Water Pollution In India: Understanding Dual Sources

Water pollution is a pressing issue in India, with far-reaching consequences for the environment, public health, and the economy. The two main sources of water pollution in India are untreated sewage and agricultural runoff, which contaminate water sources with harmful substances, making them unfit for human use and detrimental to aquatic life. India's rapid industrialization and urbanization have resulted in insufficient wastewater treatment infrastructure, leading to the discharge of untreated sewage into water bodies. Additionally, agricultural activities, such as the use of pesticides and fertilizers, contribute to water pollution through runoff into nearby water sources. These two sources of pollution have severe impacts on water quality, biodiversity, and the health of those exposed to contaminated water.

Untreated sewage and industrial discharge

Untreated Sewage

The discharge of untreated sewage from cities, towns, and villages is the predominant cause of water pollution in India. The gap between sewage generation and treatment capacity is significant. Major cities produce 38,354 million litres of sewage per day, while the urban sewage treatment capacity is only 11,786 million litres per day. This disparity results in the discharge of untreated domestic wastewater, which severely pollutes water bodies.

The analysis of water samples from 1995 to 2008 revealed severe organic and bacterial contamination in India's water bodies due to untreated sewage. This contamination poses health risks, as waterborne pathogens can cause diseases such as cholera, typhoid, and hepatitis. Additionally, the intensive cultivation of vegetables irrigated with raw sewage has emerged as a major health concern, especially for those consumed uncooked.

The lack of proper sewage treatment is attributed to insufficient treatment capacity and poorly maintained or non-operational sewage treatment plants. As a result, wastewater percolates into the soil or evaporates, leading to unhygienic conditions and the release of pollutants into surface and groundwater.

Industrial Discharge

Industrial discharge is another major source of water pollution in India. The release of untreated and partially treated industrial effluents, including hazardous wastes, contributes significantly to river pollution. A Central Pollution Control Board (CPCB) report identified 351 polluted river stretches on 323 rivers, with industrial discharge being the primary culprit.

Industrial activities generate various contaminants, including heavy metals, pesticides, fungicides, and industrial chemicals. These pollutants harm aquatic ecosystems, disrupt their balance, lead to the decline of fish and other aquatic organisms, cause habitat degradation, and affect drinking water sources.

To address industrial pollution, the CPCB has developed Standard Operating Procedures (SoPs) to enable waste processing industries to handle hazardous wastes properly. Additionally, the government has made available common hazardous waste treatment, storage, and disposal facilities in 18 states and union territories.

Agricultural runoff

Agricultural activities, such as the use of chemical fertilizers and pesticides, contribute to water pollution when these substances are washed off the fields during flood flows or seep into water bodies through drainage and groundwater. While the application of agricultural chemicals in India is lower than in developed countries, the intensive nature of modern farming practices has led to increased diffuse agricultural pollution. This type of pollution is challenging to control with traditional methods such as discharge permits or environmental audits.

The impact of agricultural runoff on water quality has severe implications. Firstly, it contaminates water sources, making them unfit for human consumption and harmful to aquatic life. Pesticides and fertilizers, when washed into rivers and lakes, can lead to eutrophication, causing excessive nutrient levels that disrupt aquatic ecosystems. This, in turn, leads to a decline in fish populations, loss of biodiversity, and degradation of habitats.

Secondly, agricultural runoff affects soil fertility, reducing crop yields and impacting food security in India. It also has economic repercussions, including healthcare costs for treating waterborne diseases, loss of livelihoods for fishing communities, and expenses for water treatment and purification technologies.

Additionally, agricultural runoff contributes to groundwater contamination, affecting millions of people who rely on groundwater as their primary source of drinking water. High levels of contaminants, such as arsenic and fluoride, have been detected in various parts of India, posing severe health risks to the population.

To address the issue of agricultural runoff, India has undertaken several initiatives, including the Ganga rejuvenation efforts by the union government and the Yamuna clean-up. These efforts aim to improve water quality and mitigate the detrimental effects of agricultural runoff on the environment and public health.

Atmospheric deposition

Industrial Emissions

Industrial discharge is a major source of water pollution in India. The country's booming industrialisation has led to an increase in air pollutant emissions, with coal-based thermal power plants being a key contributor. These plants release pollutants such as sulphur dioxide (SO2) and nitrogen oxides (NOx), which can lead to acid rain. Acid rain has already been reported in some parts of India, and it is expected to increase in the future. The oxidation and wet deposition of SO2 and NOx emissions result in acid rain, which has harmful effects on biodiversity.

Vehicular Pollution

The rise in private vehicles, particularly in urban areas, is another significant factor in atmospheric deposition. Vehicle exhausts release pollutants such as nitrogen dioxide (NO2) and particulate matter, which have detrimental effects on both human health and the environment. Studies have shown that emissions from vehicles can significantly impact the health of plants and trees within close proximity to roadways.

Urbanisation

The increasing urbanisation in India, particularly in cities like Delhi, has led to higher levels of atmospheric dust and chemical constituents in the air. The rapid expansion of road lengths, the growing number of vehicles, and the increase in industrial units have all contributed to the rise in atmospheric deposition. This has resulted in carbon-rich dust interacting with atmospheric pollutants, which has significant implications for human health, global warming, and climate change.

Impact on Water Sources

The atmospheric deposition of pollutants has severe consequences for water sources in India. As these pollutants are deposited back to the earth, they can contaminate water bodies, making them unfit for human use and harmful to aquatic life. This contamination can occur when pollutants are deposited directly onto water surfaces or when they are deposited on land and subsequently washed into water bodies through runoff. Atmospheric deposition can also contribute to the pollution of groundwater sources, which are crucial for drinking water and irrigation.

Oil spills

In December 2023, an oil spill occurred at the Chennai Petroleum Corporation Limited (CPCL) in the Ennore-Manali area, a hub for petrochemical and other heavy industries. The spill was exacerbated by floods following Cyclone Michaung, causing the oil to spread into the Buckingham Canal and Ennore Creek. This incident highlights the vulnerability of coastal areas like Ennore-Manali to environmental disasters, as annual flooding can increase the severity of oil spills and other chemical leaks.

The Ennore-Manali oil spill had devastating consequences for the local ecosystem, threatening the livelihoods and health of thousands of fishermen. The oil entered residential areas, exposing residents to hazardous substances, including volatile organic compounds and polycyclic aromatic hydrocarbons, which were found to be alarmingly above permissible limits. This situation underscores the urgent need for stronger regulatory frameworks and proactive measures to prevent and mitigate the impact of oil spills in India.

Oil Spill India (OSI), an international conference and exhibition, has played a pivotal role in bringing together stakeholders from various sectors to address the challenges posed by oil spills. The forum facilitates the exchange of knowledge, best practices, and global experiences in oil spill prevention, preparedness, response, and restoration. OSI has been instrumental in raising awareness, fostering collaboration, and driving discussions on mitigating the risk of oil spills in India.

To summarize, oil spills in India have severe environmental, health, and economic repercussions. The Ennore-Manali oil spill exemplifies the destructive nature of such incidents and underscores the urgency for enhanced regulations and proactive measures. Oil Spill India conferences have been crucial in addressing these challenges, promoting awareness, and uniting stakeholders to work towards preventing and effectively managing oil spills.

Ineffective wastewater treatment

India's water pollution crisis is a complex issue with far-reaching consequences for the environment, public health, and the economy. One of the key contributors to this crisis is the ineffective treatment of wastewater. This problem is twofold: India lacks sufficient wastewater treatment capacity, and the treatment plants that do exist often suffer from operational and maintenance issues.

Firstly, there is a significant gap between the amount of wastewater generated and the capacity to treat it. Major Indian cities produce an estimated 38,354 million litres of sewage per day, yet the urban sewage treatment capacity can only handle about 11,786 million litres. This disparity results in a large volume of untreated sewage being discharged into water bodies, primarily from urban centres. This untreated domestic sewage is the predominant cause of water pollution in India, severely affecting many Indian rivers.

The inadequate treatment capacity is attributed to a lack of infrastructure, funding, and awareness. India's rapidly growing population, intensive agriculture, and climate change impacts further exacerbate the problem, driving water scarcity and increasing the demand for effective wastewater treatment. However, the development of low-cost, innovative technologies to meet current discharge standards remains a critical challenge.

Secondly, the existing sewage treatment plants in India face several challenges that hinder their effectiveness. Operational issues include improper design, poor maintenance, unreliable electricity supply, absentee employees, and poor management. As a result, most government-owned treatment plants remain closed or underutilised. This situation allows untreated wastewater to percolate into the soil or evaporate, leading to groundwater contamination and the release of pollutants into surface water sources.

The consequences of ineffective wastewater treatment are far-reaching. Contaminated water sources pose significant health risks, causing waterborne diseases such as cholera, typhoid, and hepatitis. Additionally, pollutants like heavy metals, pesticides, and industrial chemicals harm aquatic ecosystems, leading to biodiversity loss and habitat degradation. The economic impacts are also substantial, including healthcare costs, loss of livelihoods for fishing communities, and expenses for water treatment and purification.

Addressing the issue of ineffective wastewater treatment in India requires a multifaceted approach. Improving infrastructure, investing in research and development for low-cost treatment technologies, and ensuring proper maintenance and operation of treatment plants are crucial steps. Additionally, implementing policies and regulations for efficient wastewater management, such as the Water (Prevention and Control of Pollution) Act, 1974, is essential. By bridging the gap between wastewater generation and treatment capacity and ensuring the effective operation of treatment plants, India can make significant strides towards mitigating its water pollution crisis.

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