Over-extraction, loss of natural recharge, and pollution are threatening India’s groundwater resource. Any hope for mitigating the looming groundwater crisis lies in understanding the irony of an invaluable yet invisible resource.
Jay Mazoomdaar brings to us the various facets of this irony and the impact it can have on the lives of the people.TerraGreen (TERI), March, 2010
Before delving deep into the groundwater scenario in India, let us look at the following figures.
This is what India’s Ministry of Water Resources says:
• Groundwater represents one of the most important water sources in India and accounts for over 400 cu km of the annual utilizable resource in the country.
• The total annual replenishable groundwater resource of the country is 433 BCM (billion cubic metre).
• Keeping 34 BCM for natural discharge, the net annual groundwater availability for the entire country is 399 BCM.
• The annual groundwater draft is 231 BCM, out of which 213 BCM is for irrigation use and 18 BCM is for domestic and industrial use.
This is what the experts have to say:
• Groundwater usage in north India is the highest in the world.
• Across India, the mean rate of drop in the water table has been one metre in every three years.
• From August 2002 to October 2008, groundwater depletion in Rajasthan, Punjab, Haryana and Delhi was equivalent to a net loss of 109 cu km of water—double the capacity of India’s largest surface water reservoir.
• These states are losing at least 30% more of their groundwater resources than previously estimated by the government.
And this is what is predicted:
• By 2020, severe groundwater shortage will hit several Indian states, especially Delhi and Mumbai.
• By 2025, many parts of India could run out of groundwater! Groundwater has been the most important and the most reliable fresh water resource in India.
About 80% of the country’s rural water supply for domestic uses is met by groundwater. At the same time, farmers’ dependence on it has grown phenomenally over the last century, as more than half of India’s irrigated land is fed by groundwater.
Paradoxically, groundwater is also an invisible resource. It is difficult to accurately determine how much groundwater is left and in what condition. And its invisibility leads to this very reliable resource being taken for granted. Worse, since groundwater is a key resource for poverty alleviation and economic development, the obvious results are over-exploitation and contamination.
The crisis
Increasingly, across the world, the dependence on groundwater has risen, leading to indiscriminate withdrawal. Simultaneously, the depleting stock is being contaminated with agricultural chemicals, industrial discharge, and urban waste…often irreversibly. In most cases, the plunder is at best overlooked by the government and at worst, facilitated with subsidized power and other concessions. With 60% of the global population and just 36% of the Earth’s available freshwater share, Asia faces the grimmest crisis.
In the Azraq basin in Jordan, for example, reckless groundwater withdrawal has lowered the water table by up to 16 m between 1987 and 2005. By 1993, springs and pools in the Azraq Oasis had dried up completely. In the north-eastern plains of China, over 60 000 sq km receives spare rainfall. But this area has become the breadbasket of the country by extracting huge quantities of groundwater for irrigation. It is estimated that as much as 70% of the agricultural water needs are met by groundwater in this region. The water tables are falling rapidly, threatening agricultural productivity and food security.
Then, there is the problem of contamination. Already, 1.7 billion people lack access to safe water in the developing countries. More than 3 million people die from water-borne diseases each year in developing countries, the majority of whom are children under the age of five.
The most important water contaminants created by human activities are microbial pathogens, nutrients, pesticides, oxygen-consuming substances, heavy metals, and persistent organic matter. Water contaminated by microbes remains the greatest single cause of human illness and death on a global scale. These pollutants enter water systems through agricultural run-off; domestic and industrial effluents and inadequately treated wastewater discharge; erosion; mine and landfill leachate; litter disposal; and so on. Every aspect of our lifestyle and economy endangers the water sources on which we depend.
Approximately 2 million tonnes of human waste are released annually into rivers and streams around the globe, and an estimated 2.6 billion people still do not have improved sanitation facilities. In 8 out of 13 regions under UNEP (United Nations Environment Programme), less than 50% of the wastewater discharged into freshwater and coastal areas is treated.
In the other five regions, the proportion of treated wastewater falls below 20%. Projected increase in the use of fertilizer for food production and wastewater effluents over the next three decades suggests that there will be a 10%–20% rise in river nitrogen flows globally, continuing the trend of a spurt of 29% between 1970 and 1995 due to poor agricultural practices.
Food, at the cost of waterAgriculture and animal husbandry are water-intensive processes. To produce food worth one calorie of energy, one litre of water is needed. So, to satisfy the need of 3000 calories per person for a population of 6.5 billion on the Earth, our daily requirement of water is equivalent to a water body that is 1 m deep, 1 km wide, and 7 million km long—long enough to encircle the Earth 180 times!
The production of just 1 kg of rice and 1 kg of chicken require 1800 and 6000 litre of water, respectively! With growing demand for more and better food, triggered by a rapidly rising population and urbanization, all possible ways of increasing the supply are explored. And one such way is the exploitation of groundwater.
Across the world, crop yields in the areas that are irrigated with groundwater are often substantially higher than those irrigated by surface sources. India is no exception. Here, yields in groundwater-irrigated areas tend to be 1.2–3 times higher. As much as 84% of India’s agricultural output is groundwater influenced. In the five decades since independence, the net irrigated area in India went up from 20 to 66 million hectares—a jump of 330%. In the same period, groundwater-irrigated areas increased from 6 to 34.5 million hectare—a jump of 575%.
During 1970–94, groundwater-irrigated lands in India have increased by 105%, while surface water irrigated land rose by only 28%. It is estimated that the cumulative investment in groundwater structures in India is more than Rs 55 000 crore. And most of this investment is by individual farmers who have, since the early decades of independence, tapped into the country’s groundwater resources (with state support where initiative was missing) to get the benefit of new agricultural technologies.
Starting from the mid- 1960s, the introduction of new techniques and high-yielding crop varieties in the course of the Green Revolution saw greater dependence on groundwater irrigation. Farmers found that switching to a more reliable and controllable form of irrigation yielded bigger and better harvests, leading to overall prosperity.
The spin-off of these success stories was a chain reaction—more and more farmers were inspired to switch to groundwater to irrigate. Without adequate surface irrigation capacity, the growth of groundwater irrigation infrastructure as a private ‘resource’ was sudden and spectacular. More than just multiplying farmers’ incomes, the creation of these resources meant that more and more labourers were finding work in villages, lifting themselves out of poverty while being a part of the wealth generation process. Soon enough, extending sops to the farmers in terms of electricity to pump water became one of the trump cards of political parties and a staple of election manifestos.
The result was that, to this day, groundwater irrigation is unregulated and overexploited, and given the socio-economic factors in play, it is unviable for the government of the day to effectively regulate the usage. Several blocks of Punjab and Haryana are close to hitting rock bottom in terms of exploitation of groundwater, while in many districts across India, CGWB (Central Ground Water Board) studies put the decline in water levels at more than 4 m a year. But why not explore surface water?
The top–bottom link
As far as surface water is concerned, India gets about 4000 BCM of precipitation a year, including snow. But close to half of this quantity (1869 BCM) is the natural runoff in rivers. Accounting for evaporation, replenishable groundwater resources are about 433 BCM. But together with utilizable surface water (690 BCM), the per capita availability of water as computed in 1997 was 1869 cu m, well above the 1000 cu m yardstick denoting ‘water starvation’. The figure declined to 1820 cu m in 2001. And the IPCC (Intergovernmental Panel on Climate Change) in a 2008 report projected the per capita availability in 2050 at 1140 cu m a year, just above the water-starved mark. Another study cited a closer deadline for water stress—the year 2025!
What is worse is that even these figures do not show the real picture and could be misleading, as the water availability is hardly uniform. Varying rainfall and population density mean that while the Brahmaputra–Barak Basin might have a per capita availability of over 14 000 cu m of water a year, those living in the Sabarmati Basin make do with just about 300 cu m. In fact, researchers have found that many other basins such as Mahi, Tapi, and Pennar are already water-stressed.
Rich in surface water resources, India should not have groundwater depletion problems. But almost 85% of India’s surface water goes into the sea. India receives an average 600 mm of rain annually (which translates into 4 trillion cu m), but only about 15% of this is used for irrigation. The rest reaches the sea via the massive river systems. If India was to increase surface water use from the present 15% to 25%, most of the groundwater depletion issues would disappear.
The current scenario
Unfortunately, over the past five decades, indiscriminate exploitation of groundwater resources and simultaneous neglect of surface water systems – be it canals, bunds, or reservoirs – has led to dipping water tables and in some places, irreversible degradation of the source due to poor or no recharge, contamination, and more recently, saline ingress. While the early 1960s spurred the boom in sinking of tubewells – supported by government aid and subsidies in terms of power – over the consequent decades, increasing population pressure and rapid urbanization meant total dependence on groundwater for drinking water and domestic use, especially in the spiralling cities that power development.
As of March 2004, nearly 15% (839) of the 5723 blocks assessed by the CGWB and the states across the country were categorized as ‘overexploited’, meaning that extraction in excess of net annual recharge. Another 226 were ‘critical’, meaning that recharge just about managed to cover the exploitation. Some 30 blocks have already scraped the barrel, now left with only saline groundwater. With an average annual depletion of groundwater level of 10 cm, the north Indian plane – across Rajasthan, Punjab, Haryana, and west Uttar Pradesh – is on the brink of a water disaster.
A study in 2009 by Virendra Mani Tiwari from Hyderabad’s National Geophysical Research Institute, along with scientists of the University of Colorado, United States, said that the amount of groundwater pumped out across northern India is the highest in the world! Citing satellite data, the study said that the 54 trillion litres pumped out in the region – a 2000 km sweep from West Pakistan to Bangladesh along North India – contributes to a 5% rise in sea levels. Major cities in India like New Delhi, Kolkata, Chennai, and Mumbai face acute water shortage.
Urbanization has resulted in massive pressure on water supplies. The last report by the CGWB projected Delhi’s demand for groundwater for 2025 at 0.57 BCM (more than double of what it is now), with no water available for irrigation! The state of development of groundwater resources in the national capital is 170% in the negative. Even as of now, only 0.28 BCM of groundwater is available in a year. By 2020, severe shortage will hit Delhi, as well as Mumbai.
Compounding factors
The problems of coastal erosion and salinity ingress in groundwater is being felt more severely in the recent years due to the destruction of protective mangrove cover and reduced sediment discharge by rivers. Other human activities like rampant beach mining also add to the problem. As recently as the Asian tsunami of 2004, mangroves acted as a buffer in a number of stretches. Without the effective bio-fencing of mangrove cover or dune vegetation, coastlines are increasingly getting exposed to erosion.
A free-flowing river gathers sediments as it meanders inland and deposits the load when it reaches the sea. This sediment load compensates for much of the coastal erosion. But when a dam is built on a river to break its flow, the river’s sediment load settles in the dam’s reservoir. Globally, more than 50 000 large dams are in operation today. At least 100 billion tonnes of sediment has been retained in these reservoirs in the past 50 years, causing significant reduction in the flux of sediment to the coasts. From Egypt (Nile River delta) to Morocco (Moulouya wetlands) to Louisiana (Mississippi River delta), big dams exacerbate coastal erosion across the world.
Too many dams on rivers also mean that too little water reaches the deltas. This, in effect, results in limited percolation to coastal aquifers. On the other hand, restricted river fl ow forces coastal people to extract more and more groundwater, already under severe pressure due to a spurt in population along the coasts. It is this low-recharge-high-extraction scenario that makes coastal aquifers vulnerable to seawater ingress. Contamination, however, is an even bigger threat to the availability of quality groundwater.
In 2003, arsenic groundwater contamination was reported in Bihar. More recently, Uttar Pradesh and Jharkhand also followed suit. Combining the fi rst report of groundwater arsenic contamination in 1976 from Chandigarh and a few villages of Punjab (Patiala) in northern India of upper Ganga plain with Uttar Pradesh, Bihar, Jharkhand, and West Bengal, and that of Bangladesh, it appears that a good portion of the Ganga-Meghna-Brahmaputra plain – an area 569 749 sq km and a population over 500 million – may be at risk from groundwater arsenic contamination.
Also, present records show that 17 states in India are endemic for fluorosis. An estimated 62 million people in India, including 14 million children, suffer from dental, skeletal, and non-skeletal fluorosis.
The magnitude
‘If we compare the total amount of available water on the Earth to a water bottle containing 18 litres of water, the available freshwater is only three teaspoons. Add to this the groundwater stock which is just 1% of the Earth’s total water. Unfortunately, we are taking little care of this priceless reserve. Groundwater arsenic and fluoride contamination in developing countries could be more serious than any human tragedy known to mankind,’ warns Dr Dipankar Chakraborti, Director, School of Environmental Studies, Jadavpur University, Kolkata.
When we trace the growth of our so-called ecological footprint, water emerges as the biggest victim. While the world’s population increased by 300% in the 20th century, the use of water increased by 700%! Over a longer period of 250 years since the industrial revolution, carbon dioxide formulations in the atmosphere have gone up by approximately 36%, methane by 150%, and nitrous oxide by 16%.
Five years back, eminent water scientist duo Michel Meybeck and Charles Vörösmarty warned that ‘the global impacts of human interventions in the water cycle, including land cover change, urbanization, industrialization, and water resources development, are likely to surpass those of recent or anticipated climate change, at least over decades.’
In the same year, the UN (United Nations) declared 2005–15 as the International Decade for Action (Water for Life) ‘to enhance international cooperation in addressing the exploitation and degradation of water resources.’ But with half the decade gone, there is hardly any effective move towards inter-governmental agreements to protect trans-boundary freshwater systems.
The IPCC report does offer projections of how global warming will impact groundwater and rainfall patterns, but the latest UN World Water Development Report (2009) notes that ‘these impacts are likely to be small (and possibly negligible) compared with the stresses placed on groundwater systems by current socio-economic drivers’. Yet, inexplicably, if media reports are to be believed, about a month before the COP15 (Fifteenth Conference of Parties) in December 2009, the backroom boys in Barcelona decided not to have any mention of water issues in the negotiating text.
But even beyond the issues of food and health security involving billions worldwide, groundwater performs an array of ecological services which are often intangible. Across the world, the dry season flow in many rivers depends largely on catchment baseflow derived from groundwater discharge. A healthy groundwater level also ensures water availability in wetlands, one of the most biologically productive and diverse inland ecosystems. Groundwater, particularly during dry seasons, is a prime source for instream flows that is crucial for the maintenance of fisheries and aquatic ecosystems.
Ironically, the widely understood benefits of this invisible resource are those that follow its extraction – its ability to maximize agricultural output and therefore, material well-being of user communities. Their efforts, accordingly, are towards the maximum utilization of the resource rather than its conservation and prevention of source pollution. The economic dividends of exploiting the aquifer, in the public perception and in the short term, far override its environmental benefits as a drought buffer and a reserve.
But while the individual may be tempted by the short-term incentives, governments and policymakers cannot afford to lose their long-term focus if the world is to avoid water wars in the future. Water extraction is predicted to increase by 50% by 2025 in developing countries and by 18% in developed countries (World Water Assessment Programme 2006). Since nearly all industrial and manufacturing activities require adequate water supplies, this situation is likely to impede socioeconomic development and increase pressures on freshwater ecosystems.
At the global scale, the integrity of aquatic ecosystems – the state of their physical elements, their biodiversity, and their processes – continues to decline, reducing their capacity to provide clean freshwater, food, and other key services.
The way forward
It may not be too late yet. But reducing stress on groundwater systems requires reducing land-based pollution, rehabilitating degraded habitats, and conserving water resources. Similarly, replenishing water tables may require more than artificial recharging.
Once polluted, it becomes very difficult to purify groundwater aquifers. Pollutants become attached to the aquifer’s sand, soil, and rocks, and serve as a continuous source of contamination. Research has shown that overdraft can lead to aquifer compaction (reduction of pore spaces), stopping recharge. Even if recharge is theoretically feasible and sufficient water is available, the low flow rates which are characteristic of many fine grained aquifers can make the process so slow that little can be done on a human time scale.
In order to seek solutions, understanding the groundwater dynamics is also very vital. In Rajasthan, as Marcus Moench, Director of Institute for Social and Environmental Transition, pointed out that local communities often feel that groundwater overdraft problems get solved whenever rainfall is above normal. In reality, the water pumped out would have been underground for 100 to 20 000 years. And the recharge dynamics largely depend on the permeability of soils, since fl ow patterns do not depend much on the short-term fluctuations in rainfall. Besides, predominantly, natural aquifers are spread over vast regions, meaning localized events and efforts are unlikely to yield significant results.
Compartmentalized government schemes and incentives pertaining to blocks and villages, therefore, will most likely fail to reflect the recharge dynamics, not to mention groundwater conditions and utilization patterns. On the other hand, major quality problems can also depend on localized conditions. For example, the amount of arsenic found in water from a particular well may depend on the amount of organic matter available where the well was drilled. A well that runs alongside a tree trunk, buried deep underground, may have relatively more arsenic than a well drilled only a short distance away.
At another level, many usages and environmental values of groundwater depend on the depth of water and not on the volume available. In the case of the Ganga basin, for example, decline in water level would reduce base flows in streams long before the aquifer would face any threat of depletion. In certain stretches, the Ganga basin contains over 20 000 feet of saturated sediment. But dewatering of only the top few feet would have tremendous impact.
Given the complex factors at work, it would be simplistic to expect one piece of legislation to regulate or control the overexploitation of groundwater across the country, since the distribution of the resource and the demand are varied. A state like Arunachal Pradesh, for instance, has developed barely 0.04% of its groundwater resource, while at the other end, Gujarat has tapped into 76%. A composite solution, therefore, should focus on a clutch of measures tailored to every state’s peculiar conditions.
While in agriculture-intensive states, a move to regulate government subsidy for electricity to farmers could bear results, in others, development of surface irrigation networks would take the pressure off groundwater as the predominant source of irrigation. Most importantly, however, a shift in mindset is essential — groundwater needs to be looked upon as a community resource, not an individual asset. Management of groundwater resources at the level of villages and communities is likely to lead to better strategies for utilization and recharge.
In states like Punjab, Haryana, and Rajasthan, however, efforts need to be fasttracked to prevent further deterioration; it is too premature to even contemplate a turnaround for the over-exploited or dark blocks. For a start, political parties must stop patronizing indiscriminate exploitation of groundwater as a means to drum up vote banks.
Eventually, policymakers and governments will have to tackle the issue of equitability. From the climate change debate to the dynamics of carbon points, the objective is to make the biggest damager pay the most. In regulating the supply of groundwater and restricting approvals for exploitation, the poor, credit-dependent farmer who is seeking a late entry will be affected much more than the rich farmer who has thrived for decades on the very basis of such oversight.
On the other hand, continuation of status quo will mean higher costs of extraction as water tables fall in subsequent years, hitting the poor further. In case of water scarcity, the first to be affected economically are those who cannot afford deeper wells. The future course of action must safeguard against further marginalization of the poor. While access to groundwater needs is to be made equitable, so must be the responsibility for the resource. Sustainable management involves enrolling more and more user communities as stakeholders in the process, rather than just the owners.
To begin with, the state needs to step in as a participant in a sector it has so far left to individual whim and clout. Slashing subsidies and ensuring that the rich farmer pays for the groundwater he uses to irrigate his fields and that the urbanite picks up the bill for his wastage would pave the way for better management and distribution of the resources at hand, besides offering a genuine chance for replenishment.
At the same time, the demand for groundwater needs to be rationalized. Provisions for harvesting rainwater and artificial recharge must be made mandatory in future constructions. As a policy, the government needs to encourage micro-irrigation technologies that make much better use of water than flood irrigation; develop better surface irrigation capacity to reduce the stress on groundwater; encourage community participation in groundwater management to encourage sustainable cropping patterns; bolster supply augmentation strategies for more efficient recharge; and overall, promote conjunctive use of water.
Groundwater is a great driver of the economy and a great tool for poverty alleviation, and as a country we have drawn liberally on this vital yet invisible resource. It is time that we shift our mindset from resource development to resource management. Otherwise, it is our future that would dry up along with our groundwater resources.
(Acknowledgment: CGWB, SOES-JU, UNWATER 2007, WWAP 2006, IPCC, UNEP-GIWA, WHO, UNICEF, DFID, IWMI-TATA, M Moench, H Sud, A Narayanamoorthy, N K Garg and Q Hassan)
The author is an independent journalist
