Why in news?
The Central Pollution Control Board (CPCB) released its 2023 assessment of India’s river water quality in September 2025. The report noted a slight reduction in the number of polluted sites compared with the previous year, but it also highlighted persistent stretches where organic pollution remains high.
Historical context
The CPCB began monitoring river pollution in the 1970s using indicators such as Biological Oxygen Demand (BOD), which reflects the amount of organic matter in water. High BOD means that aquatic life will be starved of oxygen. Programmes like the Ganga Action Plan (1985), National River Conservation Plan and Namami Gange sought to clean rivers but have had mixed success. Since 2018 the CPCB has categorised stretches into priorities based on BOD levels: priority‑1 (> 30 mg/L) to priority‑5 (3–6 mg/L).
Key findings of the 2023 report
- Overall improvement: Polluted monitoring locations fell to 807, down from 815 in 2022. Polluted river stretches declined from 311 to 296.
- Priority‑1 reduction: The number of critically polluted stretches (BOD > 30 mg/L) decreased from 45 to 37, showing targeted interventions are working.
- State distribution: Maharashtra, Kerala, Madhya Pradesh and Manipur have the highest numbers of polluted sites. Some northeastern states showed improvement, while new hotspots emerged in hill states.
- Monitoring network: The CPCB and state agencies operate around 4,700 monitoring stations across major rivers to collect data.
Significance and next steps
- Expand sewage treatment: Most pollution comes from untreated municipal sewage. Building and operating adequate treatment plants is essential.
- Industrial compliance: Enforcement of discharge standards and adoption of zero‑liquid‑discharge technologies will reduce effluent load.
- River‑basin approach: Managing rivers as entire basins rather than state‑wise segments can lead to integrated solutions and equitable sharing.
- Community participation: Local groups, farmers and industries should be involved in pollution control through awareness and co‑financing.
- Continuous monitoring: Real‑time sensors and public reporting of data can create transparency and prompt action.
Improving water quality is a long‑term task. The latest CPCB report signals progress but also reminds policymakers that cleaner rivers require sustained investment and cooperation across sectors and states.