Reverse osmosis systems waste a lot of water

How Much Water Does Your Reverse Osmosis System Waste?

A friend and fellow-JBay citizen asked me to share the following article about the reverse osmosis water purifying system.


I bought a reverse osmosis system a while ago, in the interest of my family’s health.

Being an inquisitive person, I took a closer look at its inner workings. To my astonishment, I found that it sends an enormous amount of waste down the drain.

How An RO System Works

Water enters the RO system, where it’s split into two parts, one drinkable, the other not.

What Happens To The Non-Drinkable Water?

Standard RO systems flush non-drinkable water, wherever. Most of them send the waste down the drain. It’s not sent back to the system for re-filtration. It’s not collected for alternative use either.

And the amount of waste far outweighs the potable water an RO system delivers.

I ran a few experiments…

For every five litres of potable water, the RO system delivered between 14 and 20 litres of waste.

That’s a waste of between 56% and 80%.

Armed with this info, I visited my father-in-law, who also owns an RO system.

He checked, and results were similar.

You Get Charged For Something You Don’t Use

Besides the fact that the RO system delivers a large amount of waste water, it reflects on my bill as consumed water. The municipality charges for this wasted water.

What if the municipality starts getting serious about water restrictions? What if they go the Cape Town route and restrict each JBay family to 100L of water per day?

How much of that water will your RO system flush down the drain?

With that in mind, I started collecting my RO system’s waste water. I urge you to do the same.

The waste water is fine for non-drinkable household use.

You can use it to wash dishes, flush toilets or water your plants.

This results in a 100% water usage.

Plus, you can continue using your RO system without feeling guilty.

How To Curb Water Wastage

A standard RO system’s waste water pipe connects to the house’s drainage system via a PVC tube, PVC nut and housing.

Unscrew the nut from the housing and place the PVC tube inside a large bucket.

It takes the RO system up to two hours to deliver between 14 and 20 litres of waste water.

Although it’s inconvenient, it helps me save plenty of water, and my water bill won’t explode.

If we all start doing this, JBay will see enormous water savings.

I hope you’ll join me in this battle against the drought.

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