Pest Guide for Drain Flies
Drain flies, also known as sink flies or sewer gnats, are small flies that are commonly found in places like the bathroom or kitchen. There are more than 4,500 known species of drain flies worldwide and once they inhabit plumbing or sewage systems, they can be difficult to get rid of.
Appearance
Drain flies are among some of the smallest species of flies. They measure anywhere from 1.5 millimeters to 5 millimeters and have light grey or tan-colored bodies with even lighter wings. Both their bodies and their wings are covered in long hairs, which gives them a “fuzzy” appearance.
Habits
Drain flies are typically nocturnal, but they can often times be found around light sources. This means that while they’re mostly active at night, you may see them near windows, lights, or bright colors during the day. These flies are common in moist areas and can be found near house or sewage drains, decaying logs, compost piles, and more. (If you do find drain flies in your home, you likely have a slow or clogged drain.) While they feed on organic matter and sewage, they do not transmit human diseases like the house fly.
Infestations
Because these flies are so small, they can easily pass through screens, small cracks, and openings, making it easy for them to enter your home. Drain flies and their eggs are resistant to many different chemicals and toxins, making getting rid of them difficult to do on your own. The most common sign of a drain fly infestation is the fly itself, which may be seen resting on the walls or near the drain. If you find you have a drain fly problem, let our experts take care of it.