The water we bathe in, cook our food in and drink from our taps needs to be safe. This is a fundamental right of modern living. But while many of us understand that the water from our taps begins life in a reservoir and then gets passed through a water treatment plant before finding its way to our homes, few know exactly what happens at that treatment plant.

You’re probably thinking that, if you have a decent water filter installed, the water should be safe to drink right from the source? But there are a lot of subtle and not-so-subtle steps involved in making your tap water safe for consumption. Let’s start at the beginning.

Direct from the source

If you live in the UK, chances are your water will flow from a reservoir located just outside your general area. This water is then sent via a network of underground pipes to a treatment plant, which makes the water safe to drink. There are five steps that take place within this plant.

1. Coagulation

The first piece of the puzzle adds chemicals to the water to neutralise the dirt and other particles that found their way into the water either during its time in the reservoir or in the pipes on the way to the plant. Chemicals often used in this process include salts and metals like aluminium and iron.

2. Flocculation

In this stage, the water is mixed together with additional chemicals to form larger particles known as flocs. These appear as cloudy cells floating in the water.

3. Sedimentation

This is where the solid particles are separated from the water. The flocs settle to the bottom as they’re heavier than the water and only the clearer water that remains moves on to the next part of the process.

4. Filtration

The water separated from the flocs is passed through filters made from sand, gravel or charcoal to remove smaller dissolved particles, bacteria and parasites from the water. This also helps remove any lingering bad odours. Some treatment plants will also use a process known as ultrafiltration which uses incredibly small pores or reverse osmosis, which is a similar process used by home water filters.

5. Disinfection

Finally, before it can be sent to your home, a range of additional disinfectants such as chlorine will be added to kill off any lingering contaminants. This will also hope to kill any germs in the pipes between the facility and your tap. However, the plants will also endeavour to keep the chemical levels safe and in this balancing act, imperfections can remain. The water will be safe to drink, but it could be safer.

While water treatment certainly makes our drinking water safe to drink, adding a water filter to your home will ensure that you’re 100% happy with the quality and safety of the water you use every day.