Groundwater is the lifeline of India’s water security, catering to more than 60% of irrigation needs and 85% of rural drinking water requirements. However, recent findings from the Central Ground Water Board (CGWB) Annual Groundwater Quality Report (2024-25) and incidents such as the detection of uranium in breast milk in Bihar and the sewage-contamination tragedy in Indore highlight that India is facing a “silent emergency” of aquifer poisoning. The crisis has shifted from one of quantity (depletion) to quality (toxicity).

Major Sources of Groundwater Pollution

1. Agricultural Activities

• Excessive use of chemical fertilizers and pesticides leads to leaching of nitrates, phosphates, and toxic residues into aquifers.
• Over-irrigation causes percolation of contaminants such as urea and insecticides.
• Ex- Haryana and punjab region

2. Industrial Effluents

• Discharge of untreated effluents containing heavy metals (lead, arsenic, mercury, cadmium) and chemicals into soil and water bodies.
• Leather tanning, textile dyeing, paper mills, and chemical industries are major contributors. For example kanpur

3. Domestic Sewage and Solid Waste

• Seepage from unlined septic tanks and open drains contaminates groundwater with pathogens, nitrates, and organic matter.
• Leachate from municipal solid waste dumps introduces harmful chemicals and microplastics.
• Ex: mass illness in Indore

4. Mining and Quarrying Activities

• Acid mine drainage and leaching of toxic substances from abandoned mines pollute aquifers.
• Sand mining alters natural recharge zones, increasing vulnerability to contamination.

5. Salinity Intrusion in Coastal Areas

• Over-extraction of groundwater in coastal regions leads to seawater intrusion, raising salinity levels.
• Example Gujrat region

6. Arsenic and Fluoride Contamination (Geogenic Sources)

• Naturally occurring contaminants like arsenic (West Bengal, Bihar, Assam) and fluoride (Rajasthan, Andhra Pradesh) enter groundwater due to geological formations.

7. Leakage from Underground Storage Tanks and Pipelines

• Leakage of petroleum products, solvents, and chemicals from underground tanks contaminates aquifers.

8. Improper Disposal of Hazardous Waste

• Dumping of biomedical waste, e-waste, and radioactive materials without safeguards leads to long-term contamination.

Representation through map

Fig 1: Groundwater contamination hotspots

Consequences of Groundwater Pollution

• Health impacts: Waterborne diseases, fluorosis, arsenicosis, cancers, neurological disorders.
• Agricultural impacts: Reduced soil fertility, crop toxicity.
• Economic impacts: Increased healthcare costs, reduced productivity.
• Ecological impacts: Loss of biodiversity, degradation of wetlands and rivers.

 Way Forward

• Strict enforcement of Water (Prevention and Control of Pollution) Act, 1974 and Environment Protection Act, 1986.
• Promotion of organic farming and biofertilizers to reduce chemical leaching.
• Establishing real-time groundwater quality monitoring systems.
• Scientific management of solid and hazardous waste.
• Community awareness and participation in water conservation.
• Adoption of Integrated Water Resource Management (IWRM) and recharge techniques like rainwater harvesting.

 Conclusion

Groundwater contamination is a silent crisis that undermines India’s socio-economic development. Addressing both anthropogenic and geogenic sources through regulation, technology, and community participation is essential to safeguard this vital resource for future generations and fulfill the SDG 6 target.