The Cambridge Dictionary definition of greywater is: “water that has been used before, for example for washing, that can be stored and used again, for example in toilets”. If it isn’t recycled, greywater ends up going straight down the drain and into the sewerage system.

However, greywater is clean enough to be used for some purposes. In fact, you’ve probably already recycled greywater at home. In times of drought, most of us have followed the Royal Horticultural Society’s advice to collect water from showers, baths and sinks and use it to water the garden. Greywater recycling in your business premises is a larger, automated version of that.

How businesses use greywater

If, for example, your hotel, university or leisure centre has shower facilities for employees or customers, you can significantly reduce your water and wastewater bills by recycling the greywater from them. At the moment, you're only using it once in the showers before it's flushed down the drain. But you don’t always need the water to be potable for all uses - when it comes to flushing toilets, washing vehicles, pavements or yards, or watering grounds, greywater is perfectly all right.

In simple terms, you’d no longer have to pay for water you use to wash your hands with and pay for the water you use to flush toilets with. By using the greywater from the sink and diverting it into the toilet cistern, you’ll only pay once for water you’ll actually use twice. Another advantage is that by reducing the amount of water you flush away, you will also reduce your wastewater costs.

If you scale that up to the size of your business, then you’re looking at significant savings. And not just in monetary terms.

Boost your sustainability credentials by saving water

At COP26 last year, we interviewed Carolyn Hogg, Managing Director of Cascade Water Products, about the need for greywater. She told us: “Water is an energy-consuming sector. Greywater reuse is the future. So, individuals, young and old, local and national governments, businesses, developers and construction companies need to be aware of and educated on the benefits of greywater reuse and reducing water consumption.”

In fact, there are business reasons to make the effort to make your brand more sustainable.  As Carolyn said: “Businesses are now expected to demonstrate their green credentials when applying for tenders. However, water use is often not included. Thus, greywater as a solution is not included. So, be ahead of the pack and investigate greywater reuse.”

The additional green benefit of recycling greywater is that less water will need to be abstracted from our rivers and aquifers. The less water we abstract from the environment, the less stress both will be under and the more water will be available for humans and nature. Greywater recycling also decreases the amount of wastewater released back into the environment, helping to prevent water stress.

Greywater systems

Greywater systems are becoming increasingly popular with businesses. They come with pumps and filtration units which partially treat the greywater before it’s used. It’s important to note, however, that if your greywater contains food debris, it will have to be treated in a septic tank. This will come at a small cost, but the savings you’ll make on your water bills will quickly cover the installation and running costs.

Contact us today to learn more about the services that Castle Water provides, including business water services, water efficiency audits & wastewater management.


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