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Context:

Groundwater contamination in India is no longer an invisible environmental issue, it has become a public health emergency, an agricultural productivity challenge, and a silent economic drain. With nearly 600 million Indians dependent on groundwater for drinking and irrigation, contamination poses grave implications for health, food security, and long-term development.

Current Status of ground water contamination in India:

According to the Central Ground Water Board (CGWB) Annual Groundwater Quality Report 2024, nearly 18–20% of tested groundwater samples across 440+ districts show concentrations above permissible limits for one or more contaminants.
These contaminants include:

• Fluoride: Endemic in arid and semi-arid regions such as Rajasthan, Gujarat, Telangana, leading to fluorosis risks among rural populations.
• Arsenic: High concentrations are reported from the Ganga–Meghna–Brahmaputra basin, especially West Bengal, Bihar, Assam, and Uttar Pradesh, consistent with WHO and UNICEF findings on global arsenic hotspots.
• Nitrate: Common in agrarian states like Punjab, Haryana, Uttar Pradesh, Karnataka, largely due to fertilizer overuse and sewage infiltration.
• Heavy Metals: Alarming uranium levels in groundwater have been identified in Punjab, Haryana, and parts of Delhi, with BARC studies confirming geogenic as well as anthropogenic sources.

NITI Aayog Composite Water Management Index (CWMI) highlights that 70% of India’s water is contaminated, making groundwater quality a critical national concern.

Drivers of ground water contamination in India:

• Industrial effluents: Industrial activities are a major source of chemical contamination in aquifers. Weak enforcement of environmental regulations, such as effluent discharge norms under the Water (Prevention and Control of Pollution) Act, and poor performance of Common Effluent Treatment Plants (CETPs), allow untreated or partially treated industrial waste to seep into groundwater. Industrial hubs like Vapi (Gujarat), Ankleshwar (Gujarat), and Kanpur (Uttar Pradesh) are hotspots where heavy metals, organic pollutants, and industrial solvents have contaminated local aquifers, threatening public health and agriculture. 

• Agricultural chemicals: Excessive and indiscriminate use of agrochemicals, including urea, nitrate-rich fertilizers, and synthetic pesticides, has become a significant driver of groundwater contamination. These chemicals leach into the soil and percolate into aquifers, particularly in regions with intensive agriculture. The National Academy of Agricultural Sciences (NAAS) has highlighted that nitrate contamination from fertilizers is a major contributor to methemoglobinemia (“blue baby syndrome”) in infants in rural India. 

• Over extraction of groundwater: Excessive extraction beyond sustainable limits alters the natural hydrology and often forces farmers to tap deeper aquifers, which tend to have higher concentrations of heavy metals and naturally occurring contaminants. The Central Ground Water Board (CGWB) notes that over-extraction not only depletes aquifers but also accelerates contaminant mobilization, compounding public health risks. 

• Untreated domestic sewage: A significant portion of urban and rural wastewater remains untreated, with only about 37% of sewage treated nationally (CPCB, 2023). Discharge of untreated sewage into rivers, ponds, and groundwater recharge areas results in microbiological and chemical contamination. 

Multidimensional implication of ground water contamination in India:

Water-Borne and Chronic Diseases

• Contaminants such as fluoride, arsenic, nitrate, and uranium lead to chronic illnesses.
• Fluoride contamination, prevalent in Rajasthan, Gujarat, and Telangana, causes skeletal fluorosis.

 Economic burden on households: Out-of-pocket expenditure for water-related illnesses remains high, pushing families into poverty traps. World Bank (2019) estimated that unsafe water and environmental degradation reduce India’s GDP by 6–8% annually.

Reduced Crop Yields: Heavy metals and chemical contaminants degrade soil quality. Studies indicate that farms irrigated with polluted water in Punjab and Haryana show 15–20% lower yields for staple crops like wheat and rice.

Rural Poverty and Inequality: Poor households cannot afford water purification or bottled water, deepening socio-economic divides. In Nalgonda district, Telangana, fluorosis-affected households face a lifetime of healthcare costs and lost earning potential.

Biodiversity Loss: Heavy metal seepage into wetlands and rivers affects aquatic ecosystems and terrestrial wildlife dependent on groundwater-fed habitats. CPCB 2023 indicates nitrate and heavy metal seepage into river basins is accelerating eutrophication and biodiversity loss.

Climate change and disaster vulnerability: Contaminated aquifers reduce resilience to droughts and extreme weather events, impacting agriculture and rural livelihoods. During the 2019 Maharashtra drought, dependence on polluted groundwater intensified malnutrition and water-borne diseases in affected villages.

Global Food Safety: Contaminated crops can lead to export rejections, as seen with rice and vegetables from West Bengal, affecting India’s global trade reputation. FAO (2022) warned that persistent heavy metal contamination threatens export competitiveness and food security.

Government measures to reduce ground water contamination:

Water Quality Standards

• The Bureau of Indian Standards (BIS) IS 10500:2012 sets permissible limits for contaminants in drinking water, including arsenic, fluoride, nitrate, and heavy metals.
• Central Pollution Control Board (CPCB) monitors industrial effluents and sewage discharges to prevent aquifer contamination.

Environmental Legislation

• Water (Prevention and Control of Pollution) Act, 1974: Regulates discharge of pollutants into water bodies.
• Environment Protection Act, 1986: Provides overarching legal framework for industrial effluent management.
• Industries like textiles, tanning, and chemicals are mandated to treat effluents before discharge, reducing heavy metal contamination.

Conclusion:

Groundwater contamination in India poses a multifaceted threat to public health, agriculture, and economic development. Driven by industrial effluents, excessive agrochemical use, over-extraction, and untreated sewage, it disproportionately affects vulnerable communities. Addressing this crisis requires integrated solutions—strict enforcement of regulations, sustainable farming practices, efficient wastewater management, and real-time monitoring—to safeguard water quality, ensure food security, and protect human capital.

Source: The Hindu