Groundwater is a significant source of water for irrigation, drinking, and it serves numerous environmental functions. While often deemed as “enigmatic”, its ubiquity and selective shielding from surface hydroclimatic processes makes it more resilient and reliable than surface water. Global groundwater withdrawals account for nearly one third of all water abstraction and more than two billion people worldwide rely on it as a primary source of water.
Importance of Groundwater
Groundwater is also difficult to study and govern, and thus manage due to its invisibility and the ease with which it can be tapped with private capital, especially without the formal approval of water regulatory authorities. The basic tenet of managing groundwater involves maintaining the abstraction rate (extraction rate) well within the recharge rate (essentially a ‘refill’ from other water sources or rain) of the aquifer and achieving a balance between the natural flow regime and its extraction. The ease and cost of accessing groundwater has contributed to a silent revolution by water users across the globe — this rapid increase in groundwater use has raised questions about the sustainability of this rampant use. When compared to surface water, groundwater is easier to access with a pump and unlike surface water sources, the water does not need to be transported from a faraway source if an aquifer exists right under the land at the point of usage. Further, the capital and negotiations with other water users needed to secure said access to water is also lesser for groundwater. The large storage volume per unit of inflow when compared with surface water bodies makes the groundwater more resilient in drier periods and thus reduces its dependency on timely precipitation; this also increases the reliability of groundwater as a source for water as the climate changes.
The large spatial extent of aquifers also makes it easier to access it unlike surface water bodies which are limited to its areal extent on the surface, this makes the groundwater bodies more ubiquitous. The overburden/land cover of aquifers also provides an important ecosystem function by filtering the water that percolates into the ground. The soil traps contaminants at low concentrations and microbes in the top layers of the soil to some extent and the water that percolates into the aquifers tends to be of a higher quality. Groundwater resources are heavily stressed around the globe and the next section explores the challenges of groundwater management.
Challenges in groundwater management
1. Over-abstraction and quality issues
Since groundwater provides great social and economic benefits at a rather low cost, unscrupulous use of the resources for agriculture, industry, and human consumption has led to quick depletion of the resource. This depletion has resulted in falling of groundwater levels, subsidence of land (sinking land) in many regions, salinization of water in the upper reaches of wells, increased the costs of extraction, and has damaged aquatic ecosystems. The depletion of groundwater may be in the form of an actual fall in groundwater levels, making it difficult to extract more water with existing infrastructure or it can be the reduction in actual volume of freshwater from the groundwater stocks. Water users in arid and semi-arid regions rely on groundwater during the drier months and consequently increase abstraction during these months with the hope that the precipitation in the wetter months would recharge the aquifer but with increased instances of extreme weather events and climate change, many aquifers have exceeded their long-term sustainable yield. This further exacerbates the drawdown (a time lag between withdrawal and fall in groundwater level) in aquifers. The heterogeneity of an aquifer in terms of its geology is also significant since the drawdown and pumping rates between an aquifer in alluvial system and a hard-rock system can vary by rather large margin.
The invisibility of groundwater and the delayed response of the drawdown in aquifers makes it difficult to quickly ascertain stark changes in groundwater. Quantitative depletion of groundwater can only be addressed by increasing recharge or by reducing discharge. Often cited as a “fugitive” resource, groundwater usage for agriculture instigates a competition to pump faster and larger volumes of water. India is the largest groundwater user in the world with the most contribution of non-renewable groundwater abstraction for irrigation at 68 km3/yr. Abstraction rate of groundwater in India accounts for nearly 25% of the global groundwater abstraction rate; 20 million wells exist in India and 1.5 million of these are in Maharashtra. Groundwater can receive natural and anthropogenic contaminants from various sources. Industrial discharges, agriculture, groundwater over abstraction causing salinization, chemical spills, human wastes, and disposal of wastes are some of the main human induced causes of groundwater pollution.
Natural contaminants can include substances that occur naturally in overburden and rocks, such as metals — iron, manganese, and arsenic or chlorides, fluorides, sulfates, or radionuclides. Increasing geogenic contamination, (i.e. the naturally occurring concentration of certain elements in nature) due to over-abstraction of groundwater is on the rise in India. Arsenic (As)contamination is a real threat in the water bodies along the Ganges and As contamination across Indian communities has increased by 1.5 times in the past five years.
2. Ignoring the linkages between surface and groundwater bodies
The term ‘hydroschizophrenia’ is often used when describing management of groundwater. It points towards the separation of the management and legislation governing surface water bodies and groundwater entities. Since surface water and groundwater have different physical characteristics such as the time taken to respond to abstraction, biophysical roles, and resilience to surface geomorphological processes, the protective management and regulatory frameworks also need to account for these nuances. The resulting differentiation of groundwater and surface water leads to mismanagement even though the two are closely linked and essentially drive each other. Despite groundwater’s significance in global water supplies, it receives little regulatory and management attention as compared to more visible surface water bodies such as river and lakes. This selective focus on surface water bodies overlooks the connections that exist between the hydrological cycle and limit the scope of influence of relevant authorities looking to implement water legislations and policies.
Since the main contenders for water are the domestic users and agriculture, the competition for water between these sectors is bound to increase in the future as climate change effects intensify and water resources face depletion. Enacting legislation and policies with limited focus in terms of ‘surface water’ and ‘groundwater’ perpetuates the misnomer that they are disparate and further contributes to reducing the effectiveness of water governance by restricting the scope of the implementation of said frameworks. There exists uncertainty in accurately delineating aquifers, mapping ground water flow and its hydraulic connection to surface water resources. As usage of groundwater to meet human demands and simultaneously satisfy natural flow increases, surface water deficits and exploitative groundwater usage need to be addressed in a collective manner. The common pool nature of groundwater thus calls for management strategies and regulations which consider the peculiarity of its nature and flow, and align it with the larger goals of water governance. While some states in India like Maharashtra have specific laws protecting its groundwater, its surface water remains largely ignored. India also has much ground to cover at the federal level even though water is a “state subject” meaning that individual states address water management & policies themselves with certain exceptions.
3. Intertwined property rights and access to groundwater
The interactions between the hydrological entities and society makes the common pool nature of a hidden resource like groundwater more convoluted than it seems . When viewed through the ‘biopolitical’ lens, it is seen that states regulate both — water resources and the average citizen’s water use patterns to ensure the health and productivity of the citizenry. While both land tenure rights and water rights have the basic purpose of allocation of valuable resources, modern formal land and water rights are heavily influenced by European notions such as the civil law and the common law traditions which allowed for prior appropriation of water. An aquifer’s fuzzy hydrogeological boundaries combined with clearly demarcated land ownership atop it leads to conflicts around land rights and the right to use the water under it. In cases of aquifers underlying privately owned land, each land holder aims to leverage their own technology and economic might to extract the maximum benefit from the land and water resources.
If a number of land owners exist over a common-pool resource of a large underground aquifer, the possibility of them ‘impinging’ upon the first owner’s privilege is high. Such situations lead to competition, with the potential to turn into a conflict. The state is expected to protect the rights of the landowner and by extension, their right to the water under the land. The nature of groundwater also demands that the state regulate the extent of use, lest it causes harm to the environment or other users. Further, assigning unregulated “ownership” to groundwater resources paves the way to overexploitation of the resource. The act of imposing groundwater usage caps or embargoes on private land can often lead to a state of expropriation of the land and the water rights associated with it.
In India, the remnants of the common law, overlapping with civil law often lead to conflicting senses of entitlement to water. It is important to also note that, the Indian Easements Act of 1882 stipulates that, “The right of every owner of land to collect and dispose within his own limits of all water under the land which does not pass in a defined channel and all water on its surface which does not pass in a defined channel”. It also outlines that unreasonable pollution of said water shall not be carried out by landowners.
The groundwater situation in Maharashtra
The 2021 GAR Special Report on Drought estimates that severe droughts in India could cost the country nearly 2- 5% of its GDP. The socio-economic nature of competition and conflicts for water in Maharashtra is quite complex
due to unplanned infrastructural growth, caste politics, a wide disparity between economic strata of citizens, and growing water demand compounded by climate change. Water users in the rural regions often compete to satisfy their basic needs for water since urban pockets are growing at a tremendous rate and water from these rural and peri-urban regions is often diverted to the city for their needs.
The arid central region of Marathwada in the state often faces severe droughts which have been linked to farmer suicides due to financial troubles in the last decades. Inappropriate crop matching with environmental conditions such as planting water-intense sugarcane or cotton in these water scarce regions has led to increased distress migration and human rights violations in these regions. The mean depth to groundwater between 2009 to 2018 as compared to the levels in May 2019 (pre-monsoon) shows a significant drop in 76% of the wells in the state; and 23% of the wells show a drop in groundwater levels as compared to November 2019 (post monsoon). The state is also experiencing a decline in the quality of groundwater. Nitrate pollution which can be traced to agricultural runoff, nitrogen-based fertilizers, animal manure, and sewage is increasing in the groundwater. Further, unchecked release of effluents from industrial zones and sugar processing factories has caused the groundwater water quality to plummet. The aquifers in the state are also concentrated with Iron and Manganese among other metallic contaminants.
While numerous challenges exist in managing groundwater, an increased awareness among water users and citizens coupled with robust policies and regulations such as the Maharashtra Groundwater Act (2009) serve as the light at the end of the dark ‘water scarcity’ tunnel.
