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(Off Topic) Drain Flies (Brad White)

mtfallsmikey Member Posts: 765
Figured out. If the problem is as persistent as you say it is, get a plumber to water jet the lines, if possible. Used to see this problem a lot in grocery store deli drains, and around grease traps.


  • Brad White
    Brad White Member Posts: 2,393
    What a terrible title and association

    I have a question for the plumbers out there (OK, my Susan does- she knows where to go):

    Starting last fall and again this past summer, we had what seemed like fruit flies, small swarms, near the drains. We think they came in on bananas. They do hang around drains both in the kitchen and more annoyingly, the upstairs bath lavatories.

    We went to an on-line DIY pest control company and got them under control each time. Now, with the first cold weather, they are back, much as they were almost exactly a year ago. Bleach does not work, just as they said.

    The housekeeping standards are fine, really. Not Martha Stewart but not bad. Plenty of hot water (ya think?) and the drains seem to run clear.

    Last fall was the first time these were ever noticed and this would be the third wave.

    What have you plumbers seen that attracts them to drains, what might cause or promote them in your experience?

    As for plumbing changes, the only thing coincident to this is the use of an old laundry indirect connection for the Vitodens after the neutralizer. It is trapped and vented per code. No flies evident down there.

    Sorry if off-topic but after treating the symptoms for two going on three times, I am suspecting another cause.

    Thanks in advance,

    "If you do not know the answer, say, "I do not know the answer", and you will be correct!"

    -Ernie White, my Dad
  • Brad,

    I had a similar prob, they seem to like basins because of the gunk in overflow passage(precast). I jammed a rag in the P.O.plug(below the overflow passage), and added bleach to the standing water allowing it to flow down this way.
    Cured my problem!

  • Uni R_3
    Uni R_3 Member Posts: 299
    Having the same issue...

    It's the fruit and vegetables that taste better unrefrigerated, especially to those little pests!

    Here's a good link on solutions:
  • Rich Kontny_3
    Rich Kontny_3 Member Posts: 562
    Sewer Flies

    Those little buggers (no pun intended) can be a nuisance if you have to work on the sewer side of a trap.I believe they thrive in the wet dark environment of sewers and have trouble once they see the light of day.There are chlorination and other kill solutions yet in this day and age of environmentally friendly products I would check around to see if "the cure is worst than the ailment"

    Rich Kontny

    Make Peace our Passion while supporting our Troops!
  • Ed Norton,

    how did we wind-up in the sewer?

  • John_173
    John_173 Member Posts: 63
    sewer flies

    Or sir flies, down here in the Southland. Must be some lady flies, too, since the @$%^ things are multiplying.

    They love the slime that clings to the waste pipe. Hot water, bleach, etc. won't do it without temporarily blocking the waste downstream. A bottle brush scrubs out the slime so the little bug(ger)s have no sweet slimey home.
  • Bruce M
    Bruce M Member Posts: 166

    Reminds me of the time my daughter decided that she did not want to share the bananas with her big brother.

    She hid them in her room.

    First.....the flies

    Then....the smell.

    We used fly paper.

    Oh....not for the flies......we wrapped our daughter in it and hung her from the ceiling.

    Make sure Susan isn't hoarding food some where.

    Best of luck!

    Mark H
  • Plumdog_2
    Plumdog_2 Member Posts: 873
    My theory

    is; they come in the potting soil. We have a very tidy friend that watches everything like a hawk, and she thinks so too.
  • Jim Franklin
    Jim Franklin Member Posts: 170

    They seem much more prevalent now than ever before. Every restaurant has them and some friends houses too.

    I get rid of them by building a trap. Apple cider vinegar and water in a clear plastic cup, with a touch of dish soap to kill the surface tension. Put a paper cone or funnel in the top. They get in but won't get out. It takes a while for them to commit to entring the cup, i.e. it's not entertaining to watch, but they do eventually all go away.

  • we have the problem up here too

    Brad. Someone told me to pour a little bleach down EACH DRAIN, I forgot one and had to do it again, add bleach every night before you go to bed for about a week. My flies are gone. She said they lay their eggs at the water line in the drain. Good luck Brad, Bob Gagnon

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  • Stuart Rogers
    Stuart Rogers Member Posts: 44
    fly traps

    Good solution. There's a commercial version available, and it works very well:
  • bert
    bert Member Posts: 50
    not for everyone

    From my old farm days, we had what we generically refered to as milk-house spray. It was actually FDA approved to kill the flies in milking parlors and milk rooms, even though it probably has some nasty chemicals in it.
    After the revolving door days of summer, and the kids now remember to close the doors again, I pick two days in a row with everyone gone and do a quick walk thru the house with the spray. Not only gets rid of the flies, but moths, fruit flies, and even some spiders.
  • Dr. Z
    Dr. Z Member Posts: 6
    Drain Flies

    These guys are well known to the water-treatment guys (okay, sewage treatment guys) and are referred to as filter flies, since they tend to swarm around the mucky filters in the cleanup systems.

    A good summary at the following web site:
  • Mike T., Swampeast MO
    Mike T., Swampeast MO Member Posts: 6,928

    Have the same problem on numerous occasions and in places where there are NO bananas. Pro exterminators (at least that's the only place I've seen) have a sort of fogger that gives a small burst at timed intervals until the can is empty. Food safe as it's been used in my bar.

    Have never had them in a kitchen sink, but have certainly had them in lavs. Web advice is sort of right that bleach is ineffective. A quick pour down the drain does nothing--it [seems] to take a toxic soak...

    Suspect they're mainly nesting in the overflow of lavs and in anyplace (including venting) that's not normally in contact with water in other sinks.

    Not a month ago, I did this to exterminate (at least this batch) a colony in a lav by:

    1) Spray Dow "Scrubbing Bubbles" liberally at lav and tub and let sit.

    2) Run only hot water down lav and tub drains for a few minutes.

    3) Close drains and add about a half-gallon of bleach to each. Fill with hot water to overflow and add a few more ounces of bleach to each.

    4) Leave room and shut the door due to fumes and heat.

    5) Return after a while. Run hot & cold full blast for a few minutes without opening drains.

    6) Clean, clean, clean.

    Finally: Regret the energy you used for all that hot water...

This discussion has been closed.