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 see a tiny creature fly up out of the drain. Was that a gnat? Then you notice more of them zooming around your kitchen. These annoying little guys are actually fruit flies. And if you’re asking how they got in there and what can be done about them, you’re in the right place. 

Why Are They Here? 

Fruit flies live 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 rotting food, they’ll often end up in your trash can, your old fruit and the kitchen drain, which is full of moisture and little bits of food. In some cases you’ll see them fly up out of the drain. This can be especially likely if you have a partially clogged sink or disposal that clears out slowly. This retains more moisture and food particles that attracts 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 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 absorb, retain and transfer germs. It’s best to use paper towels and throw them away. 

Bug sprays can kill the adult fruit flies but won’t kill the eggs. And you probably don’t want to apply insecticide all over your kitchen. Instead, put boiling water into 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 traps you can also try, all involving a jar: 

• Wine—Put an ounce of wine into 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 instead of a lid. 

• Rotten fruit—Same as above, but use rotten fruit instead of wine. 
• Apple cider vinegar—Same as above but you’ll use apple cider vinegar. 
• Apple cider vinegar and dish soap—Same as above with dish liquid added, which makes it more difficult for flies to escape. 
• Yeast—Put in two or three ounces of water, one packet of activated dry yeast as well as a teaspoon of sugar. 

To avoid bringing in fruit flies: 

• Wash your produce immediately after bringing it home. In some cases they can contain fruit fly eggs or larvae. 
• Refrigerate whatever you can. 
• Don’t keep old produce in your home. 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 like to keep windows raised, make sure they have well-fitted screens. 

If the above methods haven’t eliminated your fruit fly problem, there could also be a problem with your p-trap. That’s the area of your drain pipe bent in a u shape to trap water and stop foul air from drifting up into your home. It also keeps flies from hiding in your pipes and flying up out of the drain. If your pipe has a leak and has no water seal, this can produce a fruit fly problem. Run the water and look below for a leak. If you see one, get it fixed right away. Leaky pipes can cause mold and structural damage to your home. 

You should also call a plumber if your kitchen sink or garbage disposal is draining slowly. This problem not only helps breed fruit flies, but over time the sink drain can fully clog and become unusable. The Midway Services plumbing team has the equipment, experience and expertise to diagnose the problem and fix it promptly. We use a video drain inspector to clearly see what’s happening in the pipes, and a variety of methods to clean them, depending on the type and extent of the blockage. If the problem is your garbage disposal, we can repair or replace it at a price you can afford. We also fix leaky pipes. 

If you want any sort of plumbing service at all, contact the professionals at Midway Services. 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.