17 TH MILLER/SPOOLMAN LIVING IN THE ENVIRONMENT Chapter 20 Water Pollution

The Seattle, Washington Area, U.S. Fig. 20-1, p. 528

Core Case Study: Lake Washington 1950s: Sewage treatment plants were dumping treated _______________ into Lake Washington 1955: Dr. W.T. Edmondson of the University of Washington discovered ___________________ in the lake Commonly called ________________ algae Grew quickly while fish populations _____________ Chief nutrient feeding the algae was ______________ wastewater cyanobacteria blue-green declined phosphorus

Core Case Study: Lake Washington Edmondson and his team wrote educational letters to the plant ___________________ as well as the ______________ Public pressure on elected officials led to cleanup of the lake Sewage treatment plant effluents redirected to Puget Sound…where tides would __________ and ___________ them with ocean water Facing new pollution challenges with the _________ population in the area managers public mix dilute growing

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.

Water Pollution Comes from Point and Nonpoint Sources (1) Water pollution Change in water quality that can __________ organisms or make water ___________ for human uses Usually involves… Contamination with chemicals Excessive heat ( _____________ pollution) Point sources Located at _________________ places Easy to identify, monitor, and regulate Not often regulated in ________ though Drainage pipe harm unfit thermal specific LDCs

Water Pollution Comes from Point and Nonpoint Sources (2) Nonpoint sources ____________ and diffuse areas, rather than points, from which pollutants enter bodies of water or air Difficult to identify and control Expensive to clean up Sediment pollution As measured by weight, the _______________ source of water pollution Broad largest

Water Pollution Comes from Point and Nonpoint Sources (3) Leading causes of water pollution 1.________________________ activities Sediment eroded from the lands Fertilizers and pesticides Bacteria from livestock and food processing wastes 2.___________________ facilities Example: Coal ______ is often stored on land or in slurry ponds that can ___________ and contaminate nearby bodies of water Coal Ash Truck Agricultural Industrial ash leak

Water Pollution Comes from Point and Nonpoint Sources (3) 3. _________________ Disturbs the land, causes __________________ and often involves the use of ______________ chemicals Mining Waste Mining erosion toxic

Plastic Wastes in Mountain Lake Fig. 20-6, p. 531

Major Water Pollutants Have Harmful Effects One of the major water pollution problems we face is exposure to _____________ ______________ organisms through water contaminated with human and animal waste The World Health Organization (WHO) More than 1.6 million people die _________________ from waterborne infectious diseases, mostly under the age of _____ infectiousdisease every year 5

Common Diseases Transmitted to Humans through Contaminated Drinking Water Table 20-2, p. 532

Major Water Pollutants and Their Sources Table 20-1, p. 532

Science Focus: Testing Water for Pollutants (1) Scientists use a variety of tests to determine water quality Escherichia coli, _____________ testing A sample of drinking water should contain ________ colonies of E. coli A sample of swimming water should contain no more than ________ colonies of E. coli Raw sewage contains several million colonies Level of dissolved oxygen (_____) E. coli no 200 DO

Water Quality as Measured by Dissolved Oxygen Content in Parts per Million Fig. 20-A, p. 533

Science Focus: Testing Water for Pollutants (2) Chemical analysis Indicator species __________________ can be removed to determine what pollutants are in their tissues _________________ feed by filtering water through their bodies Genetic engineering: developing bacteria and yeast that ___________ in the presence of a particular toxic chemical Color and turbidity of the water Cattails Mussels glow

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

Streams Can Cleanse Themselves If We Do Not Overload Them Streams can cleanse themselves of degradable wastes through… _____________________ Bacterial _________________ of wastes This process does not work when… Pollutants _________________ the system Stream flow is _______________ (damming, drought, etc.) Also cannot remove nondegradable waste Oxygen sag curve Dilution decomposition overload reduced

Dilution and Decay of Degradable, Oxygen- Demanding Wastes in a Stream When bacteria break down biodegradable waste, DO levels __________, creating an oxygen _________ curve This reduces or eliminates populations of organisms with ____________ oxygen requirements until the stream is cleansed of oxygen-demanding wastes. Also caused by ______________ water drop sag high heating

Fig. 20-7, p. 534 Point source Pollution- tolerant fishes (carp, gar) Fish absent, fungi, sludge worms, bacteria (anaerobic) Types of organisms Normal clean water organisms (Trout, perch, bass, may fl y, stone fl y) Pollution- tolerant fishes (carp, gar) 8 ppm Normal clean water organisms (Trout, perch, bass, may fl y, stone fl y) Dissolved oxygen (ppm) 8 ppm Biochemical oxygen demand Recovery Zone Clean Zone Septic Zone Decomposition Zone Clean Zone

Stream Pollution in More Developed Countries Laws enacted in the _________ to control water pollution have greatly increased the number of waste water _____________________ in the U.S. and other ________ Successful water clean-up stories Ohio Cuyahoga River, U.S. – was once ____________ Thames River, Great Britain – was basically considered a smelly ______________ in the past Water contamination still sometimes occurs though due to the __________________ or _____________ release of chemicals 1970s treatment plantsMDCs flammable sewer accidentaldeliberate

Stream Pollution in More Developed Countries Cuyahoga River, Ohio Thames River, Great Britain

Global Outlook: Stream Pollution in Developing Countries __________ of the world’s 500 major rivers are polluted – most run through _______ A majority of these countries… cannot ____________ to build waste treatment plants Do not have or do not enforce law for controlling water pollution Most cities in LDCs discharge _______ of their untreated sewage directly into rivers Half LDCs afford 80-90%

Natural Capital Degradation: Highly Polluted River in China Fig. 20-8, p. 535 This river has turned greenish-black due to uncontrolled pollution from thousands of ______________ Modernization of Chinese cities is forcing industries to move to ____________ areas exposing people in the countryside to polluted water – high ________ rates factories rural cancer

Trash Truck Disposing of Garbage into a River in Peru Fig. 20-9, p. 536

Review Questions Fig. 20-9, p. 536 What are the three leading causes of water pollution? How does oxygen demanding waste affect a river? Agriculture Industry Mining Reduces oxygen – oxygen sag curve Eliminates high oxygen species until pollutants are removed

Review Questions Fig. 20-9, p. 536 Under what conditions can rivers cleanse themselves? System not overloaded Water flow not reduced Pollutants are degradable