GPIs are defined as industries that discharge more than 100 000 L of wastewater and/or hazardous chemicals into rivers or water bodies. The different types of GPIs are pulp and paper mills, distilleries, sugar mills, textile units, tanneries, thermal power plants, food, dairy, and beverage industries, chemical units, slaughterhouses, etc. As a result of this, the freshwater that Indian rivers carry is now so severely polluted that rivers threaten the very life they once nurtured. There are 992 GPIs in the river Ganga and its tributaries, i.e. Kali and Ramganga, and, from these, 851 industrial units are found in Uttar Pradesh, 61 in Uttarakhand, 43 in West Bengal, and 40 in Bihar (www.downtoearth.org.in/news/pollution/faith‐to‐filth‐thanks‐to‐kumbh‐prayagraj‐sinks‐in‐solid‐waste‐64579). The major water pollution contributors in Kosi, Ramganga, and Kali river catchments are tanneries, sugar and distilleries, and pulp and paper units. Panigrahi and Pattnaik (2017) in their report mentioned that the Gomati River near Lucknow urban center is mostly polluted by heavy metals. Malik et al. (2014) mentioned that many industries are situated near the bank of the Yamuna River, therefore, it is considered the most polluted river in India. Ahirwar et al. (2015) state the major cause of water pollution in the River Son is due to effluents discharged from thermal power plants and pulp and paper industries. Therefore, it can be said that water body pollution due to industrial discharge affects the food web and hampers public health (Ahirwar et al. 2015). It becomes crucially important to access and control the quality of water bodies by proper treatment of the wastewater at the source itself before directly discharging it to the environment (Bharti et al. 2013).
This chapter examines the major contributing wastewater industries, their present status, and the major pollutants released from different types of industries situated in India. The impact of pollutant discharge from these industries into rivers, drains, and so on, are also discussed in detail. The current status and quality of rivers including the River Ganga and its tributaries, Yamuna, Cauvery, Narmada, and Bandi are also highlighted. The role of different legal authorities and monitoring bodies to control the water pollution caused by industries and their rules, regulations, and drawbacks are explained in the last section of the chapter.
3.2 Industrialization in India
Over the last century, industrial production in India has risen more than 50‐fold. India has made rapid industrialization strides and is one of the world's ten most developing nations. However, poor monitoring and control of emissions combined with unplanned growth have resulted in significant harm to the environment.
Industrialization is the period of social and economic transition that transforms a human civilization from an agrarian community into an industrial culture, including the comprehensive rearrangement of an economy into an industrial culture (Bhandari and Garg 2015). Industrialization in a country leads to increases in urbanization, extraction of natural resources, industrial growth, and environmental pollution, and a decrease in environmental suitability.
Industrialization is on the expansion as is environmental pollution because of emissions and waste produced from these industries. Industrial pollution because of its higher production can possibly cause irreversible responses in nature and henceforth represents a significant risk to sustainable development (Baek et al. 2009).
3.3 Categorization of Industries
The Central Pollution Board (CPCB) listed 17 groups of the most polluting industrial sectors that contribute to environmental degradation in terms of particulate matter, gases, and effluents. Currently, 77% of industries contribute to water pollution, while 15% contribute to air pollution and the remaining 8% to air and water contamination (Annual Report 2004–2009).
The industries that rely on natural resources are the most polluting and are rising rapidly. Depending upon the pollution load generated and the water extracted by industries, they are classified into three major groups: (i) major water‐intensive industries, including tanneries, slaughterhouses, pulp and paper, textile, breweries and soft drinks, etc.; (ii) moderate water‐consuming industries, including canning industries, roller and flour mills, and food products; (iii) industries using water for sanitation, including electrical and electronic industries, woods, rubber, glass, wax, paint, and plastic (http://14.139.116.20:8080/jspui/bitstream/10603/33831/4/chapter4.pdf).
The Government of India, Ministry of Environment Forestry and Climate Change (MoEFCC) classifies all industries as red, orange, and green based on their ability to cause pollution: red –high polluting; orange – less polluting; and green – nonpolluting industries. The MoEFCC has developed industrial sector categorization criteria based on the Pollution Index which is a feature of emissions (air pollutants), effluents (water pollutants), produced hazardous waste, and resource consumption. They are classified as follows (MOI 2019).
Industrial sectors having a Pollution Index score of 60 and above – red category
Industrial sectors having a Pollution Index score of 41–59 – orange category
Industrial sectors having a Pollution Index score of 21–40 – green category
Industrial sectors having a Pollution Index score ≤20 – white category
3.4 Criteria for Determination of Grossly Polluting Industries
GPIs are classified as effluent discharging industries into a waterway and (i) handling hazardous substances, (ii) effluent with a BOD load of 100 kg per day or more, or (iii) a combination of (i) and (ii) according to the CPCB Annual Report (2004–2009).
According to the latest data from 36 states/UTs obtained by the CPCB, 2743 industries have been listed as GPIs for routine monitoring by CPCB/SPCBs/PCCs. Of those, 2497 units are still in service and 246 units have been closed by themselves. Of the operating units, it is stated that 2222 units comply with environmental standards. There has been a 136% increase in the number of GPIs. In 2011, only 22 states/UTs were covered to identify industries, whereas, in 2019, the data received belonged to 36 states, this implies that there has been increased industrialization/development over this time in India. Also, compliance status (based on discharge limit parameters and the validity of consent letters) increased to 89% in 2018 – it was only 79.8% in 2011 (Groundwater Year Book – India 2018–2019).
3.4.1 State Distribution of Grossly Polluting Industries in India
The graph shown in Figure 3.1 represents the state presentation of GPIs in India in 2019. Table 3.1 depicts four major states comprising a large number of GPIs as per the CPCB report 2019.
The study of state and category distribution shows that the states of Maharashtra, Uttar Pradesh, Gujarat, Andhra Pradesh, and Tamil Nadu have significantly large numbers of industries in the sectors previously listed and that the tannery, textile, and sugar sectors have the maximum number of industries, followed by pharmaceuticals, distillery, cement, and fertilizer. It also indicates that agro‐based and chemical industries have major shares of 47% and 37%, respectively, of the total number of industries. Table 3.1 shows that Uttar Pradesh comprises nearly 43.7% of GPIs in India followed by Haryana, Gujarat, and Andhra Pradesh.