1. Water Pollution
Chapter 11

2. Water Pollution
Water pollution is the introduction of waste matter or chemicals that are harmful to organisms living in the water or to those that drink or are exposed to the water.
The two underlying causes of water pollution
industrialization
rapid human population growth

3. Water Pollution
In developing parts of the world, water pollution is a big problem
drinking water is polluted with sewage and agriculture runoff, which can spread waterborne diseases.
Water pollution comes from two sources:
point sources
nonpoint sources.

4. Point-Source Pollution
Point-source pollution is pollution that comes from a specific site.
Leaking oil tanker
Factory
Wastewater treatment plant
Enforcing cleanup is sometimes difficult.

5. Nonpoint-Source Pollution
Non-point source pollution is pollution that comes from many sources rather than from a single specific site.
Pollution that reaches a body of water from streets and sewers.
People spraying pesticides on their lawns

6. Point and Nonpoint Sources of Pollution

7. Principal Water Pollutants
Wastewater
Artificial Eutrophication
Thermal Pollution
Groundwater Pollution
Ocean Pollution

8. Wastewater
Wastewater is water that contains wastes from homes or industry through a series of sewage pipes to a wastewater treatment plant.
At a wastewater treatment plant, water is filtered and treated to make the water clean.

9. Treating Wastewater
Most of the wastewater from homes contains biodegradable material that can be broken down by living organisms.
Animal and plant wastes
Paper
Soap
One of the products of wastewater treatment is sewage sludge

10. Wastewater Treatment Process

11. Artificial Eutrophication
Most nutrients in water come from organic matter,
leaves and animal waste
This is broken down by decomposers such as bacteria and fungi.
When lakes and slow-moving streams contain an abundance (a lot) of nutrients, they are eutrophic.

12. Artificial Eutrophication
It’s a natural process
For example, a body of water becomes a swamp or marsh.
Accelerated when inorganic plant nutrients enter the water
Phosphorus (algae growth) and nitrogen
waste disposal and land drainage
The major causes are
fertilizer
phosphates in some laundry detergents.

14. Thermal Pollution
Thermal pollution is a temperature increase in a body of water that is caused by human activity
Thermal pollution can occur when power plants and other industries use water in their cooling systems

15. Thermal Pollution Thermal pollution can cause large fish kills
If the temp of a body of water rises even a few degrees, oxygen levels the water can hold decreases.
aquatic organisms may suffocate and die.

16. Groundwater Pollution
Pollutants usually enter groundwater when polluted surface water infiltrates down.
Any pollution at the surface can affect it.
Pesticides
herbicides
chemical fertilizer
petroleum products
septic tanks

17. Groundwater Pollution

18. Ocean Pollution
Ships can legally dump wastewater and garbage overboard in some parts of the ocean.
But at least 85 percent of ocean pollution, includes pollutants from land or the coast line.
oil
toxic wastes
medical wastes
Sensitive coastal ecosystems, such as coral reefs, are the most effected by pollution.

20. Oil Spills Ocean water is also polluted by accidental oil spills.
Each year, about 37 million gallons of oil from tanker accidents are spilled.
only account for about 5 percent of oil pollution (cities and towns, nonpoint)

21. Oil Spills

23. Water Pollution and Ecosystems
Although there are very apparent problems associated with water pollution, many of the effects of water pollution can be even more far reaching.
Pollutants accumulate in the environment
This threatens the entire ecosystem

24. Biomagnification
Many tiny organisms eaten by larger organisms in a food chain/web can cause the effects of water pollution to impact the top of the food chain much more harshly
Ex: Mercury in fish

25. Cleaning Up Water Pollution – U.S.A.
1972 Clean Water Act (CWA)
1972 Marine Protection, Research, and Sanctuaries Act, amended 1988
1975 Safe Drinking Water Act (SDWA), amended 1996
1980 Comprehensive Environmental Response Compensation and Liability Acti (CERCLA)
1987 Water Quality Act
1990 Oil Pollution Act

26. 1972 Clean Water Act
National goal: make all surface water safe to fish/swim by 1983
Banned pollutant discharge into surface water after 1985
Required metals be removed from wastewater

27. 1972 Marine Protection, Research, and Sanctuaries Act, amended 1988
Allowed the EPA to control the dumping of sewage wastes and toxic chemicals in U.S. waters

28. 1975 Safe Drinking Water Act, amended 1996
Programs to protect groundwater/surface water from pollution
Empowered communities in the protection of source water
Strengthened public right-to-know laws
Provided water system infrastructure assistance

29. 1980 Comprehensive Environmental Response Compensation and Liability Act
A.K.A. Superfund Act
Makes owners, operators, and customers of hazardous waste sites responsible for the cleanup of the sites
Reduced pollution of groundwater by toxic substances leached from hazardous waste dumps

30. 1987 Water Quality Act
Supports state and local efforts to clean polluted runoff
Established loan funds to pay for new wastewater treatment plants
Created programs to protect major estuaries

31. 1990 Oil Pollution Act
Attempts to protect U.S. waterways from oil pollution by requiring that oil tankers in U.S. waters be double-hulled by 2015