Do All Water Softeners Need a Drain? (+Draining Options)

Naturally, we want all of our appliances to work smoothly. But how do you know if you are doing all that you can to ensure this? When you install an appliance like a water softener, you might assume that all safety measures have been taken, but are you sure?

There is so much to know about our different appliances, how they work, and what preventative measures to take. Many of us may not be aware that attaching a water softener to a drain should be a consideration.

In order for a water softener to function correctly and with minimal maintenance, it needs a drain. Most water softeners utilize floor drains that lead to sewer lines. Other options are laundry trays, utility sinks, and plumbing trap outlets.

Here are the reasons why a water softener drain is important, what can happen if one isn’t installed, and the different draining options available.

What is a Water Softener Drain?

Before you decide whether your water softener needs a drain, it’s important to understand exactly what it is, and what it does for a water softener. These appliances have several working components, and each of them are important to the proper functioning of our systems. For conventional water softeners, a drain is one of these components.

In conventional water softeners, heavy minerals are removed from the water by a process known as ion exchange. During this process, the calcium and magnesium ions present in hard water are exchanged for sodium or potassium ions in a resin medium. In order for this exchange to take place, water is passed over the resin.

When the resin becomes saturated with calcium and magnesium, a flushing process happens, known as regeneration. During regeneration, a brine is flushed through the resin, replenishing the sodium or potassium and removing the calcium or magnesium. This brine now has to go somewhere, and certainly not into the water supply, as that would defeat the purpose!

This is where the drain comes in. There are different types of drains, and a variety of places where the brine is directed, but they all have the same purpose-to remove the brine from the water softener without contaminating the home’s water supply with the very elements we want to remove from hard water.

Consequences of Not Having a Water Softener Drain

As we mentioned before, the spent brine has to go somewhere. All liquid finds an outlet sooner or later, as we all know. 

If the brine is unable to escape through a drain, it will inevitably mix with the softened water and reverse the work done by the water softener. These heavy minerals will circulate through the house, causing the very problems that water softeners are intended to prevent.

These hard minerals will inevitably build up in your water softener, as well. This mineral buildup will clog lines and create limescale that degrades important working components, leading to expensive repairs and tedious cleanup jobs. 

The retained minerals will also collect on resin, forming a hard scale that renders them useless. At this point, they will need to be replaced, adding to the expenses we already discussed.

Water Softener Drain Options

Now that we understand what a water softener drain does, and the possible consequences of not installing this feature, we can figure out which type of drain is best for our home. Deciding which option is best comes down to the capabilities or limitations of your home, the discharge zone you will use, and local regulations. We will cover all of this, starting with the different types of drains.

Laundry Tray or Utility Sink

Laundry trays and utility sinks are commonly found in homes, and have several uses. Laundry trays can catch water leaking from washing machines, preventing costly and damaging floods caused by malfunctioning washing machines. Utility sinks can be used for hand washing household items that can’t go into machines.

When a laundry tray or utility sink is used to drain a water softener, the drain pipe from the water softener channels the spent brine into either of these receptacles. The laundry tray or utility sink then drains into the sewer or septic system, relieving your water supply of the brine.

Laundry Tray

This is a very easy drain method to install, as it simply requires a pipe that runs from your water softener to the receiving laundry tray or utility sink. Of course, there will have to be a drain pipe connecting your receptacle to the sewer or septic system. If there isn’t already one installed where you need it, you may need to consult a professional to make this work is done properly.

Floor drain

This is the most common type of water softener drain. The reason for this is that it is very simple and requires very little maintenance. With this design, a pipe runs between the water softener and a drain in the floor. This way, the water softener is relieved of the spent brine, and it is drained directly into the sewer or septic system. 

Floor drain

Most modern homes already have a floor drain installed, so you just need to connect the drain pipe attached to the water softener. If your home does not have a floor drain installed, this job is best completed by a professional, as it can be complex and require expensive equipment.

Plumbing Trap Outlet

This method is used when there is a need for a direct drain line between the water softener and the discharge zone for your wastewater. In the event that you do not have a floor drain, or a drain that can attach to a laundry tray or utility sink, this may be your only option. Sometimes, a floor drain simply can’t be installed for a variety of reasons.

Plumbing Trap Outlet

With a plumbing trap outlet, there are a variety of discharge zones you can use for your spent brine. It can go into your sewer or septic system, into the ground, or into a dry well. Before you decide on an alternative to your sewer or septic system, be sure to check local regulations. In many areas, law requires this type of drainage to go into the sewer or septic system.

Discharge Zones For Your Water Softener

Now that you know what kind of drains you can use for your water softener, you might be wondering where the drainage goes. Here are the most common discharge zones utilized by drains.

Sewer Line

This is the most commonly used discharge zone used for water softeners. Floor drains, laundry traps, utility sinks, and sometimes plumbing trap outlets direct the spent brine into the sewer line. It usually involves a simple connection to a drain pipe in your home, which flows out to the sewage system. 

If you are not sure if there is a sewage line you can drain your water softener into, it is best to consult a professional plumber. They can locate a line, and even install one if needed. It is best not to try to do this type of work on your own, as it can be complicated and destructive to your home.

Septic Drain Field

Some homeowners do not have access to a sewer line, and are instead connected to a septic system. This is a contained wastewater management system located on the property, usually underground.

In a septic system, wastewater is drained into a tank, which then digests organic matter and separates solids from the wastewater. In conventional septic systems, the tank is then drained into the surrounding soil by way of a leach field, or other mechanism designed to allow for slow drainage. This soil is known as the septic drain field.

So, if you have a septic system rather than a connection to a centralized sewage system, there is a chance that your water softener is draining into your septic drain field. There are a few more options for a discharge zone, and we will go over those now. 

Dry well

A dry well is a receptacle in the ground on your property meant to collect the backwash from your water softener. This hole is lined with a porous material that allows the spent brine to seep into the ground slowly. Slow seepage prevents the mineral content or ph of the ground from changing quickly. With more time to drain, ph levels can normalize and minerals can be diluted by rainwater. 

This is a good option for homeowners who are wary of draining spent water softener brine into their septic system, or don’t have access to a drain connected to a sewer system. 

Dry wells can often be installed by homeowners themselves, although it does require a bit of digging and pipe work to route the water softener backwash. Just make sure this type of drainage is permitted in your area before you spend time, money, and energy on this project.

French drain

A french drain is very similar to a dry well. With this system, water softener backwash is directed outside and into the ground, like with a dry well. The main difference is that this discharge zone is more of a ditch instead of just a hole in the ground. 

Stretching across the bottom of the ditch is a drain pipe with a series of small holes. These small holes allow for slow drainage into the surrounding soil, preventing shock to the environment. 

This method is easier than a dry well in that it doesn’t require a deep hole. Before deciding on a french drain or a dry well, be sure to check with local regulations. The laws in your area might prohibit this type of outdoor drainage entirely.  

Regulations Regarding Water Softener Drainage

As we mentioned before, it’s important to check with local regulations to see what you are permitted to drain, and how. Outdoor drainage, as seen with the dry well and french drain, is prohibited in some areas that source public drinking water from the groundwater. 

Similar laws prohibit this type of drainage into storm drains as well, so it’s important to consider this when deciding on your discharge zone. If you are in doubt, or the local laws are confusing, it’s best to consult a professional plumber. They deal with these regulations constantly, and can quickly give you an answer.


Now that you understand the purpose behind a water softener drain, and the different options available, you can decide which course of action is best for your home.

The most common method of this type of drainage is to utilize the floor drain in the house, but there are other options available if it’s impossible to install a floor drain in your home. Some of these drains don’t necessarily require professional work, but it is best to be aware of what discharge zone you can utilize, and any relevant regulations.

Whichever drain method you choose, this is a great feature to have in your home. It may take a bit of work upfront, but a water softener drain will definitely save you stress and expense in the long run.

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