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 buzz up out of the drain. Was that a gnat? Then you watch more of them buzzing around the kitchen. These annoying little guys are actually fruit flies. And if you’re wondering how they got in there and what you can do 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.” As they’re drawn to moisture and rotten food, they’ll head for your trash can, your old fruit and the kitchen drain, which is filled with moisture and tiny bits of food. Occasionally you’ll see them come up out of the drain. This can be particularly frustrating if you have a somewhat 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 lead to severe cases of food poisoning. 

What Can I Do About Them? 

Due to this bacterial exposure, keep high-traffic 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 better to use paper towels and throw them out. 

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

Here are other traps you can also attempt, all utilizing a jar: 

• Wine—Add an ounce of wine inside the jar. Put a hole in the lid so the fruit flies can get in. You can also use a funnel or paper cone in the place of a lid. 

• Rotten fruit—Same as above, but use 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 harder for flies to escape. 
• Yeast—Put in two or three ounces of water, one packet of activated dry yeast and a teaspoon of sugar. 

To minimize bringing in fruit flies: 

• Clean your produce as soon as you take it home. Sometimes they can contain fruit fly eggs or larvae. 
• Refrigerate whenever you can. 
• Avoid keeping spoiled 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 want to keep windows raised, put in some well-fitted screens. 

If the above methods haven’t taken care of your fruit fly problem, there may be something wrong with your p-trap. That’s the area of your drain pipe bent in a u shape to hold water and keep foul air from wafting up into your home. It also prevents flies from hiding in your pipes and flying up from the drain. If your pipe has a leak and lacks a water seal, this can create a fruit fly problem. Run the water and search below for a leak. If you spot 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 slower than usual. This problem not only helps encourage fruit flies, but over time the sink drain can fully clog and become unusable. The Service Experts Heating, Air Conditioning & Plumbing plumbing team has the tools, experience and knowledge to identify the problem and solve it right away. We use a video drain inspector to plainly see what’s going on in the pipes, and a number of methods to clean them, depending on the type and severity of the blockage. If the problem is your garbage disposal, we can repair or replace it at a price you can afford. We also handle 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 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.