Where has all the water gone?

Water resources are under severe stress today. About one-fifth of the world’s aquifers have almost dried up and large number of traditional water bodies such as tanks, ponds and lakes are depleting at a frightening pace.

A joint report of the World Health Organisation and Unicef on Progress on Sanitation and Drinking Water (2013) indicate that globally 768 million people remain without access to an improved source of water.

The Inter-Governmental Panel on Climate Change (IPCC) Report on Climate Change (2014) warned that about 80 per cent of the world’s population already suffers a severe threat to its water security.

Clearly, the world is witnessing an unprecedented crisis. Is it about having too little water, or one of managing water so badly?

A joint report of the WHO and Unicef (2012) estimates that 97 million Indians lack access to safe drinking water. A shocking study points out that an estimated 150 million women days are lost annually in fetching water alone.

Vast acreage of crops has withered away due to paucity of water. The Consortium of Farmers’ Organisations have reported that more than 20 per cent of the farmers in the Cauvery Delta Region alone have stopped farming due to water shortage; while a few of them either have committed suicide or have migrated to cities as daily wage earners. Are there any steps that can be taken to mitigate or prevent such a bleak scenario?

As per the estimates of the Central Water Commission (CWC), the average annual utilisable water (surface and groundwater) of the country is only about 1,121 billion cubic meters (BCM).

Due to continuous use, the total and per capita availability of water has also been declining sharply.

For instance, the per capita availability of water was 1,816 cubic metres in 2001, but declined to 1,544 cubic metres in 2011.

Increased population pressure along with competing demand for water from different sectors (drinking, agriculture, industry and energy) are reported to be the main reasons for declining water availability. The data published by the Central Water Commission indicates that agriculture alone accounts for about 85 percent of all water use, mostly drawn from groundwater.

This was also highlighted in the Standing Sub-Committee Report on Assessment of Availability and Requirement of Water for Diverse Uses in the Country (2000).

Of the 6,607 blocks assessed by the Central Groundwater Board (CGWB), close to 32 per cent of blocks have been classified as semi-critical, critical or over-exploited with situation deteriorating rapidly. Is there any possibility of bringing down the water use in agriculture?

Among the various options available readily, micro-irrigation (includes drip and sprinkler) is an effective method. Field level studies in Tamil Nadu and other regions have shown that drip and sprinkler irrigation saves about 50 per cent of water and electricity per acre, while increasing productivity substantially in various crops suitable for this method of irrigation.

The MS Swaminathan Committee Report on More Crop and Income Per Drop of Water (2006) has also highlighted the importance of micro-irrigation in checking reckless exploitation of groundwater.

Maharashtra has been very successful in promoting drip irrigation in various crops including sugarcane. It has decided to make drip irrigation mandatory for cultivating sugarcane.

Canal irrigates about 18 million hectares in India, but its water use efficiency is only 35-40 per cent. Volumetric pricing of irrigation water as advocated by the Vaidyanathan Committee Report on Pricing of Irrigation Water (1992) if implemented on a full scale in canal areas can lead to efficient use. The National Water Policy (2012) too has outlined the need for volumetric pricing of water.

The cropped area of water guzzling crops such as paddy, wheat, sugarcane, banana has been increasing in India. Appropriate output pricing policies need to be announced to control the expansion of water guzzling crops.

Efforts also need to be taken to institutionalise and strengthen community based water management.

The age-old technique of collecting and storing of rainwater should be made mandatory.

The government should also take immediate steps to repair, restore and renovate traditional water bodies which help recharge the groundwater aquifers.

Water conservation initiatives should not remain a mere slogan.

Naryanamoorthy is Professor, Alagappa University. Alli is Assistant Professor, Vellore Institute Technology. March 22 is World Water Day.