Drain Fly Larva

Natural Habitat

Stagnant water, gelatinous slime or 'biofilm' within drains, sewage pipes, and moist decaying organic matter.

Diet & Feeding

Feed on decaying organic materials, fungi, and bacteria found in drain biofilms.

Behavior Patterns

Larvae are aquatic or semi-aquatic, living within the slime layer of pipes; they pupate near the surface and emerge as fuzzy, moth-like adult flies.

Risks & Benefits

Generally harmless to humans but can be a nuisance; in heavy infestations, they may carry bacteria from sewers into living spaces, though they do not bite.

Identified on: 2/19/2026