Drain Flies: How to Exterminate These Pests from Your Pipes

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Hi there, I'm Margery. Welcome to my site about pest control. Cockroaches, house centipedes and ants all make home life a true disaster upon entering the living space. These creatures can crawl through the food and appear above people trying to sleep in their beds. Many people dislike even thinking about the possibility of pests crawling through the walls or under the floors. I will use this site to talk about how professional pest exterminators control the population of these creatures. I hope you can use the information on my site to keep your home pest-free as well. Thanks for visiting.

Drain Flies: How to Exterminate These Pests from Your Pipes

15 March 2016
, Articles

Drain flies, also known as sewage flies or moth flies, are tiny flying insects that swarm out of drains, often as a result of some sort of plumbing or drainage issue. If there is decomposing material lining the interior walls of your plumbing pipes, this creates the perfect environment for drain flies to feed and breed inside the pipes. The following tips can help you eliminate these unwelcome guests from your home.

Find the Source of the Drain Flies

Before you can get rid of these pests, you need to figure out where they're coming from. Adult drain flies may be small (about one-third the size of a common housefly), but these nasty little buggers can become a real nuisance when left untreated because they continue to breed. If you have a backed-up or slow-moving drain in your home, this is likely the source of your problem.

These steps can help you easily figure out which drain is the source of your drain fly problem:

  1. Stick two pieces of masking tape over each bathtub and sink drain opening in your home. 
  2. Form an "X" with the masking tape pieces to avoid obstructing the airflow in the drain. Leave the tape on each drain overnight since drain flies are most active at night.
  3. In the morning, check the sticky side of the tape for dead drain flies. This way, you can easily determine which drain is the source of your problem.

Eliminate the Breeding Ground of Drain Flies

Once you've identified the source of drain flies, you must eliminate this breeding ground from your plumbing pipes. Drain flies complete their life cycle within the decomposing material inside your pipes, so this slimy gunk must be completely removed to truly solve the problem. Here's what you need to do:

  1. Insert a pipe snake or brush down the drain and gently scrub away any material lining the interior of the drain pipe. Intermittently run warm water down the drain to help rinse away the loosened gunk. You may also use a plunger, if necessary, to pull out stubborn material from the drain.
  2. Once the pipe has been cleared, open up the drain's U-trap to remove any leftover material that has collected inside.
  3. Pour an enzymatic drain cleaning gel down the drain (according to the manufacturer's instructions on the label) to coat the interior walls of the pipe and kill any hidden gunk your pipe snake might have missed.
  4. Let the gel sit in the drain pipe for the amount of time recommended by the manufacturer's label.
  5. Finally, turn on the faucet to flush the gel from your drain pipe.

Keep in mind that chemical drain cleaners can be hard on your plumbing system, so they should always be used sparingly.

Get Rid of Adult Drain Flies

Once you've cleaned out the nasty gunk that contains drain fly eggs and larvae, you've eliminated the breeding ground from your drain pipe. But what about the adult drain flies still swarming around your kitchen or bathroom?

Over time, the adults will have no choice but to disappear because there is nowhere left to deposit their eggs, meaning new flies won't grow. The life cycle of a drain fly typically lasts anywhere from 10 to 15 days, depending on the environment, so any lingering adults should be gone within that period of time.

After completing the steps listed above, if drain flies continue to be a problem in your home, you probably haven't completely removed the source of the problem. If drain flies are still swarming around your kitchen or bathroom a couple weeks after treatment, they must be continuing to breed somewhere within your pipes. In this case, your best bet is to call in a pest control company or plumber because the problem may lie deeper within your plumbing system. Speak with a representative from a service like Cavanaugh's Professional Termite & Pest Services to get started.