How To Tell If A Sewer Pipe Is Leaking (Here Are 6 Telltale Signs)

Upgraded Home Team
by Upgraded Home Team

Modern plumbing is a wonderful convenience that allows us to live safe and sanitary lives. Many people rely on municipal sewer systems to help remove wastewater cleanly and efficiently from your home. Sewage usually safely travels through the sewer pipe connecting your home to the municipal waste plant. However, sometimes a leak can occur within your sewer pipe, leading to major plumbing complications.

When your sewer pipe is leaking, you compromise your entire plumbing system. Signs that your line may be leaking can include a strong sewer odor in your home, unusually lush grass in your yard, or mold and mildew forming in the basement. Confirming a sewer leak is possible with a professional plumber performing specialized leak tests.

Sewer pipes can become damaged from several outside forces beyond our control, such as expanding tree roots and extreme temperatures. Watching for the warning signs of a leaking sewer pipe is the first step to repairing and treating your broken pipes. Additional testing and repairs completed by a licensed plumber will rectify the situation in the most efficient and cost-effective method possible.

Do You Need Sewer Cleaning Services?

Get free, zero-commitment quotes from pro contractors near you.

What Happens When There is Sewage Leaking In Your Home?

A leaking sewer pipe can spell disaster and can be caused by a broken or a burst pipe or compromised plumbing joint. If left untreated, the leaking sewer pipe may impact your entire drain and plumbing system. Leaks within the sewer pipe can cause sagging and further separations throughout your system.

Further, the leaking sewage will start to pool in your yard, creating an unsanitary and unsafe condition. Leaking sewer pipes should always be located and repaired to meet municipal code to stay safe and protect the integrity of your home.

What Are Signs My Sewer Pipe is Leaking?

The first step to repairing your sewer pipe is to determine that a leak is present. There are often some warning signs homeowners will notice that can suggest a sewer pipe has ruptured. Look for signs that include:

  • Soft or mushy areas of the yard that are extremely moisture rich
  • New green and thick vegetation growing in one part of the yard
  • Strong  sewer gas smell in the basement
  • A wet or moldy basement
  • New foundation cracks
  • Clogged or slow drains

If you start to notice any of the above signs that other plumbing occurrences cannot easily explain in your home, it may indicate that you have a leaking sewer pipe. Be sure to call a professional plumber to come out and perform additional testing to determine if and where your sewer pipe is leaking.

How Can You Test For A Leaking Sewer Pipe?

If you notice some common signs that your sewer pipe is leaking, additional testing may be required to confirm a leak. Finding the type of leak, severity, and location can help a licensed plumber repair the leak in a timely and cost-effective manner. Some of the more common types of tests to detect a leaking sewer pipe include:

  • Hydrostatic Pressure Test – For this test, a small, particular ball is placed within the sewer line. Usually, the ball is inserted into the sewer line by removing the toilet and inserting the ball through the drain opening. The ball is inflated to block the pipe completely. When water is added to the drain line from the faucet, the pipe will fill under the ground level. A contractor will watch to see what happens to the water level in the toilet line. If the water line steadily goes down, it may suggest that a leak in the sewer line is present. A leak can be confirmed with a video inspection camera to conclude the inflated ball is blocking the space and that there is a leak further down the sewer line.
  • Static Leak Isolation Test – During this type of test, a plumber will first begin with a hydrostatic pressure test followed by a camera inspection to find the leak’s location. The only difference is that the plumber will move through the plumbing system in your home or building to isolate the sewer line’s location where the leak occurs. Be aware that during this test, the plumber may have to remove multiple toilets from their base to install multiple inflated balls to test the water level at various points.

What Causes Sewer Lines to Leak?

Sewer leaks can be complicated to repair and costly to replace. Unfortunately, several outside factors can cause your sewer pipes to leak. Some common causes for a sewer leak include:

  • Trees – Having big and beautiful trees around our home is lovely, but tree roots can damage sewer lines. Leaking sewer pipes are commonly caused by tree roots that seek out water sources as they grow. Because the sewer lines carry water and waste through the pipes, a tree root is attracted to the pipes. Tree roots can wrap around a pipe, causing it to break.
  • Clogged Pipes – Having debris float through your pipes can lead to clogs that damage the sewer lines and cause leaks. A sewer line is only meant to handle human waste so that foreign objects can lead to clogs and damage. Having a clog in your pipe can cause blockages that normal cleaning agents can’t fix.
  • Temperatures – When water freezes, it expands. If sewer water is left in your sewer pipe during extremely cold temperatures, it can freeze, grow, and burst the sewer line. On rare occasions, extreme heat can also cause sewer lines to burst too.
  • Corrosion – Many modern plumbing systems are made with durable and long-lasting PVC pipes, but older homes still use cast iron or clay pipes. Cast iron can prevent rusting, but these pipes can still corrode when magnesium and calcium, commonly found in the water, are left to build up over time. When the corrosion is left untreated, the pipes can crack and start to leak.

How Can You Fix a Leaking Sewer Pipe?

Fixing a leaking sewer pipe can be simple or complicated, depending on the size of the leak and the amount of damage done. If your plumber finds a leaking sewer pipe, you may have several options to fix the leak, including:

  • Pipe Lining – Sometimes, this method is called cured-in-place-pipe lining. This method is only minimally invasive and is considered a trenchless technique often used for fixing a damaged sewer pipe. This method creates a brand new pipe that fits inside the old pipe. The technique uses a felt liner that is dipped in epoxy and then inserted into place. The new line is left to sit for a couple of hours, and the pipe will be functional again with the new, thinner pipe liner in place.
  • Spray Lining – A polymer resin is often used to spray the area within a leaky pipe. This repair is common when the damage is extremely minor, and the leaking sewer is minimal. The spray liner is installed, left to dry, and leaves a minimal invasive footprint on your home and plumbing system.
  • Burst Pipe – Unfortunately, sometimes a burst pipe can spell a big repair, especially if your structural integrity is in question. A leaking pipe that has collapsed on itself must be expanded to allow one of the above treatment methods to work. The pipe is expanded, and a brand new solid pipe is inserted into the collapsed pipe to create a structurally sound and stable plumbing connection.

What Happens If My Sewer Pipe Is Leaking Underground?

It is quite an easy fix if you can visibly see the area where your sewer pipe is leaking, but what happens when the leak occurs underground? Unfortunately, a leaky sewer pipe underground is a much more extensive repair. Underground leaks can be challenging to diagnose and locate and often requires the help of a licensed plumber. Fixing an underground sewage leak is well beyond the skill set of even the handiest homeowners.

To fix a leak underground, sometimes heavy digging tools are required to reach the pipe. If the pipe is under your basement slab, the concrete may have to be broken with a jackhammer. Further, digging into your slab and foundation to track a leaky sewer pipe may require additional permitting and structural support to fix the issue.

Do You Need Sewer Cleaning Services?

Get free, zero-commitment quotes from pro contractors near you.


Related Questions

How long does PVC pipe last?

PVC is a commonly used product in plumbing applications because it has several benefits. One of the best benefits of PVC is its incredibly long lifespan. Expect PVC pipe to last about 100 years. Compared to its alternatives, this is nearly double what other plumbing materials can offer. Clay pipes will usually only last about 50 or 60 years, while cast iron pipes may only last 30 to 50 years.


Which pipe is best for the sewer line?

When choosing which pipe is the best for a sewer line, PVC wins by a landslide. For the past 40 years, PVC has been the trusted material of plumbers around the world. This material is lightweight, extremely long-lasting, relatively flexible, and is affordable. Many homeowners decide to replace existing cast iron or clay pipes with PVC because of the many associated benefits. There are several varieties of PVC available, including unlimited lengths and thicknesses.

Related Articles

Upgraded Home Team
Upgraded Home Team

We are a team of passionate homeowners, home improvement pros, and DIY enthusiasts who enjoy sharing home improvement, housekeeping, decorating, and more with other homeowners! Whether you're looking for a step-by-step guide on fixing an appliance or the cost of installing a fence, we've here to help.

More by Upgraded Home Team

Next