With increasing reduction in per capita water availability, India is facing the threat of becoming a water scarce nation. FE discusses the challenges and possible solutions
Punjab, also known as the foodgrain bowl of the country, grows about 11 tonnes of foodgrain (mostly rice and wheat) from one hectare per year with a crop intensity of roughly around 200%, which means that from an area of 4 million hectares, farmers produce crop equivalent to crop generally produced from an area of 8 mh in other parts of the country.
The net result is that in 1973, the water table in Punjab, which played a key role during the Green Revolution era, was at around 10 metres in 80% of the agricultural area. By 2009, the ground water available at that level reduced to only 40% of the area. Agricultural scientists say annually, the water table has been declining by as many as 3-4 metres.
?Punjab would dry up soon if we continue to grow rice and wheat. Not only would we not be able to grow paddy, but cultivating wheat would also become difficult. That would upset the economy of the state. It can have a serious upheaval in the countryside,? says Gurcharan Singh Kalkat, chairperson, Punjab State Farmers? Commission, who was also former director, agriculture, Punjab, and former vice-chancellor of Punjab Agricultural University.
The scenario is no different in neighbouring states of Haryana and Rajasthan where over-exploitation of groundwater for agriculture purposes has led to serious shortage of sweet water in many regions.
Continuous depletion of ground water because of agricultural use and rising demand from cities and industrial use has posed a serious challenge to the country?s water security. As Union water resource minister Harish Rawat said, ?We have about 802 over-exploited talukas, 169 critical talukas, and 523 semi-critical talukas as far as ground water situation is concerned. It calls for a serious all-round action programme to augment ground water resources in these areas.?
The ministry of water resources data indicates that out of 5,723 assessment administrative units (blocks, taluks, mandals, watershed) of the country, 839 units are ?over-exploited?, 226 units are ?critical?, 550 units are ?semi-critical?, 4,078 units are ?safe? and 30 units are ?saline?.
So alarming has been the depletion of groundwater that the government has decided to go for aquifer mapping. ?We have decided to put the ground water situation in the public domain, which calls for participatory management culture and community participation at the village, taluka and district level,? an official with the water resources ministry said.
Vanishing rivulets and tributaries
Another alarming trend that has emerged in the past two decades or so is that most of the water springs in hilly and semi-hilly areas have vanished, for reasons yet to be ascertained by scientists. It has resulted in the drying up of many of India?s perennial rivulets and tributaries, including small local lakes, during non-monsoon seasons. ?It has already adversely affected the water flow of some of our major rivers,? says a water resources ministry official.
The official acknowledges that encouraging water harvesting and smaller storage structures in these upstream catchment areas will reverse the trend. ?We are constituting a committee to go into the details and plan for rain water harvesting in these areas, and building small structures in the Himalayan, and sub-Himalayan regions,? he says.
The National Water Policy of 2012 recommends the integrated water resources management approach, which considers river basin or sub-basins as a unit for planning development and management of water resources. The government believes that this approach will help in not only increasing water use efficiency, but also minimising damage to the soil, and will help in mitigating flood problems in several parts of the country.
The water resources ministry has decided to undertake satellite mapping of the flood-prone areas under the flood management programme. The water use efficiency needs to be improved through continuous water balance and water accounting studies.
Due to population expansion, increasing urbanisation and rapid industrialisation, availability of water is not in consonance with its competing demands. Official data says the per capita availability of water has reduced significantly from 1,816 cubic metre in 2001 to 1,545 cubic metre in 2011. By 2050, the per capita availability of water will further decrease to 1,140 cubic metre.
Officials acknowledge that the country is facing a crisis that is multi-dimensional and which would be compounded due to climate change. ?We are now already a water stressed nation, and with further reduction in per capita availability of water, we will soon be a water scarce nation,? says Rawat. Even to meet this requirement, in 2050, India needs storage capacity of 450 billion cubic metres (BCMs). At present, the country has a water storage capacity of 253 BCM.
Need to restore old irrigation projects
The Planning Commission and the Union Cabinet have put emphasis on accelerated irrigation benefit programme, which also includes support for extension, renovation and modernisation of existing projects. The scheme for repair, renovation and restoration is also being accepted by the states, having an outlay of R6,235 crore in the 12th Plan (2012-17). Officials agree that due to a high number of pending major and medium irrigation projects, the water availability for the agriculture sector has not increased significantly. At present, there are 388 pending projects that are due for completion across the country. With the rise in water availability through canals, groundwater depletion, particularly in some northern states, could be curbed to a large extent.
?We are also giving priority to dam rehabilitation improvement projects for improving the safety performance of the existing dams,? G Mohan Kumar, special secretary, ministry of water resources, said. The government is also bringing out a dam safety Bill that would address the repair and maintenance of more than 5,100 dams across the country.
On the pricing mechanism front, the government is working on a system that also acts as an incentive for saving and disincentive for waste. Experts point out that ?all points of water supply, especially in urban areas, should be metered to boost conservation and ensure recovery of user charge?.
Waste water treatment technology has developed due to the significant contribution of scientific and engineering fields. This has led to the growing use of waste-water in agriculture worldwide. However, in terms of area irrigated by untreated waste water, India is far behind.
The Commission for Agricultural Costs and Prices (CACP), in a report on price policy of sugarcane, has stated that average water requirement for producing 1 kg of sugar in Uttar Pradesh and Maharashtra is 187 litres and 57 litres, respectively. ?Future growth of cane in Maharashtra is likely to be severely hampered by scarce water supplies unless much of sugarcane is put on drip irrigation or varieties are evolved that use less water,? says the CACP report.
It?s time for the government to launch promotion of a mandatory water audit, including those for drinking water purposes. ?We are focusing on incentivising the use of efficient irrigation practices, recycling of water, including waste water in different manners,? Rawat observed.
