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 notice a small creature shoot up out of the drain. Was that a gnat? Then you see more of them buzzing around the 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 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.” As they’re attracted to moisture and rotting food, they’ll frequently appear in your trash can, your rotten fruit and the kitchen drain, which is filled with moisture and little pieces of food. Sometimes you’ll watch them fly up out of the drain. This can be particularly bad if you have a partially clogged sink or disposal that drains slowly. This maintains 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 lead to acute cases of food poisoning. 

What Can I Do About Them? 

Due to 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 out. 

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

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

• Wine—Pour an ounce of wine in the jar. Put a hole in the lid so the fruit flies can access the wine. You can also use a funnel or paper cone rather than a lid. 

• Spoiled fruit—Same as above, but with rotten fruit instead 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 as well, 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 as well as a teaspoon of sugar. 

To prevent bringing in fruit flies: 

• Rinse your produce immediately after bringing it home. Occasionally they can possess fruit fly eggs or larvae. 
• Refrigerate whenever you can. 
• Try not to keep spoiled 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 like to keep windows up, make sure they have well-fitted screens. 

If the above methods haven’t resolved your fruit fly infestation, there might be a problem with your p-trap. That’s the part of your drain pipe bent in a u shape to trap water and stop foul air from wafting up into your home. It also stops flies from surviving in your pipes and flying up out of the drain. If your pipe has a leak and is missing a water seal, this can create a fruit fly problem. Run the water and check below for a leak. If you find 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 more slowly than usual. This problem not only helps encourage fruit flies, but over time the sink drain can entirely clog and become inoperable. The Service Experts Heating, Air Conditioning & Plumbing plumbing team has the tools, experience and knowledge to identify the problem and resolve it right away. We use a video drain inspector to clearly see what’s occurring within the pipes, and multiple methods to clean them, depending on the type and extent of the blockage. If the problem is a 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, 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 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.