Nicolette Forbes

By: Nicolette Forbes on June 3rd, 2022

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Do I Need to Replace My Sewer Line?

Plumbing | Drains

Knowing the ins and outs of your sewer system is key to prolonging its lifespan, but how do you know if it's time to replace your sewer line? If everything seems to be going well, it's easy to ignore the warning signs before the big break or a disaster. So how do you start to identify these warning signs before it's too late?

With over 100 years of combined plumbing experience, we know a thing or two about plumbing. Having senior drain technicians who have been working on sewer lines for over 30 years, we have experience in several plumbing areas like wastewater and repairing or replacing a sewer line.

In this article, we’ll discuss: 

  • What a sewer line is
  • Signs it’s time to replace your sewer line

By the end of this article, you will have all the knowledge you need to better identify if it’s time to replace the sewer line before an emergency happens.


What is a Sewer Line?

Before we dive into possible issues with a sewer line, let’s first define what it is. A sewer line (also known as a mainline) is the pipe that goes from your home to the city connection or the septic tank. All of your home's water waste runs through a sewage line. That means everything from your garbage disposal to your showers goes through here. Many think of the mainline as the highway of your home's sewage system where smaller drains connect, just like roads.

Sewer Line going to a house

This line exits your home through the yard. It then links up with the city sewer system or your septic tank, if you have one. You'll know if there's a clog in the line since every fixture in the house will be affected, making it a big “uh oh” moment.

There’s a lot more information left to share about a sewer line and how it works in your plumbing system but we don’t want to stray too far off-topic. We are here to learn how to tell it’s time to replace a sewer line. Read this article here to learn more about what a sewer line is and why it’s important to maintain your pipes.

Now that we’re familiar with what a sewer line is, how can you tell if it is time to replace your sewer line? 


Signs It’s Time To Replace Your Sewer Line

There are several ways to tell if it is time to replace a sewer line: 

  • Old Age

Perhaps one of the most straightforward ways to tell it is time to replace your sewer line is old age

As they age, pipes tend to fail more frequently, but this is particularly a risk for old pipes made from outdated materials like cast iron. Typically, you can tell that your pipes are old by the age of your house or if you are experiencing frequent backups. If your sewer line has anything other than ABS Pipe/Liner, it may be time to consider replacing your line if it has outdated old Cast iron or clay pipe.

  • Frequent Clogs

Are your drains constantly and clogging for some strange reason? Then you may need to replace your sewer line. Frequent clogs are a major warning sign that there are issues with your mainline. If unaddressed, sewage could potentially come back up through your pipes. 

There are a lot of different things that can clog your drains and pipes and a blockage every so often is relatively normal. But if you’re noticing frequent clogs, it's probably time to get your sewer line looked at.

  • Roots

Roots are a leading cause of pipe damage and, like an iceberg, there's a lot more going on under the surface. Just like the iceberg that sank the Titanic, tree roots can be the demise of your pipes. A tree’s roots can often extend far beyond the reach of the branches visible aboveground, including into your sewer line. 

As trees grow and their roots dig into the ground, they can wrap around and choke pipes, leading to breaks in your pipes and clogs. When this happens, the root needs to be cut and the sewer line will likely have to be replaced.

Learn more about how roots affect your plumbing system and how it affects your plumbing system here. 

  • Strange Sounds/Smells

Uh oh! Do you hear strange noises and smell terrible odors in your home? No, it is not a swamp monster ready to attack. It is another sign that it may be time for you to replace your sewer line. When a sewer line breaks, it releases a nasty stench that can spread throughout your home.

There’s also the noises. If you hear bubbling or gurgling noises in your toilet bowl, it’s a sign of a blockage in your sewer line.

  • Slow Drains

Every homeowner deals with the occasional slowly draining sink or tub and you just plunge it out to drag out whatever is causing the clog. If you notice that your drains are constantly slow or that it’s happening often, it can be a sign that there is a big issue with your sewer line.

A single slow drain every now and then is common, but if every drain in your home drains slowly, we recommend that you call a plumber to see what’s going on.

Slow draining sink


To Replace or Not To Replace? That Is The Question

We discussed what a sewer line is, the signs to look for when it is time to replace the mainline, and the with a replacement. Knowing the ins and outs of your sewer system is key to prolonging its lifespan. Now that you know the key warning signals to watch for, you’ll be ready when it is time to take action. 

Read the articles below to learn more about the the benefits and drawbacks of hydro-jetting and snaking your pipes, along with how household drain cleaners can actually do more harm than good on your pipes.

Is It Bad To Snake My Pipes? 

Hydro-Jetting: Is It Bad For My Pipes?

Is Drain Cleaner Bad For My Pipes? 

Your plumbing system is a complicated place, and we here at Monkey Wrench Plumbing know a thing or two about plumbing. Having helped thousands of clients since 2007, we have experience in several plumbing areas including knowing the signs it’s time to replace your sewer lines. 

If you live in the L.A. area and are experiencing any issues with your drains or are interested in a camera inspection to see what’s going on underneath your home, hit the ‘Book’ button below to request an appointment. Or if you have any other questions regarding any of your plumbing needs, you can call us at 310-853-8690, and one of our call center representatives would be happy to help you.