1. Water Pollution
Chapter 11-3

2. Water Pollution
Water pollution – the introduction of chemical, physical or biological agents that degrade water quality

3. Water Pollution 2 main causes: Industrialization
Rapid human population growth

4. Developing Countries The only water to drink is often polluted
Spread waterborne diseases

5. Point Source Pollution
Point Source Pollution – pollution discharged from a single source
Factory
Leaking oil tank

6. Nonpoint-Source Pollution
Nonpoint-Source Pollution – comes from many sources
Hard to identify
Boats that leak fuel

7. Wastewater
Wastewater – water that contains waste from home or industry
Wastewater treatment Plant
Filtered enough to return water back to a lake

9. Treating Wastewater
Biodegradable wastes can be broken down by living organisms

10. Sewage Sludge Solid material that remains after treatment Incinerated
Ash buried in landfills
Fertilizers or bricks

11. Artificial Eutrophication
Lakes and streams contain an abundance of nutrients
Human caused
Normally a natural process

12. Artificial Eutrophication
Areas can become swampy
Caused by:
Fertilizer run-off
Laundry soap

13. Algal Blooms Algal blooms – “Floating mats” Can suffocate fish
Algae die and decompose
Dissolved oxygen used in process

14. Thermal Pollution
Thermal Pollution – temperature rise of a body of water
Power plants discharge warm water back into lakes

15. Groundwater Pollution
Enter by pollutants on surface
Percolate into ground water
Oil leaks
Fertilizers
Pesticides
Septic Tank

17. Ocean Pollution 85% of ocean pollution comes from activities on land
Rivers

18. Oil Spills 1989 Exxon Valdez Oil Spill Prince William Sound, Alaska
Each year 37 million gallons spill

19. Oil Spills
2001 Galapagos Islands

21. Biomagnifications Pollution - DDT
DDT – widely used pesticide
Cheap
Active for a long time
Killed variety of insects
Drained into rivers
Can not eliminate from bodies
Non-biodegradable
Not broken down by plants or animals

24. Biological Magnification
Stored in by algae
Herbivores eat algae – concentration raises
Carnivores eat – concentration raises
Affects entire food web

25. Silent Spring 1962 – biologist Rachel Carson
Osprey, Brown Pelican, Bald Eagle
Threatened extinction
Made eggs fragile
1970’s DDT banned

26. Cleaning Up 1969 – Cuyahoga River Cleveland Ohio
Caught fire and burned for days
Clean Water Act of 1972
Goal – To make all surface water clean enough for swimming and fishing by 1983

29. DDT VIDEO CLIP

30. Disaster in the Gulf – Video Clip