Water pollution is the contamination of water bodies (e.g. lakes, rivers, oceans, aquifers and groundwater). This form of environmental degradation occurs when pollutants are directly or indirectly discharged into water bodies without adequate treatment to remove harmful compounds.
Water pollution affects the entire biosphere of plants and organisms living in these water bodies, as well as organisms and plants that might be exposed to the water. In almost all cases the effect is damaging not only to individual species and populations, but also to the natural biological communities.
Water pollution is a major global problem which requires ongoing evaluation and revision of water resource policy at all levels (international down to individual aquifers and wells). It has been suggested that water pollution is the leading worldwide cause of deaths and diseases, and that it accounts for the deaths of more than 14,000 people daily. An estimated 580 people in India die of water pollution related illness every day. About 90 percent of the water in the cities of China is polluted. As of 2007, half a billion Chinese had no access to safe drinking water. In addition to the acute problems of water pollution in developing countries, developed countries also continue to struggle with pollution problems. For example, in the most recent national report on water quality in the United States, 44 percent of assessed stream miles, 64 percent of assessed lake acres, and 30 percent of assessed bays and estuarine square miles were classified as polluted. The head of China's national development agency said in 2007 that one quarter the length of China's seven main rivers were so poisoned the water harmed the skin.
Water is typically referred to as polluted when it is impaired by anthropogenic contaminants and either does not support a human use, such as drinking water, or undergoes a marked shift in its ability to support its constituent biotic communities, such as fish. Natural phenomena such as volcanoes, algae blooms, storms, and earthquakes also cause major changes in water quality and the ecological status of water.
Although interrelated, surface water and groundwater have often been studied and managed as separate resources. Surface water seeps through the soil and becomes groundwater. Conversely, groundwater can also feed surface water sources. Sources of surface water pollution are generally grouped into two categories based on their origin.
Point source water pollution refers to contaminants that enter a waterway from a single, identifiable source, such as a pipe or ditch. Examples of sources in this category include discharges from a sewage treatment plant, a factory, or a city storm drain. The U.S. Clean Water Act (CWA) defines point source for regulatory enforcement purposes. The CWA definition of point source was amended in 1987 to include municipal storm sewer systems, as well as industrial storm water, such as from construction sites.
Nonpoint source pollution refers to diffuse contamination that does not originate from a single discrete source. NPS pollution is often the cumulative effect of small amounts of contaminants gathered from a large area. A common example is the leaching out of nitrogen compounds from fertilized agricultural lands. Nutrient runoff in storm water from "sheet flow" over an agricultural field or a forest are also cited as examples of NPS pollution.
Contaminated storm water washed off of parking lots, roads and highways, called urban runoff, is sometimes included under the category of NPS pollution. However, because this runoff is typically channeled into storm drain systems and discharged through pipes to local surface waters, it becomes a point source.
Main article: Groundwater pollution
Interactions between groundwater and surface water are complex. Consequently, groundwater pollution, also referred to as groundwater contamination, is not as easily classified as surface water pollution. By its very nature, groundwater aquifers are susceptible to contamination from sources that may not directly affect surface water bodies, and the distinction of point vs. non-point source may be irrelevant. A spill or ongoing release of chemical or radionuclide contaminants into soil (located away from a surface water body) may not create point or non-point source pollution but can contaminate the aquifer below, creating a toxic plume. The movement of the plume, called a plume front, may be analyzed through a hydrological transport model or groundwater model. Analysis of groundwater contamination may focus on soil characteristics and site geology, hydrogeology, hydrology, and the nature of the contaminants.
The specific contaminants leading to pollution in water include a wide spectrum of chemicals, pathogens, and physical changes such as elevated temperature and discoloration. While many of the chemicals and substances that are regulated may be naturally occurring (calcium, sodium, iron, manganese, etc.) the concentration is often the key in determining what is a natural component of water and what is a contaminant. High concentrations of naturally occurring substances can have negative impacts on aquatic flora and fauna.
Oxygen-depleting substances may be natural materials such as plant matter (e.g. leaves and grass) as well as man-made chemicals. Other natural and anthropogenic substances may cause turbidity (cloudiness) which blocks light and disrupts plant growth, and clogs the gills of some fish species.
Many of the chemical substances are toxic.:229 Pathogens can produce waterborne diseases in either human or animal hosts. Alteration of water's physical chemistry includes acidity (change in pH), electrical conductivity, temperature, and eutrophication. Eutrophication is an increase in the concentration of chemical nutrients in an ecosystem to an extent that increases the primary productivity of the ecosystem. Depending on the degree of eutrophication, subsequent negative environmental effects such as anoxia (oxygen depletion) and severe reductions in water quality may occur, affecting fish and other animal populations.
China's extraordinary economic growth, industrialization, and urbanization, coupled with inadequate investment in basic water supply and treatment infrastructure, has resulted in widespread water pollution.
Disease-causing microorganisms are referred to as pathogens. Although the vast majority of bacteria are either harmless or beneficial, a few pathogenic bacteria can cause disease. Coliform bacteria, which are not an actual cause of disease, are commonly used as a bacterial indicator of water pollution. Other microorganisms sometimes found in contaminated surface waters that have caused human health problems include:
High levels of pathogens may result from on-site sanitation systems (septic tanks, pit latrines) or inadequately treated sewage discharges. This can be caused by a sewage treatment plant operating without a sterilization stage or long retention polishing capability. Older cities with ageing infrastructure may have leaky sewage collection systems (pipes, pumps, valves), which can cause sanitary sewer overflows. Some cities also have combined sewers, which may discharge untreated sewage during rain storms.Silt (sediment) from sewage discharges also pollutes water bodies.
Pathogen discharges may also be caused by poorly managed livestock operations.
Organic, inorganic and macroscopic contaminants
Contaminants may include organic and inorganic substances.
Organic water pollutants include:
- Disinfection by-products found in chemically disinfecteddrinking water, such as chloroform
- Food processing waste, which can include oxygen-demanding substances, fats and grease
- Insecticides and herbicides, a huge range of organohalides and other chemical compounds
- Petroleum hydrocarbons, including fuels (gasoline, diesel fuel, jet fuels, and fuel oil) and lubricants (motor oil), and fuel combustion byproducts, from storm waterrunoff
- Volatile organic compounds, such as industrial solvents, from improper storage.
- Chlorinated solvents, which are dense non-aqueous phase liquids, may fall to the bottom of reservoirs, since they don't mix well with water and are denser.
- Various chemical compounds found in personal hygiene and cosmetic products
- Drug pollution involving pharmaceutical drugs and their metabolites
Inorganic water pollutants include:
Macroscopic pollution – large visible items polluting the water – may be termed "floatables" in an urban storm water context, or marine debris when found on the open seas, and can include such items as:
- Trash or garbage (e.g. paper, plastic, or food waste) discarded by people on the ground, along with accidental or intentional dumping of rubbish, that are washed by rainfall into storm drains and eventually discharged into surface waters.
- Nurdles, small ubiquitous waterborne plastic pellets. Seeplastic pollution.
- Shipwrecks, large derelict ships.
Main article: Thermal pollution
Thermal pollution is the rise or fall in the temperature of a natural body of water caused by human influence. Thermal pollution, unlike chemical pollution, results in a change in the physical properties of water. A common cause of thermal pollution is the use of water as a coolant by power plants and industrial manufacturers. Elevated water temperatures decrease oxygen levels, which can kill fish and alter food chain composition, reduce species biodiversity, and foster invasion by new thermophilic species.:375 Urban runoff may also elevate temperature in surface waters.
Thermal pollution can also be caused by the release of very cold water from the base of reservoirs into warmer rivers.
Transport and chemical reactions of water pollutants
See also: Marine pollution
Most water pollutants are eventually carried by rivers into the oceans. In some areas of the world the influence can be traced one hundred miles from the mouth by studies using hydrology transport models. Advanced computer models such as SWMM or the DSSAM Model have been used in many locations worldwide to examine the fate of pollutants in aquatic systems. Indicator filter-feeding species such as copepods have also been used to study pollutant fates in the New York Bight, for example. The highest toxin loads are not directly at the mouth of the Hudson River, but 100 km (62 mi) south, since several days are required for incorporation into planktonic tissue. The Hudson discharge flows south along the coast due to the coriolis force. Further south are areas of oxygen depletion caused by chemicals using up oxygen and by algae blooms, caused by excess nutrients from algal cell death and decomposition. Fish and shellfish kills have been reported, because toxins climb the food chain after small fish consume copepods, then large fish eat smaller fish, etc. Each successive step up the food chain causes a cumulative concentration of pollutants such as heavy metals (e.g. mercury) and persistent organic pollutants such as DDT. This is known as bio-magnification, which is occasionally used interchangeably with bio-accumulation.
Large gyres (vortexes) in the oceans trap floating plastic debris. The North Pacific Gyre, for example, has collected the so-called "Great Pacific Garbage Patch", which is now estimated to be one hundred times the size of Texas. Plastic debris can absorb toxic chemicals from ocean pollution, potentially poisoning any creature that eats it. Many of these long-lasting pieces wind up in the stomachs of marine birds and animals. This results in obstruction of digestive pathways, which leads to reduced appetite or even starvation.
Many chemicals undergo reactive decay or chemical change, especially over long periods of time in groundwater reservoirs. A noteworthy class of such chemicals is the chlorinated hydrocarbons such as trichloroethylene (used in industrial metal degreasing and electronics manufacturing) and tetrachloroethylene used in the dry cleaning industry. Both of these chemicals, which are carcinogens themselves, undergo partial decomposition reactions, leading to new hazardous chemicals (including dichloroethylene and vinyl chloride).
Groundwaterpollution is much more difficult to abate than surface pollution because groundwater can move great distances through unseen aquifers. Non-porous aquifers such as clays partially purify water of bacteria by simple filtration (adsorption and absorption), dilution, and, in some cases, chemical reactions and biological activity; however, in some cases, the pollutants merely transform to soil contaminants. Groundwater that moves through open fractures and caverns is not filtered and can be transported as easily as surface water. In fact, this can be aggravated by the human tendency to use natural sinkholes as dumps in areas of karst topography.
There are a variety of secondary effects stemming not from the original pollutant, but a derivative condition. An example is silt-bearing surface runoff, which can inhibit the penetration of sunlight through the water column, hampering photosynthesis in aquatic plants.
Water pollution may be analyzed through several broad categories of methods: physical, chemical and biological. Most involve collection of samples, followed by specialized analytical tests. Some methods may be conducted in situ, without sampling, such as temperature. Government agencies and research organizations have published standardized, validated analytical test methods to facilitate the comparability of results from disparate testing events.
Sampling of water for physical or chemical testing can be done by several methods, depending on the accuracy needed and the characteristics of the contaminant. Many contamination events are sharply restricted in time, most commonly in association with rain events. For this reason "grab" samples are often inadequate for fully quantifying contaminant levels. Scientists gathering this type of data often employ auto-sampler devices that pump increments of water at either time or discharge intervals.
Sampling for biological testing involves collection of plants and animals from the surface water body. Depending on the type of assessment, the organisms may be identified for biosurveys (population counts) and returned to the water body, or they may be dissected for bioassays to determine toxicity.
Further information: Water quality § Sampling and measurement
Common physical tests of water include temperature, solids concentrations (e.g., total suspended solids (TSS)) and turbidity.
See also: water chemistry analysis and environmental chemistry
Water samples may be examined using the principles of analytical chemistry. Many published test methods are available for both organic and inorganic compounds. Frequently used methods include pH, biochemical oxygen demand (BOD),:102chemical oxygen demand (COD),:104 nutrients (nitrate and phosphorus compounds), metals (including copper, zinc, cadmium, lead and mercury), oil and grease, total petroleum hydrocarbons (TPH), and pesticides.
Main article: Bioindicator
Biological testing involves the use of plant, animal or microbial indicators to monitor the health of an aquatic ecosystem. They are any biological species or group of species whose function, population, or status can reveal what degree of ecosystem or environmental integrity is present. One example of a group of bio-indicators are the copepods and other small water crustaceans that are present in many water bodies. Such organisms can be monitored for changes (biochemical, physiological, or behavioral) that may indicate a problem within their ecosystem.
For microbial testing of drinking water, see Bacteriological water analysis.
Control of pollution
Decisions on the type and degree of treatment and control of wastes, and the disposal and use of adequately treated wastewater, must be based on a consideration all the technical factors of each drainage basin, in order to prevent any further contamination or harm to the environment.
Main article: Sewage treatment
In urban areas of developed countries, domestic sewage is typically treated by centralized sewage treatment plants. Well-designed and operated systems (i.e., secondary treatment or better) can remove 90 percent or more of the pollutant load in sewage. Some plants have additional systems to remove nutrients and pathogens.
Cities with sanitary sewer overflows or combined sewer overflows employ one or more engineering approaches to reduce discharges of untreated sewage, including:
- utilizing a green infrastructure approach to improve storm water management capacity throughout the system, and reduce the hydraulic overloading of the treatment plant
- repair and replacement of leaking and malfunctioning equipment
- increasing overall hydraulic capacity of the sewage collection system (often a very expensive option).
A household or business not served by a municipal treatment plant may have an individual septic tank, which pre-treats the wastewater on site and infiltrates it into the soil.
Industrial wastewater treatment
Main article: Industrial wastewater treatment
Some industrial facilities generate ordinary domestic sewage that can be treated by municipal facilities. Industries that generate wastewater with high concentrations of conventional pollutants (e.g. oil and grease), toxic pollutants (e.g. heavy metals, volatile organic compounds) or other non-conventional pollutants such as ammonia, need specialized treatment systems. Some of these facilities can install a pre-treatment system to remove the toxic components, and then send the partially treated wastewater to the municipal system. Industries generating large volumes of wastewater typically operate their own complete on-site treatment systems. Some industries have been successful at redesigning their manufacturing processes to reduce or eliminate pollutants, through a process called pollution prevention.
Heated water generated by power plants or manufacturing plants may be controlled with:
Agricultural wastewater treatment
Main article: Agricultural wastewater treatment
Non point source controls
Sediment (loose soil) washed off fields is the largest source of agricultural pollution in the United States. Farmers may utilize erosion controls to reduce runoff flows and retain soil on their fields. Common techniques include contour plowing, crop mulching, crop rotation, planting perennial crops and installing riparian buffers.:pp. 4-95–4-96
Nutrients (nitrogen and phosphorus) are typically applied to farmland as commercial fertilizer, animal manure, or spraying of municipal or industrial wastewater (effluent) or sludge. Nutrients may also enter runoff from crop residues, irrigation water, wildlife, and atmospheric deposition.:p. 2–9 Farmers can develop and implement nutrient management plans to reduce excess application of nutrients:pp. 4-37–4-38 and reduce the potential for nutrient pollution.
To minimize pesticide impacts, farmers may use Integrated Pest Management (IPM) techniques (which can include biological pest control) to maintain control over pests, reduce reliance on chemical pesticides, and protect water quality.
Point source wastewater treatment
Farms with large livestock and poultry operations, such as factory farms, are called concentrated animal feeding operations or feedlots in the US and are being subject to increasing government regulation. Animal slurries are usually treated by containment in anaerobic lagoons before disposal by spray or trickle application to grassland. Constructed wetlands are sometimes used to facilitate treatment of animal wastes. Some animal slurries are treated by mixing with straw and composted at high temperature to produce a bacteriologically sterile and friable manure for soil improvement.
Erosion and sediment control from construction sites
Sediment from construction sites is managed by installation of:
Discharge of toxic chemicals such as motor fuels and concrete washout is prevented by use of:
- spill prevention and control plans, and
- specially designed containers (e.g. for concrete washout) and structures such as overflow controls and diversion berms.
Control of urban runoff (storm water)
Main article: Urban runoff
See also: Green infrastructure
Effective control of urban runoff involves reducing the velocity and flow of storm water, as well as reducing pollutant discharges. Local governments use a variety of storm water management techniques to reduce the effects of urban runoff. These techniques, called best management practices (BMPs) in the U.S., may focus on water quantity control, while others focus on improving water quality, and some perform both functions.
Pollution prevention practices include low-impact development techniques, installation of green roofs and improved chemical handling (e.g. management of motor fuels & oil, fertilizers and pesticides). Runoff mitigation systems include infiltration basins, bioretention systems, constructed wetlands, retention basins and similar devices.
Thermal pollution from runoff can be controlled by storm water management facilities that absorb the runoff or direct it into groundwater, such as bioretention systems and infiltration basins. Retention basins tend to be less effective at reducing temperature, as the water may be heated by the sun before being discharged to a receiving stream.:p. 5–58
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Pollution of the Ganges (or Ganga), the largest river in India, poses significant threats to human health and the larger environment. Severely polluted with human waste and industrial contaminants, the river provides water to about 40% of India's population across 11 states, serving an estimated population of 500 million people or more, more than any other river in the world.
Today, Ganges is considered to be the fifth most polluted river in the world.Raghubir Singh has noted that no one in India spoke of the Ganges as polluted until the late 1970s. However, pollution has been an old and continuous process in the river as by the time people were finally speaking of the Ganges as polluted, stretches of over six hundred kilometres were essentially ecologically dead zones.
A number of initiatives have been undertaken to clean the river but failed to deliver desired results. After getting elected, India's Prime minister Narendra Modi affirmed to work in cleaning the river and controlling pollution. Subsequently, the Namami Ganga project was announced by the government in the July 2014 budget. An estimated Rs 2,958 Crores (US$460 million) have been spent till July 2016 in various efforts in cleaning up of the river.
The main causes of water pollution in the Ganges river are: the increase in the population density, various human activities (such as bathing, washing clothes, and the bathing of animals), and dumping of various harmful industrial waste into the river.
The river flows through 29 cities with population over 100,000; 23 cities with population between 50,000 and 100,000, and about 48 towns. A large proportion of the sewage water with higher organic load in the Ganges is from this population through domestic water usage.
Because of the establishment of a large number of industrial cities on the bank of river Ganga like Kanpur, Allahabad, Varanasi and Patna, countless tanneries, chemical plants, textile mills, distilleries, slaughterhouses, and hospitals prosper and grow along this and contribute to the pollution of the Ganga by dumping untreated waste into it. One coal-based power plant on the banks of the Pandu River, a Ganges tributary near the city of Kanpur, burns 600,000 tons of coal each year and produces 210,000 tons of fly ash. The ash is dumped into ponds from which a slurry is filtered, mixed with domestic wastewater, and then released into the Pandu River. Fly ash contains toxic heavy metals such as lead and copper. The amount of parts per million of copper released in the Pandu before it even reaches the Ganges is a thousand times higher than in uncontaminated water. Industrial effluents are about 12% of the total volume of effluent reaching the Ganga. Although a relatively low proportion, they are a cause for major concern because they are often toxic and non-biodegradable.
During festival seasons, over 70 million people bathe in the Ganga  to clean themselves from their past sins. Some materials like food, waste or leaves are left in the Ganga which are responsible for its pollution. While people drinking from the Ganga and bathing in its waters are spiritual experiences, it is also part of Indian traditional beliefs that being cremated on its banks and to float down the Ganges will atone for the deceased past sins and carry him directly to salvation. In Varanasi alone, an estimated forty thousand bodies are cremated every year, many of those are only half-burnt.
Dams and Pumping stations
Built in 1854 during the British colonisation of India, the Haridwar dam has led to decay of the Ganga by greatly diminishing the flow of the river. The Farakka Barrage was built originally to divert fresh water into the Hooghly River but has since caused an increase of salinity in the downstream Ganga river, having a damaging effect on the ground water and soil along the river. The barrage has caused major tension between Bangladesh and India. Bangladesh is actively considering to construct Ganges Barrage Project for mitigating the salinity problem. The government of India has planned about 300 dams on the Ganga and its tributaries in the near future despite a government-commissioned green panel report that has recommended scrapping 34 of the dams citing environmental concerns.
Three more barrages across Ganga main river are existing at Bijnor, Narora and Kanpur. The barrages at Bijnor and Narora divert all the water including baseflows during dry season to the canals for irrigating vast area up to Allahabad city. Most of the water available at the upstream of the Kanpur barrage is used during dry season for the cities drinking water needs. Downstream of Kanpur barrage, adequate water is not available from the barrage to dilute the polluted water reaching the main river during the dry seasons of year.
There are number of pumping stations located on the banks (right and left) of Ganga river down stream of Kanpur barrage serving the irrigation requirements of huge area. These large pump houses are located at Rukunpur 26°10′21″N80°38′57″E / 26.17250°N 80.64917°E / 26.17250; 80.64917, Kanjauli Kachhar 25°17′37″N82°13′15″E / 25.29361°N 82.22083°E / 25.29361; 82.22083, Hakanipur Kalan 25°12′57″N83°01′15″E / 25.21583°N 83.02083°E / 25.21583; 83.02083, Bhosawali 25°20′46″N83°10′11″E / 25.34611°N 83.16972°E / 25.34611; 83.16972, Shekpur 25°32′13″N83°11′57″E / 25.53694°N 83.19917°E / 25.53694; 83.19917, Chochakpur 25°28′55″N83°25′11″E / 25.48194°N 83.41972°E / 25.48194; 83.41972, Lamui 25°23′20″N83°32′11″E / 25.38889°N 83.53639°E / 25.38889; 83.53639, Chausa 25°31′11″N83°54′04″E / 25.51972°N 83.90111°E / 25.51972; 83.90111, etc. (Refer to Google Earth maps) These lift irrigation schemes are pumping out most of the base flows available in the main river down stream of Kanpur city.
To make Ganga river live/flowing and dilute the polluted water inflows from habitations and industries, at least 5000 cusecs flow is required from Narora to Farakka as minimum environmental flow during the eight months dry season. This is possible by constructing storage reservoirs of capacity 100 Tmcft across Ganga tributaries located up stream of Narora city and reserving the stored water only for minimum environmental flows. In addition, a series of cascading barrage cum bridges are to be constructed across the river from Kanpur to Allahabad to increase the surface area of impounded polluted water in the river so that it serves as vast natural oxidation ponds. The accumulated sediments/sludge would get washed away during the annual monsoon floods. Already number of barrages are planned between Farakka and Allahabad to make the 1620 km length of the river navigable from Haldia to Allahabad under National Waterway 1 project which can be extended up the Kanpur.
A 2006 measurement of pollution in the Ganga revealed that river water monitoring over the previous 12 years had demonstrated fecal coliform counts up to 100,000,000 MPN (most probable number) per 100 ml and biological oxygen demand levels averaging over 40 mg/l in the most polluted part of the river in Varanasi. The overall rate of water-borne/enteric disease incidence, including acute gastrointestinal disease, was estimated to be about 66%.
A systematic classification done by Uttarakhand Environment Protection and Pollution Control Board’s (UEPPCB) on river waters into the categories A: safe for drinking, B: safe for bathing, C: safe for agriculture, and D: excessive pollution, put the Ganga in D. Coliform bacteria levels in the Ganga have also been tested to be at 5,500, a level too high to be safe for agricultural use let alone drinking and bathing.
The leather industry in Kanpur which employs around 50,000 people in more than 400 tanneries uses chemicals such as toxic chromium compounds. Effectively, chromium levels have not decreased in the Ganga even after a common treatment plant was established in 1995. It now stands at more than 70 times the recommended maximum level.
A study conducted by the National Cancer Registry Program (NCRP) under the Indian Council of Medical Research in 2012, suggested that "those living along its banks in Uttar Pradesh, Bihar and Bengal are more prone to cancer than anywhere else in the country".
The results of mercury analysis in various specimens collected along the basin indicated that some fish muscles tended to accumulate high levels of mercury. Of it, approximately 50–84% was organic mercury. A strong positive correlation between mercury levels in muscle with food habit and fish length was found.
The Ganges River dolphin is one of few species of fresh water dolphins in the world. Listed as an endangered species, their population is believed to be less than 2000. Hydroelectric and irrigation dams along the Ganga that prevents the dolphins from travelling up and down river is the main reason for their reducing population. The Ganges soft-shelled turtle (Aspideretes Gangeticus) is found in the Ganges, Indus, and Mahanadi river systems of Pakistan, northern India, Bangladesh, and southern Nepal. This turtle inhabits deep rivers, streams, large canals, lakes and ponds, with a bed of mud or sand. According to the International Union for Conservation of Nature, freshwater turtle species are vulnerable. Due to their long lifespan and high trophic level in the aquatic food web, turtles are vulnerable to heavy metals pollution, a major kind of pollution in the Ganges.
Some of the dams being constructed along the Ganga basin will submerge substantial areas of nearby forest. For example, the Kotli-Bhel dam at Devprayag will submerge 1200 hectares of forest, wiping out the river otters and the mahaseer fish that are found there. Wildlife biologists in India have been warning that the wild animals will find it difficult to cope with the changed situation.
An analysis of the Ganga water in 2006 and 2007 showed significant associations between water-borne/enteric disease pop and the use of the river for bathing, laundry, washing, eating, cleaning utensils, and brushing teeth. Water in the Ganga has been correlated to contracting dysentery, cholera, hepatitis, as well as severe diarrhoea which continues to be one of the leading causes of death of children in India.
During the summer and monsoon, hospital wards teem with children who need treatment for waterborne diseases - but according to Dr SC Singh, a paediatrician at Varanasi Shiv Prasad Gupta Hospital, their parents rarely mention that they have been swimming in the river. They don't appear to have made the connection, he says.
Ganga Mahasabha is an Indian organisation dedicated to the Ganga river, founded by Madan Mohan Malviya in 1905. After a long struggle, British India agreed on 5 November 1914 that the uninterrupted flow of holy river Ganga is the rudimentary right of Hindu believers. The day is known as a 'Aviral Ganga Samjhauta Divas' (Uninterrupted Ganga flow agreement day) in the history of India and the agreement came into existence on 19 December 1916 which is known as Agreement of 1916. The sanctity of the agreement is not preserved by the state and central governments of India after independence though it is legally valid. More and more river water is diverted for irrigation use converting the river into a polluted sewer.
Ganga Action Plan (GAP)
The Ganga action plan was launched by Shri Rajeev Gandhi, then by the Prime Minister of India, on 14 January 1986. Its main objective was to improve the water quality by the interception, diversion and treatment of domestic sewage and to prevent toxic and industrial chemical wastes from identified polluting units from entering the river. The other objectives of the Ganga Action Plan are as follows:
- Control of non-point pollution from agricultural run off, human defecation, cattle wallowing and the disposal of human remains in the river.
- Research and development to conserve the biotic diversity of the river to augment its productivity.
- Development of sewage treatment technology such as Up-flow Anaerobic Sludge Blanket (UASB) and sewage treatment through afforestation.
- Rehabilitation of soft-shelled turtles for pollution abatement.
- Resource recovery options such as methane production for energy generation and use of aquaculture for revenue generation.
- To act as trend setter for taking up similar action plans in other grossly polluted stretches in other rivers.
- The ultimate objective of the GAP is to have an approach of integrated river basin management considering the various dynamic interactions between abiotic and biotic eco-system.
Notwithstanding some delay in the completion of the first phase of the GAP it has generated considerable interest and set the scene for evolving a national approach towards replicating this program for the other polluted rivers of the country. The Government of India proposed to extend this model with suitable modifications to the national level through a National River Action Plan (NRAP). The NRAP mainly draws upon the lessons learnt and the experience gained from the GAP besides seeking the views of the State Governments and the other concerned Departments/Agencies. Under NRCP scheme the CPCB had conducted river basin studies and had identified 19 gross polluted stretches and 14 less polluted stretches along 19 rivers, which include 11 stretches situated along 7 rivers of M.P. It was very effective as compared to the previous launched programs.
National River Ganga Basin Authority (NRGBA)
Main article: National Ganga River Basin Authority
NRGBA was established by the Central Government of India, on 20 February 2009 under Section 3 of the Environment Protection Act, 1986. It declared the Ganga as the "National River" of India. The chair includes the Prime Minister of India and chief ministers of states through which the Ganga flows. In 2011, the World Bank "approved $1 billion in funding for the National Ganga River Basin Authority."
Supreme Court of India
The Supreme Court has been working on the closure and relocation of many of the industrial plants like Tulsi along the Ganga. In 2010 the government declared the stretch of river between Gaumukh and Uttarkashi an Eco-sensitive zone.
Namami Ganga Programme
In the budget tabled in Parliament on 10 July 2014, the Union Finance Minister Arun Jaitley announced an integrated Ganga development project titled 'Namami Gange' (meaning 'Obeisance to the Ganga river') and allocated ₹2,037 crore for this purpose.
As a part of the program, government of India ordered the shut down of 48 industrial units around Ganga.
The program has a budget outlay of Rs. 20,000 crore for the next 5 years. This is a significant four-fold increase over the expenditure in the past 30 years (Government of India incurred an overall expenditure of approximately Rs. 4000 crore on this task since 1985). The Centre will now take over 100% funding of various activities/ projects under this program. Taking a leaf from the unsatisfactory results of the earlier Ganga Action Plans, the Centre now plans to provide for operation and maintenance of the assets for a minimum 10-year period, and adopt a PPP/SPV approach for pollution hotspots.
In an attempt to bolster enforcement the Centre also plans to establish a 4-battalion Ganga Eco-Task Force. The program emphasises on improved co-ordination mechanisms between various Ministries/Agencies of Central and State governments. Major infrastructure investments which fall under the original mandate of other ministries viz. Urban Development (UD), Drinking Water & Sanitation (DWS), Environment Forests & Climate Change (EF&CC) etc., will be undertaken in addition.
‘Namami Gange’ will focus on pollution abatement interventions namely Interception, diversion and treatment of waste water flowing through the open drains through bio-remediation / appropriate in-situ treatment / use of innovative technologies / sewage treatment plants (STPs) / effluent treatment plant (ETPs); rehabilitation and augmentation of existing STPs and immediate short term measures for arresting pollution at exit points on river front to prevent inflow of sewage etc.
Significantly the approach is underpinned by socio-economic benefits that the program is expected to deliver in terms of job creation, improved livelihoods and health benefits to the vast population that is dependent on the river. 
Ganga Manthan was a national conference held to discuss issues and possible solutions for cleaning the river.
The conference aimed to take feedback from stakeholders and prepare a road map for rejuvenating the Ganga. The event was organised by the National Mission for clean Ganga on 7 July 2014 at Vigyan Bhawan in New Delhi.
Nepal to release water during lean flow period
Nepal has constructed many barrages (excluding joint projects with India) or pump houses to divert the lean season river flows for irrigation purpose. These water diversion projects are located near 28°25′29″N81°22′49″E / 28.42472°N 81.38028°E / 28.42472; 81.38028, 28°02′24″N81°57′12″E / 28.04000°N 81.95333°E / 28.04000; 81.95333, 27°52′51″N82°30′13″E / 27.88083°N 82.50361°E / 27.88083; 82.50361, 27°40′00″N83°06′49″E / 27.66667°N 83.11361°E / 27.66667; 83.11361, 27°42′17″N84°25′57″E / 27.70472°N 84.43250°E / 27.70472; 84.43250, 27°08′11″N85°29′01″E / 27.13639°N 85.48361°E / 27.13639; 85.48361, 26°53′09″N86°08′13″E / 26.88583°N 86.13694°E / 26.88583; 86.13694, 26°50′13″N87°09′01″E / 26.83694°N 87.15028°E / 26.83694; 87.15028, 26°41′05″N87°52′43″E / 26.68472°N 87.87861°E / 26.68472; 87.87861, etc. India being lower riparian state has right to claim share out of the river water flows from Nepal similar to India entered into river water sharing agreement with Bangladesh recognising it as lower riparian state. Till now there is no bilateral agreement between India and Nepal adhering to equitable sharing of river waters during the lean season. When Nepal releases water into India during the lean flow period, it would help in cleaning / diluting the polluted waters of downstream Ganga river up to Farakka barrage.
Water diversion from Manasarovar lake
For restoring the minimum environmental flows, it is difficult to identify nearly 100 Tmcft storage reservoirs in the hilly region of Ganga basin in India as the river is flowing through steep valleys. Already big storage reservoirs like Tehri and Ramganga are constructed at feasible locations. However the water of Manasarovar Lake located in China can be diverted to the upstream of Kanpur barrage (117 m msl) via Girijapur Barrage (129 m msl) located at 28°16′21″N81°05′09″E / 28.27250°N 81.08583°E / 28.27250; 81.08583 across the Ghaghara/Karnali river which is a tributary of Ganga river flowing from Tibet/China and Nepal.
Manasarovar Lake's surface area is 320 square kilometres (120 sq mi) and its maximum depth is 90 m (300 ft). It holds more than 100 tmcft water in its top 13 meters depth. At present it is overflowing into nearby Lake Rakshastal which is a land locked salt water endorheic lake. The annual water inflows from the catchment area of Manasarovar lake located at 4,590 metres (15,060 ft) above msl, can be diverted by gravity to the Karnali River basin of China through a 15-kilometre long tunnel.
The diverted water available continuously can be used in China for hydroelectric power generation where the head drop available is in excess of 800 meters over a 40 km long stretch. This would be a joint project of China, Nepal and India for controlling river water pollution and making the Ganga river live and flowing throughout the year. With the diversion of Manasarovar lake water to Ganga basin, Lake Rakshastal would turn into a Soda lake with further increase in water salinity which is useful in abstracting the water-soluble chemicals on commercial scale.
The fresh water inflows into Manasarovar lake can be augmented further substantially by gravity diversion of the inflows available from the major catchment area of Rakshastal lake to Manasarovar lake by constructing an earth dam isolating northern tip of Rakshastal lake where it is fed by its substantial catchment area and also connected to the Manasarovar lake.
Utilisation of Ganga and Bramhaputra flood waters to fight pollution in all rivers of India
Massive storage capacity fresh water reservoir can be established on the shallow sea area adjoining West Bengal, Odisha and Bangladesh coast by constructing sea dikes / bunds/ Causeway up to the depth of 15 meters. Water can be pumped from this artificial fresh water lagoon throughout the year with abundant solar power resource of India to many river basins in India for meeting needs of agriculture, maintaining environmental flows, salt export requirements, etc. Nearly 150 billion cubic meters (bcm) storage capacity fresh water reservoir/lagoon can be located on the sea area which stretches from Kutubdia island of Bangladesh (near 21°44′23″N91°53′01″E / 21.73972°N 91.88361°E / 21.73972; 91.88361) to the mouth of Brahmani River (near 20°49′37″N86°57′57″E / 20.82694°N 86.96583°E / 20.82694; 86.96583). The dike would be envisaged with gated barrages to pass to the sea the excess flood waters (total mean annual flow 1200 bcm) received from the Ganga, Brahmaputra rivers, etc. for limiting the full reservoir level (FRL) to 1.0 m above MSL.
From this reservoir, water is pumped up to the elevation of nearly 425 m MSL (near to 21°55′17″N86°09′07″E / 21.92139°N 86.15194°E / 21.92139; 86.15194) in the Brahmani river basin for further transfer in most of the area of Damodar River basin, Subarnarekha River basin, Brahmani River basin, Mahanadi River basin in Jharkhand, Odisha, Chhattisgarh and West Bengal states. The Hasdeo Bango reservoir (near 22°36′47″N82°37′27″E / 22.61306°N 82.62417°E / 22.61306; 82.62417) would receive the Ganga water and further pumped into the Narmada, Sone, Tapti, Yamuna, Sutlej, Luni, Chambal, Ghaggar, Ganga, etc. river basins for using in Maharashtra, Madhya Pradesh, Chhattisgarh, south Uttar Pradesh, south Bihar, Rajasthan, Gujarat, Haryana, Punjab and Delhi states. See Google earth maps for more geographical information. Further, water can be pumped into the Bagh reservoir and Upper Indravati reservoir located in Godavari River basin to transfer Ganga water into Godavari basin and further to south Indian river basins.
The minimum water flow from Bangladesh coast to the Bay of Bengal sea is 7,000 cumecs which is equal to 220 bcm annually. This water can also be put to use in addition to the impounded water by the water reservoir. The advantage of this scheme is that Ganga and Bramhaputra river waters can be stored on Bay of Bengal sea area and nearly 440 bcm water @ 14,000 cumecs transferred throughout the year to other river basins including Ganga basin at optimum pumping head.
Nearly 1000 million tons (500 million cubic meters) of sediment annually from Ganga and Brahmaputra rivers is settling in the sea coast of Bangladesh and India and the sea area is shallow (up to 15 m depth) for at least 50 km wide. Bangladesh plagued with high population density, can reclaim nearly 6,000 km2 (4% of its total land) area of sea by excavating/dredging sediment from the fresh water lagoon bed without any effect on the water storage of the off-shore fresh water reservoir.
The presence of the protective sea dike makes sub sea soil dredging easier and economical through protection from rough sea waves. This reclaimed area from the sea can be utilised for locating a megacity to cater to the modern needs of Bangladesh. This off shore dike would protect the Bangladesh from the wave and tidal activity during the frequent cyclones preventing human and property losses drastically and also from sea level rise due to global warming. Thus Bangladesh would also benefit immensely with this off shore fresh water reservoir project.
The sea dike extending 8 m above the mean sea level and 50 m wide at the top surface, would be nearly 520 km long connecting Indian mainland to South east of Bangladesh forming transnational high way and rail route from the Indian subcontinent to East Asia up to Singapore and China. Also this dike can be used as access way connecting deep sea ports located close to this dike. The proposed dike would be similar to the land reclamation of North Sea area called Delta Works in Netherlands. The experience of the Saemangeum Seawall already constructed in South Korea which is 33 km long and with 36 meters average depth, can be utilised for this project which is a lesser challenging project. Locks arrangement (similar to Panama canal) would be provided for the movement of ships from the open sea to harbours located in Bangladesh and India.
This lagoon area can also be used for shipping, ship breaking, ship building, etc. purposes.This man made lagoon can also be broken into parts and interconnected by under water tunnels/ ducts (nearly 500 meters long) in case existing ports and famous beach resorts must be protected. The cost of the total project including sea dikes, water pumping stations (60 GW), canal drop hydro power stations (15 GW), main canals, tunnels, aqueducts, barrages, distribution canals and the required solar power generation plants (200 GW) is estimated nearly 36 trillion (lakhcroresINR ) at year 2015 prices. Cheaper and continuously available hydro power supply for the water pumping needs would reduce the cost drastically. The irrigation potential of the project alone is 120 million acres with water supply throughout the year. It is a gigantic multi purpose project where cleaning of many major rivers of India (not Ganga river alone) from the water pollution is one of its purpose.
2010 Government clean-up campaign
In 2010, it was announced that "the Indian government has embarked on a $4 billion campaign to ensure that by 2020 no untreated municipal sewage or industrial runoff enters the 1,560-mile river." A World Bank spokesman described the plan in 2011, saying
Earlier efforts to clean the Ganga concentrated on a few highly polluting towns and centres and addressed 'end-of-the-pipe' wastewater treatment there; Mission Clean Ganga builds on lessons from the past, and will look at the entire Gangetic basin while planning and prioritising investment instead of the earlier town-centric approach.
Lobby group Sankat Mochan Foundation (SMF) "is working with GO2 Water Inc., a Berkeley, California, wastewater-technology company" to design a new Sewage treatment system for Varanasi.
Protests for cleaning Ganga
Main article: Nigamanand
In early 2011, a Hindu seer named Swami Nigamananda Saraswati fasted to death, protesting against illegal mining happening in the district of Haridwar (in Uttarakhand) resulting in pollution. Following his death in June 2011, his Ashram leader Swami Shivananda fasted for 11 days starting on 25 November 2011, taking his movement forward. Finally, the Uttarakhand government released an order to ban illegal mining all over the Haridwar district. According to administration officials, quarrying in the Ganga would now be studied by a special committee which would assess its environmental impacts on the river and its nearby areas.
Prof. G D Agrawal
Dr G. D. Agrawal is a notable environment activist and patron of Ganga Mahasabha (An organisation founded by Madan Mohan Malviya in 1905, demanding removal of dams on Ganga) who has been on a fast for 107 days protesting for a cleaner Ganga. Because of support from other social activists like Anna Hazare, the then Prime Minister of India, Manmohan Singh agreed to Prof. Agrawal's demands. Accordingly, he called for a National River Ganga Basin Authority (NRGBA) meeting and urged the authorities to utilise the ₹26 billion (US$520M) sanctioned "for creating sewer networks, sewage treatment plants, sewage pumping stations, electric crematoria, community toilets and development of river fronts".
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