Drain flies, or moth flies, are a common household nuisance that can quickly take over your kitchen, bathroom, and laundry room if left unchecked. These tiny, fuzzy flies breed in the organic gunk that builds up in the home’s drains, pipes, and other damp areas. While drain flies don’t pose any serious health risks, their presence can be unsanitary and unpleasant.

Fortunately, you can use several safe and effective methods to how to get rid of drain flies for good. In this guide, we’ll cover everything you need to know about identifying, treating, and preventing drain fly infestations. By the end, you’ll have the knowledge and tools to banish these pesky pests from your home.

What Are Drain Flies?

Drain flies (Psychoda spp.) are very small flies that measure less than a quarter-inch (3-6 millimeters) in length. They have a distinctive fuzzy, moth-like appearance with gray to black coloring and hairy bodies and wings, says Jim Fredericks, a board-certified entomologist at the National Pest Management Association (NPMA).

Drain flies are typically found in damp, humid areas of the home, such as sinks, showers, bathtubs, floor drains, and laundry rooms. They breed in the organic debris and slime that builds up in slow or clogged pipes, feeding on the microorganisms that thrive in this environment, says Timothy Wong, technical director at MMPC.

Drain flies live eight to 24 days but can lay and hatch up to 300 eggs in just 48 hours. Because of this, it’s important to get ahead of the problem before it can spread through your pipes.

Drain Flies vs. Fruit Flies

It’s easy to confuse drain flies with their cousins, the fruit flies. However, there are a few key differences between the two:

• Habitat: Drain flies congregate around drains, leaky pipes, and sewers, while fruit flies are attracted to decaying or fermenting fruits and vegetables.
• Appearance: Drain flies have a distinct fuzzy, moth-like look, while fruit flies do not.
• Flying Behavior: Drain flies are poor flyers and tend to crawl and hop rather than take flight. Fruit flies, on the other hand, are excellent flyers.

You can easily tell the flies apart by paying attention to where you see them and their physical characteristics.

What Causes Drain Flies?

Drain flies thrive in standing water and stagnant, damp environments. The most common causes of drain fly infestations include:

• Slow or Clogged Drains: Organic debris like hair, food particles, and soap scum can build up in drains, creating the perfect breeding ground for drain flies.
• Rarely Used or Unused Toilets: Standing water in unused or infrequently flushed toilets provides an ideal habitat for drain flies to lay their eggs.
• Refrigerator Drain Pans: The moisture and organic matter that collects in these pans can attract and support drain fly populations.
• Leaking Pipes: Any source of standing water, including leaks from pipes, sinks, or appliances, can cause a drain fly infestation.

Drain flies typically enter buildings through basements, windows, and drains, so homes with poor sealing or ventilation are more susceptible to these pests.

How To Tell if You Have Drain Flies

During the day, you may notice drain flies resting on walls or other surfaces, as they are not strong flyers. At night, when they are most active, you’ll likely see them congregating around light sources or near their breeding and feeding areas.

Look for small, fuzzy flies hovering around your home’s drains, sinks, or other damp spots. You may also spot them crawling or hopping along surfaces. If you notice these telltale signs, you likely have a drain fly problem that needs to be addressed.

How to Kill Drain Flies Safe and Natural

There are several safe and natural ways to get rid of drain flies in your home. Try these effective methods:

Boiling Water

Bring a pot of water to a rolling boil and pour it down the affected drain 1-2 times per day for a week. The heat will kill adult flies, larvae, and eggs in the drain.

Baking Soda and Vinegar

Mix ½ cups of salt, ½ cups of baking soda, and 1 cup of vinegar and pour the solution down the drain. Let it sit overnight, then follow up with a pot of boiling water in the morning. The chemical reaction will help break down the organic matter that drain flies feed on.

Sugar, Water, and Vinegar Trap

Make a simple fly trap by mixing 1 cup of warm water, 1 tablespoon of sugar, and 1 tablespoon of vinegar in a bowl. Cover the bowl tightly with plastic wrap and poke a few small holes in the top. The flies will be attracted to the sweet-sour mixture and become trapped inside.

Apple Cider Vinegar Trap

Pour ¼ cup of apple cider vinegar into a glass and cover it tightly with plastic wrap. Poke several holes in the wrap with a fork. Place the trap near the affected drain, and the flies will be lured in and drown in the vinegar.

Snake Out the Debris

Use a plumbing snake or other drain clog remover tool to physically remove the built-up gunk and debris inside the pipe. This will eliminate the food source and breeding ground for drain flies.

Enzyme Cleaners

Apply an enzyme or microbial-based drain cleaner to the affected area. These products contain beneficial bacteria and enzymes that break down the organic matter and biofilm that drain flies feed on, removing their food source.

How Do I Prevent Drain Flies From Returning?

The best way to keep drain flies from returning (or getting them in the first place) is through regular maintenance and vigilant sanitation practices. Here are some tips:

• Fix Plumbing Leaks: Address any leaks from pipes, sinks, or appliances to eliminate standing water sources.
• Keep Drains Clean: Regularly use enzymatic or microbial drain cleaners to remove built-up debris and biofilm.
• Cover Drains: When not in use, cover the sink, shower, and other drains to prevent flies from getting in.
• Dispose of Trash Daily: Remove any garbage or food waste that could attract and feed drain flies.
• Seal Cracks and Crevices: Ensure windows, doors, and other entry points are properly sealed to keep flies out.
• Discard Decaying Food: Promptly throw away any spoiled or decaying fruits, vegetables, or other food that could draw in drain flies.

You can keep drain fly infestations at bay by staying on top of drain maintenance and eliminating potential breeding sites.

When to Call Professionals

If you’ve tried the DIY methods above and are still struggling with a persistent drain fly problem, it may be time to call the professionals. TaskPro offers emergency plumbing and specialized drainage services to get to the root of the problem and ensure a long-term solution.

Call us for regular drain cleaning and maintenance to ensure your pipes stay clear and free of potential drain fly breeding grounds.

FAQs

How long does it take for drain flies to go away?

With consistent treatment and preventative measures, you can typically get rid of a drain fly infestation within 1-2 weeks. However, suppose the problem is severe, or the source needs to be properly addressed. In that case, it may take longer to eliminate the flies fully.

Are drain flies harmful?

Fortunately, drain flies are not known to transmit any diseases or pose serious health risks to humans. However, their presence can be unsanitary and unpleasant, as they breed in dirty, damp environments and can contaminate food preparation areas.

Do drain flies mean I have a leak?

Not necessarily. Drain flies are attracted to any source of standing water, including clogged drains, unused toilets, and leaking pipes. While a drain fly infestation may indicate a leak somewhere in your plumbing system, it’s not a guarantee. Inspect your home for other signs of water issues to determine the root cause.