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A sewer line backup or leak can be frustrating to deal with as a homeowner. Along with the unpleasant smell and messy cleanup of a compromised sewer pipe, it can be difficult to pinpoint the root cause of your sewage problem.
To help prevent sewer line damage or mitigate an issue when it arises, it’s important to know how to spot the main causes of sewer line damage. Here are the common causes of a damaged sewer line, signs to look for, and how you can repair or replace your sewer system.
Causes of Sewer Line Damage
From clogged pipes to normal wear and tear, here are a few causes of sewer line damage.
One of the most common causes of sewer line damage is tree roots. A tree’s roots follow sources of water as they grow. Since sewer lines carry liquid waste, roots are naturally attracted to the source—particularly when there is already a small leak in the piping.
Once in contact with a sewer pipe, tree roots begin to wrap around and break into pipes, clogging, weakening, and even breaking the structure. Clay sewer pipes, typically found in older homes, are the most susceptible to damage from tree roots.
Although pipes made of steel and cast iron are galvanized to prevent rusting, these pipes are at a high risk of corroding due to calcium and magnesium build-up from regular wear and tear. If corrosion is left untreated, it can leave the pipe susceptible to leaks and cracks.
Clogged Pipes Due to Debris and Foreign Objects
Your home’s sewage lines are only equipped to handle human waste and toilet paper. Avoid flushing trash like wrappers and paper towels, as they’re unable to properly disintegrate and can cause blockages that drain cleaning agents can’t fix. In the kitchen, cooking oil and grease can also clog pipes if they’re poured into the sink. Pour these liquids into a container, let them cool, and then dispose of them in a trash can.
Read More: How to Clear a Clogged Drain
During extreme temperature and cold weather, frozen pipes can bust as a result of the expanding ice. However, it’s not just cold weather that can cause pipes to rupture—though unlikely, extreme heat can burst pipes, too.
Depending on the type of repair needed, this cost can range from $50 - $500 per foot of pipe.Get Estimates
Costs for a full line replacement usually range from $3,000 to $6,000.Get Estimates
The most common plumbing jobs usually cost between $150 and $500.Get Estimates
Signs of Sewer Line Damage
To prevent further damage, it’s important to know the signs of a damaged sewer system so that you can take immediate action and contact an experienced service technician.
Flooded or Foul-Smelling Yard
A yard that’s flooded can be a sign of a broken sewer pipe. Sewer lines can be buried anywhere between a couple of feet to six feet below the ground, with colder climates calling for deeper pipes. For sewer lines close to the surface, a broken pipe can quickly begin to pool water which seeps through the grass and becomes visible on the surface. You may be able to smell the sewage before it surfaces, as sewage gas can seep through your yard’s soil.
While some blockages are caused by a pipe leading directly from a faucet or shower, you can detect a blockage in the main sewage line if multiple draining areas in the home are clogging. Toilets can warn of severe blockages if strange gurgling sounds occur when air gets pushed back up the line.
Water Damage in the Home
Water damage can occur if a drain line leaks or breaks in the home. One of the first signs is mold spreading on the floors or walls. This could point to a broken sewer line within the home, in which case you should call a plumbing service immediately.
Sewer Line Repair and Replacement
If your sewer line springs a leak or breaks and needs to be repaired, you have two options: Dig a trench around the sewer pipe or use trenchless sewer line repairs. A trenchless sewer repair is time and cost-effective while requiring little to no digging. To start the process, technicians use a video camera to enter into the sewer line and recommend repairs. Then, one of two plumbing repairs is usually recommended:
1. Pipe lining—If the damage to your sewage pipe is minimal, pipe lining can be used to insert an inflatable tube covered in epoxy into your sewer line. From there, the tube is inflated, pressing against the existing line. While it’s up against the existing sewage line, the epoxy cures and hardens, repairing the leak. The inflatable tube can then be removed and the sewer line repaired.
2. Pipe bursting—When a sewer line is too damaged to use the pipe lining technique, a more invasive trenchless repair can be performed. Technicians feed a cone-shaped bit through your existing line and destroy the pipe while immediately replacing it with a new one. This process is more expensive and less time-effective, but it doesn’t require extensive excavation.
If your pipes are damaged beyond repair, you may have to resort to traditional sewer line replacement methods. This is an extremely invasive and costly method that requires technicians to dig up your yard to reveal the damaged or broken lines. However, excavation is necessary if your home’s sewage system has extensive damage.
How to Protect Your Sewer Lines
Although not all sewer line damage is preventable, here are three steps you can take to care for your sewage system:
1. Receive sewer line inspections once a year—To confirm that your sewage system is in good working condition, hire a professional to conduct an inspection at least once a year. Some plumbing companies offer a camera inspection so that the inside of your sewer pipe can be checked for corrosion or blockages.
2. Remove trees that are damaging the sewer line—Although a root invasion in your sewer line is often caused by an already-existing crack or leak in the pipe, we still recommend removing the tree from the area after repairing or replacing the pipe to ensure the problem doesn’t arise again in the future.
3. Use your sewage system properly—Remember to only dispose of human waste and toilet paper in the sewer lines; any other materials that enter the system can cause blockages.
Sewer Line Repair FAQ
How long will a sewer line last?
The life of your sewer line depends on your pipe’s material. Cast iron pipes last between 75–100 years, clay and cement pipes can last up to 100 years, orangeburg pipes last around 50 years, and PVC pipes can last over 100 years.
Does homeowners insurance cover sewer line damage?
Unless your sewer line was damaged by another party, it’s unlikely that homeowner’s insurance will cover the damages. Fortunately, many home warranty companies give you the ability to protect your sewer lines through septic system coverage.
How long does trenchless sewer line repair last?
Trenchless sewer repairs like pipe bursting and pipe lining are minimally invasive sewer pipe repairs that are known for their longevity. The amount of time the repair lasts depends on your pipe’s material and method used; however, most trenchless sewer line repairs last up to 50 years.
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