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Drain Flies

Drain flies are small flies, about 1/8th inch. They are usually black, but may be brown. The key identifying trait for this fly is the unique pattern of veins in its wings.

Drain Flies are also called moth flies, sewer flies or filter flies. Their bodies and wings are covered with numerous hairs. If crushed they leave a powdery smudge. The flies are commonly found around drains, but they should not be confused with the Fruit fly, Phorid fly, or Sphaerocierid fly which also infest drains.




The best control for these flies is to remove the breeding site, which is the organic material that collected in the drain. If these flies are present in the house there is almost certainly a slow or clogged drain. Find the drain and physically clean it out. All the liquid drain cleaner in the world will not solve the problem, you’ve got to physically remove the material causing the clog. Once the material is removed (along with the larvae) the problem is solved, except for the adult flies. They will live about 20 days, but since they will have no place to lay eggs, the problem will disappear when they die