By Ranjit Devraj, IPS News
Posted on September 4, 2009, Printed on September 4, 2009
http://www.alternet.org/story/142438/
India's current dry spell, brought on by an errant annual monsoon, is rapidly turning into a full-fledged drought as a result of reckless exploitation of groundwater resources for farming, experts say.
According to information available from the agriculture ministry, 246 of India's 626 districts have now been officially declared as facing a "drought-like" situation. Monsoon rains account for 75 percent of India's annual rainfall. Officials at the Indian Meteorological Department say this year has seen the scantiest season in the last seven years.
Government data shows that water levels in the country's 81 major reservoirs are now down to about 38 percent of normal levels and offering no margin for comfort.
"India's vulnerability to droughts whenever there is a slight deviation in the monsoon pattern has grown over the years because of excessive groundwater withdrawal to support intensive farming, particularly in the north-western states of Punjab, Haryana and Rajasthan," says Devinder Sharma, internationally known agriculture and food security expert. "At present rates of withdrawal, by 2025 all groundwater will have been exhausted."
Sharma, who chairs the independent New Delhi-based collective, Forum for Biotechnology and Food Security, says the situation is especially grim in the state of Punjab, where groundwater mining has for years exceeded natural replenishment. "Punjab, which provides nearly 50 percent of the country's food surplus, is paying a price for playing the role of granary to the nation," he adds in an interview with IPS.
Of Punjab's 138 administrative blocks 108 have been officially categorised as 'dark zones', where 98 percent of underground water has been overexploited.
Satellite images released in August by the National Aerospace and Space Administration (NASA) of the United States show massive depletion of groundwater storage in Rajasthan, Punjab and Haryana during the 2002-2008 period.
NASA's images indicated an average drop in groundwater levels by four centimetres a year, with about 110 cubic kilometres of groundwater having been lost during the six-year period that was studied.
If the current level of unsustainable over-consumption, mainly for agriculture, continues, India could face severe water shortages, NASA scientists have cautioned.
"Groundwater is extremely valuable as a resource which stores water during the wet years and makes it available in the dry years, so that people and farmers can survive droughts, whether part of the natural variability or related to climate change," says Matthew Rodell, a NASA hydrologist and lead author of the study, in the SciDev.Net portal. "However, groundwater must be managed sustainably, or in time this capability could be lost."
Rodell says 95 percent of groundwater withdrawal from the region was for irrigation, mainly for rice, wheat and barley. "If farmers shift away from water intensive crops, such as rice, and also implement more efficient irrigation methods, that would help," SciDev quotes him as saying.
NASA's projections based on tracking by twin Gravity Recovery and Climate Experiment (GRACE) satellites show that 54 cubic kilometres of groundwater are lost every year in the Indo-Gangetic plains, the world's most densely populated and heavily irrigated region.
GRACE satellites make detailed measurements of the earth's gravity to facilitate discoveries about the earth's natural systems.
Worse, the depletion rate has been estimated to be 70 percent faster this decade than in the 1990s. The withdrawals have been mainly for irrigation although urbanisation and industrialisation seem to be playing an increasing role. The NASA data roughly tallies with estimates from India's Ministry of Water Resources based on a simpler and cheaper method of drilling holes and measuring water levels four times in a year. This water level fluctuation method helps assess both how much rainwater is contributing to underground aquifers and reservoirs, and how much is being used.
A report released in June by hydrologists Rana Chatterjee and Raja Ram Purohit at India's Central Ground Water Board corroborates the overexploitation of groundwater in north-western, western and peninsular India. The hydrologists estimate that Indians use 231 billion cubic metres of groundwater each year, 92 percent of it for irrigation.
"Despite the dismal consequences of the irrigation policy, the fascination of the planners for costly projects has not diminished," laments Sharma.
"Traditional water harvesting and rain water collection practices do not find favour with the policy makers and planners for the simple reason that they do not need investment and budget allocations," says Rajendra Singh, leader of the Tarun Bhagat Sangh, a well-known non-government organisation which has been actively promoting simple check dams and traditional water conservation methods in arid Rajasthan, India's largest state.
Singh, winner of the 2001 Ramon Magsaysay Award for Community Leadership, says even now planners continue to overlook simple ways to conserve natural water bodies and underground reservoirs although they are the only way to drought-proof the country.
"As traditional forms of water storage and harvesting disappeared and rural irrigation was taken over by inefficient government machinery, ground water began to be exploited indiscriminately," adds Sharma.
Sharma believes that water shortages for farming can be resolved, at least partly, by following cropping patterns that are linked to water availability rather than the push for greater yields through the use of hybrids developed by scientists.
"At present, drylands are increasingly being brought under hybrid crop varieties that have high yields but several are water-guzzlers,'' says Sharma. "There is no sense in encouraging farmers in a desert state like Rajasthan to grow sugar cane. In fact, all kinds of hybrid crop varieties that require large quantities of water such as rice, sorghum, maize, cotton and vegetables are promoted in the dryland regions."
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