How much water does reverse osmosis waste

Clover Dane

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How Much Water Does Reverse Osmosis Waste

How much water does a reverse osmosis equipment waste?

Reverse osmosis equipment is the most appropriate to have tap water of the highest purity and quality at home. In recent years, domestic reverse osmosis devices have greatly improved their performance, and today, the amount of water that is discarded in the filtering process is much lower than it was a few decades ago. Thanks to technology, the loss of water in the reverse osmosis process is very small, so its impact on the utility bill is very little noticeable.

First of all, it is worth remembering the reason why when our reverse osmosis equipment is filtering the water, there is a quantity of it that is wasted. A domestic reverse osmosis equipment works thanks to a sophisticated system of microfilters, through which the water passes. The membranes are capable of separating, through osmotic pressure, those microscopic substances that are in suspension in the water, which are responsible for its poor quality and low purity .Do you want to know more about OSMOSIS equipment?

Osmotic pressure allows water to filter

Thus, in reverse osmosis equipment, after passing through the membranes, a part of the water, which is clean and healthy, goes to our tap so that we can consume it with full guarantee of quality and health. While another part, the one that is loaded with all the reject particles, is lost and wasted. Therefore, there is an amount of more that we take from the network and that we do not use. We would say that we keep the “good and clean” part of the water and discard the “bad and impure” part .

Thanks to the improvement in the efficiency and operation of the reverse osmosis equipment, in recent years the technicians of the main home water treatment companies have managed to considerably reduce the amount of water that is rejected in the osmosis equipment . In the past, for every liter of water left “clean” between three and five liters of water was wasted, while today the performance and efficiency of direct reverse osmosis equipment has improved considerably.

Reverse osmosis respectful of the environment and your pocket

How much water does a reverse osmosis equipment waste? In the case of reverse osmosis equipment, there are several models on the market, with different consumptions, but in general we can say that, currently, the most modern domestic reverse osmosis equipment has high performance. In this sense, they are the most respectful that there is, since some models are achieving consumption levels of up to 1 liter of discarded water for every liter of water produced for consumption.

Even if you think that with a domestic reverse osmosis equipment you will pay double the water bill, this is not totally true, since the total consumption of total rejected water in a billable period will be invaluable. You also have to think that the moment you install your domestic reverse osmosis equipment, you will stop buying water jugs and you will reduce consumption so much, since you will need less water, energy and detergents to carry out your household chores. home, such as the environmental impact of plastic on the planet. By installing a reverse osmosis equipment you will stop buying carafes and reduce the consumption of #water in your #home.

Innovation and development to reduce water consumption

And it is that the development of the technology that has been applied in the development and innovation in reverse osmosis equipment has allowed, in recent times, to considerably reduce the consumption of water in this type of apparatus. In the past, we saw that there were osmosis equipment from some manufacturers that had a water waste of between 70% and 75%. Practically, out of 10 liters of tap water, you could finally enjoy about 2.5 in your tap, since the rest went down the pipe.

Today, the landscape has changed a lot. Technology has advanced by leaps and bounds in the last decade and the domestic reverse osmosis equipment that has recently been launched on the market already consumes 2 liters of water for every liter of water produced. Thus, the current ratio is 1: 2, but we already have at our disposal some model of reverse osmosis equipment that, depending on the configuration, can consume 1 liter of water per liter of filtered water (ratio 1: 1) . As you can see, saving is very important. It is not only good for your pocket but also for the environment.

The truth about Reverse Osmosis Wastewater

In particular, there is a vast debate about how much water does reverse osmosis waste. We see that even many professionals argue over the wastewater of the RO system. Here, you will know about the truth and misconception of wasting the water by RO.

Why Does Reverse Osmosis Wastewater?

This article will lead you towards the real explanation of the wastewater. In reality, the concept of RO wastewater is not entirely a myth. But, it is a misleading claim.

Reverse osmosis is a popular process for the purification of water. This process involves the forceful movement of the water through different membranes. These membranes enable the elimination of all the harmful impurities.

Now the question is about where RO wastewater.  The answer is simple. There is a requirement of water for the washing of contaminants from the membranes. Water is an ideal substance for washing different things. So then, the water washes the membranes of the RO. As a result, the reverse osmosis produces wastewater.

Wastewater Ratio

The wastewater ratio depends on the system to system of reverse osmosis. Every system has its ratio of wastewater. Usually, the reverse osmosis system produces one gallon of purified water. In this case, the system wastes roughly four gallons of water.

Many important factors affect the wastewater ratio. Different factors affect the ratio of the wastewater differently. For instance, the most dominant factor is the water pressure. If the water pressure is below 35-40 PSI, then it wastes more amount of water.

The next important factor is the condition of the filter of the reverse osmosis system. The worn-out valve causes more loss of wastewater. In contrast to this situation, the well-maintained RO discharges less wastewater. With the above factors & other measurements, you can decrease the wastewater ratio.

Reverse Osmosis “Wastewater” Argument is incorrect

Many people support the drinking of municipal tap water. Such people take this point of RO system that it wastes water. They use this fact against to use the reverse osmosis. According to them, this system is wasteful & inefficient to meet the water needs. This perspective is misleading for different purposes.

Firstly, clean, purified water is the demand of a healthy body. In addition to it, the pure water is suitable for showering & cleaning dishes. The purified water ensures its great-quality and ideal for every task. Regular tap water is with many harmful contaminants.

When we drink this sort of water for drinking & cleaning, we may affect our health. Thereby, the filtration systems become an essential tool for household use. The reverse osmosis system is excellent for residential and industrial scales. Although they waste some quantity of water, yet they produce clean & pure water.

How Much Water Does Reverse Osmosis Waste

How can we minimize the wastewater?

There are some primary strategies for reducing wastewater.  Now, we will take a close look at these strategies. The following briefly explained plans help you to reduce the wastewater.

1. The Recycling Discharged Water

First of all, there are numerous methods for the recycling of discharged water. You can use the discharged/wastewater for different purposes. Many of the filter systems do the recycling process automatically. They continuously recirculate the discharged water in their filtration process. On the other hand, it increases the wear & tears on the filter. In this way, the life of the filter becomes short.

The second way to recycle this water is to use it in the hot water faucet. The hot water faucet does not need pure water. Mainly, you can efficiently use this discharged water in many appliances. Those appliances do not need pure water.

If you want to choose the second option, then remember one most important thing. The RO wastewater is with high concentrations of impurities. Therefore, there is no significant use of this water.

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2. Check Your Water Pressure

The second way to reduce the wastewater is to check the water pressure. As we above-mentioned, the low pressure of water will lead to wastage of more water. You can check the information on the water pressure of your house quickly. But if you face any difficulty, contact the professional. So, you will able to know about the water pressure of the house.

There is a specific range of water pressure. If the water pressure is lower than that range, then it leads to more wasting of water. The pressure of water must remain between 35 to 40 PSI. Through the pressure reducing valve, you will know the pressure.

Sometimes, many people observe that there is no problem with water pressure in their houses. If this is your case, then contact the authority of local water. Maybe the issue of the water pressure is from their side.

3. Perform Regular Maintenance

The third essential way to reduce the waste of water is the regular maintenance of the system. The RO system needs maintenance. It is not like to set the system and forget about it. In general, this system will not need high-maintenance. But, you have to check the system after every short time.

Most of the RO systems have five stages of filters. It also includes an RO membrane. Every filter and membrane has a lifespan. After that lifespan, you have to change them.


In conclusion, the wastewater ratio is 4:1. Usually, this system wastes four gallons of water for purification one gallon of water. This numerical fact is accurate. Now, you know about how much water does reverse osmosis waste. Through this article, it is not true to say that this system is wasteful.

You can quickly reduce the ratio of wastewater with different strategies. Wherefore, the RO system will not waste a large amount of water. Overall, the system is excellent, and you can use the wastewater for different purposes. The discharged water is necessary for the purification of water. The wastewater removes all the contaminants from the filters. This water is essential for the washing of the filters.