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Chapter 20 Water Pollution. Chapter Overview Questions What pollutes water, where do these pollutants come from, and what effects do they have? What pollutes.

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Presentation on theme: "Chapter 20 Water Pollution. Chapter Overview Questions What pollutes water, where do these pollutants come from, and what effects do they have? What pollutes."— Presentation transcript:

1 Chapter 20 Water Pollution

2 Chapter Overview Questions What pollutes water, where do these pollutants come from, and what effects do they have? What pollutes water, where do these pollutants come from, and what effects do they have? What are the major water pollution problems in streams and lakes? What are the major water pollution problems in streams and lakes? What causes groundwater pollution, and how can it be prevented? What causes groundwater pollution, and how can it be prevented?

3 Chapter Overview Questions (contd) What are the major water pollution problems affecting coastal waters & oceans? What are the major water pollution problems affecting coastal waters & oceans? How can we prevent and reduce surface water pollution? How can we prevent and reduce surface water pollution? How safe is drinking water, and how can it be made safer? How safe is drinking water, and how can it be made safer?

4 Case Study: Using Nature to Purify Sewage Ecological wastewater purification by a living machine. Ecological wastewater purification by a living machine. Uses the sun and a series of tanks containing plants, snails, zooplankton, crayfish, and fish (that can be eaten or sold for bait). Uses the sun and a series of tanks containing plants, snails, zooplankton, crayfish, and fish (that can be eaten or sold for bait). Water can be purified with UV or O 3 and consumed! Water can be purified with UV or O 3 and consumed! Figure 21-1 John Todd, Providence, RI

5 WATER POLLUTION: SOURCES, TYPES, AND EFFECTS Water pollution is any chemical, biological, or physical change in water quality that has a harmful effect on living organisms or makes water unsuitable for desired uses. Water pollution is any chemical, biological, or physical change in water quality that has a harmful effect on living organisms or makes water unsuitable for desired uses. Point source: specific location (drain pipes, ditches, sewer lines). Point source: specific location (drain pipes, ditches, sewer lines). Nonpoint source: cannot be traced to a single site of discharge (atmospheric deposition; agricultural / industrial / residential runoff) Nonpoint source: cannot be traced to a single site of discharge (atmospheric deposition; agricultural / industrial / residential runoff)

6 WATER POLLUTION: SOURCES Point source: specific location (drain pipes, ditches, sewer lines). Point source: specific location (drain pipes, ditches, sewer lines).

7 WATER POLLUTION: SOURCES Nonpoint source: cannot be traced to a single site of discharge (atmospheric deposition; agricultural / industrial / residential runoff) Nonpoint source: cannot be traced to a single site of discharge (atmospheric deposition; agricultural / industrial / residential runoff)

8 Table 21-2, p. 495 Biological Pollution: Pathogens in Water

9 Major Water Pollutants and Their Effects A fecal coliform bacteria test is used to indicate the likely presence of disease- causing bacteria in water. A fecal coliform bacteria test is used to indicate the likely presence of disease- causing bacteria in water. The standard for drinking water is zero fecal coliform colonies per culture! The standard for drinking water is zero fecal coliform colonies per culture! Figure 21-2

10 DO: Reduced by Degradeable Wastes, Heat, and Algae Growth from Excess Inorganic Nutrients Water quality and dissolved oxygen (DO) content in parts per million (ppm) at 20°C. Water quality and dissolved oxygen (DO) content in parts per million (ppm) at 20°C. Only a few fish species can survive in water less than 4 ppm at 20°C. Only a few fish species can survive in water less than 4 ppm at 20°C. Next

11 Dissolved Oxygen For most solutes (sugar, salt, etc): For most solutes (sugar, salt, etc): solubility increases as temperature increases solubility increases as temperature increases For DO: For DO: solubility decreases as temperature increases solubility decreases as temperature increases Next

12 Most solutes….

13 Dissolved Oxygen (DO)

14 Fig. 21-3, p. 496 Water Quality Below 4 Below 4.5 DO (ppm) at 20°C 4.5– –8 8–9 Gravely polluted Heavily polluted Moderately polluted Slightly polluted Good

15 Water Pollution Problems in Streams Dilution and decay of degradable, oxygen- demanding wastes and heat in a stream. Dilution and decay of degradable, oxygen- demanding wastes and heat in a stream. Next

16 Next Oxygen Sag Curve

17 POLLUTION OF FRESHWATER STREAMS Flowing streams can recover from a moderate level of degradable water pollutants if they are not overloaded and their flows are not reduced. Flowing streams can recover from a moderate level of degradable water pollutants if they are not overloaded and their flows are not reduced. In a flowing stream, the breakdown of degradable wastes by bacteria depletes DO and creates and oxygen sag curve. In a flowing stream, the breakdown of degradable wastes by bacteria depletes DO and creates and oxygen sag curve. This reduces or eliminates populations of organisms with high oxygen requirements.This reduces or eliminates populations of organisms with high oxygen requirements.

18 POLLUTION OF FRESHWATER STREAMS Most developed countries have sharply reduced point-source pollution but toxic chemicals and pollution from nonpoint sources are still a problem. Most developed countries have sharply reduced point-source pollution but toxic chemicals and pollution from nonpoint sources are still a problem. Stream pollution from discharges of untreated sewage and industrial wastes is a major problem in developing countries. Stream pollution from discharges of untreated sewage and industrial wastes is a major problem in developing countries % of raw sewage directly discharged into rivers in developing countries (!) % of raw sewage directly discharged into rivers in developing countries (!).

19 Stream Pollution in Developing Countries Water in many of central China's rivers are greenish black from uncontrolled pollution by thousands of factories.

20 Stream Pollution in Developing Countries

21 Case Study: Indias Ganges River: Religion, Poverty, and Health Religious beliefs, cultural traditions, poverty, and a large population interact to cause severe pollution of the Ganges River in India. Religious beliefs, cultural traditions, poverty, and a large population interact to cause severe pollution of the Ganges River in India. Very little of the sewage is treated. Very little of the sewage is treated. Hindu believe in cremating the dead to free the soul and throwing the ashes in the holy Ganges. Hindu believe in cremating the dead to free the soul and throwing the ashes in the holy Ganges. Some are too poor to afford the wood to fully cremate.Some are too poor to afford the wood to fully cremate. Decomposing bodies promote disease and depletes DO.Decomposing bodies promote disease and depletes DO.

22 Case Study: Indias Ganges River: Religion, Poverty, and Health Hindu funeral pyre

23 Decorated Funeral Pyre Incompletely burned bodies cause pollution.

24 Case Study: Indias Ganges River: Religion, Poverty, and Health Daily, more than 1 million Hindus in India bathe, drink from, or carry out religious ceremonies in the highly polluted Ganges River. Daily, more than 1 million Hindus in India bathe, drink from, or carry out religious ceremonies in the highly polluted Ganges River. Figure 21-6

25 Case Study: Indias Ganges River: Religion, Poverty, and Health

26

27

28 Indias Ganges River

29 Lakes

30 Lake George, NY

31

32 Overturn in Lakes

33 POLLUTION OF FRESHWATER LAKES Dilution of pollutants in lakes is less effective than in most streams because most lake water is not mixed well and has little flow. Dilution of pollutants in lakes is less effective than in most streams because most lake water is not mixed well and has little flow. Lakes and reservoirs are often stratified and undergo little mixing (Low DO in lower layers) Lakes and reservoirs are often stratified and undergo little mixing (Low DO in lower layers) Low flow makes them susceptible to runoff. Low flow makes them susceptible to runoff. Various human activities can overload lakes with plant nutrients, which decrease DO and kill some aquatic species. Various human activities can overload lakes with plant nutrients, which decrease DO and kill some aquatic species.

34 Cultural Eutrophication Eutrophication: the natural nutrient enrichment of a shallow lake, estuary or slow moving stream, mostly from runoff of plant nutrients from the surrounding land. Eutrophication: the natural nutrient enrichment of a shallow lake, estuary or slow moving stream, mostly from runoff of plant nutrients from the surrounding land. Cultural eutrophication: human activities accelerate the input of plant nutrients (mostly nitrate- and phosphate-containing effluents) to a lake. Cultural eutrophication: human activities accelerate the input of plant nutrients (mostly nitrate- and phosphate-containing effluents) to a lake. 85% of large lakes near major population centers in the U.S. have some degree of cultural eutrophication. 85% of large lakes near major population centers in the U.S. have some degree of cultural eutrophication.

35 Cultural Eutrophication Cultural Eutrophication of lakes causes sudden fish kills when DO drops due to Cultural Eutrophication of lakes causes sudden fish kills when DO drops due to 1. Overpopulated algae respiring at night without producing any O 2 via photosynthesis and/or 2. Bacteria respiring as they decompose dead overpopulated algae

36 Acid Rain in Freshwater Lakes

37 POLLUTION OF GROUNDWATER Groundwater can become contaminated with a variety of chemicals because it cannot effectively cleanse itself and dilute and disperse pollutants. Groundwater can become contaminated with a variety of chemicals because it cannot effectively cleanse itself and dilute and disperse pollutants. The drinking water for about half of the U.S. population and 95% of those in rural areas comes from groundwater. The drinking water for about half of the U.S. population and 95% of those in rural areas comes from groundwater.

38 Fig. 21-7, p. 501 Coal strip mine runoff Polluted air Deicing road salt Pesticides and fertilizers Hazardous waste injection well Pumping well Gasoline station Water pumping well Landfill Sewer Buried gasoline and solvent tanks Cesspool, septic tank Groundwater flow Confined aquifer Confined freshwater aquifer Unconfined freshwater aquifer Accidental spills Waste lagoon Leakage from faulty casing Discharge

39 POLLUTION OF GROUNDWATER One way to think about waste: degradability One way to think about waste: degradability Degradable wastes (urine & fecal matter, dead leaves, food waste) Degradable wastes (urine & fecal matter, dead leaves, food waste) Nondegradable wastes (lead, mercury, arsenic, flouride) are there permanently. Nondegradable wastes (lead, mercury, arsenic, flouride) are there permanently. Slowly degradable wastes (such as DDT and PCBs) are there for decades. Slowly degradable wastes (such as DDT and PCBs) are there for decades. It can take hundreds to thousands of years for contaminated groundwater to cleanse itself of degradable wastes. It can take hundreds to thousands of years for contaminated groundwater to cleanse itself of degradable wastes.

40 Fig. 21-8, p. 502 Aquifer Water well Migrating vapor phase Contaminant plume moves with the groundwater Free gasoline dissolves in groundwater (dissolved phase) Groundwater flow Water table Gasoline leakage plume (liquid phase) Leaking tank Bedrock

41 POLLUTION OF GROUNDWATER Over the 21 st century, scientists expect to find many millions of leaking underground storage tanks to become a major global health problem. Over the 21 st century, scientists expect to find many millions of leaking underground storage tanks to become a major global health problem.

42 POLLUTION OF GROUNDWATER Leaks from a number of sources have contaminated groundwater in parts of the world. Leaks from a number of sources have contaminated groundwater in parts of the world. According the the EPA, one or more organic chemicals contaminate about 45% of municipal groundwater supplies. According the the EPA, one or more organic chemicals contaminate about 45% of municipal groundwater supplies. By 2003, the EPA had completed the cleanup of 297,000 of 436,000 underground tanks leaking gasoline, diesel fuel, home heating oil, or toxic solvents. By 2003, the EPA had completed the cleanup of 297,000 of 436,000 underground tanks leaking gasoline, diesel fuel, home heating oil, or toxic solvents.

43 Case Study: Arsenic in Groundwater - a Natural Threat Toxic Arsenic (As) can naturally occur at high levels in soil and rocks. Toxic Arsenic (As) can naturally occur at high levels in soil and rocks. Drilling into aquifers can release As into drinking water supplies. Drilling into aquifers can release As into drinking water supplies. According to WHO, more than 112 million people are drinking water with As levels times the 10 ppb standard. According to WHO, more than 112 million people are drinking water with As levels times the 10 ppb standard. Mostly in Bangladesh, China, and West Bengal, India. Mostly in Bangladesh, China, and West Bengal, India.

44 Fig. 21-9, p. 504 Solutions Groundwater Pollution CleanupPrevention Find substitutes for toxic chemicals Install monitoring wells near landfills and underground tanks Require leak detectors on underground tanks Ban hazardous waste disposal in landfills and injection wells Store harmful liquids in aboveground tanks with leak detection and collection systems Pump to surface, clean, and return to aquifer (very expensive) Pump nanoparticles of inorganic compounds to remove pollutants (may be the cheapest, easiest, and most effective method but is still being developed) Keep toxic chemicals out of the environment Inject microorganisms to clean up contamination (less expensive but still costly)

45 OCEAN POLLUTION The abyssal/benthic zones of open oceans, if they are not overloaded, can disperse and break down large quantities of degradable pollutants. The abyssal/benthic zones of open oceans, if they are not overloaded, can disperse and break down large quantities of degradable pollutants.

46 OCEAN POLLUTION But pollution of coastal waters near heavily populated areas is a serious problem. But pollution of coastal waters near heavily populated areas is a serious problem. About 40% of the worlds population lives within 160 miles of the coast. About 40% of the worlds population lives within 160 miles of the coast. The EPA has classified 4 of 5 estuaries as threatened or impaired. The EPA has classified 4 of 5 estuaries as threatened or impaired.

47 Fig , p. 505 HEALTHY ZONES Clear, oxygen-rich waters promote growth of plankton and sea grasses, and support fish. O 2 DEPLETION ZONE Sedimentation and algae overgrowth reduce sunlight, kill beneficial sea grasses, use up oxygen, and degrade habitat. RED TIDES Excess nitrogen causes explosive growth of toxicmicroscopic algae, poisoning fish and marine mammals. FARMS Runoff of pesticides, manure, and fertilizers adds toxins and excess nitrogen and phosphorus. TOXIC SEDIMENTS Chemicals and toxic metals contaminate shellfish beds, kill spawning fish, and accumulate in the tissues of bottom feeders. CONSTRUCTION SITES Sediments are washed into waterways, choking fish and plants, clouding waters, and blocking sunlight. URBAN SPRAWL Bacteria and viruses from sewers and septic tanks contaminate shellfish beds Oxygen-depleted zone Closed beach CITIES Toxic metals and oil from streets and parking lots pollute waters; INDUSTRY Nitrogen oxides from autos and smokestacks, toxic chemicals, and heavy metals in effluents flow into bays and estuaries. Closed shellfish beds

48 OCEAN POLLUTION Harmful algal blooms (HAB) are caused by explosive growth of harmful algae from sewage and agricultural runoff. Harmful algal blooms (HAB) are caused by explosive growth of harmful algae from sewage and agricultural runoff. Figure 21-11

49 HABs Harmful Algae Blooms Red tide Red tide Figure 21-11

50 Oxygen Depletion in the Northern Gulf of Mexico A large zone of oxygen- depleted water (dead zone) forms for half of the year in the Gulf of Mexico as a result of HAB. A large zone of oxygen- depleted water (dead zone) forms for half of the year in the Gulf of Mexico as a result of HAB. Next

51 Fig. 21-A, p. 507 Mississippi River Mississippi River Basin Gulf of Mexico Ohio River Mississippi River Missouri River TX MS LA Depleted oxygen LOUISIANA Gulf of Mexico

52 Figure Chesapeake Bay

53 Case Study: The Chesapeake Bay – An Estuary in Trouble Pollutants from six states contaminate the shallow estuary, but cooperative efforts have reduced some of the pollution inputs. Pollutants from six states contaminate the shallow estuary, but cooperative efforts have reduced some of the pollution inputs. Figure 21-12

54 OCEAN OIL POLLUTION Most ocean oil pollution comes from human activities on land. Most ocean oil pollution comes from human activities on land. Studies have shown it takes about 3 years for many forms of marine life to recover from large amounts of crude oil (oil directly from ground). Studies have shown it takes about 3 years for many forms of marine life to recover from large amounts of crude oil (oil directly from ground). Recovery from exposure to refined oil (fuel oil, gasoline, etc…) can take years for marine life to recover. Recovery from exposure to refined oil (fuel oil, gasoline, etc…) can take years for marine life to recover.

55 OCEAN OIL POLLUTION Tanker accidents and blowouts at offshore drilling rigs can be extremely devastating to marine life (especially diving birds, left). Tanker accidents and blowouts at offshore drilling rigs can be extremely devastating to marine life (especially diving birds, left). Figure 21-13

56 OCEAN OIL POLLUTION Exxon Valdez oil spill: Exxon Valdez oil spill: March 24, 1989 March 24, 1989 Prince William Sound, Alaska Prince William Sound, Alaska Single-wall oil tanker runs aground Single-wall oil tanker runs aground 10.8 million gallons of crude oil spilled 10.8 million gallons of crude oil spilled Captain was drunk Captain was drunk One of the worst single environmental disasters in US history One of the worst single environmental disasters in US history

57 Exxon Valdez

58

59 In 1994, a jury awarded plaintiffs $287 million in compensatory damages and $5 billion in punitive damages. Exxon appealed and the Ninth Circuit court reduced the punitive damages to $2.5 billion. Exxon then appealed the punitive damages to the Supreme Court which capped the damages to $507.5 million in June, On August 27, 2008, Exxon Mobil agreed to pay 75% of the $507.5 million damages ruling to settle the 1989 Exxon Valdez oil spill off AlaskaAugust In June 2009, a federal ruling ordered Exxon to pay an additional $480 million in interest on their delayed punitive damage awards

60 But Remember… Most ocean oil pollution comes from human activities on land. Most ocean oil pollution comes from human activities on land. Oceanic oil pollution has been considered a low-risk environmental problem… Until April of 2010…

61 BPs Deepwater Horizon Oil Spill

62 April 20, 2010, explosion of Deepwater Horizonexplosion of Deepwater Horizon 11 killed, 17 others injured July 15, 2010, the leak was partially capped 4.9 million barrels (780,000 m 3 ) of crude oil released = million gallons of crude (almost 30x the Exxon Valdez)crude oil On September 19, 2010, the relief well process was successfully completed

63 BPs Deepwater Horizon Oil Spill

64

65

66

67 Fig , p. 509 Reduce input of toxic pollutants Solutions Coastal Water Pollution PREVENTIONCLEANUP Use wetlands, solar-aquatic, or other methods to treat sewage Require at least secondary treatment of coastal sewage Sprinkle nanoparticles over an oil or sewage spill to dissolve the oil or sewage without creating harmful by-products (still under development) Improve oil-spill cleanup capabilities Recycle used oil Regulate coastal development Protect sensitive areas from development, oil drilling, and oil shipping Ban ocean dumping of sludge and hazardous dredged material Ban dumping of wastes and sewage by maritime and cruise ships in coastal waters Separate sewage and storm lines Require double hulls for oil tankers

68 The key to reducing nonpoint pollution – most of it from agriculture – is to prevent it from reaching bodies of water. Farmers can reduce runoff by The key to reducing nonpoint pollution – most of it from agriculture – is to prevent it from reaching bodies of water. Farmers can reduce runoff by Planting buffers Planting buffers Using low-till & no-till techniques Using low-till & no-till techniques Keeping cropland covered with vegetation Keeping cropland covered with vegetation Using no fertilizer on steep land Using no fertilizer on steep land Locate feedlots well away from water Locate feedlots well away from water USA: Successful on Point Sources, Working on Non-point Sources

69 PREVENTING AND REDUCING SURFACE WATER POLLUTION Most developed countries use laws to set water pollution standards, but such laws rarely exist in developing countries. Most developed countries use laws to set water pollution standards, but such laws rarely exist in developing countries. The U.S. Clean Water Act (1972) sets standards for allowed levels of key water pollutants and requires polluters to get permits. The U.S. Clean Water Act (1972) sets standards for allowed levels of key water pollutants and requires polluters to get permits. EPA is experimenting with a discharge trading policy similar to cap & trade for air pollution control. EPA is experimenting with a discharge trading policy similar to cap & trade for air pollution control.

70 Reducing Water Pollution through Sewage Treatment Septic tanks and various levels of sewage treatment can reduce point-source water pollution. Septic tanks and various levels of sewage treatment can reduce point-source water pollution. Figure 21-15

71 Fig , p. 510 Distribution box Manhole cover (for cleanout) Vent pipe Perforated pipe Drain field (gravel or crushed stone) Septic tank Sludge Wastewater Gas Scum

72 Reducing Water Pollution through Sewage Treatment Primary and Secondary sewage treatment. Primary and Secondary sewage treatment. Figure 21-16

73 Fig , p. 511 Raw sewage from sewers Activated sludge Disposed of in landfill or ocean or applied to cropland, pasture, or rangeland Primary TreatmentSecondary Treatment Grit chamberBar screenSettling tankAeration tankSettling tank Chlorine disinfection tank Sludge drying bed Sludge digester Air pump To river, lake, or ocean (kills bacteria) Sludge Physical ProcessesBiological Processes

74 Reducing Water Pollution through Sewage Treatment Raw sewage reaching a municipal sewage treatment plant typically undergoes: Raw sewage reaching a municipal sewage treatment plant typically undergoes: Primary sewage treatment: a physical process that uses screens and a grit tank to remove large floating objects and allows settling (sludge!) Primary sewage treatment: a physical process that uses screens and a grit tank to remove large floating objects and allows settling (sludge!) Secondary sewage treatment: a biological process in which aerobic bacteria remove as much as 90% of dissolved and biodegradable, oxygen demanding organic wastes. Secondary sewage treatment: a biological process in which aerobic bacteria remove as much as 90% of dissolved and biodegradable, oxygen demanding organic wastes.

75 Reducing Water Pollution through Sewage Treatment Advanced or tertiary sewage treatment: Advanced or tertiary sewage treatment: Uses series of chemical and physical processes to remove specific pollutants left over (especially nitrates and phosphates). Uses series of chemical and physical processes to remove specific pollutants left over (especially nitrates and phosphates). Water is chlorinated to remove coloration and to kill disease-carrying bacteria and some viruses (disinfect). Water is chlorinated to remove coloration and to kill disease-carrying bacteria and some viruses (disinfect). Ozone or UV light may also be used to sanitize sewage treatment effluent Ozone or UV light may also be used to sanitize sewage treatment effluent

76 Reducing Water Pollution through Sewage Treatment Sewage sludge can be used as a soil conditioner but this can cause health problems if it contains infectious bacteria and/or toxic chemicals. Sewage sludge can be used as a soil conditioner but this can cause health problems if it contains infectious bacteria and/or toxic chemicals. Preventing toxic chemicals from reaching sewage treatment plants would eliminate such chemicals from the sludge and water discharged from such plants. Preventing toxic chemicals from reaching sewage treatment plants would eliminate such chemicals from the sludge and water discharged from such plants.

77 Fig , p. 513 Sludge Groundwater Contamination Harmful chemicals and pathogens may leach into groundwater and shallow wells. Odors Odors may cause illness or indicate presence of harmful gases. Livestock Poisoning Cows may die after grazing on sludge-treated fields. Dust Particles Particles of dried sludge carry viruses and harmful bacteria that can be inhaled, infect cuts or enter homes. Surface Runoff Harmful chemicals and pathogens may pollute nearby streams,lakes, ponds, and wetlands. Exposure Children may walk or play in fertilized fields. BUFFER ZONE

78 Humboldt County, California decided to treat wastewater as a resource rather than a problem, and built the Arcata Marsh and Wildlife Sanctuary. The marsh relies on natural systems to filter the citys sewage.

79 Reducing Water Pollution through Sewage Treatment Natural and artificial wetlands and other ecological systems can be used to treat sewage. Natural and artificial wetlands and other ecological systems can be used to treat sewage. California created a 65 hectare wetland near Humboldt Bay that acts as a natural wastewater treatment plant for the town of 16,000 people. California created a 65 hectare wetland near Humboldt Bay that acts as a natural wastewater treatment plant for the town of 16,000 people. The project cost less than half of the estimated price of a conventional treatment plant. The project cost less than half of the estimated price of a conventional treatment plant.

80 Reducing Water Pollution through Sewage Treatment Water pollution laws have significantly improved water quality in many U.S. streams and lakes but there is a long way to go. Water pollution laws have significantly improved water quality in many U.S. streams and lakes but there is a long way to go. Some want to strengthen the U.S. Clean Water Act (CWA) to prevent rather than focusing on end-of-the-pipe removal. Some want to strengthen the U.S. Clean Water Act (CWA) to prevent rather than focusing on end-of-the-pipe removal. Many farmers and developers see the CWA as limiting their rights as property owners to fill in wetlands. Many farmers and developers see the CWA as limiting their rights as property owners to fill in wetlands.

81 DRINKING WATER QUALITY Centralized water treatment plants and… Centralized water treatment plants and… watershed protection can provide safe drinking water for city dwellers in developed countries. watershed protection can provide safe drinking water for city dwellers in developed countries.

82 Watering the Big Apple (NYC) 90% of NYC water comes from the Catskill Mountains in upstate New York 90% of NYC water comes from the Catskill Mountains in upstate New York

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84 Water for NYC NYC faced a $6 billion upgrade to build water purification facilities NYC faced a $6 billion upgrade to build water purification facilities Instead, NYC negotiated a $1.5 billion, 10 yr agreement with towns, farmers, & NY state to protect & restore forests, wetlands, & streams in the Catskills watershed. Instead, NYC negotiated a $1.5 billion, 10 yr agreement with towns, farmers, & NY state to protect & restore forests, wetlands, & streams in the Catskills watershed. Savings realized by relying on natural purification: $4.5 billion, PLUS $300 million per year saved in filtration costs Savings realized by relying on natural purification: $4.5 billion, PLUS $300 million per year saved in filtration costs

85 DRINKING WATER QUALITY Simpler and cheaper ways can be used to purify drinking water for developing countries. Simpler and cheaper ways can be used to purify drinking water for developing countries. Exposing water to heat and the suns UV rays in a plastic bottle for 3 hours can kill infectious microbes. Exposing water to heat and the suns UV rays in a plastic bottle for 3 hours can kill infectious microbes. 30%-40% reduction in dangerous childhood diarrhea. 30%-40% reduction in dangerous childhood diarrhea. Lifestraws Lifestraws Inexpensive UV exposure facilities (per FLOW video) Inexpensive UV exposure facilities (per FLOW video) In the works: handheld carbon nanotube filters In the works: handheld carbon nanotube filters

86 Lifestraws in Action

87 LifeStraw Personal filters a minimum of 700 litres of water, enough for one person for one year. LifeStraw Family filters a minimum of 18,000 litres of water, providing safe drinking water for a family for more than two years. It removes % of waterborne bacteria, 99.99% of viruses, and 99.9% of parasites. bacteriavirusesparasites

88 Using Laws to Protect Drinking Water While most developed countries have drinking water quality standards and laws, most developing countries do not. While most developed countries have drinking water quality standards and laws, most developing countries do not. The U.S Safe Drinking Water Act requires the EPA to establish national drinking water standards (maximum contaminant levels) for any pollutant that may have adverse effects on human health. The U.S Safe Drinking Water Act requires the EPA to establish national drinking water standards (maximum contaminant levels) for any pollutant that may have adverse effects on human health.

89 Using Laws to Protect Drinking Water The U.N. estimates that 5.6 million Americans drink water that does not meet EPA standards. The U.N. estimates that 5.6 million Americans drink water that does not meet EPA standards. 1 in 5 Americans drinks water from a treatment plant that violated one or more safety standard. 1 in 5 Americans drinks water from a treatment plant that violated one or more safety standard. Industry pressures to weaken the Safe Drinking Act: Industry pressures to weaken the Safe Drinking Act: Eliminate national tests and public notification of violations. Eliminate national tests and public notification of violations. Allow rights to pollute if provider cannot afford to comply. Allow rights to pollute if provider cannot afford to comply.

90 Is Bottled Water the Answer? Some bottled water is often not as pure as tap water and costs much more. Some bottled water is often not as pure as tap water and costs much more. 40% of bottled water is contaminated with bacteria and/or fungi 40% of bottled water is contaminated with bacteria and/or fungi 1.4 million metric tons of plastic bottles are thrown away per year. 1.4 million metric tons of plastic bottles are thrown away per year. Fossil fuels are used to make plastic bottles. Fossil fuels are used to make plastic bottles. The oil used to produce plastic bottles in the U.S. each year would fuel 100,000 cars.The oil used to produce plastic bottles in the U.S. each year would fuel 100,000 cars.

91 Fig , p. 517 Prevent groundwater contamination Solutions Water Pollution Reduce birth rates Reduce poverty Reduce air pollution Practice 5 R's of resource use (refuse, reduce, recycle, reuse, repurpose) Work with nature to treat sewage Find substitutes for toxic pollutants Reuse treated wastewater for irrigation (purple pipe) Reduce nonpoint runoff

92 Fig , p. 517 What Can You Do? Water Pollution Fertilize garden and yard plants with manure or compost instead of commercial inorganic fertilizer. Minimize your use of pesticides. Do not apply fertilizer or pesticides near a body of water. Grow or buy organic foods. Do not drink bottled water unless tests show that your tap water is contaminated. Merely refill and reuse plastic or stainless steel bottles with tap water. Compost your food wastes. Do not use water fresheners in toilets. Do not flush unwanted medicines down the toilet. DO NOT POUR pesticides, paints, solvents, oil, antifreeze, or other products containing harmful chemicals down the drain or onto the ground.


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