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 notice a small creature buzz up out of the drain. Is that a gnat? Then you notice more of them zooming around your kitchen. These irritating little guys are actually fruit flies. And if you’re wondering how they got in there and what can 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.” Since they’re attracted to moisture and rotting food, they’ll often end up in your trash can, your old fruit and the kitchen drain, which is packed with moisture and tiny pieces of food. Sometimes you’ll see them come up out of the drain. This can be particularly likely if you have a partly clogged sink or disposal that empties slowly. This preserves more moisture and food waste that draws these insects and lets them thrive and reproduce. 

How Bad Are They? 

When fruit flies move from a dirty surface to a clean one, they carry germs with them. This may 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? 

Due to this bacterial exposure, keep your home’s surfaces clean at all times. Use a kitchen surface cleaner that eliminates bacteria. Don’t reuse sponges that can soak up, retain and exchange germs. It’s best to use paper towels and dispose of them. 

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

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

  • Wine—Add an ounce of wine into the jar. Put a hole in the lid so the fruit flies can access the wine. You can also utilize a funnel or paper cone in the place of a lid. 
  • Old fruit—Same as above, but with rotten fruit in place of wine. 
  • Apple cider vinegar—Same as above but using apple cider vinegar. 
  • Apple cider vinegar and dish soap—Same as above with dish liquid added, which makes it more difficult for flies to get away. 
  • Yeast—Put in two or three ounces of water, one packet of activated dry yeast along with a teaspoon of sugar. 

To avoid encouraging fruit flies: 

  • Clean your produce immediately after bringing it home. In some cases they can have fruit fly eggs or larvae. 
  • Refrigerate whatever you can. 
  • Try not to keep old produce in your house. Buy only what you’re going 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 listed methods haven’t taken care of your fruit fly problem, there might be something wrong with your p-trap. That’s the area of your drain pipe bent in a u shape to capture water and prevent foul air from wafting up into your home. It also prevents flies from hiding in your pipes and flying up out of the drain. If your pipe has a leak and is missing a water seal, this can produce a fruit fly infestation. Run the water and search below for a leak. If you see one, get it fixed promptly. Leaky pipes can encourage mold and structural problems with your home. 

You should also contact 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 completely clog and become inoperable. The Service Experts Heating, Air Conditioning & Plumbing plumbing team has the tools, experience and expertise to diagnose the problem and resolve it promptly. We use a video drain inspector to plainly see what’s occurring inside the pipes, and multiple methods to clean them, depending on the type and intensity of the blockage. If the problem is the garbage disposal, we can repair or replace it at a price you can afford. We also fix leaky pipes. 

If you need any sort of plumbing service at all, call the professionals at Service Experts Heating, Air Conditioning & Plumbing. Whether we’re warming, cooling or making the water run, we take great pride in keeping our customers satisfied. 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.