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Drain (Moth) Fly
Adult drain fly (Joseph Berger, Bugwood.org)
Adult drain fly (Sanjay Acharya, Wikimedia Commons)
- small: about 1/8 inch long
- very hairy
- wings covered in fine hairs; moth-like
- develop in the scum lining drains and sewer lines or decaying organic material
- larvae hide behind scum making attempted treatments with boiling water, pesticides or other chemicals ineffective
- can breed around broken pipes/drains beneath slabs or in crawlspaces, and enter buildings through floor cracks, etc.
- drain scum
- decaying organic matter
- can spread disease through contact
- bodies of dead flies may disintegrate to form allergens
- Locate the breeding site and remove.
- Remove larval habitat by using a hard bristle brush to remove the scum film from inside the drain.
- Use an enzyme drain cleanser to maintain drains free of organic film.
- If flies are coming from voids, crawl spaces or slabs, fix the moisture issue causing the problem and seal.
IPM for Flies: Integrated Pest Management in Sensitive Environments (University of Nebraska-Lincoln Extension)