Home Blog Water Stewardship Is the "Wastewater" Produced by the RO System Really Wasteful?

Is the "Wastewater" Produced by the RO System Really Wasteful?

by Dr. Jonathan Doyle - Updated September 08, 2020
The water filtered by RO system is fresher and healthier than bottled water, but there's a drawback to using RO: excessive wastewater. Let us explore how RO wastewater can be reused here in Waterdrop.
Reverse osmosis water purifiers provide us with clean, tasty, and safe water. They also safeguard us from waterborne diseases that are a potential threat to our lives.
Compared with bottled water, the water filtered by RO system is fresher, healthier and safer. It can effectively remove calcium, magnesium, bacteria, organic matter, inorganic matter, heavy metals, radioactive substances, and viruses in your tap water. The water filtered by RO system is pure, crisp, and refreshing.
However, there is a large drawback to using reverse osmosis water purifiers, though: excessive water waste. The wastewater percentage varies based on the use of an RO purifier. Most of the traditional RO system have a drain ratio of 3:1, and the best is only 2:1. Thankfully, reverse osmosis systems with reduced wastewater are available. The amount of its wastewater used is only one-third of what is produced by traditional reverse osmosis systems. Having said that, wastewater production is inevitable, no matter what RO system you use.
Are you curious about why water gets wasted in the first place? Reverse osmosis purifiers utilize membrane technology, which filters dissolved impurities. Any impure water that gets filtered out is what we refer to as reject water, a.k.a. wastewater.
As verified by professionals, wastewater is - and has always been on – unconsumable. The content of TDS (Total Dissolved Solids) in the water makes it undrinkable, and no one should bathe with this type of water, either. It usually contains organic matter and inorganic salts in deferring amounts that contribute to its unsustainability.
What to be mindful of before RO wastewater is used
Having said that, reverse osmosis wastewater has other uses in both your office and home.
Before we look at how wastewater can be reused, we need to go over some fundamentals. In doing so, we can avoid potential problems and issues that may arise.

What to be mindful of before RO wastewater is used

It is prudent to establish what the wastewater's TDS levels are before reusing it. If RO wastewater TDS levels are too high, it may not be reusable for anything. You should test the wastewater for any presence of chemical and inorganic impurities, such as sodium. Several RO systems out there have a display screen that tells users if the TDS in filtered water passes a standard level.

How is RO stored?

A reverse osmosis waste pipe can be extended and lowered into a large tank (the tank should be in a room beside the kitchen). The water that gets stored can be reused later for several purposes, including the ones listed below.
A compact submersible pump (such as the ones water coolers use) can be used to take water out of this tank. Simply lower the pump into the tank before connecting it to the power source.
Connect a water pipe to the pump's outlet to siphon water out of the tank, sans the use of a container or bucket. A large tank allows you to prevent an overflow of water. You will need to be wary of overflows if you use a bucket rather than a large tank.
The container, tank, or bucket used to store RO wastewater must have a broad opening so that deposits can be cleaned during regular intervals.

Five ways RO wastewater can be reused

Wash your car

A carwash consumes between 14 liters (if a bucket is used) to 75 liters (if hose pipes are used) of water. When you consider how scarce drinking water is, the use of excessive potable water in a carwash sounds ridiculously excessive.
We don't think it's necessary to have a car washed every single day. Use of RO wastewater won't harm your car, and is just as effective as regular water is.

Watering your home garden or plants

If you enjoy gardening or keep indoor potted plants, you can use wastewater to nourish them. This suggestion is especially helpful for residents of urban areas, since TDS levels in city water are usually quite low.
Watering your home garden or plants
You must check the water's quality and find out what kind of effect they have on plants. Attempt to use water on every variety for several days to see how the wastewater impacts your greens. This observation will help you understand which plants have a better hard water reaction.

Household chores

Floors will always need to be mopped, and utensils will always need to be washed. This should happen every several days, or perhaps every day, depending on how much traffic an area gets. Store some wastewater in containers and buckets, and keep them close to the sink. Use this wastewater every time you clean floors or do dishes.
Household chores
Wastewater can also be used to launder your clothes, too. Be mindful, though, that some delicate fabrics might have a bad reaction to the hard water based on its TDS content (in addition to other compounds).

Laundry pre-rinse

Your RO wastewater can be used when it's time to do laundry, but be mindful that high TDS levels in water could harm delicate fabrics. A majority of modern households have washing machines, which helps residents bypass plenty of effort and time. Unfortunately, such a convenience is at the expense of water usage. Use a large overhead tank to collect RO wastewater, then get the washing machine to use the collected wastewater. This suggestion is most effective for twin tub and semiautomatic washing machines.
Laundry pre-rinse
Image source: facebook

Flushing and cleaning toilets

Based on consensus, wastewater should not be used to bathe or wash your hair with. It can be used as toilet flushing water, and to clean up your faucet and bathroom fixtures. Do a test run on the water first to see if it results in any discoloration on certain surfaces, such as porcelain.
Are you in search of a reverse osmosis purifier that produces minimal (if not zero) wastewater? Have a look at the Waterdrop RO Water Purifier. Out of all the different RO systems out there, this product produces the least amount of wastewater – specifically, one-third of what its counterparts produce. Using this system can reduce your water bill and usage overall.
Further, the Waterdrop RO system's filtration performance is second to none. The system is certified and tested by NSF/ANSI against NSF International standard 58. TDS levels are reduced by as much as 94%. The system is NSF/ANSI 372-certified to have led free compounds. The Waterdrop RO system passed more than 400 chemical laboratory tests to ensure that it is free from over 400 chemical elements, some of which include Cadmium, Lead, Benzene, Formaldehyde, and Bisphenol A, among others.
To combat droughts, farmers occasionally take drastic steps. People who live in poor areas (in addition to many buildings) take the daily supply of water for granted. Each drop matters, and small steps taken by everyone results in big changes for the better.


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