1. Water Pollution
Chapter 20

2. The Seattle, Washington Area, U.S.

3. Core Case Study: Lake Washington
Sewage dumped into Lake Washington
1955: Edmondson discovered cyanobacteria (blue/green algae) in the lake
Role of phosphorus, increased cyanbobacteria
Public pressure led to cleanup of the lake, diverted to Puget Sound
New pollution challenges

4. Kayaker Enjoys Lake Washington

5. 20-1 What Are the Causes and Effects of Water Pollution?
Concept 20-1A Water pollution causes illness and death in humans and other species and disrupts ecosystems.
Concept 20-1B The chief sources of water pollution are agricultural activities, industrial facilities, and mining, but growth in population and resource use make it increasingly worse.

6. Water Pollution Comes from Point and Nonpoint Sources (1)
Water pollution: any chemical, biological, or physical change in water quality that harms living organisms
Point sources
Located at specific places
Easy to identify, monitor, and regulate
Examples: Factories, sewage treatment plants, underground mines, & oil tankers

7. Water Pollution Comes from Point and Nonpoint Sources (2)
Broad, diffuse areas
Difficult to identify and control
Expensive to clean up & identify
Examples

8. Water Pollution Comes from Point and Nonpoint Sources (3)
Agriculture activities: leading cause of water pollution
Sediment eroded from the lands
Fertilizers and pesticides
Bacteria from livestock and food processing wastes
Industrial facilities: inorganic & organic chemicals
Mining: surface, sediments erode & toxic chemical runoff

9. Water Pollution Comes from Point and Nonpoint Sources (4)
Other sources of water pollution
Parking lots: grease, toxic metals & sediments collect on impervious surfaces
Also disrupt hydrological cycle, it can increase local flooding & erosion
Human-made materials
E.g., plastics
Climate change due to global warming
Drought: will decrease river flows that dilute wastes
Intense downpours will flush more chemicals, plant nutrients, & microorganisms into waterways

10. Point Source of Polluted Water in Gargas, France

11. Nonpoint Sediment from Unprotected Farmland Flows into Streams

12. Major Water Pollutants Have Harmful Effects
Infectious disease organisms: contaminated drinking water
The World Health Organization (WHO)
3 Million people die every year, mostly under the age of 5

13. Major Water Pollutants and Their Sources

14. Common Diseases Transmitted to Humans through Contaminated Drinking Water

15. Science Focus: Testing Water for Pollutants (1)
Variety of tests to determine water quality:
Coliform bacteria: Escherichia coli, significant levels: drinking per 100mL no colonies, swimming per 100mL no more than 200, raw sewage several million colonies
Level of dissolved oxygen (DO)
Chemical analysis: EB Shurts Center

16. Science Focus: Testing Water for Pollutants (2)
Indicator species
Examples: cattails in areas with fuels, solvents, & other organic chemicals can be analyzed to determine exact pollutants
Bacteria and yeast glow in the presence of a particular toxic chemical
Color and turbidity of the water: Measures Cloudiness

17. Discussion Question 1
How does the process of algae blooms lower dissolved oxygen?

18. Water Quality as Measured by Dissolved Oxygen Content in Parts per Million

19. 20-2 What Are the Major Water Pollution Problems in Streams and Lakes?
Concept 20-2A While streams are extensively polluted worldwide by human activities, they can cleanse themselves of many pollutants if we do not overload them or reduce their flows.
Concept 20-2B Addition of excessive nutrients to lakes from human activities can disrupt lake ecosystems, and prevention of such pollution is more effective and less costly than cleaning it up.

20. Streams Can Cleanse Themselves If We Do Not Overload Them
Dilution
Biodegradation of wastes by bacteria takes time
Doesn’t work when overloaded with pollutants or when drought, damming, or water diversions reduce flow
Does not eliminate slowly degradable & non-degradable pollutants
Oxygen sag curve: breakdown of biodegradable wastes by bacteria depletes dissolved oxygen

21. Dilution and Decay of Degradable, Oxygen-Demanding Wastes in a Stream

22. Stream Pollution in Developed Countries
1970s: Water pollution control laws: increased the number & quality of wastewater treatment plants in U.S., required industries to reduce or eliminate their point-source discharge
Successful water clean-up stories
Ohio Cuyahoga River, U.S. (once so polluted it caught on fire)
Thames River, Great Britain (1950’s it was a smelly sewer)
Contamination of toxic inorganic and organic chemicals by industries and mines

23. Individuals Matter: The Man Who Planted Trees to Restore a Stream
John Beal: restoration of Hamm Creek, Seattle, WA, U.S.
Planted trees
Persuaded companies to stop dumping
Removed garbage

24. Global Outlook: Stream Pollution in Developing Countries
Half of the world’s 500 rivers are polluted, most run through developing countries
Untreated sewage
80-90% of developing country cities discharge directly into water
Industrial waste
Increase sewage
India’s rivers
2/3 are polluted
China’s rivers
1/3 judged unfit for agriculture & industrial use

25. Girl Sits on the Edge of a Road beside a Stream Loaded with Raw Sewage in Iraq

26. Natural Capital Degradation: Highly Polluted River in China

27. Trash Truck Disposing of Garbage into a River in Peru

28. Case Study: India’s Ganges River: Religion, Poverty, Population Growth, and Health (1)
Holy river: religious customs
Sewage
Human remains: cremated & ashes thrown (belief that it increases chances of soul getting into heaven)
Use wood fires, many cannot afford wood so unburned or partially burnt bodies are dumped (do the same for livestock)
Government intervention
Waste treatment plants
Crematoriums
Introduced snapping turtles to devour corpses

29. Case Study: India’s Ganges River: Religion, Poverty, Population Growth, and Health (2)
Adding to the pollution
Religious custom
Painted statues
Paints & coatings contain toxic metals
Global warming
Gangotri Glacier: melting at an accelerated rate

30. India’s Ganges River

31. Discussion Question 2
What arguments (give at least 2 well thought out) would you use to convince someone to use a newer, cleaner technology for observing an ancient religious ritual in order to help protect the Ganges River?

32. Low Water Flow and Too Little Mixing Makes Lakes Vulnerable to Water Pollution
Less effective at diluting pollutants than streams
Stratified layers
Little vertical mixing
Little or no water flow
More vulnerable to contamination by runoff, discharge of plant nutrients, oil, pesticides, lead, mercury, selenium
DDT & PCB’s Poly Chlorinated Biphenyls (chlorine containing organic compounds were used as lubricants, hydraulic fluids, electrical insulators, paints, fire retardants, preservatives, adhesives, pesticides)
Banned in 1977 for domestic production

33. Cultural Eutrophication Is Too Much of a Good Thing (1)
Eutrophication: natural nutrient enrichment from runoff of nitrates & phosphates
Oligotrophic lake
Low nutrients, clear water
Cultural eutrophication: human activities increase nitrate & phosphate

34. Cultural Eutrophication Is Too Much of a Good Thing (2)
During hot weather or droughts
Algal blooms
Increased bacteria
More nutrients
Anaerobic bacteria
Then what?
When algae die they are decomposed by population of aerobic bacteria, deplete of Oxygen
If excess nutrients continue to flow into a lake anaerobic bacteria take over & produce smelly, highly toxic Hydrogen sulfide & flammable methane

35. Cultural Eutrophication Is Too Much of a Good Thing (3)
Prevent or reduce cultural eutrophication
Remove nitrates and water treatment facilities
Diversion of lake water
Ban or limit the use of phosphates in detergents, soil conservation, limit runoff
Clean up lakes
Remove excess weeds
Use herbicides and algaecides; down-side?
Pump in air: increase dissolved oxygen

36. Revisiting Lake Washington and Puget Sound
Severe water pollution can be reversed: by sharply decreasing inputs
Citizen action combined with scientific research: bottom up philosophy
Good solutions may not work forever
Wastewater treatment plant effluents sent into Puget Sound
Now what’s happening?
Population growth
Resource Use
Urbanization

37. Case Study: Pollution in the Great Lakes (1)
1960s: Many areas with cultural eutrophication
1972: Canada and the United States: Great Lakes pollution control program
New/upgraded sewage treatment plants
Better treatment of industrial wastes
Bans on detergents/household cleaners & water conditioners with phosphates
Problems still exist
Raw sewage
Nonpoint runoff of pesticides and fertilizers:urban sprawl
Biological pollution:zebra mussels
Atmospheric deposition of pesticides and Hg: coal burning power plants
¼ of fish are unsafe for human consumption

38. Case Study: Pollution in the Great Lakes (2)
2007 State of the Great Lakes report
New pollutants found: polybrominated diphenyl ethers found in flame retardants, pharmaceuticals & personal care products
Wetland loss and degradation; significance?
Declining of some native species
Native carnivorous fish species declining
What should be done?
Prevention
Ex. Ban the use of bleach used in pulp & paper industry

39. Discussion Question 3
What are 3 steps you would take to sharply reduce pollution in the Great Lakes?

40. The Great Lakes of North America

41. 20-3 Pollution Problems Affecting Groundwater, Other Water Sources
Concept 20-3A Chemicals used in agriculture, industry, transportation, and homes can spill and leak into groundwater and make it undrinkable.
Concept 20-3B There are simple ways and complex ways to purify drinking water, but protecting it through pollution prevention is the least expensive and most effective strategy.

42. Ground Water Cannot Cleanse Itself Very Well (1)
Source of drinking water
Common pollutants
Fertilizers and pesticides
Gasoline
Organic solvents
Pollutants dispersed in a widening plume

43. Ground Water Cannot Cleanse Itself Very Well (2)
Slower chemical reactions in groundwater due to
Slow flow: contaminants not diluted
Less dissolved oxygen
Fewer decomposing bacteria (cold temperatures)
How long will it take to cleans itself of
Slowly degradable wastes (take 1,000s of years)
E.g., DDT
Nondegradable wastes (on a human time scale, remain permanently
E.g., Pb and As

44. Principal Sources of Groundwater Contamination in the U.S.

45. Groundwater Contamination from a Leaking Gasoline Tank

46. Groundwater Pollution Is a Serious Threat
China: many contaminated or overexploited aquifers, supplies 70% of drinking water
U.S.: FDA reports of toxins found in many aquifers, 2/3 of liquid hazardous wastes are injected into deep disposal wells, some leak into aquifers
What about leaking underground storage tanks:
Gasoline
Oil
Methyl tertiary butyl ether (MTBE), gasoline additive, carcinogen ~250,000 leaking gas tanks by 1990’s
Nitrate ions: from fertilizers
Wastes we think we have thrown away or stored can come back: there is no ‘away’

47. Case Study: A Natural Threat from Arsenic in Groundwater
Source of As in the groundwater
Mining & ore processing 10 ppb
Human health hazards: cancer
Skin
Lungs
Bladder
2006 research: Rice University, TX, U.S.
Purification system to remove As

48. Pollution Prevention Is the Only Effective Way to Protect Groundwater
Prevent contamination of groundwater
Cleanup: expensive and time consuming
Must be pumped, cleaned, & returned

49. Solutions: Groundwater Pollution, Prevention and Cleanup

50. There Are Many Ways to Purify Drinking Water
Reservoirs and purification plants: increase dissolved oxygen & allow suspended matter to settle, then pumped to a purification plant
Process sewer water to drinking water: we have the technology to do so
Expose clear plastic containers to sunlight (UV): kills infectious microbes
Nanofilters
The LifeStraw: eliminates viruses & parasites

51. The LifeStraw: Personal Water Purification Device

52. Case Study: Protecting Watersheds Instead of Building Water Purification Plants
New York City water
Reservoirs in the Catskill Mountains: underground tunnels transport water to the city
Protect the watershed instead of water purification plants

53. Discussion Question 4
Where does New Berlin get its drinking water? How could New Berlin save money and help protect biodiversity?

54. Using Laws to Protect Drinking Water Quality
1974: U.S. Safe Drinking Water Act
Sets maximum contaminant levels for any pollutants that affect human health
1 out of 5 American’s drink water supplied by a wastewater plant that has violated one or more safety standards during part of a year
Health scientists: strengthen the law
Combine systems, notify public of offenders, ban lead in new pipes
Water-polluting companies: weaken the law
Eliminate national tests & public notifications
Give waivers
Eliminate the requirement that water systems use affordable, feasible technology to remove carcinogens

55. Is Bottled Water the Answer?
U.S.: some of the cleanest drinking water
Bottled water
Some from tap water~1/4 not as high qualityas tap water
40% bacterial contamination
Fuel cost to manufacture the plastic bottles
Recycling of the plastic
Toxic gases & liquids are released during the manufacturing of bottles
Growing back-to-the-tap movement

56. 20-4 What Are the Major Water Pollution Problems Affecting Oceans?
Concept 20-4A The great majority of ocean pollution originates on land and includes oil and other toxic chemicals and solid wastes, which threaten aquatic species and other wildlife and disrupt marine ecosystems.
Concept 20-4B The key to protecting the oceans is to reduce the flow of pollutants from land and air and from streams emptying into these waters.

57. Ocean Pollution Is a Growing and Poorly Understood Problem (1)
2006: State of the Marine Environment
80% of marine pollution originates on land
Sewage:80-90% of municipal sewage from coastal developing countries & some developed are dumped untreated
Coastal areas most affected
Deeper ocean waters: we don’t know the effects
Dilution
Dispersion
Degradation

58. Ocean Pollution Is a Growing and Poorly Understood Problem (2)
Cruise line pollution: what is being dumped?
Perchloroethylene & benzene
Plastic garbage & waste oil
U.S. coastal waters
Raw sewage: illegal but still done
Sewage and agricultural runoff: NO3- and PO43-
Harmful algal blooms: red, brown, or green toxic tides
Oxygen-depleted zones
Dead zones, hypoxia

59. Residential Areas, Factories, and Farms Contribute to Pollution of Coastal Waters

60. Discussion Question 5
Should we dump sewage sludge and other harmful pollutants into the deep ocean? Explain why or why not.

61. A Red Tide

62. Science Focus: Oxygen Depletion in the Northern Gulf Of Mexico
Severe cultural eutrophication
Oxygen-depleted zone
Overfertilized coastal area
Preventive measures
Will it reach a tipping point?

63. A Large Zone of Oxygen-Depleted Water in the Gulf of Mexico Due to Algal Blooms

64. Ocean Oil Pollution Is a Serious Problem (1)
Crude and refined petroleum
Highly disruptive pollutant
Largest source of ocean oil pollution
Urban and industrial runoff from land
Oil spills get more press
1989: Exxon Valdez, oil tanker
2002: Prestige, oil tanker twice the amount of Exxon

65. Ocean Oil Pollution Is a Serious Problem (2)
Volatile organic hydrocarbons (VOC’s)
Kill many aquatic organisms, in larval forms
Tar-like globs on the ocean’s surface
Coat animals
Heavy oil components sink
Affect the bottom dwellers

66. Ocean Oil Pollution Is a Serious Problem (3)
Faster recovery from crude oil than refined oil
Crude, 3 years
Refined years
Cleanup procedures ~15% of oil
Floating booms
Skimmer boats
Absorbent devices (feathers, hair)
Chemical fire
Bacteria
Methods of preventing oil spills

67. Solutions: Coastal Water Pollution, Prevention and Cleanup

68. Discussion Question 6
Which two of the previous solutions do you think are the most important? Why?

69. 20-5 How Can We Best Deal with Water Pollution?
Concept Reducing water pollution requires preventing it, working with nature to treat sewage, cutting resource use and waste, reducing poverty, and slowing population growth.

70. We Need to Reduce Surface Water Pollution from Nonpoint Sources (1)
Reduce erosion
Keep cropland covered with vegetation
Reduce the amount of fertilizers: slow release or no fertilizer, none on steep slopes
Plant buffer zones of vegetation
Use organic farming techniques: manure

71. We Need to Reduce Surface Water Pollution from Nonpoint Sources (2)
Use pesticides prudently (only when needed)
Control runoff
Tougher pollution regulations for livestock operations
Deal better with animal waste
Convert to natural gas, recycle undigested nutrients back into animal feed, extract chemicals from manure to make plastics or cosmetics, biodiesel

72. Laws Can Help Reduce Water Pollution from Point Sources
1972: Clean Water Act, sets the standard
1987 Water Quality Act
EPA: experimenting with a discharge trading policy
Market forces to reduce water pollution, same as air pollution cap & trade
A permit holder can higher levels than allowed in permit if it buys credits from permit holder who polluted below their allotted levels
Could this allow pollutants to build up?
Never lowered

73. Case Study: The U.S. Experience with Reducing Point-Source Pollution (1)
Numerous improvements in water quality
Some lakes and streams are not safe for swimming or fishing
Treated wastewater still produces algal blooms
High levels of Hg, pesticides, and other toxic materials in fish

74. Case Study: The U.S. Experience with Reducing Point-Source Pollution (2)
Leakage of gasoline storage tanks into groundwater
Weaken or strengthen the Clean Water Act

75. Sewage Treatment Reduces Water Pollution (1)
Septic tank system
Wastewater or sewage treatment plants
Primary sewage treatment
Physical process: screens & grit tanks
Secondary sewage treatment
Biological process: aerobic bacteria
Tertiary or advance sewage treatment
Bleaching, chlorination

76. Sewage Treatment Reduces Water Pollution (2)
Should there be separate pipes for sewage and storm runoff?
Health risks of swimming in water with blended sewage wastes

77. Discussion Question 7
Should the EPA rule allowing the U.S. sewage treatment plants to blend partially treated sewage with fully treated sewage and to dump it into waterways anytime it rains or snows be overturned? Explain why or why not.

78. Solutions: Septic Tank System

79. Solutions: Primary and Secondary Sewage Treatment

80. We Can Improve Conventional Sewage Treatment
Peter Montague: environmental scientist
Remove toxic wastes before water goes to the municipal sewage treatment plants
Reduce or eliminate use and waste of toxic chemicals
Use composting toilet systems
Wetland-based sewage treatment systems

81. Dirty Jobs Sewage Treatment

82. Science Focus: Treating Sewage by Working with Nature
John Todd: biologist
Natural water purification system
Sewer water flows into a passive greenhouse
Solar energy and natural processes remove and recycle nutrients
Diversity of organisms used

83. Solutions: Ecological Wastewater Purification by a Living Machine, RI, U.S.

84. Discussion Question 8
What are the disadvantages of using a nature-based system to treat sewage?

85. There Are Sustainable Ways to Reduce and Prevent Water Pollution
Developed countries
Bottom-up political pressure to pass laws
Developing countries
Little to reduce water pollution
China : ambitious plan

86. Solutions: Water Pollution, Methods for Preventing and Reducing Water Pollution

87. What Can You Do? Water Pollution, Ways to Help Reduce Water Pollution

88. Discussion Question 9
What can you do to reduce water pollution? Pick 3 from the chart you feel are the most important, explain why.

89. This powerpoint presentation was taken from: