A study based on satellite imagery, by the US National Aeronautical and Space Administration (Nasa), says that North India’s ground water table is dropping by nearly a foot every year. The estimation of total annual water extraction, at around 17.7 billion cubic metres (BCM) in four states (Punjab, Haryana, Rajasthan and Delhi) between 2002 and 2008, is 35 per cent higher than the government’s assessment of 13.2 BCM. The study, published in the latest issue of Nature, the peer-reviewed scientific journal, reckons the total water depletion in the region in this period at a staggering 109 cubic km, twice the capacity of the country’s largest water reservoir. Since the withdrawal of water is far higher than the recharge, this amounts to mining underground reserves built over thousands of years. The implications for the agriculture-based economy of the region as well as for national food security are obvious.
The gravity of the situation becomes clear when viewed along with the growing pollution of groundwater and the consequential deterioration in its quality, making it sometimes unfit even for irrigation, let alone drinking, in many parts of this belt. The Nasa study, therefore, does well to caution that the consequences of water loss at such a rate may include the collapse of agricultural output, a severe shortage of potable water, social conflict and human suffering. These are dire prospects, and underline the point that water management is one of the country’s greatest and most urgent contemporary challenges.
Mismanagement of the situation is unfortunately the order of the day. Reckless water mining is going on unabated in agricultural areas where the power used for this purpose is either free of cost or hugely subsidised. Alternative sources of water, often diverted to the cities, is also massively subsidised. Industrial users, like the producers of aerated drinks and bottled water, are guilty of both over-use and the contamination of groundwater. Much of this can be traced to the archaic law of the colonial period that gave land owners free and unlimited access to water underneath their land. This is fundamentally flawed as any underground water reserve is a dynamic common resource, and losses as well gains get evenly distributed throughout the aquifer.
Ideally, the extraction of water should not exceed 90 per cent of the normal annual recharge. This norm is seldom observed in the northern states as well as in other parts of the country. This led a Planning Commission working group on water resources to conclude in 2007 that the country would face an acute scarcity of fresh water in 35 to 40 years. The situation calls for an urgent response through legal and policy measures, including realistic pricing, to promote the sustainable use of water. A massive effort to promote rainwater harvesting, which will reduce dependence on underground water while enhancing the rate of its recharge, is a must in rural as well as urban areas. Indeed, this should be made mandatory.