WATER QUALITY

What is quality water?

Is it suitable for a particular use? Ecosystem Drinking Recreation Agriculture

based upon its selected Physical, Chemical, and Biological properties

Ecosystem health Biological: flora and fauna species

Benthos macroinvertebrates Bottom dwellers lacking a backbone, i.e.

Worms, larvae, clams, snails, water striders

Range of Tolerance

Chp 18 .11. When was the Clean Water Act signed into law? 2. What was a goal of the Clean Water Act? 3. List one area of water pollution that has gotten

worse in the past 40 years. 4. Give an example of point source and non-point

source water pollution. 5. List a waterborne disease. 6. What does BOD test for?7. What can lower the DO of a body of water? 8. How can oxygen be added to water? 9. What is the term to describe a body of water that

has low biological productivity? 10. What is cultural eutrophication? 11. Describe an ecological harm caused by cultural

eutrophication.

Oxygen demanding wastes Example: Organic matter Source: sewage, lawn clippings.

Oxygen is required to convert stored energy in organic matter to ATP (cellular respiration).

As O2 dissolves in H2O , energy is releasedO2 + 80% Saturation > 100% saturation + heat.If the system is heated, H2O will not dissolveCool the water , then O2 dissolves.

During the summer, where could the water become anoxic? Why?

A lake becomes stratified in the summer .Prevents mixing of nutrients and oxygen

Why are there large algae blooms in the fall?

Nutrient enrichment Example: N & P Source: Ag. & Urban fertilizers, sewage, manure Eutrophication: Things change. Dead Zones Excess Nitrogen in drinking water:

methemoglobinemia

Infectious agents: Pathogens

Bacteria: Cholera: watery diarrhea that can kill in hours. 3-5 million affected, 100,000 deaths

Virus: Polio: paralyzes muscles, enters through mouth 99% reduction since 1988. Only four

countries are endemic for it. Protist: Giardiasis : severe diarrhea

Coliform testing: Guilt by association

Chemicals: Organic Organic: C-C bonds, C-H bonds Example : Fossil fuels, detergents,

pharmaceuticals DDT: Silent Spring

Miracle chemical: killed lice in WWII Later used to kill mosquitoes

Bio-accumulated in tissues Biomagnified through food chain

Chemicals Inorganic materials Metals: mercury, lead, cadmium

Weathered from rocks into the water. Coal releases mercury into the

atmosphere, which then diffuses on to the water.

Shark, Tilefish, Mackerel, Kingfish, Swordfish

Mercury: causes neurological impairments. Pregnant women should eat 1 can light

tuna/ 3 days Non-metalic: Road salt, arsenic Acids: H2SO4

Other pollutants

Sediments Thermal Radiation

Clean Water Act

1948 30% of Americans had access to municipal sewage treatment that may have only removed chunks

NPDES : 10% of pollution comes from industrial point source

91% rivers, 88% lakes are fishable and swimmable

Navigable waters no longer include some tributaries.

Clean Water Act

Sediments, nutrients & pathogens pose problems

Non-point sources account for 75% of water pollution