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Role of groundwater usage by industrial sectors
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Saturday, 28 December, 2019, 12 : 00 PM [IST]
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Dr Prakash Kondekar
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Water is not solely a local, national or regional issue that can be governed at any of those levels alone. On the contrary, global interdependencies are woven through water and decisions relating to water used by industries, at local and national levels. Water used at river basin or regional levels often cannot be isolated from global drivers, trends and uncertainties.
Agriculture has been the lifeline for millions of Indian farmers since the Green Revolution in the 1960s and groundwater has played a vital role in irrigating water-hungry crops such as rice to feed India’s ever-growing population.
Climate change is a central external driver that affects both water and demands for all uses directly. Mitigation measures are concentrated around the reduction of energy consumption and carbon emissions while adaptation means planning and preparing for increasing hydrological variability and extreme weather events, including floods, droughts and storms which in turn will have an effect on use of water in industries.
Addressing water challenges necessitates interventions across an entire economy, undertaken by strong institutions with the authority and leadership to take a proactive rather than a reactive role in water management, to drive the productive use of water across sectors within the framework of environmental sustainability. It also considers the water used in various industries. Members of the water community have the duty to inform and provide guidance on decision-making and to regulatory authorities on how to use and manage the resource sustainably, so as to optimise and share its many benefits, industry-wise.
Water demands and uses are often managed in silos with each focussed on meeting specific developmental objectives, rather than as part of an overarching and strategic framework that balances different water uses in order to optimise and share its various benefits across society. This fragmentation increases risks to the sustainability of water resources as well as to the different development objectives that depend upon limited supplies. Climate change exacerbates this problem still further.
Present status of groundwater
- 54% of India’s groundwater wells have declined over the past seven years and 21 major cities are expected to run out of groundwater by 2020.
- India uses an estimated 230 cubic kilometers of groundwater per year - over a quarter of the global total.
- NITI Aayog Composite Water Management Index (CWMI) report states that the majority of states have scored less than 50% in the source augmentation of groundwater resource index.
- The water situation in India is already dire, with nearly 600 million people facing high to extreme water stress, according to the NITI Aayog report.
- Why water scarcity in India?
- It is mostly manmade due to excess population growth and mismanagement of water resources, in general and industries in particular…e.g.,
- Inefficient use of water for agriculture. India is among the top growers of agricultural produce in the world, hence consumption of water for irrigation is highest.
Traditional techniques of irrigation cause maximum water loss due to evaporation, drainage, percolation, water conveyance and excess use of groundwater. The solution lies in extensive use of micro-irrigation techniques such as drip and sprinkler irrigation.
- Rapid industrial and construction business, is ignoring traditional water bodies that have also acted as groundwater recharging mechanism. It needs revival of traditional aquifers.
- Sewage and wastewater drainage into traditional water bodies.
- Release of chemicals and effluents into rivers, streams and ponds, by the chemical and textile industries. Strict monitoring and implementation of laws, is required.
- Lack of on-time de-silting operations in large water bodies that can enhance water storage capacity during monsoon, so as to add to the water storage levels.
- Lack of efficient water management and distribution of water between urban consumers, the agriculture sector and industry.
Reasons for groundwater depletion
- Increased demand for water for domestic, industrial and agricultural needs and limited surface water resources lead to the over-exploitation of groundwater resources.
- Groundwater depletion is due to frequent pumping of water from the ground without waiting for its replenishment.
- Intensive cultivation of water-intensive crops leads to depletion of groundwater resources.
- Discourage water-intensive crops which consume a lot of water.
- Water contamination as in the case of pollution by landfills, septic tanks, leaky underground gas tanks and from overuse of fertilisers and pesticides lead to damage and depletion of groundwater resources.
- Deforestation, unscientific methods of agriculture, chemical effluents from industries, lack of sanitation also lead to pollution of groundwater, making it unusable.
Effects of groundwater depletion
- Groundwater depletion will force us to pump water from deeper within the Earth, which is unsustainable.
- Large bodies of water such as rivers and lakes will become shallower from groundwater depletion.
- Depletion of large aquifers will affect our food supply and biodiversity.
- Groundwater depletion may also lead to salt contamination in drinking water.
Solutions to overcome water scarcity problems
A simple addition of a ‘water free’ male urinal in homes and industries can save well over 25,000 litre of water, per year per industry.
We need to change our dish washing methods and minimise the habit of keeping water running.
Every independent housing colony must have rainwater harvesting facility.
Wastewater treatment and recycling for non-drinking purposes.
Very often, we see water leaking in many factories, in public areas and colonies. A small steady water leak can cause a loss of lakhs of litres of water per year.
Although the trends in groundwater are confined to the northern part of India, it is really a national problem. In some of the states, extraction exceeds recharge from monsoonal rainfall. Recharging groundwater levels back to normal in such region may take up to 50 years.
Another culprit contributing to plunging water tables: weaker monsoonal rainfall due to climate change. Rising sea surface temperatures in the Indian Ocean may be linked to this decline.
Crops should be grown in which region according to the water availability, which has not been the focus. For instance,where region has a semi-arid climate but it grows rice, which depletes groundwater and is highly unsustainable. Ideally, rice is not the suitable crop there. The crops do not need all of the water pumped; they just need a small fraction of the water. We end up losing a lot of this water. The traditional flood irrigation in India accounts for huge water loss through evapotranspiration. This system could be replaced by drip irrigation or spray irrigation.
Most of the water pumping for industry happens from deep wells, in small towns.
Way forward
- Research and scientific evaluations should be done before forming any policy for industrial use of water.
- Water depletion can be controlled by power saving which in turn saves water.
- By encouraging farmers and industries to adopt various techniques for saving of water, roughly 20% of the groundwater used annually.
- Traditional methods of water conservation should be encouraged.
- Technology should be used extensively for determining the relationship between surface hydrological units and hydrological units below the ground.
- Artificial recharge of tube wells, water reuse, afforestation, scientific methods of agriculture should also be done.
The time to take initiative has arrived.
(The author is hon director, Indian Institute of Naturopathy, Mumbai. He can be contacted at drprakashk5@hotmail.com)
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