Sewer Line Repair/Replacement


What is a Main Line Stoppage?

Every drain in your home – your sink drains, shower drains, tub drains, washing machine drains, and toilets- are connected to your home’s main sewer line.

When you wash something down your sink, take a bath or shower, wash clothes, or flush your toilet, that waste water goes down a vertical drain line that ties into a larger horizontal main line.

Main lines are sloped so that gravity carries waste water down your main line and into a public sewage or septic system. But if your main sewer line becomes clogged, your waste water will eventually have nowhere to go except for up through another drain in your home, referred to as sewage backup.

First floor tub drains and first floor standalone shower drains are almost always where homeowners first notice sewage backup because they are the closest drains to the main line. If your home doesn’t have a tub or shower on the first floor, then the toilets on the first floor of your home will make gurgling noises, and possibly overflow with water whenever you take a shower, use a sink, or wash clothes or dishes.

What Causes a Main Line Stoppage?

Main line stoppages are always caused by an obstruction in your main line, and there are several main line obstructions we see over and over again:

Build-up in a Bellied PVC Main Line

Remember how we said that main lines slope so that gravity carries your home’s waste water to a public sanitation system? Well, sometimes this slope gets a belly, or dipped section of pipe, especially if it’s a main line made out of PVC.

Channel Rot or Broken Cast Iron

Before it became standard for main lines to be made out of PVC, they were mostly made out of cast iron that tied into a concrete main line before reaching the public sewer system. If your home was built before the 80s, it more than likely has a cast iron main line.

Tree Roots Intrusion of Main Line

In older homes, it was common to have a cast iron or ABS main line that turned into a concrete main line after passing the edge of the home. Concrete main lines are made out of sections of concrete pipe that connect using bell and spigot joints.

Clearing a Main Line Stoppage

Before we attempt to clear the stoppage, we try to identify roughly where the stoppage is occurring in your main line, either under your home, or under your yard or driveway. We do this by noting the location of each fixture that’s backing up and by opening the two-way cleanout outside of your home. If the two way cleanout is also backed up, then we know that the stoppage is somewhere past that point in the main line and can run a snake cable from there. If the two-way cleanout is not backed up, then we run our main line clean-out cable through a drain in your home.

When we run a cable in an attempt to poke a hole in the stoppage, eventually one of two things will happen: 1) We will hit the stoppage, poke through it, and then the water from your backed up drain will begin going down or 2) We will hit a tough spot indicating to us that we have either hit mud from channel rot or a root ball. If we hit a tough spot, we can usually tell if it’s mud or roots. And if it’s roots, we will use an attachment and attempt to pull some of the roots off, allowing water to drain. If it’s mud, we know we’re probably dealing with channel rot or a hole in your pipe and will recommend a reroute.

Visually Inspect the Main Line by Running a Camera

After we have poked a hole through the stoppage and allowed water to start draining again, we will ask to run a camera to make a visual inspection. A visual inspection will give us a better idea of where the stoppage is occurring and what’s causing it so we can find the best solution.


Typically, after doing the above three, we will have solved the immediate backup issue and identified what caused the main line stoppage in the first place. After this, we highly recommend moving forward with replacing or fixing your main line so that a stoppage won’t happen again anytime soon.

Main Line Repair & Replacement

To permanently fix a main line and prevent recurring stoppages, we have to dig.

Now, whether we’re simply digging a trench or actually tunneling under your home depends on where the problem area is. For instance, if we find out during our visual inspection that the cause of your main line stoppage is tree roots, then we will dig a trench, remove the concrete pipes, replace them with schedule 40 PVC, and tie them into the city line. But if we find that the problem is a bellied PVC pipe or channel rot occurring underneath your home, then things get a little trickier.

Tunnel Repair

To fix any length of pipe under your home, we have to dig an access tunnel. Sometimes, all that’s needed is a spot repair, which is when we fix a little section of pipe. For instance, if we determine from our visual inspection that your main line stoppage is occurring right next to a fixture, like a tub or a toilet on the edge of your home, than we only have to dig a small access tunnel. But if your main line has a belly in the middle of your home, we need to dig a long access tunnel and either reslope the pipe or completely replace it. In instances where the problem is cast iron channel rot, we will replace sections or the entire main line with schedule 40 PVC.

Main Line Reroute

When we’re running a cable down your pipe to clear the stoppage, if we hit mud, we recommend a reroute. Why? Because mud indicates that there is a hole in your main line, and it’s almost impossible to patch a hole in an underground pipe. So the easiest solution is to reroute.

For a reroute, we cap the old line and build a new one running from your fixture to the outside of your home and then back underground. We either tie this rerouted line past the area that’s rotted through on your main line, or we reroute and replace the main line completely. Best Choice always uses schedule 40, solid core PVC in our reroutes, and we try to use a thicker diameter pipe with steep slope to ensure your waste-water can easily flow down your main line and get where it’s going.