Pollution of the river Ganga has dangerous effects on human health and the environment, as it is the largest river of the country and supports 40% of the total population of India. It is severely polluted with the industrial contaminants and human excretions. It is one of the most sacred rivers for the Hindus and a lifeline to a billion of people who live along its course. Kanpur is one of the populated cities located along its course and it supplies tonnes of toxic waste to the river on a daily basis. Leather tanneries are the major source of such wastes and effluents to the river. The petitioner, M.C. Mehta filed a writ petition to prevent such tanneries from disposing off industrial wastes and effluents in the river or to issue any direction, which mandates them incorporate certain treatment plants for the treatment of such toxic effluents before disposing off. 

The leather tanneries are polluting the Holy River, which is even a source for drinking water in many households. Toxic wastes and effluents disposed of by them are not treated and hence this results in water pollution of most sacred rivers of the country.

The court highlighted the importance of certain provisions such as Article 48A, 51A. Article 48-A states that the State shall endeavor to improve and protect the environment and to preserve the forests and wildlife of the country. Article 51-A of the Constitution of India, imposes a fundamental duty on every citizen to improve and protect the natural environment including forests, lakes, rivers and wildlife.

The bench also stated the importance of Water (Prevention and Control of Pollution) Act, 1974. Section 24 of the Act prohibits the use of any ‘stream’ for the purpose of disposing the polluting matter.

The court also relied on the Environment (Protection) Act, 1986. Section 3 of this Act discusses the powers of the Central Government to take effective and appropriate steps for the protection and improving the quality of the environment and preventing environmental pollution.

The respondents mentioned that the tanneries discharge trade effluents, which leads to sewage, which further leads to the Municipal Sewage Plant before they are thrown into the river. It was not argued by any of the tanneries that the water in the river was polluted by the effluents discharged by them. Some tanneries had already set up the effluent treatment plants and some were engaged in the construction of the primary treatment plants. However, the respondents argued that it would not be possible for them to have the secondary system for treating wastewater, as that would involve enormous expenditure, which the tanneries themselves would not be able to meet.

The court held that besides the provisions of the Water Act, no effective steps were taken by the government to prevent the factories from discharging the effluents into the river. The court directed the tanneries to establish a primary treatment plant. The Court further said that the financial capability of the tanneries should be considered as irrelevant while obliging them to establish a primary treatment plant.