Water softener backwash has a big impact on any environment. Because of the high salt concentrations within the brine, it can severely damage any water or soil's ecosystem.

It is therefore important to handle the disposal of any backwash with care before we turn the whole world into something that resembles Death Valley.

Luckily there are a lot of options when considering what to do with, or where to discharge your water softeners backwash, from simply running it into the ground to using it to kill off weeds or deicing your driveway.

What Does Water Softener Backwash Contain?

Before we look into where we can get rid of your water softener backwash let's consider what backwash consists of, so we can take this into account when choosing the best option.

During daily operation, a water softener swaps out calcium and magnesium ions (which are the root cause of water being hard) for sodium ions. When the system starts to run out of sodium ions to swap it has to be 'recharged'.

By running sodium-rich water from the brine tank of your system through the resin the calcium and magnesium ions are flushed out and replaced by fresh sodium ions allowing the system to restart producing soft water.

What we end up with after such a 'recharge' is the so-called backwash which consists of water with high concentrations of sodium, low concentrations of calcium and magnesium, and in some cases, depending on your water source, trace amounts of iron or other impurities.

Run It Into The Ground

The simplest way to drain your water softener backwash is to simply run it onto the ground, however, because there is a lot of salt in the backwash it can be very harmful to the ecosystem and/or the local water treatment facilities.

Therefore, keep in mind that in some places local rules or regulations may apply that prohibit you from using this option.

Avoid Discharging Your Backwash Near Other Water Sources

After sodium is mixed with water they are not easily separated, you cannot simply remove sodium by boiling or filtering the water, instead, you would need specialized equipment to separate the two.

As high concentrations can have severe negative effects on your health it is important to avoid your backwash from ending up in your water supply.

If you source your water from a local water well make sure that any drain is located at a maximum distance, a minimum of 100 feet, and preferably downhill from the source of your well to avoid any contamination.

When you are in doubt of the distance between your drain and the well it might be worth looking at off-site solutions for your backwash.

Avoid Plant Or Animal Rich Environments

Not only humans are negatively affected by high sodium concentrations, but plants, grass, and animals could also suffer negative impacts.

It's best to avoid draining your backwash into any freshwater ponds or lakes. If you decide to use it for watering vegetation, and your plants cannot survive in high salt concentrations, be sure to properly dilute the brine with extra water to lower the salt concentration.

Drain Options For Your Water Softener

As long as your water softener system is in service you will need to dispose of the brine water regularly. Therefore, it is best to look into structural solutions that will allow you to drain your system automatically.

Let Your Water Softener Drain Directly Into Your Local Sewage System

The most convenient solution for draining your system is connecting it directly to your local sewer system. Do however keep in mind that some municipalities and local areas might have rules and regulations in place that restrict draining backwash into the sewage system.

Construct A Custom Homemade Drainage Solution

If a local sewage system is unavailable to you or local restrictions prevent you from using it to drain your system the best option is to construct your custom drainage solution.

The trick is to use a solution that will dilute the salts over larger areas with a French drain or septic drain field or releases the backwash over longer periods like with a dry well.

For more ideas and information about drainage solutions for your water softener system check out this article.

Other Uses For Water Softener Discharge

If for some reason the previously mentioned options do not fit your situation, you might consider using your water softener backwash for other applications like killing weeds or deicing your driveway.

Killing Weeds

As mentioned above vegetation and saltwater is not a great combo. That however makes it perfect if you want to get rid of some.

In a concentrated form water softener backwash is a perfect weed killer on for example your driveway or patio deck. Don't try to use it in your flower bed or vegetable garden, as your precious plants will perish along with all the weeds.


Saltwater has a lower freezing point than water without salt. Therefore, up to certain temperatures, it can be used to deice your driveway during the colder seasons.

Keeping Your Vegetable Garden Free Of Slugs

Slugs hate salt as it dries them out and can potentially kill them. Pouring or brushing it around your garden can prevent slugs from entering and devouring your precious vegetables.

Because the salt could hurt your plants be careful with the amounts of backwash you add as well as the proximity to your garden.