5 Main Signs of a Collapsed Sewer Line

Are you looking to find what are signs of a collapsed sewer line? Keep reading to find out.

We use the plumbing systems in our homes without thinking too much about them. We overlook how these inventions have bettered our lives drastically by ensuring hygiene and proper disposal of waste. As a result, our homes are more comfortable and our health has improved significantly. All these achievements are possible due to modern plumbing systems.

You don’t think much about where waste goes until you face a problem such as collapsed sewer line under house. [1]

This is where you probably become interested in how your plumbing works. You will want to know how to tell if sewer pipe is leaking and how to repair it.

Before you check for signs of collapsed sewer line under house, let’s find out more about this important underground pipe.

What is a sewer line?


The main sewer line is precisely what you think it is. It is the big pipe that collects all the wastewater from your home to the main sewer under the street. The main sewer channels all the waste from sinks, toilets, and tubs from your home.

Even if the sewer line is connected to the city sewer system, you are the one responsible for potential problems. Whether it’s a blockage or worse, a collapsed sewer line, you will have to call the plumber. You will have to get the problem fixed at your expense.

The most common types of sewer lines

Depending on the age of your home, it will have a different type of sewer line. All types are functional, but each comes with its specific problems and repairs. [2]

  • Clay sewer lines

Clay pipes are the oldest types of sewer lines and are found in older properties built before the 1950s. The material is actually called vitrified clay pipe (VCP) and is made from a mixture of clay and shale. The blend is set at a high temperature to transform it into inert ceramic.

Clay pipe has a long lifespan, but is susceptible to root infiltrations. Their joints are not reliable against water and tree roots are attracted by the leaking water. The result is sewer line damage. Regular sewer cleaning is recommended to eliminate invading roots.

  • Cast iron pipe sewer lines

Also found in old homes, these sewer line type is better at protecting itself from roots. It can also withstand ground movement such as earthquake and cold.

But nothing is perfect, and even sturdy cast iron pipes rust and corrode in time. With severe rusting, entire portions of the sewer line can collapse.

  • Orangeburg sewer lines

This kind of pipe is made from bituminized fibers of wood pulp and pitch, pressed together. Their popularity soared in the 1800s, with Orangeburg being used late into the 20th century (as late as the 1970s). Its main advantages were the small weight and the easiness of use. [3]

Drawbacks of this sewer line type include the tendency to fail due to the brittle nature of the material. Most plumbers recommend replacing Orangeburg even if you don’t have any problems.

  • PVC sewer lines

The most common type of sewer line pipes today is plastic (polyvinyl chloride). PVC provides the largest number of advantages compared to other sewer line types:

  • Lightweight
  • Easiness of use
  • Resilience
  • Relatively good resistance to root penetration
  • Long lasting

Potential problems are caused by severe ground movements and improper installation.

Common main sewer line problems


Most homeowners fear sewer line problems because fixing them is expensive and disruptive. These pipes are hard to see and reach and fixing them is a challenge. Knowing what are the most common problems affecting sewer lines can help you be proactive:

  • Clogs

Clogs are quite common and occur easily. They happen if you throw solid items in your toilet, such as feminine care products or diapers. Disposing of waste correctly is the best prevention for clogs.

  • Tree root growth

Avoid planting trees close to your sewer line. They will provide fresh air but in time they can scavenge your pipes. Tree roots cause some of the most expensive repairs, so check the location of sewer lines before planting trees in your yard.

  • Lack of maintenance

You regularly clean your sink drain when it starts to get clogged. But do you do the same for your main sewer line?

The sewer line should ideally have a sewer clean-out – a small portion enabling you to access the pipe. This way, you can eliminate blockages through the clean-out.

  • Leaking joints

This happens when seals between the sewer lines have broken – as a result, water leaks into the ground.

  • Bellied pipe

When a section of the pipe has sunk into the ground, waste will converge in that area. This belly in sewer line may cause standing water and further damage of the sewer pipe.

  • Collapsed pipe

The most dreaded sewer line problem occurs when soil has shifted or the pipe is so cracked that it eventually breaks.

Keep on reading to find out how you can recognize a collapsed sewer line.

Signs of a collapsed sewer line


Sewer line problems can develop unnoticed until the pipe is too damaged to be fixed. A collapsed sewer line will result in costly and inconvenient repairs. Best is to recognize the signs of a damaged sewer line before it collapses:

  • Clogged drains

Every single drain in the house communicates to the main sewer line. This means that a major sewer line problem will affect every drain in your home. You will notice the toilet doesn’t flush properly. The shower doesn’t drain, and the sinks don’t drain either.

The thing to remember is that several drains or all are affected when your sewer line has problems.

On the other hand, symptoms can be intermittent – you might flush now and next morning problems appear again.

Additional signs that the sewer line is in trouble are:

  • Gurgling toilet when the washing machine is running
  • Waste coming back after you flush the toilet
  • Overflowing drains

A plumber can use a specialized snake, possibly with a camera on, and inspect your sewer line. Professionals can solve clogs without having to dig up the entire line.

  • Foul odors

A functional sewer line should be able to move waste away from your home and into the main system.

The presence of foul odor in your drains is a sign of trouble, most possibly a crack in the sewer line. This issue should be dealt with immediately to prevent contact with airborne bacteria.

  • Slow drains

Before clogging, you may notice that water slowly drains off from your sink and other fixtures. If homemade solutions or chemical cleaners don’t work, you should call a plumber.

Be cautious with the use of chemical cleaners, as they can contain harsh substances which cause corrosion.

  • A soaked lawn

Do you know how to tell if your sewer line is leaking? Sewer line leaks will definitely reflect into your lawn. Water escapes from the main pipe and makes its way to the surface, onto your lawn. A soaked lawn with puddles is definitely a sign of a damaged sewer system.

More subtle signs are lush spots in your yard, with green grass while the rest of the lawn is dry. This is because water and organic matter in the sewer line make plants thrive. Get it solved as this is not a recommended irrigation method.

  • Broken concrete slabs

These signs appear due to the ground settling and shifting beneath concrete. A collapsed sewer line can even move the soil supporting the foundation and cause cracks in your home.

How can you repair a collapsed sewer line?


Many homeowners in trouble inquire about collapsed sewer line repair cost. The cost of repair depends on the extent of damage.

All in all, you should understand signs of a collapsed sewer line first.

When the sewer line is collapsed, the only fix is replacing it, hopefully without having to dig too much. In order to replace a collapsed sewer line under house, you will have to complete the following steps:

  • Diagnosing the problem based on the signs presented earlier
  • Assessing the location of the sewer line
  • Deciding whether a plumber is required
  • Digging up to the collapsed line
  • Making sure no appliance or fixture is dumping water while working
  • Removing the damaged sewer line from both ends
  • Fitting the new pipe using the right glue compound
  • Testing the new assembly after the fittings have dried

Bottom Line

A collapsed sewer line under house doesn’t have to be a catastrophic event. If you follow our instructions on how to find signs of a collapsed sewer line, you can reduce disaster that may happen. [4]

Now you know how to tell if sewer line is leaking and ask local plumbers about collapsed sewer line repair cost. If you decide to do the repair yourself, be prepared with a new pipe, cutting tools, a shovel, and patience.