How To Know if You Have a Main Drain Line Clog

How do you know if you have a Main drain Line Clog is something every homeowner should know.  Being able to quickly figure out if you have a sewer line break or clog could save you thousands of dollars and keep your home from becoming damaged. 

Here are the top 6 Ways to Know if You Have a Drain Line Problem.

How To Know if You Have a Main drain Line Clog
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What are the 6 Signs of a Main Drain Line Clog?

There are a few ways to figure out if and where the drain pipe problem is in your yard.  They are the first steps in sewer line leak detection.  How do you determine if there’s a leak in the sewer pipe in your yard?

As a homeowner, knowing how to recognize signs of a Main drain Line Clog can save you thousands of dollars and prevent damage to your home.

Typically, insurance doesn’t cover the cost of a broken drain line, making it crucial for you to be vigilant with your drain pipes. Conducting regular inspections with the best drain camera is a proactive step you can take to keep your sewer pipes in good shape. But how can you know if there is a clog in your drain line?

6 Signs You Have a Main drain Line Clog

  • Soggy Spots in Your Yard
  • Sewer Gas Odor
  • Extra Green Patches on Your Lawn
  • Lawn Has Indents
  • Large Trees with Big Roots
  • Driveway Is Sinking

Soggy Spots in Your Grass or Yard 

Is there a few spots in your yard that never seem to dry out?  Are they soggy and wet year-round, even when its mid-summer? You might have a crack or leak in your pipe right underneath that soggy spot. 

Sewer Gas Odor in and/or Around Your House 

First things first here.  Make sure to check in the P trap inside your drains.  The P trap is built to hold water in it to prevent any sewer line gases from getting back up into your home.  It could be plugged or have some other issue with it, that’s letting the gas vent back into your home.   

What is a P Trap?

p trap
P Trap Under My Bathroom Sink

A P trap is the big main elbow in your drains that you can see when you open up the kitchen or bathroom cupboards under your sink.  The P trap is built that way so that is hold water in it.  

P traps are a building code requirement.  The water in the P trap blocks any gases from coming up from the main drains and getting inside your house.  

Once you see how big of a corner the P trap is, you’ll understand how gunk and debris can gather there.  Do yourself a favor and place a drain catcher in your sink to catch any weird stuff.  This way it won’t find its way into your drains and P trap.

Also, don’t put any food or grease down your drains.

If the P trap is fine, then start looking around for the source of the odor.  Backed up sewage and grey water isn’t going to smell like roses, it will stink.  Once you find the approximate location of the source of the smell, you’ve probably located your leak. 

Extra Green Patches on Your Lawn 

Even if your lawn isn’t soggy, there might still be a leaking pipe underground.  Another telltale sign is when your lawn has patches on it that are super green compared to the rest of your lawn.  The drains underneath might be leaking and the nutrients from the water are feeding your lawn, making it that lush green in random spots. 

Lawn Has Indents 

Similar to a sinkhole, your lawn will sink down a bit if there is a leak underneath it. This is because the water leak will erode the soil underneath your lawn, leaving a hole. The lawn above then sinks down into the hole and causes a small sinkhole.

Large Trees with Big Root Systems Could Mean Roots in Your Pipes 

Be careful when planting trees on your property.  Only plant tree species that are NOT going to develop huge root systems that can mess with your pipes, driveway, foundation, etc.  If the tree was there when you bought the house, you will have to address it or you’ll be constantly fighting with the roots to stop them from damaging your property. 

Your driveway or Other Paves and Bricked area are Sinking 

This is because the water leak underneath is causing a sinkhole, and you are seeing “potholes” in your driveway as the water and soil compress underneath.  That sinkhole is a sign of the location of your leak. 

How can I prevent main line drain clogs?

Regular maintenance, such as tree root removal, drain inspections twice annually, and drain cleaning, can help prevent main line sewer clogs.

How to Know if You Have a Main drain Line Clog?  

If you are a homeowner, it’s important to pay attention to signs that you might have a broken or clogged sewer line.  So, what exactly are the Signs of a Broken Sewer Pipe? Let’s review the ways to tell if the break or main sewer line clog is in your yard OR in your house. 

5 Ways to Tell if You Have a Leaking Sewer Pipe or Drain in Your Basement or House   

However, a clog or break in your main drain line can also occur inside your house or basement. Here are five ways to tell if you have a leaking sewer pipe or drain in your home:

  1. Mold in your house
  2. Slow drains (with gurgling sounds)
  3. Cracks in your foundation, sinkholes or settling of foundation
  4. Rats, Mice and Other Pests
  5. Backups in your plumbing fixtures

Main drain Line Clog and Mold in Your House 

No one wants mold in their home, its so unhealthy. If you’ve never had a mold problem and suddenly, you start finding mold in your bathroom, basement, closets, or even the corners of your rooms, you might have leaking drain pipes.

Those leaking pipes are building up humidity under your home. The moisture is then getting into your home and causing mold to grow.

Slow Drains 

This one is pretty easy to see. If your drains and toilet start draining slower and slower, then you could have a main sewer line clog. There are many reasons why your drains would be clogged. Maybe something was flushed, there is a build up of grease and gunk, or there could be roots in your pipes.

Get a drain line inspection sooner instead of later to keep a small problem from turning into a huge emergency.

Cracks in your foundation, sinkholes or “settling” of foundation 

Long term leaks cause sinkholes and depressions in the soil under your home. This can cause your house to “settle” unevenly resulting in the walls cracking under the pressure of their own weight.

Also, if you notice your doors never fit quite right and are shifting slowly over time, your house might be “settling” and shifting. Get those drain pipes checked as part of your problem solving.

Main drain Line Clog & Rats, Mice and other Pests 

Rodents can squeeze themselves through small cracks in your pipes and make their way into your home through the toilet and drains. If you start noticing a rodent problem and you’ve tried everything to stop it, check your drains.

Same goes for insects. They can get into cracks in your pipes and make their way into your home. DISGUSTING!

Backups into your Plumbing

If you have your kitchen sink, tubs, showers or bathroom sinks backing up when you drain water from other sinks etc. in your home, this could indicate that the water is unable to drain down the main line and that the main line may be clogged.

Can a main line drain clog be fixed without digging up my yard?

Yes, there are methods such as hydro jetting and trenchless drain repair that can fix a main line drain clog without digging up your yard.

Can a main line drain clog cause health problems?

Yes, a main line drain clog can create unsanitary conditions that can lead to health problems, such as mold growth and exposure to harmful bacteria.

What Happens if a drain Line Breaks?   

First let’s talk about why it’s so important to make sure that you keep your sewer pipes in tip top shape and inspect them regularly with the best drain camera.  Every homeowner needs to be vigilant with their drain pipes, because most of the time, a broken drain line is not covered by insurance. 

If a drain line breaks, you won’t be able to use anything that requires water in your home, including the toilets and bathtubs. It could cause back up into your home, costing thousands of dollars in repairs.

How long does it take to clear a main line drain clog?

The time it takes to clear a main line drain clog can vary depending on the severity of the clog and the method used to clear it. If we have to hazard a guess, at least 2 hours because you have to inspect the pipes first with a drain camera to diagnose the problem.

How much does it cost to repair a main line drain clog?

The cost of repairing a main line drain clog can vary depending on the severity of the issue, but it can range from a few hundred to several thousand dollars. This is why it’s important to inspect your drains twice per year and catch small problems before they becomes extremely expensive issues.


A main drain line clog can cause significant damage to your home and can be a major inconvenience. However, by knowing the signs of a clog and taking preventative measures, you can avoid costly repairs and keep your plumbing system running smoothly.

Remember to pay attention to any unusual sounds or smells coming from your drains and to avoid flushing inappropriate items down the toilet. Regular maintenance, such as having your pipes cleaned and inspected by a professional, can also help to prevent clogs from forming in the first place.

If you suspect that you have a main drain line clog, it’s important to act quickly and seek professional help. Don’t hesitate to call a licensed plumber to diagnose and fix the issue before it causes further damage to your home.

By staying informed and taking proactive measures, you can avoid the stress and expense of dealing with a main sewer line clog. Keep your plumbing system in top shape and enjoy peace of mind knowing that your home is protected from potential plumbing disasters.


Should I try to fix a main line drain clog myself?

It’s not recommended to try to fix a main line drain clog yourself, as it can be dangerous and cause further damage to your plumbing. It’s best to contact a professional plumber for assistance.