A new analysis of water consumption suggests
approximately 20% of the world's aquifers are being overexploited.
Major agricultural regions including the Central Valley
in California, the Nile delta in Egypt and the Upper Ganges in India and
Pakistan are using water faster than it can be replenished, according to
researchers from McGill University in Canada and Utrecht University in the
Netherlands.
Their findings, published in the journal Nature, cover
nearly 800 aquifers worldwide. The data estimates each region's water footprint
(how much water is extracted for drinking and water irrigation) and the rate at
which that water is being replenished.
Overall, the consumption footprint for the studied
aquifers is about 3.5 times bigger than the water contained in them.
"The effect of this water use on the supply of
available water will be very different," write the researchers.
"Until now, there has been no way of quantifying the impact of such
agricultural groundwater use in any consistent, global way."
The net effect of overconsumption is that approximately
1.7 billion people in Asia are living in areas where underground water reserves
are under threat, according to the research.
To read the Nature article:
