PVC is the right pipe. It does not root. It does not corrode. On paper, a new PVC sewer line should last for decades without a problem. But the pipe is only part of the story. How it gets installed matters just as much as what it is made of.
We see problems in newer homes in Duluth and Superior on a regular basis. Here are the three most common reasons new sewer lines fail before they should.
A belly in the line from improper backfill
If a trench is over-dug and has a low spot, and the pipe is set in without correcting that first, the pipe follows the shape of the trench. Once it is backfilled and the ground settles, that low spot becomes a permanent sag in the line.
Sewer lines move waste by gravity. A belly holds water and debris and becomes a point of repeated blockage. We find these in lines that are only five or ten years old. The pipe is fine. The grade is wrong.
Joints that were not glued properly
PVC sewer joints are glued together. Done correctly, they are watertight and rigid for the life of the pipe. Done in a hurry, in cold temperatures, or without enough primer, the joint can fail. A loose or leaking joint is an entry point for root intrusion and groundwater.
This kind of problem usually does not show up on the surface. It is invisible until a camera goes through the line.
The frost problem at cleanouts
Every sewer line needs a cleanout every hundred feet. This is a Y-fitting on the main line with a standpipe that comes up to ground level, capped off so the line can be accessed for inspection or cleaning.
In Duluth and Superior, frost is the problem. When the ground freezes, the frost works its way down and swells as it goes. If that standpipe is backfilled with clay or compactable fill, the frost grabs it and pulls upward. That force transfers to the Y-fitting below and eventually breaks it loose from the main line.
We have fixed a lot of these. The right approach is to sleeve the standpipe. You run the 4-inch standpipe inside a 6-inch outer sleeve. The frost grabs the outer sleeve and cannot transfer that upward pull to the inner pipe or the Y-fitting underneath. It is not complicated, but it requires knowing that this is a problem in this climate, and taking the extra step during the original install.
What to do if you are in a newer home with sewer problems
If your home is less than ten to fifteen years old and you are having recurring drain issues, the pipe material is not the problem. It is almost always installation. A camera inspection will show exactly where the issue is, whether that is a belly, a joint failure, or a broken cleanout connection.
We offer free camera inspections on all service calls. We will run the camera, show you what we find, and give you a clear set of options before anything gets decided.
If you are in an older Duluth or Superior home and are seeing different symptoms, read our post on the signs your sewer line is failing. The causes are different but the starting point is the same.