India is grappling with increasing groundwater nitrate contamination, posing significant health and environmental risks. Excessive use of nitrogenous fertilizers in agriculture has been identified as the primary cause. The latest data from the Central Groundwater Board (CGWB) underscores the urgency of addressing this issue.
Current Status of Groundwater Nitrate Levels
- Sample Analysis: Out of 15,239 groundwater samples, 19.8% exceeded the safe nitrate limit of 45 mg/L, a marginal improvement from 21.6% in 2017.
- Districts Affected:
- 2023: 440 districts with unsafe nitrate levels.
- 2017: 359 districts affected.
- Key States Affected:
- Rajasthan: 49% of tested samples exceed limits.
- Karnataka: 48%.
- Tamil Nadu: 37%.
- National Concern: 56% of India’s districts report nitrate levels above permissible limits.
Seasonal Variations in Nitrate Contamination
- Pre-Monsoon Levels: 30.77% of groundwater samples contaminated.
- Post-Monsoon Levels: Contamination rises to 32.66%, attributed to rainfall leaching nitrates from agricultural fields into aquifers.
Other Contaminants in Groundwater
- Fluoride:
- High concentrations reported in Rajasthan, Haryana, and Karnataka.
- Linked to skeletal and dental fluorosis.
- Uranium:
- Concentrations exceeding 100 ppb observed in Rajasthan and Punjab, raising severe health concerns.
- Impact: These contaminants add to the groundwater crisis, emphasizing the need for comprehensive management.
Groundwater Extraction Trends
- Current Extraction Rate: 60.4% (unchanged since 2009).
- Improvement in ‘Safe’ Blocks:
- 2022: 67.4% of blocks categorized as safe.
- 2024: Increased to 73%, indicating slight progress.
- Challenges: Reduction in the total number of blocks analyzed by 343 raises concerns about the reliability of this improvement.
Health Implications of Nitrate Contamination
- Nitrate Above 45 mg/L:
- Converts to nitrite in the human body, causing conditions like methemoglobinemia (blue baby syndrome) in infants.
- Linked to increased risk of certain cancers and other chronic illnesses.
- Fluoride and Uranium:
- Long-term exposure results in severe health problems, including kidney issues and bone deformities.
Strategies to Address Groundwater Contamination
- Sustainable Agricultural Practices:
- Minimize nitrogenous fertilizer use.
- Promote organic farming and alternative fertilizers.
- Improved Water Management:
- Recharge groundwater with treated water.
- Implement rainwater harvesting.
- Regular Monitoring:
- Expand the scope of groundwater quality testing.
- Utilize real-time monitoring systems for early detection.
- Public Awareness:
- Educate farmers and communities on the dangers of over-fertilization.
- Encourage water conservation and pollution mitigation practices.
- Policy Interventions:
- Enforce stricter regulations on fertilizer usage.
- Support technological innovation in water purification and contamination prevention.
Conclusion
The growing groundwater contamination in India highlights an urgent need for coordinated efforts to protect this vital resource. While progress has been made in some areas, the rising nitrate levels in 56% of districts and the presence of other toxic contaminants demand immediate attention. Sustainable practices, advanced monitoring, and proactive policies are essential to safeguarding public health and ensuring water security for future generations.
Also Read: ISRO to Launch US Communication Satellite “Bluebird”
Disclaimer
This article is for educational purposes, focusing on the relevance of the topic for UPSC aspirants. Students should stay updated on further developments and refer to official sources for comprehensive preparation.
Follow Fusion IAS