GROUNDWATER POLLUTION
Environment
Groundwater contamination or pollution is the presence of certain pollutants in groundwater that are in excess of the limits prescribed for drinking water.
SEVERITY OF GROUNDWATER POLLUTION
Pollution Levels: 70% water resources are polluted – as per Composite Water Management Index
Arsenic contamination: many states like Jharkhand, Uttar Pradesh, Bihar have reported arsenic contamination above prescribed level
Salinity: Most Indian states have reported high salinity; approx. 25% of the Indo-Gangetic basin shows saline water
Uranium Contamination: Over 30 mcg/l in parts of north-western, southern and south-eastern India
Agriculture Impact: Over 90% of groundwater in India is used for agriculture
Depletion of Groundwater: Punjab is the highest exploited state followed by Rajasthan
2016 Parliamentary Committee: groundwater is “critical” in 9 states
CAUSES OF GROUNDWATER POLLUTION
1. Natural Causes
- Geological formations leach toxic chemicals like arsenic
- Anaerobic conditions release arsenic
- Fluoride minerals dissolve easily
- Decaying organic matter contaminates aquifers
2. Agricultural Causes
- Chemical fertilisers → nitrate contamination
- Poorly constructed wells allow seepage
- Indiscriminate extraction → salinity, uranium enrichment, seawater intrusion
- Skewed cropping: water-intensive rice/sugarcane in dry areas
3. Industrial Causes
- Heavy metals: lead, cadmium, zinc, mercury seep into groundwater
- Leaks from petroleum tanks and pipelines
- Hazardous sludge disposal
- Mining leaks arsenic, sulfuric acid, mercury
4. Municipal Causes
- Septic tank leakage
- Landfills lacking proper lining
IMPACTS OF GROUNDWATER POLLUTION
1. Environmental
- Algal blooms destroy aquatic ecosystems
- Biodiversity loss
- Reduced crop productivity
2. Economic
- High clean-up costs and health burden
- Falling land value
- Increased government spending on water treatment
3. Health
- Arsenic poisoning → cancer
- Fluorosis from fluoride
- Blue baby syndrome from nitrates
- Birth deformities
4. Social
- Farmer losses
- Marginalised communities suffer most
ISSUES WITH MANAGEMENT
- Poor real-time monitoring by CGWB
- Weak enforcement of pollution norms
- Groundwater use is decentralised → difficult monitoring
- Important parameters like pesticides often ignored
- Subsidies encourage over-extraction
- Waste treatment facilities are inadequate
GOVERNMENT INITIATIVES
- Swachh Bharat Mission: reduced groundwater pollution
- Artificial Recharge Plan: raising groundwater levels through managed recharge
- Water Act 1974: monitoring and prevention
- Arsenic mitigation in West Bengal; salinity prevention in Gujarat
- NAQUIM for aquifer mapping
BEST PRACTICES
Australia:
- Metered extraction
- Heavy fines
- Groundwater modelling
Chennai:
- Mandatory rooftop rainwater harvesting
FUTURE PROSPECTS
CAG Recommendations:
- Enforceable water quality standards
- Control pollution from sewage & agriculture runoff
- Incentivise aquifer recharge
- Treat wastewater for safe reuse
- Strict pollution law enforcement
- Install extraction meters
NITI Aayog Recommendations:
- Remove subsidies on electricity/diesel for groundwater extraction
- Community-based groundwater recharge
- Periodic reassessment of groundwater every 5 years
- Prevent seawater ingress in coastal areas
CONCLUSION
Groundwater pollution threatens food security, public health, and environmental stability. India, despite being the largest groundwater user in the world, faces overexploitation and widespread contamination. Strong monitoring, strict regulation, community participation, and sustainable agricultural practices are essential to prevent irreversible groundwater collapse.
PDF File:
No PDF attached
Subject: Environment
← Back