insecticide all around your kitchen. Instead, pour boiling water in your drain. Before bed, close off your drains with clear packing tape. In the morning, you can see some fruit flies trapped to it.

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

  • Wine—Add an ounce of wine in the jar. Make a hole in the lid so the fruit flies can access the wine. You can also use a funnel or paper cone in the place of a lid.
  • Old fruit—Same as above, but using 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 more difficult for flies to escape.
  • Yeast—Add two or three ounces of water, one packet of activated dry yeast as well as a teaspoon of sugar.

To avoid encouraging fruit flies:

  • Wash your produce as soon you bring it home. Sometimes they can possess fruit fly eggs or larvae.
  • Refrigerate as soon as you can.
  • Avoid keeping spoiled 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 prefer to keep windows up, install well-fitted screens.

If the above methods haven’t eliminated your fruit fly issue, there could also be an issue with your p-trap. That’s the area of your drain pipe bent in a u shape to trap water and keep foul air from wafting up into your home. It also prevents flies from surviving in your pipes and flying up from the drain. If your pipe has a leak and is missing a water seal, this can create a fruit fly infestation. Run the water and look below for a leak. If you see one, get it fixed promptly. Leaky pipes can cause mold and structural problems with your home.

You should also hire 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 completely clog and become unusable. The Service Experts Heating & Air Conditioning plumbing team has the equipment, experience and knowledge to diagnose the problem and fix it quickly. We utilize a video drain inspector to obviously see what’s occurring in the pipes, and a number 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 handle leaky pipes.

If you are looking for any sort of plumbing service at all, call 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.