Common Sewage Back-up Causes

Sewer back-ups are not anyone’s idea of a good time. They can be nigh on catastrophic, and let’s not even talk about the smell. Many homeowners that have been on the receiving end of sewage system backups want to find out what exactly causes this plumbing horror show and, even more so, how they can try and prevent them. Sewer line backups are typically caused by one of the problems we will be looking at in this article. They can either occur in the city’s main sewage pipes or your home’s sewage system.

What Is a Sewage Back-Up? 

Apart from being disgusting, a backup of a home’s sewer system happens when a sewage system becomes swamped due to severe rainfall or a blockage or clog in the sewage pipe. The waste material builds up and can be pushed back through the pipeline right into your home—through basement drains, toilets, and even the shower head. Worst. Shower. Ever! 

This obviously causes property damage, but it is also harmful to one’s health because sewage is heavily polluted. 

It is not safe to clean up sewage that has overflowed into your home by yourself. Pollutants in sewage water range from viruses and bacteria to chemicals, mould, pesticides, and other types of biohazardous waste. If you find yourself in the unfortunate situation of having to deal with sewage spilling everywhere, you will need to call in the experts. 

The Causes Of Sewage Back-ups


A clog in your sewage pipe is the most frequent cause of sewer backups. In the same way, you get a clog in your sink or toilets pipe, and so can your main sewage pipe, resulting in sewage backups in your home.

Clogs occur when materials with no business in a sewer pipe land up there and accumulate—things like oil, grease, hair, paper towels, etc. Click here for more information on the things you should never flush into a sewer. Thank us later. 

Trees with Aggressive Root Systems

Think of it as Mother Nature getting a bit of payback. Aggressive tree roots are also one of the more common causes of sewage backups. Tree roots are constantly looking for water, and your home’s pipes are a plentiful water supply. 

Tiny plant and tree roots can work their way into your piping systems and cause havoc on your sewer pipes as they grow and expand. Tree roots can jam up lines, grow through them, or even wrap around your sewage pipe and crush it. This is especially prevalent in homes with old pipes. 

Even if you don’t have any big trees or bushes on your property, roots from adjoining yards can also do a thorough job of blocking your sewer line and pipes. 

Sewer Lines That Have Broken or Eroded

The older your residence, the more probable it is that you’ll need to repair or replace your sewer pipe, as they are prone to cracking or collapsing as they get older. While older pipes are typically made of sturdy substances, they do not last indefinitely, as much as we would like them to. 

Combining Multiple Pipelines

Don’t ever hook up any additional water sources to your sanitary sewer line. Sewer pipelines are built to remove small amounts of wastewater from your home. Trying to combine rainwater and snowmelt runoff with a raw sewage line is really a bad idea because it will lead to a backup and overflow. 

While gutters, downspouts, and sump pumps can be attached to storm sewers, trying to connect them to sewer lines is dangerous, if not illegal.

City Sewers Causing Back-Ups

While you have some control over the causes mentioned earlier, there is not much you can do when a city sewer backs up. City sewers are susceptible to the same issues as your own sewage pipes. They can become obstructed and wear out. It’s not always easy to tell if the problem is with your sewer line or the city sewers.

Blocked-up city sewers tend to affect a few houses on the street, but that’s not always the scenario. On the bright side, if your neighbours are affected too, at least you won’t be suffering alone.  

Tips on Prevention 

Take care of your sewage pipes, and they will take care of you. This applies to both your home and the city’s sewage pipes, as they are all connected. 

  • If something is not meant to be flushed down the drain or toilet, don’t flush it. Sewage systems are relatively delicate and don’t react well to things other than water and TP. 
  • If you feel your pipes are old and haven’t been inspected for damage in a while. Do it. 
  • Clear your sewer line every 3 to 5 years to prevent blockage and debris from building up.
  • In open floor drains, install floating backflow drain plugs.

Things to Look out for if you suspect a Sewage Back-Up 

Now, on their own, these things are a problem that you need to fix as soon as possible. If you see that they are starting to multiply, it’s time to check your sewage pipes! 

  • A few drains in your home are blocked up or drain slowly.
  • Your drains smell really bad, particularly when water is running in other parts of the house.
  • When you flush the toilet or take a shower, or use taps, water sputters.
  • Your lawn is wet and spongy or smells bad.


Sewage backups are a homeowner’s worst nightmare due to the extensive damage they can end up causing to a household. Not to mention the health threat they pose to the people in your home. Knowing the causes of backups and taking sensible precautions will assist you in keeping your home safe and clean.


Johnson Plumbing is a dependable and trusted name in Reno, Nevada. Our licensed plumbers will follow all standards and guidelines while remaining on schedule. We’ll work with you to ensure that your home runs as smoothly as possible. We provide reliable proposals that eliminate the need for guesswork. We’ve prepared for a number of situations and are willing to stay until the work is completed at no extra charge.

Contact us for all your emergency plumbing needs. Our team is available 24/7

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