How to Kill Sewer Flies

Sewer flies are attracted to bacteria in piping.

Sewer flies are a large problem for many homeowners. A female sewer fly can lay up to 200 eggs at a time that hatch within 48 hours. This insect is found in moist and damp areas like sub pumps, bathtubs, sinks and around wet piping, where they feed off bacteria. There are four stages in the life of a sewer fly including the egg, larvae, pupae and adult stage. The first three stages take two-to-three weeks to complete and the adult stage lasts approximately three weeks. To prevent this insect from breeding, it is important to kill it. To eliminate the infestation, the larvae must also be killed.

Things You'll Need

• Wire brush pipe cleaner
• Antibacterial drain gel
• Aerosol bug killer
• Pan
• Wrench

Instructions

1. Take a wire brush and clean out the interior of the pipes where the sewer flies are infesting. Remove as much debris in the pipes as possible. If you cannot reach all the areas of the pipes, use a wrench to take them apart. Be sure to seal the pipes tightly when reassembling them.

2. Boil water in a pan and pour it down the drain so it goes throughout the inside of the pipes to kill the bacteria. Do this several times to flush out any loose debris leftover from the wire brush.

3. Pour the antibacterial drain gel into the piping and allow it to sit as directed on the container. This will kill any leftover bacteria on the inside of the pipes that the boiling water didn't and will prevent any reinfestation from occurring after the cleaning.

4. Spray the exterior of the pipes wherever you can reach with a bug repellant to eliminate sewer flies outside of the piping. Spray as directed on the can and repeat every few days until the sewer flies are completely gone.

References

• New York City Department of Health and Mental Hygiene: Environmental Health Services; Sewer Flies
• Iowa State University of Science and Technology: Iowa Insect Information Notes: Moth Flies; 2005