We cannot get rid of drain/sewer flies. They are apparently breading in the dirt under our slab floor.

We treated our sinks and drains for 2 years to no avail. Our plumbers finally suspected a cracked pipe; there were several: the toilet pipe, the bathroom sink pipe, the kitchen sink pipe (which is under the ground floor slab) and a pipe outside of our house. All of these pipes are ground level under a slab foundation. Apparently our kitchen sink and dishwasher were draining under the slab. Our entire plumbing system on the ground floor was excavated and replaced with plastic pipes, including the pipe under the sidewalk outside. The crack in the kitchen sink pipe was more than a foot long. We're of course not sure how long the sink was draining under our house (we've owned the split level home for 6 years, it was built in 1961).

It has been about 3 months since the plumbing has been replaced and we're still seeing flies. They're in our basement and they're still in the ground floor bathroom (which is gutted now because of this problem, we're waiting to get rid of the flies first).

We are now using fly strips and have used a 'fogger' twice. I've called a few exterminator companies. One exterminator said the source needs to be found and is most likely in the dirt where the broken pipe was; he would treat the dirt with a non-toxic solution by drilling holes in the slab (we tried this). The second exterminator said to use a fogger and fly strips; we did this and in less than 24 hours the fly strips contained about 50 or more flies.

Should we hire professionals to remove the dirt from under our house?

I don't know what to do. We've moved out of our house for months now; I have two small children.

Can anyone please help us?

Baby,
Go back and read the thread on this page titled "Drain/Sewer Flies". I left several articles on controlling and eliminating drain flies. If you need more information click on back. Good luck and I can really sympathize with your problem. I just got rid of mine.
Tom

We are having a problem with sewer flies mostly in kitchen but we have seen them in bathroom also please help thank you

Here's some information that may be helpful. I had a drain fly infestation that was eliminated when my sewer was Hydro Jetted by Rooter Man of Sarasota. Blew all those little suckers up into my shower where I sprayed and killed them. That was three months ago and they haven't been back.
Moth or drain flies are small black flies which
Thrive in drain pipes and sewer lines. They need
A lot of moisture to complete their life cycle.
Drain flies do not fly well. They tend to drift
And seem to float along more than fly. Their
Wings are shaped like a leaf of a plant and one
Can see hair like fibers on all parts of their
Body which is why they are also called moth flies.
I have dealt with drain fly infestations in
Many homes which start in the sink or bathroom
Shower. The drain lines which have the most
Activity seem to be the ones most likely to have
An infestation. I have also observed that homes
With septic tanks seem most likely to get them.
I am not sure if there is some kind of build up
Which occurs more with this type of drainage
Or if there is something in the tank which allows
These flies to prosper. Although these homes
Seem more likely to get drain flies, once the
Cycle begins it takes place in the home. I have
Encountered several infestations where the larva
Were found crawling out of shower or bath tub
Drains. The homeowners thought they were some
Kind of leach. In fact, the larva of drain flies
Thrive in a slime buildup which is on virtually
Any drain pipe which is used a lot. This slime
Enables the eggs which are laid to be protected
And sheltered. The eggs and hatching larva
Embed themselves in this slime so they don't wash
Away. The cycle of these flies takes around
A month to complete. Don't waste your time with
Bleach or other cleaning solvents. Showers and tubs
Which have ceramic tiles may also supply a moist
Slimy environment in which they can live. Sump
Pumps and wet crawl spaces are other environments
Where I have seen them live. Drain flies can be harder
To control than other small flies. Although
There are several products to kill adults, the
Key is maintaining and minimizing their breeding
Areas. This could prove to be difficult and
Ongoing.
Like most flies, there are several products
Available for their control. Use a "SPACE SPRAY"
For immediate relief of the adults. There are
Several to choose from in the section below.
This will quickly control the adults, but the
Secret to getting rid of them is to use a
Product we sell which removes the slime build
Up on drain pipes. By removing this slime, the
Larva cannot develop. This will stop the cycle.
In the "SURFACE SPRAY" section below, look for
The product called SURVIVORS. This is applied
Down drain pipes and will remove the nest sights
These flies need. You may also use the product
Called PT-CYKICK which is located in the same
Section. It is ideal for treating in cracks and
Crevices where these flies like to lay eggs. Such
Cracks will develop around ceramic tile, windows
And grout joints.
Good luck, Tom

Keep your traps wet, including in showers, tubs, sinks and floor drains. Make sure all Clean Outs have plugs.