The goal is to eliminate their breeding site. The most effective method for doing this is to call a plumber and have them mechanically clean the pipes of the slime and organic material that tends to collect in the pipes and drains.
For large infestations, long-term control and the prevention of future infestations, there's really nothing as effective as investing in a professional drain cleaning service. This preventative measure will get your pipes cleaner than you ever could on your own.
Clean suspected drains with a commercial drain cleaner, and scrub the drain pipe vigorously with a long-handled brush. After their breeding sites have been eliminated, the reproductive cycle is disturbed. If you experience difficulty ridding your home of adult sewer flies, contact your local pest control professional.
Your local Orkin Pro is trained to help manage drain flies and similar pests.
The average cost for drain fly pest control services is $200. However, the price can range from as low as $100 to $500 in some cases, depending on the severity of the infestation and the size of the area that needs to be treated.
Mix together 1/2 cup of salt, 1/2 cup baking soda and 1 cup of vinegar. Pour the mixture down the drain. Let sit overnight, then flush the drain with hot water in the morning. This should kill all flies and the organic material they've been feeding on.
Learn the Pest Biology
Knowing the life cycle helps you fight fly infestations. Life Cycle: Adult females lay 30–100 eggs in sludge around sewage and drainage areas. Eggs hatch in 32–48 hours, larval stage lasts 8–24 days, pupal stage 20–40 hours. Adults live about two weeks.
Look for potential breeding spots near drains or other sources of standing water. If you're unsure which drain is the source, line a clear plastic cup with a very light coating of vegetable oil or petroleum jelly and invert over the suspected drain for several days.
An ongoing or recurring infestation, despite careful sanitation of all drains, can indicate a broken pipe or leak under a slab or in a crawlspace beneath the home.
Bleach will absolutely kill drain flies. However, using bleach comes with certain risks. It's better to try other methods first and use bleach as a last resort.
If your drain fly issue persists, consider using commercial drain cleaners such as Drano. These solutions are formulated to clear out the drains and pipes effectively, removing any debris that might serve as a breeding spot for drain flies. Using these products can aid in preventing new eggs from hatching.
Drain flies are most often the result of a clog in a drain or sewer line, it doesn't matter if it's buildup, a soft clog or a hard clog – it just needs to limit the flow of wastewater, causing it to become stagnant and a breeding ground for bacteria. That's not the only time you might find these pests, however.
Pour Vinegar and Baking Soda Down the Drain
This will clear out the buildup in your drains, eliminating drain fly habitats.
Peppermint, eucalyptus, and tea tree oils are especially beneficial. Pour a few drops of the chosen oil with water down the toilet. The oils' pungent aroma repels drain flies and disturbs their breeding cycle. To keep the solution effective, reapply it every few days.
Clean Your Drain
Boiling Water: Pour boiling water down your drains to wash away gnats and their eggs. Baking Soda Solutions: Use a mixture of salt, baking soda, and white vinegar to foam away bacteria in your pipes. Chemical Cleaners: For intense infestations, consider using a chemical cleaner like Drano.
Drain flies, also known as sewer gnats, feed and lay eggs on decaying organic matter. So, an overfull septic tank provides a breeding ground for these little pests. They are only about ⅛ of an inch big, but you will notice them hovering around bathtubs, sinks, and showers.
In those instances, their breeding area may be a clogged gutter or other source of standing water outside. What if you're still unable to get rid of drain flies? If you have killed many sets of drain flies over the course of more than 2 weeks, your house many have a well-developed breeding site.
Drain flies are both a pest problem and plumbing problem because they infest your bathroom and/or plumbing fixtures. Even though flies can live pretty much anywhere, you can prevent them from living near you.
Drain Flies are seasonal and you'll notice them in the spring... or not!
Behavior and Habitat of Drain Flies
Their larvae feed on the organic matter present in these locations, including decaying vegetation and trapped debris. Drain flies are primarily nocturnal and are most active during the evening.
In homes, the adult flies are most likely found on the walls of the bathrooms, kitchens, basements and other locations where sewer drains and plumbing fixtures are located. The flies are poor fliers and usually are found close to the drain or area of origin.
Most of the time, flies live in organic materials. Check for flies in places like the soil around houseplants or in your trash. They're also commonly found in bathrooms or in areas around or inside drains. You should also check for gaps along your house's foundation, windows, and doors.
Drain flies feed on filth and scum that can build up in areas such as drains, drain openings, sewers, septic tanks, and kitchen sinks. A great way to identify which drain-source the flies are coming from is to put clear tape over the drain so that they will fly into it and get stuck.
The simple answer is yes but with a caveat. While bleach can kill drain flies and their larvae on contact, it's not the most effective method for long-term control. Bleach's caustic nature allows it to clean the drain pipes and kill some of the larvae.