The Aquifer Project
What is an aquifer?
Here in the UK, we are fortunate to have access to fresh, clean water, literally on tap. No wonder most of us take water for granted!
In Brighton, Hove and Lewes, that water comes from the Brighton Chalk Block Aquifer. From the River Adur in the west, the River Ouse to the east, and up to the edge of the Downs, the land is shaped by this tremendous block of chalk.
This chalk is what forms our aquifer. An aquifer is when water is held below the ground in a permeable or porous rock layer. The chalk below us holds water like a sponge, as it is made up of millions and millions of microscopic fossils. One cubic meter of chalk can hold up to 660 litres of water!
The chalk is what makes our aquifer so special, chalk is a natural filter and has provided this area with clean water since it was first settled.
We rely on the aquifer for our water. The groundwater is pumped out of the aquifer through boreholes; this water is then treated and brought into your home and into your glass!
Watch the 4-minute video to learn more
FAQs
How does that water get into the ground?
It’s surprisingly simple, from rainfall. When it rains, the water permeates the soil and sinks into the chalk. It’s just as vital and just as fascinating as the flowing rivers we see. Groundwater has a life and journey of its own down there in the rocks. There are even amazing creatures called stygiobites that live in this water!
Another reason to love rainy days, the rain revitalises not only the plants above but the groundwater below. However, long weeks and months without the rain we need to trickle through the chalk and recharge the aquifer means trouble. September was the first month with above-average rainfall since February 2021 (Environment Agency, 2022), but that hasn’t helped the aquifer as it should.
Our groundwater levels are low, and our soil deficit is high. That means there’s a big difference between how wet the top of the ground is and how wet the soil underneath is, so our ground may be wet, but the soil is still dry.
What are chalk fossils?
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This is what chalk looks like under a microscope! Made up of millions and millions of fossils, from coccolithophores – single-celled marine plants.
Common misconceptions
Misconception 1: My tap water comes from a reservoir or river
Fact: Nope! Our tap water comes from the chalk aquifer, making Brighton, Hove, and Lewes unique. We don’t rely on water sources you can see, instead all of our water is held in the ground beneath our feet. In fact, most of the UK relies on groundwater.
Misconception 2: The aquifer is like an underground lake
Fact: The aquifer is water held within the chalk. That means there’s no giant lake or river holding it below us. It’s more like how water is held within a sponge.
Misconception 3: The aquifer is deep below the surface
Fact: Just like the chalk is right below us, so is the aquifer. Though there are places where the aquifer is far below, most of it is by the surface.
