More than half of south Asia's groundwater too contaminated to use. Salinity and arsenic affect 60% of underground supply across vast Indo-Gangetic Basin, a river basin supporting more than 750 million people in Pakistan, India, Nepal and Bangladesh. The Indo-Gangetic basin accounts for about a quarter of the global extraction of groundwater – freshwater which is stored underground in crevices and spaces in soil or rock, fed by rivers and rainfall.
The biggest threat to is not depletion but contamination. Up to a depth of 200m (650ft), some 23% of the groundwater stored in the basin is too salty, and about 37% “is affected by arsenic at toxic concentrations”. Groundwater can become salty through natural and manmade causes, including inefficient farmland irrigation and poor drainage. Arsenic, too, is naturally present, but levels are exacerbated by use of fertilisers and mining. Arsenic poisoning of drinking water is a major problem in the region.
Fifteen to twenty million wells extract water from the basin every year. The new study – based on local records of groundwater levels and quality from 2000 to 2012 – found that the water table was, in fact, stable or rising across about 70% of the aquifer. It was found to be falling in the other 30%, mainly near highly populated areas.
If you want the rational use of natural resources contact:
The World Socialist Party (India):
257 Baghajatin ‘E’ Block (East), Kolkata – 700086,
Tel: 2425-0208,
E-mail: wspindia@hotmail.com
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