Racing to the Bottom
The drought in large parts of the country is being blamed on paucity of rains. Indeed, that is the immediate cause of these troubles. But people have contributed much to the making of this disaster by over extraction of groundwater. Rains have been failing periodically from the time immemorial but that did not lead to the kind of distress seen at present because in those days groundwater reserves were full and people could survive by extracting the same during the drought. People have extracted the water that was stored in these aquifers for ages to cultivate water guzzling crops like grapes, banana, red chilies and sugarcane. This had led to lowering of the level of the groundwater aquifers. The cushion that these storages provided in periods of drought has been exhausted. Thus the present drought has assumed alarming proportions.
The farmers are paying huge electricity bills to pump out water from great depths. It is a race to the bottom. Every farmer has to deepen his bore well because his neighbour has deepened his bore well. The total amount of water extracted remains unchanged. It is determined by the amount of water that percolates into the earth every year during the monsoons. Previously the rainwater was percolating 20 feet into the earth and getting extracted. Now it is percolating 500 feet into the earth and being extracted. The total amount of water that is extracted has remained unchanged. However, every farmer is spending more diesel and electricity to pump out the same quantity of water from greater depths. Also harmful chemicals like arsenic that were lying dormant at lower depths are pumped out with water and are leading to a huge health crisis due to arsenic poisoning in West Bengal and Bihar. Previously these chemicals were lying dormant in the depths. Rainwater was percolatirg to, say, 20 feet depth while the arsenic layer lay at, say, 100 feet depth. The live water did not touch the arsenic. Now the water percolates to 500 feet depth. It passes through the layer of arsenic and absorbs this chemical. In the result the water extracted from bore wells is poisonous and not fit for drinking.
People are per force having to install purification appliances and incurring additional expenditures. Fluorides are causing similar health crisis in Rajasthan.
The subject of water is within the powers of the State Government in the Constitution. The Union Government cannot directly intervene in this matter. However, it has advised the State Governments to enact laws that require that new bore wells will have to obtain a license. The intention is good but this will not help the existing bore wells that are already leading to the depletion of ground water table. This depletion due to existing bore wells will continue even if new bore wells are not installed. The correct way is to specify the maximum depth till which a pump can be placed in the bore well. Say, a depth of 200 feet is specified. Every farmer will then draw water only from 200 feet. Presently the water percolates to a depth of say 1000 feet before being extracted. Then water will percolate to 200 feet and get extracted. Same amount of water will be extracted as previously. Everyone will gain by spending less for extraction. But this requires strict implementation so that every farmer draws water from a specified depth only.
It is also necessary to remove the hidden subsidies that encourage water extraction. Some states are providing free electricity to farmers. This encourages the farmers to extract more water.
Then the government must prohibit the cultivation of water guzzling crops in areas where ground water is depleting. Chilies are being grown in the deserts of Rajasthan, cotton in Gujarat aid grapes in the dry areas of the Deccan Plateau. Rich farmers are making deep wells and extracting the water. It is necessary to prohibit the cultivation of such crops in such dark zones. The Government must make an assessment of the available rainfall and expected percolation of groundwater in each block of the country. Then it must be assessed which crops can be cultivated in the available water. All other water guzzling crops must be banned. Then there will remain no need for the farmers to extract large amounts of groundwater. The supply of groundwater must be curtailed by specifying the maximum depth of a bore well. The demand for groundwater must be curtailed by banning water-guzzling crops that are not suitable for cultivation in the area.
The present government policy is to make large reservoirs like Tungabhadra, Tehri and Bhakra and store water for providing irrigation in lean periods. Such storage leads to evaporation of 10 to 20 percent of the water. That is a net loss to the country. Moreover a huge waste of water takes place in the command areas. Canals bring plentiful water here. The farmers have no incentive to use the water carefully. These dams also lead to the reduction of irrigation in the downstream areas. A stretch of about 150 kilometres from Hathnikund to Sonepat in Haryana has seen reduction in irrigation because water of the Yamuna River has been diverted at Hathnikund. The increase of irrigation in the command areas is at least partially nullified by the reduction of irrigation in such downstream stretches. The same water can be stored in underground aquifers. Water can be pushed into the earth in the monsoons by making "percolation wells." Water can be diverted from the flooded rivers and stored in such aquifers. The water can be extracted by bore wells in the lean season. This will have three benefits. One, the evaporation loss will be prevented. Two, the farmer will use the water judiciously because he will have to pay for the electricity used in pumping the water. Three, the country will be saved from the huge environmental impacts of large reservoirs.
Vol. 48, No. 47, May 29 - Jun 4, 2016