Chapter General 1.1 INTRODUCTION What is Pure Water? What is Polluted Water?

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1 Chapter 1 General 1.1 INTRODUCTION Water is one of the most important commodities which Man has exploited than any other resource for sustenance of his life. Most of the water on this planet is stored in oceans and ice caps which is difficult to be recovered for our diverse needs. Most of our demand for water is fulfilled by rain water which gets deposited in surface and ground water resources. The quantity of this utilizable water is very much limited on the earth. Though, water is continuously purified by evaporation and precipitation, yet pollution of water has emerged as one of the most significant environmental problems of the recent times. Not only there is an increasing concern for rapidly deteriorating supply of water but the quantity of utilizable water is also fast diminishing. The causes of such a situation may be many, but gross pollution of water has its origin mainly in urbanization, industrialization, agriculture and increase in human population observed in past one and a half century. What is Pure Water? It can be said that no water is pure or clean owing to the presence of some quantities of gases, minerals and life. However, for all practical purposes, a pure water is considered to be that which has low dissolved and suspended solids and obnoxious gases as well as low in biological life. Such a high quality of water may be required only for the drinking purposes, while for other uses like agriculture and industry, the quality of water can be quite flexible and water polluted up to certain extent, in general sense, can be regarded as pure. What is Polluted Water? The unique properties of water which make it universal solvent and a renewable resource also make it a substance which by virtue of these properties has got a much greater tendency to get polluted. Water can be regarded polluted when it gets changed in its quality or composition either naturally or as a result of human activities so as to become less suitable for drinking, domestic, agricultural, industrial, recreational, wildlife and other uses for which it would have been otherwise suitable in its natural or unmodified state.

2 2 Water Pollution What is a Water Pollutant? A water pollutant can be defined as a physical, chemical or biological factor causing aesthetic or detrimental effects on aquatic life and on those who consume the water. Majority of the water pollutants are, however, in the form of chemicals which remain dissolved or suspended in water and give an environmental response which is often objectionable. Sometimes, physical and biological factors also act as pollutants. Among the physical factors, heat and radiations are important factors which have marked effects on organisms. Certain microorganisms present in water, especially pathogenic species, cause diseases to man and animals, and can be referred as biopollutants. Any factor can be characterized as a pollutant only under certain conditions, for example, phosphorus in nature is very important for growth of organisms, but the presence of its excessive quantities in water bodies lead to the problem of eutrophication (see Chapter 10). 1.2 RELATION OF WATER POLLUTION TO POPULATION AND ECONOMIC LEVELS Pollution can not be eliminated from the earth as long as even a single person survives on the earth, since the very existence of Man is cause of pollution. However, such pollution caused by individual s routine activities is negligible and apparently harmless, but it is the combined effect of larger populations that cause the significant pollution. The direct relationship of population densities and levels of pollution is apparent from the fact that in larger cities the problems of pollution are much more in comparison to the smaller cities and rural areas. The use of any resource usually generates a waste. As one has to use several resources for his existence, it can be said that survival and pollution are closely related to each other and go hand in hand. Nature has got its own mechanisms to take care of the wastes when they are in limited quantities. In the past times the people were living near the bank of rivers and disposing their wastes into them. The amount of wastes were so limited that the rivers hardly showed any symptoms of pollution due to their self purification capabilities. Later, with rise in population there has been an increase in amount of wastes to the proportion which was beyond the limit of self-purification capacity of waters. The accumulation of pollutants in waters resulted in the apparent and harmful effects. Water pollution also relates with the industrialization, civilization and living standards, which are directly related to the economic level of people. The water pollution seems to be more directly correlated to the demographic growth rather than the simple population growth. Therefore, the population growth and industrialization, both work synergistically to increase the levels of pollution. The developed countries, having comparatively low populations, are the most sufferer of the pollution because of their high economic levels, industrialization and mechanical lifestyle that consume more resources and energy. On the other hand the poor and developing countries have overpopulation, increasing their domestic wastes and sewage. Though these countries do not use much resources and energy, but short finances make a constrain on the treatment of wastes, which are often disposed off untreated causing severe water pollution problems. 1.3 WATER POLLUTION SCENARIO IN INDIA Most of the surface waters in India, including both rivers and lakes, are getting increasingly polluted due to onslaught of human activities of diverse nature. Though, several steps have been taken on a

3 General 3 broader front including National River and Lakes Conservation Plans, but the quality of the water resources seems to be far from satisfactory. This is mainly due to the lack of coordination between various governing bodies and proper operation and maintenance of treatment plants, and various other factors like reluctance of people and frequent failures of electricity due to which the untreated sewage or industrial wastes are directly discharged into the water bodies. The National River Conservation Directorate has no satisfactory mechanism to see that the installed effluent treatment plants work well. In fact, the quality of waters has shown a deterioration in past few years at several places. Although the rivers have significant self-purification capacity to assimilate and render many pollutants harmless, the existing pollution loads often exceed such natural capacities of self-purification. The River Ganga, which is considered most important river of India, is practically a toxic dump of highly polluting industries and Municipal Corporations which are situated in the Ganga basin all along its course. The major polluting cities of Ganga are Kanpur, Allahabad, Varanasi, Patna, Bhagalpur, and Kolkata. All these cities generate a huge amount of domestic sewage and have a large number of polluting industries, the wastes from which directly enter the river with or without treatment. The industrial town of Kanpur, with 45 tanneries and other polluting mills, is alone responsible for about 18% of the total water pollution of Ganga (Jha et al., 1997). The Hoogly river, an off shoot of Ganga, at Kolkata is similarly polluted heavily by the discharge of untreated or partially treated waste waters from several industries. The dredging, ship discharges, oil spills and other offshore activities also contribute significantly to the pollution of Hoogly river. River Yamuna, an important associate river of Ganga, is also heavily polluted like Ganga. It has several large and industrial cities on its banks like Yamunanagar, Sonepat, Panipat, Delhi, Agra and Mathura. Besides the municipal sewage, a large number of diverse industries like pulp and paper, sugar, tannery, steel plants, chemicals, rubber, glass, engineering, plastics, and food processing directly discharge their wastes into it. Delhi alone discharges its treated and untreated domestic sewage through small or large drains. 95% of the Yamuna pollution at Delhi is resulted due to discharge of wastewaters through seven major drains viz; Najafgarh, Yamunapur, Sen Nursing Home, Barathpula, Maharanibag, Kalkaji and Tuglakabad. In Delhi the Yamuna river is so polluted that beyond Okhala, it hardly supports any form of life. Table 1.1 gives the estimated pollution load at various cities along the Yamuna river. Not only the organic matter and nutrients, but several pesticides and heavy metals have also been found at alarming level in the river (Aggrawal, 1993). Another tributary of Ganga, the Gomti has almost the same story like Ganga and Yamuna rivers. It also embraces during its course of flow a number of big industrial units and towns, which discharge most of their treated or untreated wastes into the river. At Lucknow, it is highly polluted where over 330 million litres of sewage directly or indirectly finds its way into Gomti. The river at Lucknow has turned into a putrid flow of urban and industrial effluents. River Damodar, also a tributary of Ganga, which passes mainly through Jharkhand and West Bengal, is similarly polluted heavily. The Damodar river basin has about 250 coal mines and a large number of industrial units of various industrial towns like, Asansol, Durgapur, Bokaro, Sindri and Dhanbad. All these industrial townships utilize the river water and dump their liquid and solid wastes into the river. Besides, the runoff and discharges from the coal mining industry have made the river, one of the most polluted rivers of India. Huge quantities of acid-mine drainage enters the river, which has made the water lifeless in several stretches. Tonnes of coal dust also regularly enters the river from mining activities due to which the river has lost its natural colour, and also turned totally unfit for

4 4 Water Pollution human consumption. Similarly, all rivers passing through different mining areas are heavily suffered, and people are forced to use the polluted water in absence of other water resources. Table 1.1: Pollution load generation along the Yamuna river. Name of Town Flow (mld) BOD (t/day) Yamuna Nagar Karnal Panipat Sonepat Gurgaon Faridabad Delhi Saharanpur Muzzafarnagar Ghaziabad Noida Vrindavan Mathura Agra Etawah Source: CPCB (1996), mld = million litres per day The rivers in Deccan and south India, which include Godavari, Krishna, Mahanadi, Narmada, Kaveri, Tungabhadra and Tapti are also heavily polluted due to anthropogenic activities. The River Krishna, after originating from Mahabaleshwar hills flows in the plains of Maharashtra, Karnataka and Andhra Pradesh. In Maharashtra, it gets huge amount of pollutants from some sugar factories and domestic sewage. At Sangli (Maharashtra) it becomes almost a sewage drain at the time of low flow during summer. River Godavari has also several industrial units discharging their wastes into it. At Rajamundry in Andhra Pradesh, it receives high quantities of toxic wastes from paper industry. This has resulted into a permanent layer of aluminium hydroxide on the water surface resulting in total destruction of aquatic life (Jha et al., 1997). Tungabhadra river is highly polluted due to effluent from paper, pulp, rayon and steel industries. At Harihar in Karnataka it receives toxic effluents from Harihar Polyfibre, which has been the cause of severe pollution in a long stretch of river, making it almost lifeless. Tapti river gets heavily polluted in Gujarat and Maharashtra due to discharge of domestic sewage and industrial waste at Surat, Akola, Amravati, Dhule, Jalgaon, Bhusawal and Malegaon. Some small rivers like Kalu (Maharashtra), Cooum and Vaigai (Tamil Nadu) are highly polluted by domestic sewage and discharges of various types of industries situated along them. High levels of mercury have been found in Kalu river near Mumbai. This is story of only a few important and highly polluted rivers in India. There is hardly any river which is not polluted. Not only the discharge of domestic and industrial sewage are responsible for

5 General 5 water pollution, but non-point sources like natural, urban and agricultural run-off, and direct human activities in the form of bathing, cloth washing, vehicle washing, etc. are also responsible to a large extent for pollution. At the time of religious festivals due to immersion of idols and other offering, river pollution gets many-fold increased. Beside rivers, India is also rich in water resources in the form of lakes, reservoirs, tanks and ponds which are spread all across the country. These water bodies are not only important for water, but also for their ecological importance as they provide habitat to aquatic flora and fauna, as well as numerous species of birds including migratory birds. They may also comprise an important resource for sustainable tourism and recreation. Dumping of liquid and solid wastes beyond their assimilative capacity lead to severe pollution. The pollution studies so far made on these water bodies reveal that the water bodies, which are linked with human population, rapidly get polluted due to run-off, direct human activity and sewage discharge. The bodies of water, which remain away from human population, get polluted only slowly through natural sources. Tourist activities remain to be a significant source of water pollution as evidenced by the deterioration of Dal lake in Kashmir. Similarly Ooty lake is also grossly polluted and has recently got infested with water-hyacinth. The lakes of Udaipur and Bhopal are constantly shrinking mainly because of pollution. Not only the surface water sources, but groundwaters also get polluted by industrial wastes, urban sewage and agricultural run-off. However, the magnitude of groundwater pollution is much less compared to surface water as the soil acts as a filter retaining a large part of colloidal and soluble pollutants by mechanical trapping, adsorption and chemical reactions. Only soluble pollutants can contaminate the groundwaters and the extent of pollution is likely to be more in sandy soils, with high water table conditions. Pollutants often seep into the groundwaters from septic tanks, underground storage tanks, and lagoons and stabilization ponds used for wastewater treatment. The infiltration of liquid from refuse dumps, particularly in low lying areas, may also be of concern in polluting groundwater as commonly reported in urban areas. Mining is also responsible for polluting large areas of aquifers. The fertilizers and pesticides applied on land also find their way into groundwaters. Disposal of various kinds of wastewaters on land for treatment or irrigation is also responsible for groundwater pollution. Animal feed lots are also a source of groundwater pollution. The groundwater also gets contaminated naturally from the rocks with which it remains in contact. There are areas in the country where groundwater with fluoride beyond the permissible limit of 1.5 ppm commonly exist. Though the fluoride is found in many areas, Rao (1977) concluded that concentration of fluoride is highest in the arid and semiarid belts of western India. The segment of population affected by fluoride is estimated at about 25 million, spread over more than 200 districts in 17 States of the country. Some groundwaters of high rainfall areas are polluted naturally by excessive iron. This problem has often been observed in the groundwaters of Assam, West Bengal, Orissa and Kerala. Iron in toxic amounts as high as 20 ppm exists in deep tubewells as ferrous ion, and on taking out, it immediately changes to light yellow orange colour on oxidation and precipitates as ferric hydroxide. Nitrate is one of the commonest pollutants of groundwater. High quantities of nitrate have been found in most of the groundwaters in India. Use of commercial fertilizers is one of the common sources of nitrate pollution. Nitrate also remains in substantial quantities in sewage and many industrial

6 6 Water Pollution wastes. All organic matter finally gets converted into nitrate by biological oxidation by the process called nitrification. Nitrate can easily be seeped into the soil due to its poor capacity to remain adsorbed with the soil particles. Arsenic contamination of groundwater is also of concern in India. It has affected vast stretches of the State of West Bengal with nearly 13.8 million people at risk. Much attention has been given in the National Environment Policy of India to the conserve, manage and abatement of pollution of all kinds of water bodies including ground water resources. 1.4 WATER POLICIES AND PROGRAMMES IN INDIA As the rainfall occurs mostly in three to four months of monsoon, the water has to be stored in water resources like lakes, reservoirs and underground aquifers to get an uninterrupted supply of water throughout the year. The uneven distribution of rainfall, while makes certain areas water rich, others remain water poor. The erratic rainfall makes the problem further complicated with many areas remaining under long periods of drought making general scarcity of waters for years. Further, with increase in population, the total annual renewable freshwater is constantly on decline. It has currently reduced to 1821 m 3 per person per year from 5177 m 3 per person per year in The projected availability of this water is further reduced to 1341 m 3 per person per year in Any situation of water availability less than 1000 m 3 per person per year can be considered as a scarcity situation. Govt. of India has formulated several policies and programmes to combat the scarcity problem of water and to ensure that good quality water is available for diverse uses at all the places of human inhabitation in India. These programmes have drawn schemes for pure and adequate supply of drinking water to all, irrigation projects, river basin development and water conservation in different parts of the country. Some important water related policies and programmes are discussed briefly here. National Water Policy India first adopted a National Water Policy (NWP) in 1987, but with new issues and challenges emerging during the last decade, the policy has been reviewed and the new policy was adopted on April 1, 2002 by Fifth National Water Resources Council. The revised policy is a guideline for planned development and management of water resources at the national level. The national management of water resources appears to be the key word in the draft policy. The policy seeks equitable sharing and distribution of water among States including those water-short States that lie outside of a river basin. The policy lays stress upon the planning, development and management of water resources, effective settlement of disputes and time bound implementation of projects. The revised water policy has emphasized the maintenance of surface and ground water quality and treatment of effluents to acceptable levels. For this, it calls for the polluter to pay for polluting a water resource. Ecology, agroindustries and nonagricultural industries, and navigation and other uses are the new additions to the priorities, with the option that they could be modified if warranted by the local area. The salient features of the policy are as below: Stress on maintenance of irrigation projects. River basin Organizations to ensure development and management of interstate river basins.

7 General 7 Calls for dam safety legislation to ensure proper inspection, maintenance and surveillance. Calls for national policy for resettlement and rehabilitation of project affected people. Ecology given priority in water allocation; minimum flows in perennial streams mandated. Provides for participatory approach to water management, including water users Associations, private sector and modern information system. Non-conventional methods of water conservation like rain harvesting, artificial recharge of ground water, interbasin transfers, desalination of brackish or seawater stressed. River and Lake Conservations Plans Ganga was the first river which was taken up for cleaning under a Govt. plan. Ganga river basin is the largest in India supporting a population of more than 250 million people. Over 100 small and large towns are situated on the banks of Ganga discharging nearly 5,000 million litres of wastewaters daily including sewage and industrial effluents, making it highly polluted almost throughout its flow. The constantly degrading quality of water in Ganga led the Central Pollution Control Board in 1984 to make a survey of the river, which revealed that the river is polluted to the alarming levels. Realizing the religious, social and economic importance of the Ganga, the Central Govt. in June 1985 launched the Ganga Action Plan (GAP) to clean the river. In the same year the Central Ganga Authority (CGA) was also constituted to guide and oversee the implementation of the programme for restoring water quality of the river. The main objective of the GAP was to reduce the pollution load and establish a self-sustaining sewage treatment system to improve the quality of river water. Although, GAP began with a focus on prevention of river pollution on account of municipal sewage from Class-I cities having a population of over 1 lakh, the objective of GAP was recasted in 1987 to envisage the restoring river water quality to bathing class standard. The idea of bathing class was mainly introduced to see that one can easily enter the river without fear from severe skin disorders and intestinal infections. This can be achieved by maintaining certain norms and essential standards of water quality. It was decided later that the whole action plan must be implemented in two stages. In the first phase, out of nearly 1400 million litres per day (mld) of sewage generated in 25 Class-I towns along the river in Uttar Pradesh, Bihar and West Bengal, 870 mld was proposed to be diverted and treated. The first stage of Ganga Action Plan (GAP-I) was originally planned to be completed by March 1990, but was later extended progressively to March The GAP was made later an integrated plan covering the tributaries of the Ganga that bring substantial quantities of pollutants into the Ganga. Thus, GAP was envisaged in 1991 to clean the tributaries of Ganga under the second stage (GAP-II). The pollution abatement works were to be carried out on the tributaries of Ganga, mainly Yamuna, Gomti and Damodar. However, the GAP-II was to work in tandem with National River Conservation Plan (NRCP). The completion of the second phase was scheduled for December It was realized later that this is not only the Ganga and its tributaries, but other rivers of India must also be cleaned. This led to the launch of National River Conservation Plan (NRCP) in 1995 to clean several other important rivers flowing through various States. The NRCP is responsible for maintaining wholesomeness of water quality of major rivers by implementing various pollution abatement schemes. This plan was to be implemented in 157 towns along 31 stretches of the polluted rivers in 18

8 8 Water Pollution States at a total cost of Rs crores. For cleaning and documenting pollution in all the rivers of India, National River Conservation Authority (NRCA) was constituted under which the NRCP currently works. At present GAP-I and GAP-II have ceased to exist and merged with National River Conservation Plan. In order to manage pollution of rivers, the GAP and NRCP devised core and noncore plans. The core plans were mainly to tackle point sources from sewage that included the interception and diversion of sewage, and construction of treatment plants. Noncore schemes, which were basically to tackle nonpoint sources, included low cost sanitation, river front development, electric and improved wood crematoria, and tackling pollution from solid waste dumping, open defecation and dumping of dead bodies etc. Although the treatment of industrial wastes was not included in the action plan, it became necessary to take special steps to deal with the seriousness of industrial pollution at specific locations. Under the schemes of GAP, the Automatic Water Quality Monitoring Stations (AWQMS) were also installed at certain places. Water is being continuously monitored through these AWQMS. The water quality data on important parameters like ph, temperature, conductivity, dissolved oxygen and turbidity are recorded every 5 minutes. Similarly, to focus upon urban lakes subjected to anthropogenic pressure and to prevent pollution from point and non-point sources and treatment of the catchment area etc. a National Lake Conservation Plan (NCLP) was also started in The major benefits from the river and lake conservation plans include the following: 1. Non-user benefits for urban and nonurban areas may include improvement in general aesthetics, less polluted water for ritual bathing, improved biodiversity and recreation. 2. User benefits in the form of availability of clean water for pilgrims, tourists and inhabitants living near the river. 3. Health benefits due to reduction of skin diseases and other water related disorders in man and animals. 4. Agricultural benefits can be seen as better water for agriculture and availability of sludge from wastewater treatment plants that can be used as a manure in the fields. 5. Other benefits can include: An increase in the population of aquatic biota like turtles, otters, dolphins; better fisheries and improved catch in clean waters and reduction of toxins in water, etc. Drinking Water Coverage Policies The Govt. of India adopts the following norms for drinking water coverage: litres per capita per day of safe drinking water for humans. 2. Under Desert Development Programme Areas, additional 30 litres for cattle. 3. One hand pump or stand post for every 250 persons. 4. The water supply should exist within the habitations, within 1.6 km in the plains and within 100 meters elevation in hilly areas. At present 94% of habitations are fully covered under these norms, 5.5% partially covered and only 0.5% are not covered.

9 General 9 Rural Water Supply Programmes To assist the States and Union Territories for covering maximum rural population Govt. of India has started a programme called Accelerated Rural Water Supply Programme (ARWSP) in This programme was given a mission approach with the launch of the National Drinking Water Mission (NDWM) in The NDWM was renamed as the Rajiv Gandhi National Drinking Water Mission (RGNDWM) in The major objective of the programme has been to cover the not-covered, partially-covered and quality affected rural habitations. Through this programme, out of a total of about 1.42 million rural habitations in the country, 1.33 million habitations now have access to safe drinking water. To maintain the sustainability of the drinking water schemes in rural areas, the Govt. started Sector Reforms Programmes in March 1999 to ensure active participation of the community in rural water supply. The reforms include adoption of a demand responsive approach based on empowerment of village communities, where they choose the service they want and for which they are willing to pay. The Sector Reform Programme is now being expanded as the Swajaldhara programme launched in The special feature of the scheme is that it will be implemented, maintained and owned by the community with 90% contribution from the Govt. and 10% from the community towards capital cost. Urban Water Supply Programmes To augment the safe water supply to urban population a programme called Accelerated Urban Water Supply Programme (AUWSP) was launched by Govt. of India during It aims to provide water supply to 2151 towns with less than 20,000 population as per 1991 census. Priority has been given to towns with special problems like low per capita water supply, very distant or deep water source, drought-prone areas, with excess salinity, fluoride and iron content, and high incidence of waterborne diseases. Besides, AUWSP, urban water supply has also been augmented through the schemes of Integrated Development of Small and Medium Towns (IDSMT) and the Mega City Scheme started in covering Mumbai, Kolkata, Chennai and Bangalore. Questions 1. Define pure and polluted waters. 2. What is a water pollutant? Explain with examples. 3. How do population and economic levels relate with water pollution? 4. Describe briefly the river pollution in India. 5. Give salient features of National Water Policy of India. 6. Write an account of River Action Plans in India. What is the current status of Ganga Action Plan? 7. What are the policies and programmes of Govt. of India with regard to drinking water supply.