Size: 1/16 inch
Color: Light gray to tan
Where found: Sewers and drains
Potential treatment: Interior
Drain flies are small, hair-covered flies, light gray to tan in color and 1/16 of an inch long. Their wings are light, translucent and also covered with hair.
These tiny flies can be a nuisance, breeding in sewers and drains, and rapidly reproducing. They gather anywhere there is food debris or decomposing organic materials, laying their eggs virtually anywhere. Their life cycle is typically two to three weeks, but can be more rapid in a favorable environment.
Restaurant kitchens are especially vulnerable to fruit fly infestations. These pests are more active at night and feed on all types of organic matter, including debris that collects within drains, catches and sewers.
Drain flies are fully adaptable to a drain or sewer environment, so it is nearly impossible to drown them. Using insecticides in your drain is generally ineffective and highly discouraged.
While annoying, drain flies do not bite and do not transmit diseases.