Our water treatment process

Have you ever wondered how the water that falls from the sky gets to your taps, clean and safe to drink?

Let’s start from the beginning.

You may have heard of, or even visited, our two main reservoirs, Arlington and Ardingly, and while they play a vital role in our water sources, just 8% of what we treat, pump and supply comes from our reservoirs. The rest comes from chalk streams, rivers, underground aquifers and boreholes.

Aquifers are an underground layer of water-bearing permeable rock, rock fractures or unconsolidated materials like gravel or sand.

Boreholes can be described as any narrow or small shaft that is drilled into the ground, where water can be abstracted from.

Chalk streams are a special type of river. There are only around 200 chalk streams in the world and 85% are in England!

We work 24 hours a day, 365 days a year top make sure the water we provide you with is of the best quality. So how do we get the water to your taps?

To ensure that the water we supply is clean, fresh and safe to drink, there is a 9 step treatment process involved.

From screening, aeration, primary treatment and clarification, to filtration, sludge treatment, advanced treatment, and disinfection, your water is tested at every stage to ensure it’s as safe as possible. In fact, we carry out more than half a million tests a year on our water!

Once treated, the water is immediately pumped to storage reservoirs around our network and boosted through 9,000 miles of pipes into your homes and businesses.

The entire process from source to your tap usually takes around 2 hours, and when you think about it that’s pretty impressive!

We often think of ourselves as guardians of the environment, and we work hard to protect and enhance it for future generations.

As well as making sure there is enough water for our customers to use, it’s also essential to look after the rivers and raw water sources we abstract from, leaving enough water for the wildlife within them to thrive and survive.