Drain flies are also called moth flies and they are one of the many insects that pest control companies frequently deal with.

Biology of Drain Flies
Drain flies are small and have dark wings. These are a type of gnat that has wings covered in scales. This means that if you mash or swat them, they will disappear with a cloud of dust accompanying them from the scales. The drain flies will typically spend time sitting on your ceilings or walls and then make flights that are essentially short hops when disturbed. Drain flies are most active in the evening, typically resting during the day. Drain flies are typically attracted to standing water, making them more likely to be present in a home following extended travel. As with most other insects, drain flies go through several stages of development, including larva, pupa, and adult.

The life cycle of drain flies lasts between 10 and 15 days when the temperatures are around 70 degrees Fahrenheit. Drain flies lay their eggs on organic matter that is on a gelatinous film. Eggs are laid in groups of between 30 and 100 and then hatch within 48 hours. The larvae will develop on either thin surface films or on water, as will the pupae. The larvae will eat sediment, microscopic animals and plants, and decaying vegetation. The larval stage for drain flies typically lasts between 9 and 15 days. From there, the pupation stage lasts just 20 to 40 hours. When the adult flies emerge, they are sexually mature. Drain flies will usually copulate within just hours of adult life.



Why Drain Flies Are Considered Pests
In most cases, if you only see a few drain flies, it can be taken care of easily without much challenge. Even in small numbers, however, drain flies can be pests due to their ability to infest your home and get in the way of an otherwise clean space, like a kitchen. There can also be concerns about sanitation in a food-preparation area. There is also the general concern associated with having any insects in your home. The number of drain flies may also cause problems for those who are squeamish, particularly when in the kitchen or bathroom. You may also spot the wriggling larvae in water, something no squeamish person will appreciate.

In situations with more than just a handful of drain flies, then they can become a constant nuisance, turning them into true pests. Their status as a pest is only solidified by the fact that larger numbers are incredibly challenging to eliminate. The good news is that drain flies do not bite, nor do they transmit any disease to humans. It is possible, however, for the fly larvae to lead to a parasitic infection known as myiasis where the larvae grow in human tissue. Those who are susceptible to bronchial asthma may also find their condition worsening if drain flies are present.

Methods for Controlling Drain Flies
Controlling drain flies will always begin with an inspection to get an idea of the numbers and the breeding sites. Drains will typically be the focus of this inspection since the flies live off of the water and slime in the drains. You can confirm that you do have drain flies by placing tape on the drain but including several holes to allow for air flow. If you have drain flies, some will get stuck on the tape. If an expert feels that you have drain flies breeding under a slab floor thanks to a broken pipe, it becomes more complicated. You can check if it is a breeding site using tape like you would with a drain. If this is likely the breeding site, then a professional will need to break a hole in the slab to check for flies and a broken pipe. They will then need to dig into the soil underneath the slab for inspection.

The inspection for drain flies and their breeding locations will also include sewers and sump pits. Drains to be checked inside the home include the shower drain, other bathroom drains, and kitchen equipment. Although insecticides are useful for controlling drain flies, you should never use them by pouring them down sinks. This is dangerous due to the chemicals. Instead, opt for contact aerosols, which are non-residual insecticides that will kill the adult flies. You can also get insect light traps, although these are more likely to catch other flies more often than drain flies.

DIY Tips for How to Get Rid of Drain Flies
When dealing with just a few drain flies, you can typically just kill each adult individually by swatting it or spraying it with an insecticide for flying insects. This method, however, is not effective or practical when dealing with larger numbers of drain flies. You can both identify the breeding sites of drainage flies and catch some of them with a simple trap. Just got a clear plastic cup and lightly coat it with petroleum jelly or vegetable oil. Place this over the drain and you will catch flies and be able to monitor their numbers and locations.

Since drain flies are attracted to wet areas for breeding sites, your best method of control will be to eliminate these breeding sites. Start by cleaning pipes as well as any traps thoroughly to get rid of the slime. You can see short-term results by dumping hot water down the drain. Unfortunately, drain fly larvae can trap air bubbles and stay underwater for over a day, making them hard to drown. To fully eliminate drain flies and prevent them, you will need to thoroughly clean the drain and all other areas, such as toilets and sinks. You should get rid of any produce that is rotting immediately. Try keeping your garbage as far from the home as you can. The best DIY method for controlling drain flies will be to reduce moisture, which can include fixing leaks, taking care of condensation problems, and installing fans. Unless you find and eliminate the breeding site, the drain fly infestation will continue.

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