Broken sewage lines can cause a back-up into the house, but also cause underground pollution outside the house. They do need to be fixed as soon as it is identified that there is a problem. When the line is destroyed by crushing, or shifting ground, or a tree root that has crushed it through expansion, you have to dig it up and replace it. But if it is just backing up and leaking because of tree roots constantly coming through joints, there are alternatives to digging it up.
Allen in Oakville, Ontario has asked if new pipe or an epoxy liner is the best way to go.
Ok, new pipe we all understand. You dig the yard up, take out the old pipe, put in a new one, put the soil back and then repair the damage to the landscaping, sidewalks, roadways.
An epoxy liner is a really interesting process. You see the end result in the graphic above. First the line is cleaned out with a rooter. Then the pipe is inspected with a camera to be sure that there is a full sized passageway to the city sewer line. If all is good, then a rope is run down the line into the city pipe and caught downstream at the next man-hole cover. This rope serves to pull through a rubber bladder with an epoxy soaked cloth like pipe that is folded into a fairly small package. When this long sausage is in place as one continuous unit all the way from the house to the city line, air is pumped into the bladder. This forces the epoxy soaked liner out to hug the walls of the old pipe. When it becomes rigid, the bladder is deflated and pulled out of the middle. You now have new pipe with no joints to invite new tree roots the full length of the pipe. The end result is far better than a new pipe, with no disruption in the yard and a cost of anywhere from the same price of pipe replacement to less than half, depending on the job. The pipe in the photo came from Phil Groves Sewer Services in Hamilton, Ontario.
So Allen, my answer is to get both bids, and as long as the epoxy does not come out significantly more expensive than replacement, I would go for the epoxy. It will give you fewer problems down the road.
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