Chapter 18: Water Pollution Flashcards
How many years ago was Lake Erie on the brink of collapse?
40 years
When did President Nixon sign the Clean Water Act?
In 1972
Clean Water Act
This Act has been called the nation’s most popular environmental legislation. Goal of the act: all of the nation’s water should be fishable and swimmable
What percent of Americans believe we should invest in clean water?
90%
What are the 3 most common sources of pollution today?
- Erosion from farm fields and construction sites
- Agricultural runoff
- Airborne mercury and sulfur
Pollution
Is actually any physical, biological or chemical change that adversely affects living organisms or makes water/air unsuitable for use
Point Sources
Discharge pollutants from specific locations
Examples: Factories, power plants, sewage
plants, oil wells, underground coal mines, etc.
These facilities have pipes, ditches, etc.
Nonpoint Sources
Have no specific location of discharge
Examples: Runoff (from fields, feedlots, golf
courses, logging areas, construction sites,
parking lots, etc), atmospheric deposition
(contaminants carried in air are precipitated
into watersheds and surface waters).
What 2 groups are water pollution divided into?
Pollutants causing health problems and pollutants causing ecosystem disruption
Pollutants causing health problems
Infectious agents, inorganic chemicals, organic chemicals and radioactive materials
Pollutants causing ecosystem disruption
Sediment, thermal, plant nutrients
Pathogenic organisms cause what?
Diseases
The most important water born pathogens cause what diseases?
Typhoid Cholera Bacterial and amoebic dysentery Enteritis Polio Infectious hepatitis Shistosomiasis
What 3 diseases are caused by aquatic insect larvae?
Malaria, yellow fever, filariasis
What fraction of children under 5 die of water born diseases?
2/3
How is drinking water disinfected?
Chlorination process
Coliform Bacteria
Any bacteria that lives in the colon or intestines of humans or animals.
What are some examples of coliform bacteria?
Eschericha coli (E.coli), Shigella, Salmonella, and Lysteri
When is water not swimmable?
If colony count exceeds 200 per 100 ml of water
How many parts per million of oxygen is required for aquatic life to survive?
6 ppm
How many parts per million of oxygen do fish like?
8 ppm
How many parts per million only support worms and other decomposers?
2 ppm
Organic waste and fertilizers are rich in what two elements?
Nitrogen and phosphorus
What does BOD stand for?
Biochemical Oxygen Demand
BOD tests incubate water for how many days?
5 days
What does DO stand for?
Dissolved Oxygen
Oxygen Sag
Term for oxygen levels decreasing downstream