How to Clear a Main Line Blockage

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Do you have problems with water going places where it should not be going? Overflowing the kitchen floors or bathroom tiles?

If you do, you probably have trouble with the sewage system. Its consequences can be fatal for your time and especially for your wallet. Plumbing problems can be tricky and if they go further than they are supposed to, you are going to need help from the professionals.

That is something you can prevent. Here, you can read some useful and effective information about cleaning your clogged drains. 

how to clear a main line blockage

How do you know when your main sewer drain is clogged?

You will start to hear some strange noises, gurgling sounds from the sink for example.

You will start to see awkward things. Things like deluge, bursting out for no reason. Water running back from the toilet when you turn on the washing machine and so on. That is the finishing phase of clogging.

But there are signs that can tell you when something is not right:

When your pipes are running slower than usual and you cannot fix or clean them. You are trying your best but with no success. Then you know that you have a problem with the main drain line.

If you flush your toilet and the water level in your tub starts to rise, then that is not good either.

Toilets pipeline is bigger than the rest of the house's fixtures, it also has the most direct route to the sewer. That means if you do not have problems with the toilet but you have with the shower, sink or tub, then you are fine.

The complications often occur when you run your washing machine and the sink or toilet start to overflow.


Bottom line, when the sewage main line is clogged, the wastewater has nowhere to go. And it must go somewhere.

So, if it cannot go forward It must go backward and the victims are all of your house water fixtures. Do not get scared, you are not a part of some horror movie. These problems are not so serious in the beginning and you can fix them easily.

A small complication from the main sewer line can spread out through entire household. That can be, potentially, a serious problem and you certainly do not want it.

How to clear a main line blockage

First of all, you will need to release the water pressure. How do you do that? It is very simple. You have to turn off the water at the main supply.

Then, inspect your backyard or basement and look for a cleanout sewer pipe. That should be easy to find. It is a white, short pipe, about three or four inches in diameter and on top of it there is a cap.

Once you have spotted it remove the cap. You should be able to remove it with your hands only if it is a screw-on one. If it is not then you can use the wrench to loosen up and then remove it.

The reason why you are doing this is to let the water out. You are releasing the pressure in the sewer line and the backed up water from your home will drain out.

There are few techniques that you can use for resolving these problems:

  • Chemical drain cleaning
  • Mechanical drain cleaning

Chemical Drain Cleaning

Chemical drain cleaning is used for tree roots embedded in your sewer pipes. They can be very tricky to clean. This method is using chemicals for destroying its opponents. So, read carefully.

Some of the professionals recommend copper sulfate. Its strong characteristics can dissolve stubborn tree roots stuck in your pipes. The procedure is quite simple. Just pour the compound into your toilet and flush.

It can do the job but you will need to repeat the action a few times. You must repeat the application several times because the compound will not stick to the pipes.

WARNING, WARNING! Copper sulfate is banned in some communities. Also, if you have a septic system you better not use this particular item.

If this thing will not work, there is something you could replace it with.

You can try flushing root-killing foam down your toilet. The foam contains herbicides that can destroy the roots within a few hours.

Because of its ability to stick to the pipes, you would not have to repeat the process again. Do not be impatient, it will take up to several months before it is all flushed for good.

See here for the best drain cleaner for main line.

Mechanical Drain Cleaning

Mechanical drain cleaning is a job where you have to take everything in your hands. Literally. Even that you cannot do on your own. But with the help of some useful tools, the job could be easily done. You have a broad specter of tools at your disposal.

Some of the most effective ones are auger and high-pressure water jets. The auger, commonly known as the drain snake, is a flexible cable. It is power assisted. 

electric snake

How does it work? There are different kinds of these tools and you better read the manuals before using them if you want better results. However, the foundation is pretty much the same.

You have to put the auger cable into your drain pipe until you hit the desired place. Be cautious and gentle. When you have reached the clog you will know it. The cable will start to move slower because it has reached the beginning of the problem. Then the machine will do the rest.

Allow the auger to get through the obstacle and keep the machine on, do not turn it off immediately. The determination will pay off.

You need to keep the auger on because there can be small pockets that can cause new problems. Just wait until it is all rinsed out and then pull out the auger.

For your next move, you will need a hose. Spray the hose down your pipe drain at maximum power. The full blast of your hose will clear the drain from any lingering parts.

Slowly pull out the plumbing snake while rinsing. The goal here is to clear out the auger and all that has left. Your job here is pretty much all done. Just tighten the cap back on and sit back and relax.


You can also try a different thing to clean your drains. High-pressure jet is one the most effective and dependable techniques.

The high-pressure water jet is a method where you can clean your pipes using the power of water stream. It can push through all the things that are blocking your drains. Using just the power of water, you can control the situation.

This means that you cannot damage your pipes because you are controlling the amount of pressure that is used. All of the grease and debris glued in your pipes would be efficiently eradicated. The process is quite simple.

Using flexible hoses and pumps will undoubtedly remove desired things. The hose with a special nozzle is made for penetrating even the hardest shapes of clogging. This method is, without a doubt, one of the mightiest and you will not regret it for sure.

Propositions for preventing drain problems 

We explained to you some of the ways on how to respond to these problems when it is already too late. Now, we can share with you some of the tips to prevent these happenings.

  • Do not empty into your sink any materials that can solidify.
  • Do not flush things that can be stuck in your toilet. Things like heavy paper or cotton buds, for example.
  • If you have a cesspool, have it checked once in a couple of years (every two or three).
  • Use a drain maintenance system. It is designed to reduce growth problems in your pipes.

Conclusion: How to Clear a Main Line Blockage

In the light of everything we said above, these are some of the simplest solutions to your main line blockage.

Hopefully, this article made some things easier for you!