Water pollution
- 2. Water One of the most important resources on our earth is water. Clean water is vital to our communities, economy, and most of all, our health. In fact, humans are made up of more than 60% water, and we need clean water to survive. Unfortunately, much of our water on earth is polluted and it is one of the major crises facing the world today. The causes of water pollution are many and we will need to take several measures in order to save this precious resource.
- 3. How much is the Water on our earth
- 4. Sources of Water Natural sources/surface water Found on earth naturally Found above land surface Man made sources/Arifiical sources – constructed by human Ground water – lies under the surface of land where it travels through and fills openings in the rocks Obtained by drilling wells
- 5. Identify the natural and man made sources of water
- 8. Water Pollution Pollution is the introduction of contaminants into the natural environment that cause adverse change. Pollution can take the form of chemical substances or energy, such as noise, heat, or light. . What is Water Pollution? Water Pollution is Contamination of Bodies of Water Bodies (ex: oceans, seas, lakes, rivers, aquifers, and groundwater etc.,) Any chemical, biological and environmental change in water causes adverse effect on health of living beings is called water pollution.
- 9. Examples When certain substances are present in water beyond their normal limit then the water is term as polluted. Whenever harmful substances such as sewage, toxic chemicals, silt, etc., get mixed with water, the water becomes polluted. The substances that pollute water are called water pollutants Pollutants – Sewage (d0mestic) and waste water (, Plastics, fertilizers, pesticides, insecticides, pesticides, harmful toxic organic and inorganic chemicals from industries like dyes, foodstuffs, medicines, etc.,metals, Electronic wastes, mining waste, garbage's, oil spills, etc., Gases H2S, NH3, Co2 Minerals such as Ca, Mg, Ar from soil, clay, mud, organic wastes get suspended in water,Nuclear waste and radiactive wastes, agricultural wastes etc.,pathogens, plant nutreints
- 10. How do you identify that water is polluted?- Color Acidity content Smell/odour Texture/appearance
- 12. Reason/Causes for Water Pollution Improper Sewage Disposal Fertilizer Run-Off Oil leaks /Spills Chemical Waste Dumping/Marine Dumping Radioactive Waste / Nuclear waste Discharge Untreated industrial waste water Rapid Urban Development
- 13. Improper/untreated sewage disposal Untreated sewage is thrown directly into rivers. It contains food wastes, detergents, microorganisms, etc. Water contaminated with sewage may contain bacteria, viruses, fungi and parasites which cause diseases like cholera, typhoid and jaundice Harmful chemicals, bacteria and pathogens can be found in sewage and wastewater even when it’s been treated. Sewage and wastewater from each household is released into the sea with fresh water. The pathogens and bacteria found in that wastewater breed disease, and therefore are a cause of health-related issues in humans and animals alike
- 14. Water born diseases The bacteria present in the faeces of mammals are indicators of the quality of water. If water has these bacteria, it means that it has been contaminated by fecal matter. If such water is used by us, it can cause various infections.
- 15. Oil spills Radioactive waste
- 16. Marine dumping Marine Dumping , dumping garbage into the waters of the ocean. Most water bodies get converted into dumping grounds by nearby localities. And this causes a huge problem because the dump contains everything from plastic, aluminum to glass, Styrofoam, etc. And since all the waste takes different time to degrade in the water, they tend to harm the aquatic life until degraded. The garbage produced by households in the form of paper, plastic, food, aluminum, rubber, glass, is collected and dumped into the sea in some countries. These items take 2 weeks to 200 years to decompose. When such things enter the sea, they not only cause water pollution but also harm animals in the sea.
- 17. Animal Waste The waste produced by animals washed away into the rivers when it rains. It then gets mixed up with other harmful chemicals and causes various water-borne diseases like cholera, diarrhea, dysentery, jaundice, and typhoid.
- 18. Mining Activities Mining is the process of crushing the rock and extracting coal and other minerals from the underground. These elements, when extracted in the raw form, contain harmful chemicals and can increase the number of toxic elements when mixed up with water, which may result in health problems. Mining activities emit a large amount of metal waste and sulfides from the rocks, which is harmful to the water
- 19. Underground Storage Leakage Transportation of coal and other petroleum products through underground pipes is well known. Accidental leakage may happen anytime and may cause damage to the environment and result in soil erosion.
- 20. Untreated industrial waste Industries and industrial sites across the world are a major contributor to water pollution. Many industrial sites produce waste in the form of toxic chemicals and pollutants, and though regulated, some still do not have proper waste management systems in place. In those rare cases, industrial waste is dumped into nearby freshwater systems. When industrial waste is not treated properly (or worse, not treated at all, it can very easily pollute the freshwater systems that it comes into contact with.
- 21. Industrial pollutants Many industries discharge harmful chemicals into rivers and streams, causing the pollution of water Examples are oil refineries, paper factories, textile and sugar mills and chemical factories. These industries cause chemical contamination of water. The chemicals released include arsenic, lead and fluorides which lead to toxicity in plants and animals. There are regulations to prevent this. Industries are supposed to treat the waste produced before discharging it into waters, but quite often the rules are not followed.
- 22. Waste water treatment plant
- 23. Fertilizers run off/ nutrient pollution Nutrient pollution, a form of water pollution refers to contamination by excessive inputs of nutrients It is a primary cause of eutrophication of surface waters, in which excess nutrients, usually nitrogen or phosphorus stimulate algal growth. Sources of nutrient pollution include surface runoff from farm fields and pastures, discharges from septic tanks and feedlots and emissions from combustion
- 24. Algae blooming/Eutrophication The chemicals available in the water body promote the growth of algae. These algae end up forming a thick layer over the ponds and lakes. The bacteria present in the water tend to feed on algae, causing the amount of oxygen in the water to decrease, thus impacting the aquatic life of the entire water body.
- 26. Reason This is caused by excessive quantities of chemicals which get washed from the fields. These act as nutrients for algae to flourish. Once these algae die, they serve as food for decomposers like bacteria. A lot of oxygen in the water body gets used up. This results in a decrease in the oxygen level which may kill aquatic organisms
- 27. Eutrophication The toxic chemicals from industries may change the color of water, increase the number of minerals called eutrophication, change the temperature of the water, and pose a severe hazard to water organisms The increased level of nutrients in water bodies is known as Eutrophication. It results in the bloom of algae in the water. It also depletes the amount of oxygen in the water that negatively affects fish and other aquatic animal populations.
- 28. Why does the increased level of nutrients in the water affect the survival of aquatic organisms?
- 29. Chemical /pesticides In order to protect their crops from bacteria and insects, farmers often use chemicals, and pesticides. When these substances seep into the groundwater, they can harm animals, plants and humans. Additionally, when it rains, the chemicals mix with rainwater, which then flows into rivers and streams that filter into the ocean, causing further water pollution
- 31. Ground water contamination The soil is also affected by impure water, causing changes in acidity, growth of worms, etc. chemicals dissolve in water and are washed into water bodies from the fields. They also seep into the ground to pollute ground water
- 32. Answer to this question Can ground water get polluted by sewage? How?
- 34. Effect of contaminated/Polluted water Water Pollution Affects Plant and Animal Life More Than 1,400 People Die From Water Pollution Daily Harmful effects of water pollution are Drinking polluted water – cause water born diseases like cholera, typhoid, jaundice. Polluted water in lakes and rivers – cause death of aquatic plants and animal due to oxygen depletion and harmful chemicals If we eat aquatic animals from polluted lakes and rivers, it can cause damage to our health and sometimes leads to death Water bodies with untreated industrial waste can damage our nervous system and causes diseases like blood poisoning and cancer It also results in the growth of algae in rivers and ponds which further harms the aquatic life
- 35. Answer to these questions What are the different ways in which water gets contaminated ?
- 36. Case study Ganga is one of the most famous rivers of India The Ganga River is the longest river in the country, running across a total length of 2,525 km, across large areas of Uttaranchal, Uttar Pradesh, Bihar and West Bengal. It passes through 9 states, supporting 29 Class I cities, 23 Class II cities, 48 towns and thousands of villages, serving around 400 million people. It sustains most of the northern, central and eastern Indian population. Millions of people depend on it for their daily needs and their daily needs and livelihood.
- 37. Endangered river World Wide Fund for Nature (WWF) found that Ganga is one of the ten most endangered rivers in the world. The pollution levels have been rising for many years. Reason: the towns and cities, through which the river flows, throw large quantities of garbage, untreated sewage, dead bodies, and many other harmful things, directly into the river. In fact the river is ‘dead’ at many places where the pollution levels are so high that aquatic life cannot survive
- 38. Polluted sketch of Ganga river The Ganga at Kanpur in Uttar Pradesh (U.P.), has one of the most polluted stretches of the river Kanpur is one of the most populated towns in U.P. People can be seen bathing, washing clothes and defecating in the river. They also throw garbage, flowers, idols of gods and goddesses and nonbiodegradable polythene bags into the river. At Kanpur the amount of water is comparatively small and the flow of the river is very slow. In addition, Kanpur has more than 5000 industries. These include fertiliser, detergent, leather and paint industries. These industrial units discharge toxic chemical wastes into the river.
- 39. Ganga Action Plan was launched in 1985. It aimed to reduce the pollution levels in the river. However, the increasing population and industrialisation have already damaged this mighty river beyond repair. Now, the Government of India has launched a new initiative known as National Mission for Clean Ganga (NMCG) in 2016.
- 40. Answer to these questions What are the factors responsible for pollution of the river ? What steps can be taken to restore the river Ganga to its past glory ? How would the disposal of garbage, etc., affect the living organisms in the river
- 41. Hot water can also be a pollutant ! This is usually water from power plants and industries. It is released into the rivers. It raises the temperature of the water body, adversely affecting the animals and plants living in it.
- 42. Clear, transparent water is always fit for drinking. Comment
- 44. What is Potable Water? Clear/Transparent Water may look clean without any dirt or insects But it may still contain many germs and microorganisms harmful to human health Potable water is water which has been purified to kil these germs Water which is suitable for drinking is called potable water 25% of the world’s population is without safe drinking water !
- 45. Difference Clean water Potable water It does not have any dirt but it may have germs and microorganisms It is free from any germs and microorganism It may not fit for drinking It is fit for drinking Example: wate used in Toilet Example: wate used in kitchen for making food
- 46. How water can be made safe for drinking: Use of house hold filters – Physical method of removing impurities In homes, different filters are used Example – Candle type filters Water is Boiled When water is boiled, it kills the germs in water Chlorination – Chemical method to purify water Chlorine tablets are added in water to make it safe to drink We should not use more chlorine tablets than specified.
- 47. How to prevent water pollution Laws for industrial units should be strictly implemented so that polluted water is not disposed off directly into rivers Create awareness – how to keep water clean Avoid Throwing of plastic to water bodies Keep water tanks and pipes clean Industry should process the water waste before throwing directly to the river use of disinfection Prohibiting open defecation in water resources
- 48. Never pour fat drippings (or any type of grease) down your drain or disposal. Never pour household chemicals down the drain or toilet. Do not use your toilet as a wastebasket. Avoid flushing anything down the toilet except toilet paper. Never flush old medications down the toilet. Use minimal detergent, or opt for an earth-friendly brand that is free from phosphates and sulfates. Minimize the use of pesticides, fertilizers, and herbicides. Never dispose of these down a nearby sewer drain. an
- 49. Industries Chemical waste should be first treated in waste treatment plants before throwing them in water Farmers Use more manures instead of fertilizers Festivals Idols of Gods and Goddesses can be made of Eco friendly substances which are soluble in water Homes We should try to recycle and resues water as much as possible For example water used for washing vegetables can be used to water plants in the garden We should use less polythenes
- 50. How to Save water . Save water and not waste it. Reduce, reuse and recycle should be our mantra ! Think of your daily routine – how can you save water?
- 54. Conclusion/key points to remember Pollution is no longer a distant phenomenon. It is affecting the quality hold tasks. For example of our daily lives. Unless we all realise our responsibility and start using environment-friendly processes, the very survival of our planet is in danger. Water is a precious natural resource. We must learn to conserve it
- 55. Points to remember/ Recap Water pollution is the contamination of water by substances harmful to life. Sewage, agricultural chemicals and industrial waste are some of the major contaminants of water. Water which is purified and fit for drinking is known as potable water. Water is a precious natural resource. We must learn to conserve it.
- 56. MCQ Why is heat called a pollutant of water? i) It causes water to boil, thus animals cannot drink it simultaneously ii) It causes water temperature to rise thus reducing the concentration of oxygen Only i Only ii Both i and ii None of the above
- 57. Which of the following diseases can be caused by drinking polluted water? Polio Diarrhoea Typhoid All of the above
- 58. Which of the following is considered a water pollutant? i) organic waste ii) Sediments iii) Heat i and ii ii and iii i, ii and iii i and iii Ans. c
- 59. Which of the following can be considered to be the primary source of pathogens in the water bodies? Domestic Sewage Industrial wastage Petroleum All of the above Ans. a