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 fly up out of the drain. Was that a gnat? Then you notice more of them zooming around your 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 live all over the U.S., and spread 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 rotten food, they’ll head for your trash can, your overripe fruit and the kitchen drain, which is packed with moisture and small bits of food. Occasionally you’ll watch them come up out of the drain. This can be especially likely if you have a somewhat clogged sink or disposal that empties slowly. This maintains more moisture and food waste that appeals to these insects and allows them to thrive and reproduce. 

How Bad Are They? 

When fruit flies move from a dirty surface to a clean one, they bring germs with them. This can include listeria, salmonella and even E. coli. All of these bacteria can cause serious 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 kills bacteria. Don’t reuse sponges that can attract, retain and transfer germs. It’s better to use paper towels and throw them out. 

Bug sprays can eliminate the adult fruit flies but won’t destroy the eggs. And you most likely don’t want to spread insecticide all around your kitchen. Instead, pour boiling water down your drain. Before bed, close 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 try, all with a jar: 

  • Wine—Place an ounce of wine into the jar. Add a hole in the lid so the fruit flies can access the wine. You can also have a funnel or paper cone in the place of a lid. 
  • Spoiled fruit—Same as above, but with 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 as well, which makes it more difficult for flies to escape. 
  • Yeast—Pour in two or three ounces of water, one packet of activated dry yeast along with a teaspoon of sugar. 

To minimize bringing in fruit flies: 

  • Wash your produce as soon you bring it home. Sometimes they can contain fruit fly eggs or larvae. 
  • Refrigerate whenever you can. 
  • Don’t keep overripe produce in your kitchen. 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 open, put in some well-fitted screens. 

If the above methods haven’t eliminated your fruit fly issue, there might be something wrong with your p-trap. That’s the section of your drain pipe bent in a u shape to capture water and prevent foul air from wafting up into your home. It also keeps 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 problem. Run the water and search below for a leak. If you spot one, get it fixed right away. Leaky pipes can encourage mold and structural problems with your home. 

You should also hire a plumber if your kitchen sink or garbage disposal is draining more slowly than usual. This problem not only helps attract fruit flies, but over time the sink drain can entirely clog and become useless. The Service Experts Heating, Air Conditioning & Plumbing plumbing team has the tools, experience and knowledge to identify the problem and fix it quickly. We employ a video drain inspector to clearly see what’s occurring within 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 clear leaky pipes. 

If you need any sort of plumbing service at all, contact 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 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.