In the UK, about one third of the water that comes out of our taps is sourced from groundwater. The south of the country is particularly dependent on this underground store of water, with Cambridge Water and Cholderton Water relying entirely on the water found in the chalk and sandstone rock formations of the south-east.
After a dry winter, groundwater levels are lower than normal for the time of year, and scientists from the British Geological Survey are keeping a close eye on the situation.
Although February produced an average dose of rainfall for the south of England, it wasn’t enough to make up for the deficit resulting from a dry spell stretching all the way back to last summer. Met Office data reveals that, in the six months up to January 2017, much of the country was parched, with less than 70% of average rainfall falling across southern regions.
Normally, groundwater recharges during the winter, typically between October and March, when rainfall soaks through the soil and trickles into the underlying aquifer. This process becomes less efficient once spring arrives and plants start to grow, taking up the water before it has had chance to trickle down.
This year, the hydrographs for many boreholes reveal that recharge only started to get going at the beginning of the year. The borehole at Little Bucket Farm in Kent typifies this: water levels there usually start to rise in November but they didn’t “turn” until January. The hope, for water companies at least, is for sustained rainfall over the coming weeks.
