Annual Groundwater Quality Report 2025

Annual Groundwater Quality Report 2025

• The Central Ground Water Board (CGWB) has released the Annual Groundwater Quality Report 2025.
• The report presents both encouraging trends and areas of significant concern related to chemical and geogenic contaminants.

Overall Groundwater Quality Status

• 71.7% of India’s groundwater samples meet Bureau of Indian Standards (BIS) drinking-water specifications.
• Conversely, 28.3% of samples exceed permissible limits for one or more parameters, reflecting contamination risks across several regions.

Major Groundwater Contaminants

1. Nitrate – The Most Widespread Pollutant

• Around 20% of samples show nitrate levels above the WHO/BIS limit of 45 mg/L.
• Primary sources:
  o Excessive fertilizer application
  o Leakage from sewage systems
  o Animal waste infiltration
• Nitrate contamination is predominantly anthropogenic (human-caused).

1. Fluoride Contamination

• 8.05% of samples exceed acceptable fluoride levels.
• Contamination is primarily geogenic (naturally occurring), especially in groundwater extracted from deeper aquifers.
• Rajasthan records the highest fluoride concentrations nationwide.

1. Uranium Contamination

• Samples above the safe limit of 30 ppb were found in:
  o 6.71% during Pre-Monsoon
  o 7.91% during Post-Monsoon
• Highest levels reported in:
  o Punjab (most affected)
  o Haryana
  o Delhi

1. Salinity (Electrical Conductivity – EC)

• 7.23% of samples in arid/semi-arid regions such as Rajasthan and Delhi show elevated salinity.
• High EC affects both drinking suitability and long-term soil health.

1. Lead Contamination

• Delhi shows the most significant lead presence in groundwater.
• Health impacts of lead include:
  o Cognitive impairment
  o Elevated blood pressure
  o Kidney dysfunction
  o Classified as a probable carcinogen

1. Other Trace Metals and Geogenic Issues

• Arsenic contamination is prevalent particularly in the Ganga and Brahmaputra basins.
• Manganese contamination is noted in:
  o Assam
  o Karnataka
  o Odisha
  o Uttar Pradesh
  o West Bengal

Groundwater for Irrigation
Despite drinking-water concerns, groundwater remains largely suitable for agricultural use.

• 94.30% of samples fall under the “excellent” category for irrigation suitability, indicating low salinity hazards for crops in most regions.

About the Central Ground Water Board (CGWB)

• Headquarters: Faridabad, Haryana
• Established: 1970 (formerly the Exploratory Tube Wells Organization)
• Ministry: Operates under the Ministry of Jal Shakti
  Functions of CGWB
• Groundwater exploration, assessment, monitoring, and management
• Advising states on groundwater conservation
• Undertaking hydrogeological surveys
• Regulating groundwater development and usage
• Also functions as the Central Ground Water Authority (CGWA), constituted under the Environment Protection Act, 1986