Drain Fly

Natural Habitat

Humid areas with decomposing organic matter, such as bathroom drains, sewers, and septic tanks.

Diet & Feeding

Larvae feed on the gelatinous film of bacteria and organic sludge in drains; adults primarily consume liquid carbohydrates or do not feed at all.

Behavior Patterns

They are weak fliers and often seen crawling on walls near drains. They are most active at night and have a life cycle that takes 7 to 28 days.

Risks & Benefits

Generally harmless and do not bite or transmit diseases. However, they can be a nuisance and may potentially spread bacteria from contaminated drains to food surfaces.

Identified on: 5/19/2026