Our plumber came to replace a valve on our main shot off line and while there found evidence of "sewer flies" around the sewer line where it exits the house into the front yard. We had been noticing flies in the basement and could not determine where they were coming from so it was interesting that he mentioned that without us asking. He said that since there was no evidence of water but just the flies there probably was a small crack on the line that would not be detectable with a camera. He also mentioned that the crack was probably no more than 4 to 5 feet from the house (otherwise the flies would not be able to live and get into our basement). He suggested as a temporary measure to caulk (sp?) around the pipe but that we probably wanted to replace the pipe at a cost of $5k (partial replacement) and $10k for replacing the line all the way to the public sewer junction. My questions are three. First, how much urgency do I need to give to this? Second, should I still use the camera to see what they find? Third, what is the likelihood that there isn't a crack on the line (could the flies just exist and be blocked out)?

With a job like this its best to get 3 estimates and evaluations from reputable plumbers in your area. I would not go with anyone who starts quoting the work without putting his camera down the line. The guy you spoke to may be correct but he is guessing at this point.

I agree wuth Bob,
I just went through the same thing. Sewrer/drain flies can get in your lines without a break in the line Your plumber has no clue as to what's going on under the slab so how can he shoot you a price. I wouldn' trust a plumber that attempted to hijack five grand from me with out a shred of proof that I needed the job done outside of "I think or I believe". I did have a break in my sewer main right along with sewer flies, While sewer flies live in the sewer pipes they breed in the drains above the trap also. Instead of a repipe job I opoted to reline my sewer main and saved, not only the hassle of having my house torn up but, the cost of a repipe job which would have cost me twice as much and the reline job was done in a days time as compared to days spent repiping.
None, until you know more facts. Your plumber jumped the gun and is attempting to scare you into a pricey job that you probably don't need.
I personally don't think you need to "sewercam" your main but if you're worried and it will give you peace of mind rhen go for it.
In my book the likelihood is that your sewer lines are just fine. I.'m a great believer in," If it ain't broke don't fix it" Read on to learn about sewer flies.
Moth or sewer/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 that's on the market 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

I agree with tom and bob, First off you aren't having problems with your sewer right?Why would you dig up your yard,because you have flies, doesent make sense to me.As tom said if it worries your that there's a crack in your sewer line get it checked.Our local guy charges 300 clams to do this.Remember if the break is on city property it's there problem,not yours :).If the break is on your property well then you assume the bill.5 k sounds like a lot of cash to dish out for this job to me, how to I no, that's what I do for a living, I own 2 back hoes and a couple trucks.I did a new sewer line 2 yrs ago for the ambulance company here in town for 15 k, we ran 700 ft of 6" from the building right to the main sewer.I no its hard to compare prices but for 5k I can do a lot of work.Digging up your yard to change a section of pipe should take less than 1.5 hours,that's at a 8 foot dept.Change out the section of pipe in 1.5 hours,back fill in .5 hours.Add an hour for unmentionables and your still looking at half a days work plus material, that doesent add up to 5k ;).Good luck.

Hey Maple leaf you from NEWFOUNDLAND?

Hi,snipes, no I am from northern ontario but if you have the same problem I probably could fly there,rent a hoe and still come in under 5k,lol.

I just thought you might be. You said a cold place and I thought that was a "fog devil" in your avatar. But I do have a sewer problem!

What's your problem snipes,have you posted it on here some where? You can email if you haven't or just post it and there are a few good people on here that really no there stuff,Tom and Bob are about the best you can get.

I am not sure of my problem yet just noticed it today in a house I am buying guessing it's the main line. I tried to emai lyou but there was no contact info in your membership thing. Once I get the details I will let you know and if you want to email me your address in the meantime that would be good too... I don't want to ruin this thread!

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