Warning Signs of a Main Sewer Line Clog

The most dangerous clogs happen in the main sewer line. The main sewer line is the pipe in your home that all other drains lead to. Sewer clogs can lead to sewage backup coming out of the drains, and lead to expensive sewer line repair. These clogs may be unseen, but can cause extensive damage to a home. If you have a clog in your main sewer line, it’s not safe to run any water in your home because there’s nowhere for the waste to escape to. To avoid sewer clogs, pay attention to these warning signs:

Clogged Drains or Toilets

The most common warning sign to a sewer line clog, is a clogged drain or toilet. If water is backing up, draining slowly, or a gurgling sound is coming from the drains, it is a sign that there’s a clog. Clogs can occur in the main sewer line or one of the secondary lines. If it’s the main line, any water run throughout the house with cause problems; if it’s a secondary line, it will be isolated to that one location. Common sources of clogging are feminine hygiene products, paper towels, or certain types of toilet paper. Avoid flushing these items to help keep your pipe lines clear.

Natural Causes

In older homes, tree roots can be a big cause of clogged sewer lines. Tree roots grow underground and can sometimes grow into sewerage lines, or even crush them. Roots are attracted to growing near sewer lines because they can soak up the moisture and continue to grow. Also, the earth can settle underneath the sewerage pipes in older homes, causing bellies or dips in the line. This can wear out pipes or cause thinning, which can lead to pipe damage and backups.


Another warning sign for clogged sewerage lines is if there is pressure in the pipes. Leaving a clog unattended can lead to increased pressure in pipes, resulting in a crack or burst. To avoid this pressure, 1-2 times a month, fill your sinks to the top and then drain them. The water pressure will move through the pipes and remove any waste that’s in the line.

Clogged sewer lines cannot be ignored. If you think you may have a sewer line clog, contact Boston Drain Company at 617-265-8888 today!

Posted in Sewer & Drain Blog.