Phorid / Sewer Flies
Phorid flies (Phoridae) are about 1/64” to 1/4” long with a characteristic hump-backed appearance. These flies are yellow-brown with a darker brown abdomen, and the first two veins in the wings are heavily sclerotized / dark and easy to see. The adult flies are poor fliers and may run or “scuttle” along a surface before flying. They are also called sewer flies because they are commonly associated with drains to sewers. However, they can infest any drain system that has decaying food or organic materials.
Phorid & Sewer Fly Biology & Habits:
Phorid flies are attracted to decaying organic material (such as pureed garbage under concrete slabs, where pipes servicing a garbage disposal are located), buried dead animals, corpses in mausoleums, accumulations of dead insects in water-logged situations, or in the semi-liquid organic materials found in drains and under pieces of equipment. Adult flies will migrate out of the area in which they are developing, and they are attracted to lights.
Questions To Ask About Phorid & Sewer Flies:
- Where are you seeing them?
- Have you had any plumbing problems, sewage backups, broken pipes (especially under a concrete slab)?
- How has the garbage disposal been working?
- Have there been any accumulations of dead insects or recently buried dead animals.
- Are drains cleaned on a regular basis?
- Is the fly problem associate with a mausoleum?
Phorid & Sewer Fly Inspection Tips:
Pay particular attention around garbage areas, floor drains and dishwashing areas. Check garbage disposal drain pipes for breaks or slow drainage. Look for dirty and chronically wet areas. Check garbage containers for cleanliness. Look for food containers or recycling bins that have been “forgotten” by sanitation or workers.
