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 small creature fly up out of the drain. Is that a gnat? Then you watch 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 can be done about them, you’re in the right place. 

Why Are They Here? 

Fruit flies live 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 lured by moisture and decomposing food, they’ll often end up in your trash can, your rotten fruit and the kitchen drain, which is packed with moisture and small chunks of food. Occasionally you’ll watch them come up out of the drain. This can be especially bad if you have a somewhat clogged sink or disposal that empties slowly. This maintains more moisture and food particles that draws these insects and allows them to thrive and reproduce. 

How Bad Are They? 

When fruit flies transfer from a dirty surface to a clean one, they lug germs with them. This can include listeria, salmonella and even E. coli. All of these bacteria can cause severe cases of food poisoning. 

What Can I Do About Them? 

Due to this bacterial risk, keep high-traffic surfaces clean at all times. Use a kitchen surface cleaner that kills bacteria. Don’t reuse sponges that can absorb, retain and transport germs. It’s better to use paper towels and throw them out. 

Bug sprays can eliminate the adult fruit flies but won’t get rid of the eggs. And you probably don’t want to spray insecticide all over your kitchen. Instead, run boiling water in your drain. Before bed, block off your drains with clear packing tape. In the morning, you can see some fruit flies stuck to it. 

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

• Wine—Put an ounce of wine into 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. 

• Old fruit—Same as above, but with rotten fruit instead 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 added, which makes it much harder for flies to escape. 
• Yeast—Pour in two or three ounces of water, one packet of activated dry yeast as well as a teaspoon of sugar. 

To minimize bringing in fruit flies: 

• Wash your produce as soon you bring it home. In some cases they can possess fruit fly eggs or larvae. 
• Refrigerate as soon as you can. 
• Don’t keep overripe 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, make sure they have well-fitted screens. 

If the above methods haven’t eliminated your fruit fly issue, there may be a problem with your p-trap. That’s the section of your drain pipe bent in a u shape to trap water and stop foul air from wafting up into your home. It also prevents flies from living 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 look below for a leak. If you notice one, get it fixed promptly. Leaky pipes can cause mold and structural damage to 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 attract 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 equipment, experience and knowledge to determine the problem and solve it quickly. We utilize a video drain inspector to plainly see what’s happening within the pipes, and a number 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 resolve leaky pipes. 

If you want 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 happy. 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.