If you allow the standing water in your pipes or property to go unchecked, drain flies will rarely go away on their own. Warm homes even allow drain flies to live throughout the winter. Be sure to take preventative measures after flushing out your system to keep drain flies in check.
Boil a medium-size pot of water once or twice per week, and pour down and around the drain. Another easy option uses baking soda: Combine 1/2 cup salt with 1/2 cup baking soda and 1 cup of vinegar, and pour down the drain. Leave overnight, and finish by pouring boiling water down the drain in the morning.
Nine times out of ten, a drain fly problem will go away on its own. Once you get rid of the drain flies that you see, start flushing toilets and running the water in your sinks. This eliminates the standing water in which they dwell.
What Causes Drain Flies? Drain flies thrive in stagnant and standing water. Common sources include slow or clogged drains, rarely used and unused toilets, refrigerator drain pans, and standing water created by leaking pipes. They typically enter buildings through basements, windows, and drains.
The larval stage of drain flies lasts up to 24 days, while the pupal stage lasts between 1 and 2 days at most. The larvae feed on bacteria, fungi, and other microorganisms that develop in the breeding medium in drains, standing water, and even sewage treatment beds.
Most exterminators use chemical methods and habitat modification to kill all eggs, larvae, and adult drain flies (removing food sources, etc.).
One possible sign of an undetected mold problem in your home or office could be the presence of Phorid flies, sewer flies or some other gnats or bugs.
Essential oils are sometimes used to keep flies away from infested sections and also to kill them. Lavender, eucalyptus, peppermint, lemongrass, and citronella are just a few of the scents that insects despise (with lavender probably being the most effective).
So, the starting point would be to check the nearby drain pipes for infestations using the following methods: Duct tape test: Cover all the pipes with sticky tape. As flies try to come out of the drain, they will get stuck on the tape, giving proof of the source of the infestation.
At night, when they are active, they will congregate towards light sources, like lampshades. They will also feed and breed at night, so you'll see them near food sources or breeding areas. You'll most likely see only a few at a time, as you only rarely see drain flies in large numbers at once.
One common remedy for killing drain flies is using household bleach. This is a very useful and cost-effective manner for getting rid of these little pests with an item you already have around the house.
Baking Soda, Boiling Water & Vinegar
The pour half a cup of bicarb soda down the sink as well, followed by a half cup of white vinegar. Let it settle for a few minutes then poor some more boiling water down the drain. Follows these steps every few days until the drain flies have completely disappeared.
For effective drain fly treatment, use three products: Forid Drain Gel Cleaner, Gentrol IGR Aerosol, and Pyrid. Forid is an organic microbial grease degrader that breaks down organic material and waste, which will eliminate their food sources and their breeding grounds.
They do not bite, sting, or spread diseases, but their decaying bodies may cause allergic reactions. They can also spread bacteria from trash, decaying vegetables and fruits. Drain flies breed in areas that are moist and have a lot of organic remains, including: Sinks.
To make an all-natural drain fly trap, fill a bowl with apple cider vinegar and cover it with plastic wrap. Punch small holes in the wrapping. The vinegar's smell will attract the drain flies, and the wrap will trap them inside the bowl.
Besides inadequate control measures, another reason why you have drain flies present again could be because there was a secondary infestation in another site that was not discovered or treated. There may be other bathroom drains, or a floor drain, laundry room drain, or sump pump that are breeding flies.
Are they seasonal? Yes. Cold temperatures significantly slow down the biological processes of drain flies. For example, drain fly eggs will hatch more slowly in cold weather, which suggests that they may stay dormant until warmer weather returns.
These flies will breed in any moist area that they can find. So if you are facing a drain fly infestation that you cannot figure it out, you may want to look deeper for the cause. The problem could be from a leaking pipe or drain under the sink or even a leaking pipe inside of your walls.
These pests are a nuisance because they infest in large numbers. Once inside, drain flies may plug pipes and spread bacteria from the filth they live in, possibly contaminating food in the process. These pests, even though they live in filth, are not known to spread any disease to humans.
Pouring boiling water is quite risky as it might lead to a steam burn or scalding. Another thing to keep in mind is what type of material you are pouring in into. If you have a porcelain sink, it is likely to crack due to the heat. All in all, pouring boiling water down your drain will only cause issues down the road.
Some species hold the wings out to the side, which gives them a moth-like appearance—hence the name "moth fly." They are weak fliers and make irregular, hesitating flights covering only a few feet in short, jerky lines. Eggs are tiny, brown or cream-colored and are laid in irregular masses of 10 to 200.
Preventative Maintenance
Pouring bleach into the drain when the unit is not operating can leave residual bleach, which will damage the drain pan and line. Using vinegar for preventative maintenance throughout the year will keep your drain clean and clear and will not damage your line.
Make a natural cleaning/fly killer mixture.
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.