A Complete Guide to Drain Lines for Water Softener Units

A Complete Guide to Drain Lines for Water Softener Units

It’s easy to overlook the importance of a drainage line when you are installing a water softener. But without this element, minerals will build up within the system. This can cause the water softener to stop working, leading to hard water flowing into your pipes and plumbing system.

The good news is that it’s easy to install a drain line to ensure that your unit continues to operate properly. There are plenty of drain locations to explore, depending on where your unit will be located. Keep reading to learn more about the importance of drain lines and how you can install them.

Related articles:
Ultimate Guide to Water Softeners: Everything You Need to Know
Where To Discharge Water Softener Backwash – The Ultimate Guide

Why Your Water Softener Needs a Drain Line

To understand why your water softener requires a drain line, we need to know a little about how the device removes calcium and magnesium particles to create soft water. Usually, the steps of this process look like this:

  1. Water enters the system and passes through the resin bed
  2. The resin absorbs the calcium and magnesium
  3. Soft water emerges from the resin and comes out of the tap

The problem is that the resin beads will start to get full of minerals over time. As a result, they will need to go through a process of regeneration. In this case, the resin system will be backwashed, and the minerals will be flushed down the drain line. It will also get rid of any dirt and any other crud that has accumulated within your system. After this, the resin will be able to continue to absorb calcium and magnesium. 

If the mineral-heavy water doesn’t get flushed out of the system, it can create problems. Here are some of the signs that there is a problem with your drainage line:

  • No longer be able to generate soft water
  • The water is colored
  • Sometimes, the water might have a poorer taste
  • Lack of water flow

These are just the initial symptoms. If you don’t take action, the problem could become significantly worse over time. The minerals and dirt will sit within your water softener. This can lead to damage to the resin. If you want to get this fixed, you will be looking at a large repair bill.

Even worse, the regeneration involved flushing a large amount of water through the system. Without any drainage, the water softener could overflow. This can create a huge mess and expose your home to water damage and mold.

The good news is that it’s easy to protect yourself from these issues. However, you will need to be a little careful about how you install the drainage line. There are often building or plumbing codes that will dictate where the discharge needs to go.

Related articles:
Can a Water Softener Be Installed in the Attic?
Can a Water Softener Be Installed in the Garage?

Drain Line Options for Basement Units

Sometimes, you might have a water softener unit located in the basement. In this case you can consider the following options for drain lines.

Sump Pit

water softener drain line - sump
A sump pit can be used as a discharge location for a water softener in a basement

The sump pit is a hole in the floor of the basement which is designed to catch the water seepage from weeping tiles. Once the sump pit starts to fill with water, the pump will be activated and it will be drained outdoors.

You can take advantage of this by placing your drain line at the top of the sump pit, so the water is flowing into the pit. There is just one caveat to keep in mind. You will need to make sure that the sump pump is ready to cope with the higher volume of water. Furthermore, you will need to make sure that you use an air gap over the drainage line. This stops particles from getting into the sump pit.

Check out this video on how to install a water softener drain line into your sanitary sewer pipe.

Floor Drain

Water softener drain line - floor drain
Many water softeners discharge directly to floor drains located adjacent to the unit.

The next option to consider is a floor drain. This is one of the most common options. In this case, you will need to run the drain line across the room, positioning it above the floor drain. Here are a few pros and cons to consider before taking this approach:

  • Floor drains are in the middle of the room. This means that the drain line can present a potential trip hazard. You can avoid this by sticking it to the floor with duct tape.
  • Will require an air gap. This stops contaminants from blocking up the floor drain.
  • Lack of water pressure. Some floor drains will require some pressure, to force the water up the drainpipe. Most of the time, this won’t be a problem when using a water softener, though it’s best to double-check.

If you don’t want to run the drain line to the floor drain, there might be another option you can explore. Sometimes, there will be a sink in the basement. In this case, you can simply use duct tape to attach the water softener hose to the side of the sink.

Sewage Ejector Pipe

 A third option to consider is to attach the drainage lines to a sewage ejector pipe. This is often used as an alternative to using the sump pit. However, in this case, you will be connecting the line to a vent, which leads into the sewage system.

If you are taking this approach, you will need to pair the drain line with a water pump. This ensures that there is enough water pressure to open the vent. Because of the corrosive nature of drain line output, you will need to choose a stainless steel or plastic pump.

Waste Stack Pipe

Finally, you might want to consider adding the drain line directly to the waste stack pipe. This approach can be a little technical, with these elements required:

  • Air gap. This will stop the debris from contaminating your water lines.
  • P-Trap. This is critical. It will stop sewage wastewater and unpleasant gases from entering your house.

Plus, you will need to create an airtight gap to stop water from spilling into your house. Because of this, it’s often best to ask a professional plumber to do this work for you.

Drain Line Options For Outside Units

If your water softener is located, there are a range of drain line options you can explore. Here are some of the most popular choices.

Septic System Drain Field

Setting up a septic drain field just to deal with water softener drainage is not the ideal system. There are more economical options to explore, as we’ll discuss. But if you already have one, you might want to consider using it.

In this case, the septic system will use a drain field to disperse wastewater across a larger area, minimizing environmental damage. This is especially beneficial with water softener drainage, as the high salt content can damage some plants.

But before you take this approach, there are a few things to consider:

  • Size of the septic tank. This might not be suitable for a smaller tank. There isn’t enough space for the salt to settle on the bottom of the tank, which can lead to clogs within the septic system. Plus, too much water can lead to the system becoming overloaded, causing soggy spots.
  • Rules in your local area. Some local councils have banned the use of this practice.
  • Consider the warranty of the system. Sometimes, your septic system will be voided if you add water softener run-off, because of the high brine content.

French Drain

A French drain is relatively easy to install. In this case, you will use a long piece of drainage pipe with small holes. Place this into a narrow drain, with pebbles on either side of the pipe.

 The idea is that you will be spreading the backwash across a wider area. This is designed to limit environmental damage. The pebbles ensure that the water can be absorbed into the soil at a natural pace.

Dry Well

Finally, you might want to consider using a dry well. This can be used for more than just water softener units. You can also use this as a store for the water from downspouts and greywater from washing machines. This is also easy to install, as you should be able to construct it within a day or two.

The idea is that you will dig a large hole in your backyard, above the water table. The outside of the hole can be lined with landscape fabric and rocks. Then, the greywater will flow into the well. Over time, it will seep into the surrounding soil. This will occur at a natural pace, preventing the surrounding areas from getting oversaturated. It will also help to limit the amount of sodium that is entering the environment.

Tips To Find the Right Drain Line Option For You

As we’ve seen, there are plenty of drainage options for you to explore. Here are some tips to help you find the right one for you:

  • Local regulations. There will often be rules from your local council that govern how you can drain the backwash. For example, if you rely on groundwater, you might not be allowed to drain water softener backwash directly into the soil.
  • What is available. You should try to use features that you already have installed within your home. For example, you might not have a sump pit but you can access the sewage ejector pipe.
  • Consulting with a plumber. It might be a good idea to use a plumber to help you install the water softener. In this case, they will be able to help you set up the drain line. Even if you install the unit yourself, you can still contact a plumber to install the line for you. While this will be an additional expense, it will be cheaper than the clean-up from a line that wasn’t installed properly. 

How To Install a Water Softener Drain Line

Hopefully, you have a better idea of the type of drainage option you are going to use. Now it’s time to connect the drain lines to the water softener. Here are some of the steps to follow during this process:

  1. Attach the drainage hoses to the water softener. There are two lines to attach. First, you will need to attach it to the control valve. This is the main line. Secondly, you will need to attach a line to the brine tank, this will serve as the overflow line, in case of a problem with the main line.
  2. Take the lines to the drain point. Most of the time, you will have a long enough drainage line. Though you might need to use a connector to extend the lines.
  3. Add an air gap. This will usually be a requirement, stopping contaminants from entering the water supply.
  4. Connect to the drainage system. Finally, you can connect this to whatever drainage option you prefer.
  5. Run the system. Use a manual regeneration to test that the drain lines work. Make sure that the water is flowing smoothly and that there aren’t any leaks.

As always, it’s best to refer to your owner’s manual. This will often contain detailed instructions on how to attach the drainage lines correctly, according to the unique specifications of your device.

Clearing Blockages in a Drain Line

Sometimes, you might have a blockage in your drain line. This can prove to be very dangerous. If left unchecked, it can cause your machine to overflow, leading to substantial water damage. Or the dirt and minerals can accumulate within the resin, which can lower the machine’s effectiveness and lead to a huge repair bill.

The good news is that there is a simple way of ensuring that this doesn’t happen. You just need to pay attention to issues with your water softener and investigate a blockage if you suspect a problem. Here are the steps to clear the blockage:

  1. Turn off the water softener, or direct drainage to the bypass line
  2. Remove the drain line and inspect for clogs
  3. If you see one, run the line under the water and use your fingers to gently massage the clog out of the pipe
  4. Re-install the drainage line
  5. Run a manual regeneration to check that the water is draining properly

Final Thoughts

For your water softener to work correctly, you will need to have a drainage line. The good news is that installing this line is a relatively straightforward task. There are plenty of drainage options to explore, so you should be able to find one that is convenient for you.

Boch Richard

Richard Boch is a chemical engineer responsible for designing water filtration systems for industrial and residential customers. He has more than 20 years of experience with ion exchange, activated carbon, and reverse osmosis. Richard's expertise has made him a go-to source for municipalities and businesses looking to improve their water quality. When he's not working, Richard enjoys spending time with his wife and two young children.

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