96.5 per cent of the total volume of world’s water is estimated to exist as oceans and only 2.5 per cent as freshwater. Nearly 70 per cent of this freshwater occurs as ice sheets and glaciers in Antarctica, Greenland and the mountainous regions of the world, while a little less than 30 per cent is stored as groundwater in the world’s aquifers. India receives nearly 4 per cent of the global precipitation and ranks 133 in the world in terms of water availability per person per annum. The total renewable water resources of India are estimated at 1,897 sq km per annum. By 2025, it is predicted that large parts of India will join countries or regions having absolute water scarcity.
Water and Indian economy
The Indian economy and society face daunting challenges in the water sector. The demands of a rapidly industrialising economy and urbanising society come at a time when the potential for augmenting supply is limited, water tables are falling and water quality issues have increasingly come to the fore. As we drill deeper for water, our groundwater gets contaminated with fluoride and arsenic. Both our rivers and our groundwater are polluted by untreated effluents and sewage continuing to be dumped into them. Climate change poses fresh challenges with its impacts on the hydrologic cycle. More extreme rates of precipitation and evapo-transpiration will exacerbate impacts of floods and droughts. It is no wonder then that conflicts across competing uses and users of water are growing by the day. Meanwhile, water use efficiency in agriculture, which consumes around 80 per cent of our water resources, is only around 38 per cent, which compares poorly with 45 per cent in Malaysia and Morocco and 50–60 per cent in Israel, Japan, China and Taiwan.
Demand and Supply of Water in India
Estimates of the annual flow of water available for human use after allowing for evapo-transpiration and minimum required ecological flow vary considerably. The water budget based on Ministry of Water Resources estimates shows utilisable water of 1,123 billion cubic metres (BCM) against current water demand of 710 BCM, suggesting more than adequate availability at the aggregate level given current requirements. The Standing Subcommittee of the Ministry of Water Resources estimates total water demand rising to 1,093 BCM in 2025, which reaffirms a comfortable scenario at the aggregate level even in 2025.However, more recent calculations, based on more realistic estimates of the amount of water lost to the atmosphere by evapo-transpiration, are less reassuring. Since the amount of water available is more or less constant, rising demands due to increasing population and economic growth will strain the demand–supply balance. The 2030 Water Resources Group (2009) estimates that if the current pattern of demand continues, about half of the demand for water will be unmet by 2030.
We must also recognise that water balances for the country as a whole are of limited value since they hide the existence of areas of acute water shortage, to say nothing of problems of quality. What is required is a much more disaggregated picture, accurately reflecting the challenge faced by each region. The exact level at which regions need to be defined would depend on the purposes of the exercise, as also unifying features of the region, such as basin and aquifer boundaries.
Need for a Paradigm Shift
These challenges can only be met through a paradigm shift in the management of water resources in India. This shift comprises the following elements:
• A move away from a narrowly engineering construction-centric approach to a more multidisciplinary, participatory management approach to our major and medium irrigation projects, with central emphasis on command area development and a sustained effort at improving water use efficiency.
• Since groundwater accounts for nearly two-thirds of India’s irrigation and 80 per cent of domestic water needs, we need a participatory approach to sustainable management of groundwater based on a new programme of aquifer mapping.
• A massive programme for watershed restoration and groundwater recharge must be launched by transforming Mahatma Gandhi National Rural Employment Guarantee Act (MGNREGA) into our largest watershed programme, giving renewed energy to the reformed Integrated Watershed Management Programme launched in the Eleventh Five Year Plan and launching a completely revamped programme on Repair, Renovation and Restoration (RRR) of Water Bodies.
• A new approach to rural drinking water and sanitation.
• All urban water supply projects to necessarily integrate sewage systems within them.
• Definite targets for recycling and reuse of water by Indian industry to move in conformity with international standards.
• Renewed focus on non-structural mechanisms for flood management.
• Vastly improved systems of water-related data collection and management as also transparency in availability of data.
• Adaptation strategies to mitigate the likely impact of climate change to be pursued under the National Water Mission (NWM).
• Perennial rivers with sufficient draft through the year could be the focal point of a renewed thrust to inland waterways transport as an environment friendly economical mode of transport compared to road and rail.
• A new legal and institutional framework for water based on broader consensus among the States.