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Hello and thanks for any help.

My home was built in 71, Florida block home. Purchased about 10 years ago.

For the past 6 months I have been having a drain fly issue in one bathroom bathtub, looked on-line, kept reading that the foaming drain killer would get rid of them, tried this, at first I believe it helped, they went away for a few days but came back.

Ive prob. dumped a dozen down the drain now, I assumed that maybe the winter cold might get rid of them, didnt have much of a winter here this year, they did seem to disappear but with warmer weather they are now back.

Rented a drill/wand cleaner deal, ( this A.M ) ran it down the line, never had much of a draining issue, dont believe there is or was any major clog. Dont think this helped.

Took the cover off the septic tank which is maybe 15-20 feet away from this bathtub drain just outside the house, thousands of drain flies, they are everywhere in the tank, I believe they are just coming back up the pipe into the house and this is the closest exiting drain for them.

What can I do to get rid of these things?
 
Is there a P trap under the tub somewhere hidden within the concrete, stupid question maybe but I do not know how these homes are/were built and I am under the assumption at this point that there is a straight pipe buried under the tub, inside the concrete that runs directly to my septic.

I am sure they are not coming down the vent as I have removed some of the plumbing behind this tub to make access easier for the snake I tried earlier and yet the flies are still there.

Thanks
 
Ok looking on-line I guess that was a stupid assumption on my part, all drains need the P trap, can someone give me a clue as to where this might be found on a bathtub.....near the faucet end, the other end, somewhere in the middle, would this trap be buried in the concrete along with the line exiting the tub or would these lines go down below the concrete foundation and be imbedded in the dirt?

I have noticed now that since snaking the drain ( which was a real bear ) that the flies have gone away but I am hesitant to say for good.

If Id of known that there was a trap I would have spent alot more time snaking it.

Why was it so difficult to get the wand down the drain? Is this typical on bathtubs?

From the get go it was difficult, assuming some pretty hefty bends/curves.
 
Even with p-traps on each fixture sewer flies can get in your home. The flies and their larvae feast on organic material in the pipes or septic system and can sometimes be seen in p-traps that are not used or flushed regularly. That's how they can get in. Flies lay their eggs on the outlet side of the p-trap and the larvae hatch on the inlet side. Since the vents are on the outlet side already, they vents are usually ruled out as an entry point unless there is a separation of a vent in a wall or a hole in a vent. A rare and unlikely possibility.
Flushing all traps in the house, including floor drains can help. If your septic tank is due for being pumped, removing some of the organic matter in the tank could also reduce the feeding/breeding grounds. I'm sure you don't want to disturb the bacterial balance in your septic by flooding it with harsh chemicals, either.
If you want to find out which drain they are entering in the house, before going to bed, covr each drain in the house with clear packaging tape...stick side down towards the drain, of course. In the morning you can check the tape to see if there is a specific problem drain that needs to be flushed with clean water or may be losing its trap seal, for some reason, and allowing the flies to enter. A clog or belly in a pipe or a blocked vent as well as globs of hair build up in the drain can be a cause of their arrival, since this is a new development in the past ten years. You've probably had sewer flies in the septic since it was first purchased, so something must have changed six months ago.
I'm probably going to catch a lot of flak for this next statement, but I will stand behind it; I have solved several issues people have had with drainage systems by installing a house trap on a septic or public sewer connection. That barrier of separation has more pros than cons, but that may be a last resort in your situation.
 
Thanks for the info guys, since snaking the pipe Sat. afternoon I have seen 3 flies so evidently I did some good. Typically I could easily go into the bathroom and see 2 dozen or more on the walls and within the bathtub.

Block home being built in 71 with a foundation......are the pipes within the foundation or buried well below?

What are the chances of breaking a pipe by me going back again and snaking again? What other alternatives do I have?

Evidently its looking like they are possibly not coming directly from the septic tank but instead have made a home somewhere between the tank and my tub.

I know if I still see these few than I have not completely gotten rid of where they have made a home so I am going to have to keep at it with something even if that means renting the snake again. Of course I do not want to damage any pipes in doing so.

What would the professional plumber be doing if he had this service call?
 
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I would flush all of the drains thoroughly with cold water for quite a while, then continue to have water running during the process of snaking the drains. If a belly or break is suspected, I would camera the building drain. Even before a camera, hydrojetting the drain could also come into play. If you are still seeing a few flies, you may want to try the tape trick that I mentioned before in case you have a single problematic drain. The sewer flies should still have a difficult time entering the home if the trap seals are good. I just had a call for sewer flies on Monday and found a floor drain had lost its trap seal. I flushed all of the fixtures with fresh water and mixed some Citrishield in a 5 gallon bucket of water to flush and prime the floor drain. This morning still no flies, so the floor drain was the culprit. I'll probably just prime it monthly with a bucket of water to keep it from happening again since there is no auto primer.
 
Thanks for the info Ill read your post a few times before commenting any further, good idea though on the running water while snaking.
 
I would flush all of the drains thoroughly with cold water for quite a while, then continue to have water running during the process of snaking the drains. If a belly or break is suspected, I would camera the building drain. Even before a camera, hydrojetting the drain could also come into play. If you are still seeing a few flies, you may want to try the tape trick that I mentioned before in case you have a single problematic drain. The sewer flies should still have a difficult time entering the home if the trap seals are good. I just had a call for sewer flies on Monday and found a floor drain had lost its trap seal. I flushed all of the fixtures with fresh water and mixed some Citrishield in a 5 gallon bucket of water to flush and prime the floor drain. This morning still no flies, so the floor drain was the culprit. I'll probably just prime it monthly with a bucket of water to keep it from happening again since there is no auto primer.

Can you give me some more info on trap seals, not sure where they are / if I have them / how to know if they are functioning properly.

When I snaked the pipe last weekend I noticed the snake had to travel a bit of distance ( just guessing but maybe 2 feet or so ) before it came up wet indicating what I am assuming is the area of the P trap, is this typical for the P trap to be this far down?

Are there any precautions that I should be made aware of before snaking the bathtub drain.

No need for the tape, I am fairly certain that the bathtub drain is where they are coming from.
 
Trap seal simply refers to the water inside he trap of a fixture that keeps sewer gases from entering the home.

trap.jpg
 
this is a typical set up under concrete for a tub. You may have lots of build up in the drain or hair which could also cause the loss of the trap seal. When you snake the drain, it's usually easiest to remove the over flow cover and run the snake down that way so you can go further with the cable and flush water down the drain as you auger it. You should be able to go further than two feet.

trapunderconcrete.jpg
 
After doing all the things the guys have mentioned here already. My Wife and I discovered that the flies were coming in through a bad wax ring. Replaced the ring and bye bye flies.

You being perfectly sure that it's the bathtub drain tells me that your wax ring is bad.:rolleyes: That's exactly how we felt, we just knew these flies were coming up through a shower drain because it wasn't used very often.
 
We have a bathroom around the corner which is used only for guests. We started getting these dumb flies in here and as a result, I ran water in the sink and shower for awhile, and now the flies are gone. I guess the traps must have run dry. Thanks for this thread!
 
Thank-you and everyone for the help, have not done anything more at this point, seeing very few flies, we have had a cold winter snap again so maybe that has something to do with their absence. Guessing in a few days they are going to be re-grouping and we will see them in full force.

Will update as the battle continues.
 
Number of lies has again been slowly increasing, today I came home and the numbers had tripled, I prob. killed ( no exaggerating ) 75 flies between the two connected bathrooms.

I am certain that they are coming from the one bathtub drain cause that is where they are most in numbers however I have placed tape over all the drains just to hopefully be certain that this is where they are coming out of.

Pictures below: I have to get to a solution for this, when they are smashed they leave behind a dark residue that does not simply wipe of paint.

Picture 070.jpg
 
Wow, those are pretty big flies.
I was thinking maybe they where tiny, like nats.
Interesting thread. 30 yrs of service work I don't think I was ever called out about flies. Sewer odors, yes. Flies you can see. I like that tape test.

Maybe you don't have a p-trap on your tub. If you are running a snake down your drain, you will know if you are in a p-trap because they are not easy to pass a snake through.
 
Just like my Wife and I. We were sure they were coming in from the shower drain. Nope, wax ring was the problem. It doesn't cost that much to change it. It may be worth the investment.
 

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