Sewer line replacement due to “negative slope”

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gregbartkiw

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Hi all, new to the forum. We bought a 20 year old home 2 years ago. I had a sewer company come in and do a camera inspection of my sewer lines. The technician found that below the kitchen stack, there was a large build up of soft grease for about 4 or 5 feet from the previous owners and that due to a “negative slope” in the line (-7) there was also some standing water. He suggested that we spend almost $4000 to have them come in and break up the floor and replace about 5 feet of the pvc line and correct the slope. Alternatively, they could “hydro vac” the line for $2100 but the problem could return because of negative slope…he strongly recommended the 1st option. I am wondering if these prices seem reasonable or somewhat excessive and wonder what you would do. Thanks for your professional opinions!
 
Unless I was having trouble with it, I wouldn’t do anything.

I wouldn’t use a garbage disposal and I’d run plenty of water through that line everyday. You can have the grease jetted clean…….

Have a good one 👍
 
Unless I was having trouble with it, I wouldn’t do anything.

I wouldn’t use a garbage disposal and I’d run plenty of water through that line everyday. You can have the grease jetted clean…….

Have a good one 👍
Thanks for the response. So you are saying the “-7” negative slope is not that big a deal? Only the kitchen sink and dishwasher are attached to that pipe. I agree that the 5 feet or so of soft grease needs to go and I guess the hydro flush is the best way to go but do you think $2100 is reasonable??
 
That’s too much. Jetting that line should be less than $500
 
Thanks for the response. So you are saying the “-7” negative slope is not that big a deal? Only the kitchen sink and dishwasher are attached to that pipe. I agree that the 5 feet or so of soft grease needs to go and I guess the hydro flush is the best way to go but do you think $2100 is reasonable??
Yes, that would seem more reasonable to me!
 
I wouldn’t do anything but flush with hot water unless I was having trouble on a regular basis.
 
I wouldn’t do anything but flush with hot water unless I was having trouble on a regular basis.
There is a lot of grease…I watched him scope it and the 3” pipe is probably half full for about 5 feet so it will be a problem at some point. The grease is fairly soft right now.
 
There is a lot of grease…I watched him scope it and the 3” pipe is probably half full for about 5 feet so it will be a problem at some point. The grease is fairly soft right now.
Ok, clean the grease out.
 
First off what does he mean -7. That isn't a way we describe pitch, 1/8" per foot, 1/4" per foot, 1/2" per foot. Also you just cant cut out a few feet and add pitch, because if the whole line has back pitch you have to go to where it is tied in. It could have a belly in the line, but like two said they are charging way to much. If it is a belly in the line I would just be mindful of what I put down the drain before I spent that much on it. Who did you use, some of these companies are notorious for trying to upsell. If you do move forward, do yourself a favor and get other opinions.
 
Ok, clean the grease out.
So I had another plumbing/drain company give me a quote for power flushing the grease out and it came in at $1800….flushing and then scoping the drain to be sure the pipes are clear of everything to the sewer. By the way, I am in Ontario, Canada. I am looking to get another quote at least!
 
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