Water from the Cotswolds

Much of the rainwater falling in the Cotswolds disappears into the ground, soaking into the permeable limestone rock. It may eventually emerge lower down the hillside at a spring…

…or maybe not, as in here at what was once the source of the Thames.

Water that has trickled through limestone usually comes out pretty clean and carrying various dissolved minerals, particularly calcium. This usually results in a pleasant taste and gives the water health benefits, calcium being needed for strong bones. Thus it is excellent as drinking water.

But you don’t have to live in the Cotswolds to taste it for yourself. Several companies sell spring water that is bottled at its Cotswold source. These enterprises vary in size, with one company having a licence to remove 73 million litres of water per year from its borehole drilled into the limestone rock.

And then there are the water supply companies. They need to source enough water to keep it flowing down the pipes direct into our homes. Thames Water supplies 15 million customers. It gets around 40% of its water from groundwater and some of that comes from the Cotswolds.

So if the water is taken directly out of the rock and at a faster rate than rainwater puts it back, the spring may dry up.

The river may eventually appear from a different spring at a lower level. Compare this…

…with this.

But in the area of the source of the Thames, water was not just needed for drinking. A major project needed a water supply and it turned out to need much more than was anticipated. Find out all about it next week.