Why Are There Fruit Flies in My Kitchen Sink Drain?

Has this ever happened to you? You’re washing a dish in the kitchen sink and watch a tiny creature fly up out of the drain. Is that a gnat? Then you notice 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 you can do 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.” Since they’re lured by moisture and rotting food, they’ll frequently appear in your trash can, your old fruit and the kitchen drain, which is full of moisture and tiny chunks of food. Sometimes you’ll watch them appear up out of the drain. This can be especially bad if you have a partly clogged sink or disposal that clears out slowly. This maintains more moisture and food particles that attracts these insects and enables 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 result in severe cases of food poisoning.

What Can I Do About Them?

Owing to this bacterial risk, keep your surfaces clean at all times. Use a kitchen surface cleaner that destroys bacteria. Don’t reuse sponges that can soak up, retain and transport germs. It’s better to use paper towels and throw them away.

Bug sprays can eliminate the adult fruit flies but won’t kill the eggs. And you probably don’t want to spread insecticide all over your kitchen. Instead, pour boiling water down your drain. Before bed, close up 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—Pour an ounce of wine in the jar. Put a hole in the lid so the fruit flies can get in. You can also use a funnel or paper cone rather than a lid.
• Old fruit—Same as above, but using 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 much harder for flies to break free.
• Yeast—Add 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 as soon you bring it home. Sometimes they can contain fruit fly eggs or larvae.
• Refrigerate whenever you can.
• Try not to keep old produce in your house. 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 prefer to keep windows up, put in some well-fitted screens.

If the above methods haven’t taken care of your fruit fly issue, there may be an issue with your p-trap. That’s the area of your drain pipe bent in a u shape to hold water and prevent foul air from moving up into your home. It also prevents 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 lead to a fruit fly infestation. Run the water and look below for a leak. If you spot one, get it fixed quickly. 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 slower than usual. This problem not only helps breed fruit flies, but over time the sink drain can fully clog and become inoperable. The Stevenson Service Experts plumbing team has the tools, experience and knowledge to determine the problem and solve it promptly. We use a video drain inspector to obviously see what’s happening inside 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 fix leaky pipes.

If you are looking for any sort of plumbing service at all, call the professionals at Stevenson Service Experts. 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.