Common Problems Found During A Sewer Pipe Inspection

Date Published: July 1, 2019

Sometimes sewer issues go undetected until they do a good bit of damage to your home. As you might imagine, sewer lines need just as much attention and maintenance as other parts of your home. However, we tend to overlook them because we don’t know what we don’t see. If you suspect something might be going on with your sewer system or you are thinking about getting an inspection, this article will discuss the most common sewer inspection problems found during a sewer pipe inspection.

SEWER camera inspection, sewer scope inspection example video

What your sewer line should look like…

Sewer Inspection Problem #1 – Low Areas (aka) Belly

This is commonly referred to as a sag, low area or belly when debris collects in the low point and interferes with the flow of the system. This can cause a backup or blockage in your sewer line. A belly in your sewer line was likely the result of a poor layout for the sewer, or it has been impacted by some other event like a tree root (discussed below) or shifting soil weather events.

Minor bellies where standing water is present do not always need repair. In fact, a belly is a very common sewer pipe inspection issue. Your sewer scope tech will inform you if a belly is sloped enough to require action.

Belly found during a sewer scope inspection

The camera is fully submerged in water indicating this section of piping has a deep belly. This belly was caused by root pressure from a tree.

There are various ways to have this issue corrected with the help of a knowledgeable team. They can discuss what is happening in your particular line, which will determine their course of action to fix it.

The bottom line, however, is that the system will need to be unearthed to a degree to repair the problem.

Sewer Inspection Problem #2 – Offset Pipes

An offset is where two sections of pipes meet but do not line up correctly. Most of the time, an environmental change is usually at fault for an offset pipe. Settlement in the surrounding earth or root growth can cause the two sections of piping to shift independently. Occasionally the problem is due to poor installation, but this is rare.

If the offset is small, and it does not appear to be blocking the flow of waste, then no action is required. But if the offset is larger and specifically if it is near the bottom edge of the pipe, then repair is likely needed.

This issue can be a pain to deal with, and could cost you more money than you were prepared to take on. The reason for this is that a significant area will need to be dug up, including everything in its path, such as landscaping.

Ask your plumbing specialist about how best to solve the issues. Typically plumbers will look to replace that small section of piping if the rest of the pipe is in good shape.

Also, ask if your situation can be fixed with trenchless technology. This type of repair requires little to no digging. It involves lining the inside of the pipe with a plastic liner material.

Sewer Inspection Problem #3 – Tree Roots

Roots In Sewer Line Found In Sewer Scope Inspection Defect

Root intrusion in a cast iron line.

When your sewer system was installed, chances are the vegetation wasn’t mature and no one suspected that your system could be compromised by a tree root. Roots are relentless and powerful and can crush a pipe or offset it, creating all kinds of problems with the flow of your system.

Unfortunately, most people do not think about their sewer line location when planting a tree. Often we see trees planted directly above a sewer line in front yards.

Root intrusion is very common in older clay and cast iron sewer lines. Newer PVC lines have a lower chance of having root issues.

There are several ways to handle this issue, including replacing the old line with a more structurally sound one like plastic. You can treat the line with a poison that will make the roots retreat. You can also rent a power auger which will clean out the line and will need to be done on a routine basis.

There are also hundreds of rooter companies that will come out and run a power auger down your sewer line for a low fee. We recommend that you do this often if you have a clay line.

Looking for a highly rated sewer scope company in the Colorado area? If you are buying a home, or a current homeowner, our sewer scope professionals can help you understand the condition of your sewer line. Learn more about our sewer inspection services.

Sewer Inspection Problem #4 – Grease Build Up

Example of Sewer Line Problems: Grease Build Up found during a sewer pipe inspection.

Grease build-up found in a cast iron line.

Because of the use of garbage disposals in modern plumbing, a build-up of grease can occur in the line. Since the oil substances are not water soluble, the grease tends to stick to the sides of the pipe.

The grease can eventually lead to blockages if not cleaned out. Other materials traveling down the pipe can get caught up on these build-ups and inhibit the flow of waste.

Luckily, this is a pretty simple fix. When we find grease build ups we typically recommend a jet cleaning. This involves pushing a high-pressure hose down the pipe to clean off the walls. If there are roots present in the sewer line as well, a rooter may also remove a lot of this grease.

Sewer Inspection Problem #5 – Cracking

Piping cracks in clay and cast iron lines are common to see. Pressure on the pipe can cause hairline cracks around fittings and other areas.

Like most of these issues, if the water is not blocked, no action is needed. Cracks on the top and sides of the pipe typically can be ignored.

However, if the crack is on the bottom side of the pipe, you may consider adding a liner to the pipe to reduce leakage of sewage into your lawn. Leaks outside of the pipe can lead to further settlement of the sewer line.

Sewer Inspection Problem #6 – Pipe Collapse

A pipe collapse is uncommon, but it typically occurs on sewer lines that have been neglected. Pipe collapses are often found as a result of many of the issues we discussed above. Pipes can collapse because of vegetation, an offset, or can be weather related to old lines expanding and contracting.

As the pipe collapses, the opening shrinks and it is likely to cause a blockage. Further, the leakage occurring in the yard from the cracked pipe can exacerbate the situation. In most cases, the line will need to be fully replaced.

If a pipe is fully collapsed, our scope techs typically cannot go any further to inspect the rest of the line. Because of this, replacing just the problem section can be risky as there may be more issues down the line.

Ask your plumbing professional about the easiest remedy for your specific problem.

How We Locate Problem Areas

Once an issue is found in a sewer line, we use a special locator tool that can locate the head of the camera. The sewer scope camera is placed over the defect, and the tech will use the locator tool outside to pinpoint the location.

When the problem is located outside, we mark this area to give the plumber an idea of the issue.  This also gives the home buyer a clue as to how difficult the repair will be. Unfortunately, we do find issues under concrete walkways, driveways, and even garages.

Location a sewer line issue during a sewer pipe inspection.

Our scope tech using a locator to find a sewer line problem.

Bonus: An uncommon defect.

This list of 6 common items are things we see and deal with every day. You might think, “I am buying a brand new house, and there is likely nothing wrong with my sewer line.” This is typically the case, but does the cost of a sewer scope inspection outweigh the knowledge of knowing? Recently, one of our sewer technicians, Woodrow, stumbled across an unusual problem in a sewer line…

Rebar found within a sewer line during a sewer scope inspection

Yep, that is a piece of rebar that was hammered through the pipe. You can see the bottom of the pipe on the left. The rebar was likely used to brace a footer for a nearby deck. However, the builder was unaware of the presence of the sewer line below and hammered the rebar through the pipe. Not only does this line need to be repaired, but the deck post may need to be moved as well resulting in a costly repair.

This all was present in a nice PVC pipe that had minimal damage otherwise. So as unfortunate as this situation may be, it serves as an example that a simple sewer scope inspection can save you a lot of money and stress from hidden repairs, or give you the peace of mind knowing your sewage is flowing swiftly away from your home.


So now you know all you’ve ever wanted to know about sewer pipe inspections and common sewer line problems. It is very important to understand the condition of a sewer line before buying a home as repairs can be a major cost to the homeowner.

In many cases, a sewer line repair can be one of the most expensive repairs associated with a home. A full sewer line replacement can cost between $10,000-$30,000!

As with most home repairs, many of them can be prevented with maintenance. Sewers are never a fun issue to deal with, so try being proactive and schedule a Sewer Scope Inspection today.

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About the Author: Luke Griess

Luke Griess is an ASHI certified Home Inspector and Certified HERS rater, with over 20 years cumulative experience in the home inspection, residential energy services, and construction industries.

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