1. Water Pollution Reference: G. Tyler Miller’s Living in the Environment 14 th Edition Prepared by Shohail Motahir Choudhury

5. Sources of Water Pollution Point sources Nonpoint sources Water quality

6. Point and Nonpoint Sources NONPOINT SOURCES Urban streets Suburban development Wastewater treatment plant Rural homes Cropland Factory Animal feedlot POINT SOURCES

10. Oxygen Sag Curve

12. Pollution of Lakes

13. The Great Lakes Fig. 22-8 p. 500

16. Ocean Pollution Fig. 22-11 p. 504

18. Oil Spills Sources: offshore wells, tankers, pipelines and storage tanks Effects: death of organisms, loss of animal insulation and buoyancy, smothering Significant economic impacts Mechanical cleanup methods: skimmers and blotters Chemical cleanup methods: coagulants and dispersing agents

19. Solutions: Preventing and Reducing Surface Water Pollution Nonpoint Sources Point Sources Reduce runoff Buffer zone vegetation Reduce soil erosion Clean Water Act Water Quality Act

20. Technological Approach: Septic Systems Require suitable soils and maintenance

21. Technological Approach: Advanced (Tertiary) Sewage Treatment Uses physical and chemical processes Removes nitrate and phosphate Expensive Not widely used

22. Drinking Water Quality Safe Drinking Water Act Maximum contaminant levels (MCLs) Purification of urban drinking water Bottled water Protection from terrorism Purification of rural drinking water

23. Sustaining Biodiversity