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Discharge Line

A discharge line is usually made of PVC and it directs water from the sump pump away from your home. Here is what you need to know about it.

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Having a flooded basement is never a pleasant surprise. First, you need to make sure that the water level has not risen above the outlets, or you could get electrocuted. Then you need to drain the basement, throw out most of the things you had stored there, and check if anything is salvageable.  

Sometimes the floodwater is contaminated with chemicals or sewage, which is why you need to thoroughly clean the floors and the walls, as well as any items you wish to keep. Removing the carpeting is also a must since the floor underneath won’t be able to dry otherwise.  

Unfortunately, even if you do everything we just mentioned, you could still end up with a serious mold problem. Mold thrives in damp and dark places, so if you don’t notice that your basement has been flooded as soon as it happens, mold will spread all over the place, and its airborne spores will contaminate the air in your entire home. 

So how can you discharge large volumes of water as soon as they enter your basement? With a sump pump, of course. However, while the purpose of the sump pump is to pump out the water from the basement, the discharge line directs it away from your home, so it cannot cause more damage. Here is everything you need to know about the discharge line and possible issues you could come across. 

installing discharge line

What Is a Discharge Line? 

The discharge line is basically a PVC or copper pipe. However, PVC pipes are the most recommended type since they are durable, strong, and do not rust.  

A discharge line is connected to the sump pump and when this device collects water from the flooded basement, the discharge line directs it outside. Usually, this pipe is buried in the ground, so it doesn’t disrupt your landscaping and is protected from the elements. While the whole point of the discharge line is to direct water as far away from the home as possible and prevent it from causing any damage to the foundation, a lot of homeowners dump the floodwater right next to the home’s perimeter. This is never a good idea since the water that has been drained from the basement makes its way back to the basement through the soil and basement walls. This line should always be directed to a nearby stream or a street drain and run downhill so there aren’t any backflows. 

In the winter, when temperatures drop, the discharge line could freeze if not properly installed, which can lead to clogs. This is why contractors usually install the pipe two feet below the frost line. 

Installing the Discharge Pipe 

Installing a discharge line should never be done by anyone else except skilled contractors. The point of this pipe is to drain your basement so the water won’t damage your possessions and if the installation isn’t done by the book, it is possible that the line won’t function as it should. What is even worse, confident that your sump pump will get the job done, you won’t check on your basement as often as you usually would, and you will notice water damage when problems have already escalated. Therefore, it is always better to let the experts handle such things and be at ease knowing that your home is protected.  

When your local contractors come to install the discharge pipe, they will take the following steps: 

  • The contractor will install a sump pump in your basement. 
  • They will ensure that the sump pump is positioned firmly on the ground.  
  • The contractor will connect a three or four-inch PVC pipe to the discharge hole on the sump pump using PVC cement or an adapter.  
  • A vertical check valve will be installed to prevent water from flowing back to the sump pump.  
  • Afterward, the contractor will drill a hole in the wall where the line will exit the basement. 
  • By connecting multiple PVC pipes with PVC cement, they will direct the discharge line towards the chosen dumping spot.  
  • After the pipe has been pushed through the hole, the contractor will seal the opening with silicone caulk, so that moisture or pests cannot enter the basement through the opening. 
  • In the end, a trench will be excavated so that the pipe can be buried underground. 

Possible Issues with Sump Pump Discharge Lines 

When installing the discharge line, contractors should pay attention to the size of the pipes. If they are too narrow, the water won’t leave the basement as fast as it should. In fact, it could come to sump pump backups which will damage this device. 

Another element that should be considered during the installation is the discharge point. This part of the pipe is exposed to dirt and debris, so it can get clogged. In addition, frozen water can clog the exit point. Luckily, with a special anti-freeze attachment, water can escape from a discharge line even if pipes freeze or become blocked. 

Another problem that could happen is that the check valve is not functioning properly. If this happens, you will see the water washing back down into your sump pit. This will result in the increased natural wear and tear of the sump pump, and the device will burn out much earlier than predicted. 

Discharging Water into the Public Sewage System 

Of course, it makes sense to dump all that basement water into the sewer. However, this can contribute to sewers becoming backed up. To reduce the pollution of waterways, discharging water into public sewers became illegal in some parts of the country. 

If you wish to install a sump pump with a discharge line, contact professionals at AFS. We serve homeowners in Tennessee, Alabama, Georgia, and Mississippi, so contact us today to schedule a free inspection and estimate. Your inspector will assess the situation with your basement and recommend suitable waterproofing solutions. 

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