Water pollution in India: A comprehensive overview

Water is the lifeline of human existence, sustaining agriculture, industry, households, and natural ecosystems alike. Yet across India, pollution has turned this essential resource into a growing threat. The Central Pollution Control Board (CPCB) reports that more than 350 river stretches in the country are polluted, impacting both rural and urban communities. The consequences are severe—millions fall ill each year from waterborne diseases, while aquatic ecosystems are losing biodiversity at alarming rates, endangering the balance of life that water once sustained.

What is Water Pollution?

Water pollution occurs when harmful substances—chemicals, microorganisms, plastics, or waste—contaminate rivers, lakes, groundwater, or seas, degrading their quality. (Source: 

Key indicators of water pollution in India include:

• Biochemical Oxygen Demand (BOD) – shows organic load.
  

• Dissolved Oxygen (DO) – critical for aquatic organisms.

• Faecal Coliform (FC) – indicator of sewage contamination.

Why is it a Critical Issue in India?

Population pressure: Rapid urbanisation has increased sewage generation beyond treatment capacity.

• Industrialisation: Effluents from industries often bypass treatment norms.
  

• Agricultural runoff: Fertilisers and pesticides leach into rivers and groundwater.
  

• Cultural/religious practices: Idol immersion, ritual bathing, and cremation add waste load to rivers.
  

IWP’s Sewage will overtake agriculture highlights how untreated sewage is projected to surpass agricultural runoff as the biggest river polluter.

Why is it a Critical Issue in India?

• Population pressure: Rapid urbanisation has increased sewage generation beyond treatment capacity.
  

• Industrialisation: Effluents from industries often bypass treatment norms.
  

• Agricultural runoff: Fertilisers and pesticides leach into rivers and groundwater.
  

• Cultural/religious practices: Idol immersion, ritual bathing, and cremation add waste load to rivers.

IWP’s Sewage will overtake agriculture highlights how untreated sewage is projected to surpass agricultural runoff as the biggest river polluter.

Types & Causes of Water Pollution in India

Surface water pollution: Rivers, lakes, and ponds contaminated by sewage, industrial effluents, and agricultural runoff.

Groundwater pollution: Nitrate contamination, heavy metals, and naturally occurring arsenic and fluoride.

Major contributors:

• Domestic sewage (80% untreated).
  

• Industrial effluents (tanneries, textiles, paper mills).
  

• Agriculture (fertilisers, pesticides).
  

• Mining & thermal plants (acid drainage, fly ash).
  

• Religious activities (immersion, offerings).

The article From pollution to solutions provides an overview of these interconnected drivers.

River Water Pollution in India

India’s rivers are the most visible victims of water pollution.

Top 10 Most Polluted Rivers – Data Snapshot

Notes on Data & Classification

• The CPCB (Central Pollution Control Board) identifies polluted river stretches (PRS) under 5 priority categories based on Biochemical Oxygen Demand (BOD) and Dissolved Oxygen (DO) levels.
  
  

• Data compiled here is from CPCB’s “River Stretches for Restoration” (2022) and verified with state pollution boards (SPCB) and media reports citing CPCB/NMCG data (2021–2024).
  
  

• Rivers like Cooum, Sabarmati, Yamuna, and Bahela repeatedly feature in Priority-I lists due to very high BOD and faecal contamination.

References (Publicly Accessible)

 CPCB Report on Identified Polluted River Stretches, 2022

DT Next, “Cooum most polluted river in India: CPCB Report” (Jan 2023)

Times of India, “Sabarmati second most polluted river in India” (Feb 2023)

Indian Express, “Yamuna stretch in Delhi continues to be among the most polluted” (2023)

MPCB–CPCB Joint Report on Mithi River, 2022

1) Down To Earth, “Musi River pollution: A challenge for Hyderabad’s health” (2023)

2) NMCG Annual Report 2023

Water Quality in India

Standards: BIS IS 10500 (drinking water), WHO guidelines, CPCB monitoring.

Water Quality Index (WQI): Used to assess overall river health.

Urban vs. Rural: Urban water faces sewage/chemical load; rural groundwater is affected by fluoride, arsenic, and nitrates.

Water Pollution Statistics in India

River stretches: 351 polluted across 323 rivers (CPCB).

Sewage: 72,368 MLD generated, ~44% treated (CPCB 2021).

Groundwater: Arsenic affects 10 states; fluoride 20 states.

Health: WHO estimates 21% of communicable diseases in India are water-related.

IWP’sFrom pollution to solutions highlights the sewage treatment gap as the biggest pollution driver.

Impact of Water Pollution

Human Health

Waterborne diseases remain a significant public health challenge in India. Annually, approximately 37.7 million Indians are affected by waterborne diseases, with 1.5 million children succumbing to diarrheal illnesses alone. The economic burden of these diseases is substantial, with an estimated loss of 73 million working days, translating to a financial loss of around $600 million each year. Diseases such as cholera, acute diarrheal diseases, typhoid, and viral hepatitis have collectively caused over 10,000 deaths in the past five years. The primary culprits are high levels of biological contamination in water sources, including viruses, bacteria, and protozoa, often originating from untreated sewage, industrial effluents, and agricultural runoff (WHO, 2022).

Agriculture

Polluted water used for irrigation poses severe risks to agriculture. The introduction of heavy metals and toxic chemicals into the soil can degrade soil quality, reduce crop yields, and contaminate the food chain. The accumulation of these pollutants in crops can lead to health hazards for consumers and economic losses for farmers. Moreover, salinization of water bodies due to pollution affects freshwater availability for irrigation, further exacerbating food security issues (IWP, 2023).

Biodiversity

Water pollution leads to eutrophication, a process where excessive nutrients, particularly nitrogen and phosphorus, promote the overgrowth of algae in water bodies. This algal bloom depletes oxygen levels, leading to the untimely death of fish and the creation of "dead zones" where aquatic life cannot survive. Such ecological imbalances disrupt aquatic ecosystems, endanger species diversity, and affect the livelihoods of communities dependent on fishing (IWP, 2023).

Economy

The economic repercussions of water pollution are profound. The World Bank estimates that water pollution costs India approximately 3% of its GDP annually. This loss stems from healthcare expenses, reduced agricultural productivity, and the decline in fisheries and tourism. Additionally, the contamination of water sources necessitates significant investments in water treatment infrastructure, further straining public finances (World Bank, 2017).

Government Policies & Initiatives

Legislation

India has enacted several legislative measures to combat water pollution:

• Water (Prevention and Control of Pollution) Act, 1974: Established the Central Pollution Control Board (CPCB) and State Pollution Control Boards (SPCBs), granting them authority to regulate and control water pollution (IWP, 2023).
  
  

• Environment Protection Act, 1986: Provides a framework for environmental protection, including water bodies.
  
  

• National Water Policy, 2012: Outlines sustainable water resource management and emphasises pollution control.

Flagship Programs

The Indian government has launched several initiatives aimed at addressing water pollution:

• Namami Gange Programme: Integrated river conservation mission launched in 2014 to rejuvenate the Ganga and its tributaries through sewage treatment, riverfront development, and afforestation efforts (IWP, 2023).
  

• National River Conservation Plan (NRCP): Improves water quality through sewage treatment plants and interception and diversion of sewage.
  

• CPCB and SPCBs: Monitor and enforce environmental standards to control water pollution.

Judicial Oversight

The judiciary plays a crucial role in enforcing environmental laws:

• National Green Tribunal (NGT): Handles environmental disputes and has issued directives for cleaning rivers and regulating industrial effluents (IWP, 2023).

• Supreme Court Orders: Intervenes in severe water pollution cases, issuing orders for the closure of polluting industries and implementation of pollution control measures.

Solutions And Mitigation Measures

Sewage treatment: centralised + decentralised STPs; reuse treated water.

Case Study: Bengaluru's Decentralised STPs

Bengaluru has implemented a significant number of decentralised sewage treatment plants (STPs), particularly in the Yelahanka zone. These systems treat wastewater at the source, reducing the burden on centralised infrastructure and promoting water reuse within local communities. A survey by WELL Labs and Eawag highlighted the effectiveness of these systems in managing urban wastewater and their potential for scaling in similar urban settings WELL LABS.

Case Study: Delawas STP, Jaipur

The Delawas Sewage Treatment Plant in Jaipur serves as an example of a centralised system that efficiently manages sewage from surrounding areas. The plant employs gravity flow to transport sewage, minimising energy consumption and operational costs. This approach aligns with sustainable practices in urban wastewater management research atResearchGate.

Industrial compliance: real-time effluent monitoring, ZLD enforcement.

Case Study: Real-Time Monitoring in Ganga River Basin

In the Ganga river basin, real-time water quality monitoring systems have been deployed to track pollution levels and identify industrial discharges. These systems enhance transparency and accountability, supporting enforcement of environmental regulations and promoting compliance among industries aaxisnano.

Case Study: Continuous Emission Monitoring Systems (CEMS)

The Central Pollution Control Board (CPCB) has mandated the installation of Continuous Emission Monitoring Systems (CEMS) in various industries across India. These systems provide real-time data on pollutants, enabling regulatory bodies to monitor compliance and take timely actions against violators ScienceDirect.

Community initiatives: citizen-led river cleaning, water quality monitoring.

Case Study: Earth5R's Mithi River Cleanup Model

Earth5R has pioneered a community-driven model for cleaning the Mithi River in Mumbai. By mobilising local residents, students, and volunteers, the initiative has successfully removed significant amounts of waste from the river, raising awareness about sustainable waste management and fostering a sense of ownership among the community Medium.

Case Study: Go For Gomti's Cleanup and Reading Sessions

In Lucknow, the Go For Gomti initiative combines environmental action with cultural enrichment. Volunteers regularly clean the Gomti River and engage in community reading sessions, promoting both ecological sustainability and literacyThe Times of India.

Rainwater harvesting & recharge.

Case Study: Chennai's Rooftop Rainwater Harvesting

Chennai has implemented rooftop rainwater harvesting systems in educational institutions, such as St Peter’s Engineering College. These systems have enhanced groundwater recharge, ensuring a sustainable water supply for the campus and serving as a model for other institutions SRS Journal.

Case Study: Thotli Micro-Watershed, Kolar District

In the Thotli micro-watershed of Kolar district, the construction of water harvesting structures has significantly augmented groundwater recharge. This initiative has improved water availability for agriculture and domestic use, demonstrating the effectiveness of watershed-based rainwater harvestingdr.lib.iastate.edu.

Sustainable agriculture: organic inputs, controlled fertiliser use.

The CSIR-National Environmental Engineering Research Institute (CSIR-NEERI) has developed a Faecal Sludge and Septage Management (FSSM) plant in Chandrapur. The plant treats faecal waste and converts it into organic manure, promoting sustainable agricultural practices and reducing reliance on chemical fertilisers. The Times of India.

Nature-based solutions: Constructed wetlands and the Lake Revive Tool for lake restoration.

Case Study: Constructed Wetlands for Wastewater Treatment

Constructed wetlands have been implemented in various parts of India as nature-based solutions for wastewater treatment. These systems utilize natural processes to treat sewage, offering a cost-effective and environmentally friendly alternative to conventional treatment methods. Frontiers.

Case Study: Lake Revive Tool for Lake Restoration

The Lake Revive Tool is an initiative aimed at restoring urban lakes through community engagement and scientific interventions. By addressing pollution sources and promoting sustainable management practices, the tool has contributed to the rejuvenation of several lakes in India Earth5R.

Also seeFinding scalable and financially viable water solutions for innovative water startups.

Recent News & Case Studies

Yamuna, Delhi: faecal coliform levels in millions of MPN/100 mL (CPCB 2025).
Sabarmati, Ahmedabad: BOD reached 292 mg/L (CPCB 2023); “Sabarmati clean-up complete, 945 tonnes of waste removed” (Times of India, 2025)
Musi, Hyderabad: 90% of the river flow has changed to sewage; see IWP’s From lifeline to drain.
Emerging pollutants: IWP’s Drugged and poisoned highlights pharmaceutical contamination.
Plastics: IWP’s Plastic siege explains the rising threat of microplastics.
Local interventions: IWP’s Preventing contamination of river Danro shows grassroots efforts in Jharkhand.

Frequently Asked Questions (FAQs) – Water Pollution in India

References

India Water Portal Articles

1. From pollution to solutions
   

2. Water Can Kill
   

3. Growing Challenge of Water Contamination
   

4. Drugged and Poisoned
   

5. From Lifeline to Drain
   

6. India’s Efforts at Water Pollution Control
   

7. Lake Revive Tool
   

8. Plastic Siege
   

9. Preventing Contamination of River Danro
   

External / Government References

1. Central Pollution Control Board (CPCB), National Inventory of Sewage Treatment Plants, 2021 – https://pib.gov.in/Pressreleaseshare.aspx?PRID=1779784
   

2. CPCB, National Water Quality Monitoring Program – https://cpcb.nic.in/wqm/
   

3. WHO, Guidelines for Drinking Water Quality, 2017 – https://www.who.int/publications/i/item/9789241549950
   

DowntoEarth, 351 Polluted River Stretches in India – 2018 –https://www.downtoearth.org.in/water/351-polluted-river-stretches-in-india-a-list-across-states-78083