What is a Sewer Scope?

Sewer Scopes

When it comes to a general home inspection, it’s important to understand what is included in the inspection and what areas are not included or what limitations there are. We joke that one good way to know what we can’t inspect is to remember that although our inspectors are super, they don’t have x-ray vision. They can’t see through a garage packed to the gills with personal property, they can’t see through a sealed attic, and they can’t see into the pipes of the main sewer line underneath a home. The exterior of all visible waste sewer lines are examined during a general home inspection, but the interior of the lines is not. 

A potentially extensive and expensive issue could be lurking beneath the ground, and the only way to evaluate the current state of your main sewer line is to conduct an inspection called a Sewer Scope. This is an optional add-on service where a trained technician uses a specialized, waterproof camera to see into and record in real time what we are seeing in the main sewer line.

I would like to address a few of the main questions we receive regarding Sewer Scopes, including why you should consider a sewer line inspection, how we access the main sewer line and what we need from the homeowner, and some of the common issues we find within the sewer line. 

Why should I get a Sewer Scope?

This is a very common question that is asked, since many people don’t understand what it is or why it is not included in the general home inspection. Since we’ve already answered those questions, I’d also like to add another fun fact that many people aren’t aware of: the homeowner is responsible for the sewer line from their home to where it meets the city connection. Wait, what? Yep – and it’s tricky because it’s something we can’t look out our front door and see and most of us don’t think about on a daily basis until something goes wrong.

So, we get it – inspections cost money and they cost time. Inspection periods are sometimes very short and the housing market feels like it may be too much a risk to add another potential bump in the proverbial road to home ownership. But, I may argue, a sewer line inspection generally takes less than an hour of time and can, a lot of times, be done at the same time as your general home inspection. As a home inspector, I am not able to see every inch of your home, especially those areas that are underground or behind walls. A sewer line inspection allows us access to the interior of the line from the line access all the way to the city connection. You receive a recording of the entire line from the home to the city connection, with commentary pointing out any obstructions or deficiencies found.

Where does a Sewer Scope even start?

Most of the time, the Sewer Scope will start at either the main sewer access or a floor access. Generally we will start at the main waste line access and look for the cap, which is usually a square head protruding from the main line. The line could be any number of colors or materials, but generally it would be made out of cast iron (black metal sections), lead (black or silver sections), PVC (white plastic), or ABS (black plastic). The cap could also be made out of any number of materials as well, depending on if the line has ever been accessed. If the cap has been replaced, it could be made of plastic, rubber, brass, or a combination of plastic and rubber. If we are able to remove the cap, we will start the inspection. 

There are a variety of issues we can encounter when attempting to remove the cap, and many times it is because we simply cannot access it. We have run into personal belongings blocking access, water softening systems, appliances, and some have even been fully enclosed into walls without any access being given to that area. It is a good idea to know where your access(es) are located in the event your line needs to be cleaned or repaired. It could become costly to gain access to your line if one is not readily available. 

Some other places we look for access are near the water main, near the exterior basement wall on the front of the home, or under the stairs. Sometimes, though not as common here in MN, we find access outside the home, generally near the front of the home near either a corner or the front steps. In my home, I have a rubber cap on my cast iron waste line and a PVC floor access in our basement bedroom. I have made sure these are readily available if ever needed.

What do you do if there is no main sewer access?

There are a few options available for us to try and gain access, and some are more intrusive than others. If a more intrusive method is needed, additional fees may be incurred. One way that is common is to access through a roof vent. A home’s drainage system needs to breathe and allow waste gas to exit the home, otherwise it will not flow properly. We all know how stinky that would be without one! If the roof is safe and able to be walked, a scope may be done from there. 

Our next option would be to remove a toilet from the home and gain access to the line from there. This most often will cost extra as it requires a technician who is trained to remove and replace toilets and it also requires the homeowner’s approval as we are now moving into a very intrusive act.

Some inspectors may use a floor drain as access, but this tends to be rough on the camera reel and is seen as a last resort for many. The final way would be to cut access into a line. This is very rare and would need to be done by a licensed plumber as the line would then need to be repaired properly. 

If you aren’t sure where your sewer line access is, it would be a good idea to locate it so that in the event of an emergency, you can get to it quickly. 

What do you look for when you inspect the line?

In a sewer line inspection, we report on all sorts of things such as waste line material, length, where we inspected from, if the home is vacant or not, among other things. Why is this information important? For example, knowing the material will help us understand the line’s vulnerability to certain issues. Also, the longer the line, the more opportunities for issues to  potentially occur. So what do we look for? As we inspect the line on the way to the city connection, as well as on the way back, looking for cracks, chips, breaks, root intrusion, offset joints, debris build up, scale build up, any potential previous repairs, low points within the line or anything that could cause a potential back up. 

Common Observations:

• Root Intrusion – This happens when roots from trees or plants enter into the line through the joints of the line. This is mainly found in cast iron, clay, or cement lines, but can be found in other types of line as well. Root intrusion leads to areas of entrapment for debris to be caught and cause slow draining or stoppages. If left untreated, root intrusion can cause damage to the actual line leading to potential costly and invasive repairs. If there is root intrusion in a PVC or plastic line, there may be other issues that need to be addressed.
• Offset Joint – In waste lines that are made up in sections such as cast iron, clay, and cement, the joints are mostly slipped into place, sometimes using a gasket to help seal the joint. Over time, these joints can become loose or shift causing a step or “speed bump” in the line. Offsets can occur from heavy root intrusion, softening soil, or just old age, among other things. Repairs for offsets can vary in price and scope depending on severity.
• Chips, Cracks, and Breaks – These can occur from improper installation, unstable dirt, improper maintenance, or putting improper items down the line. If a line continues to chip or crack, it could lead to potential catastrophic failure of the line.
• Scale Build Up – This happens naturally as all water contains minerals that are deposited onto the line over time. If your area has hard water, this can also lead to scale build up, especially if your home has cast iron or galvanized waste lines. Metal will corrode with normal use and will build up over the years, but can be accelerated with heavy use or improper maintenance.
• Low Points/Belly – These are just what they sound like and are a section of the line that is lower than the rest, and can lead to slow draining, clogging, or even further damage due to the extra wear and tear on that section of line. This can happen due to soft soil, cracked or broken lines, improper installation, or from improper maintenance.
• Debris Build Up – I think the easiest to picture is when root intrusion causes debris to get caught on the tree roots and builds up causing a blockage. A similar thing can happen when items that should not be flushed are flushed down the drain and get caught. There are a few things that a lot of people think are fine to put down the drain, but generally not recommended to do. 

Things that should NOT be put down your drains:

• Paper towels – These do not break down like toilet paper does and will stay within the line for too long, especially if there is root intrusion within the line.
• “Flushable” wipes – Flushable wipes are not truly flushable, especially in older lines, as they tend to get caught and disrupt flow.
• Feminine hygiene products – These products tend to swell with additional water and are likely to get caught on any other debris in the line. 
• Dental floss – This is similar to certain feminine hygiene products in that strings tend to get caught on other debris within the line.
• Grease – As grease cools it also solidifies within the line causing a high spot that may continue to build and restrict the flow of waste. When waste is slowed or restricted, that could lead to potential backups into the home. It is recommended to refrain from putting grease down your waste line and dispose of it properly. 

The Wrap

If you are purchasing a home, even a new build, a Sewer Scope will give you a better indication of the current condition of the line and insights into potential future issues to be aware of. If an issue is found, it can be repaired, and it is always better to find current issues or potential future issues before they become major issues. If you currently own a home but have never had your line inspected, it could be a good idea to consider having one done by a certified sewer line inspector or give us a call here at Marigold!