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Nature: the primary source of your daily hydration

15 June 2016
Craig Goch reservoir, Elan Valley, Dwr Cymru

Have you ever wondered where your tap water comes from? This week's blog post is just about to answer that question.

The British Isles: all about rain?

Britain is famous worldwide for its frequent rains, showers, drizzles…. simply wet weather. It's hard to imagine but despite this climate, droughts are becoming more and more frequent. Water for public supply has - fortunately - been abundant but wouldn't have to be so in the future. There are 3 reasons for this:

1) as an island country, we don't have any river inflows from other countries

2) precipitation (rain) levels vary between years and will probably vary even more due to climate change

3) our groundwater resources are far lower than surface water flows: The UK has 10 billion cubic metres of groundwater produced annually, while surface water generation reached 144 billion cubic metres in 2014. You can check the evolution of groundwater levels on this interactive map, created by the British Geological Society.

The third point leads us to the obvious conclusion that most tap water originates from surface sources: reservoirs, lakes, and rivers in the UK account for 68% of the supply. The rest is from aquifers: about one third of tap water in England and Wales comes from underground sources, in Northern Ireland and Scotland this figure is 6% and 3%, respectively.

It's also interesting to note that despite the reputation for drizzle, our rainfall levels are probably not as high as you might think. London, for example, receives less rainfall than Sydney, Australia!

Learning about your water source

Knowing generic figures for the whole country can be interesting but it's understandable that you'd like to know more details about your particular situation. That of course depends on where you live and who supplies your water. In case you aren't familiar with that information, try our map to find out. Once on the website of your water company, the easiest way forward would be to use their search tool for "source". You should be able to find out the names of reservoirs, rivers or groundwater sources used in your region. In case you can't find what you're looking for, you can always contact the supplier and they'll be happy to answer your questions.

Tap water: taken from nature, treated for your health

Whether your tap water is of surface or underground origin, it is always from the natural environment. It might be that one day we will become like Singapore, where tap water partially comes from treated wastewater, but for the moment we don't "recycle" water in this country.

To understand the difference, have a look at the diagram below. This illustration, taken from our friends at EurEau, shows the standard system used in the UK: water is withdrawn from the source (reservoir, river, or aquifer), treated to eliminate any contamination and to comply with strict quality regulations, sent to consumers, collected, treated and cleaned as wastewater before being sent back into the ocean.

Water Cycle - credit EurEau