1. WATER QUALITY
Measure of substances in water other than water molecules
levels of these substances are set by the Environmental Protection Agency or EPA

2. Potable (drinkable) water is:
Clear
Colorless
Has a neutral pH
Has correct amounts of dissolved oxygen (DO)
Needed for aquatic animals and plants

3. TURBIDITY Cloudiness of water
Caused by: erosion, runoff, algae growth, animals stirring up debri
Leads to:
Increased water temp  less oxygen
Cold water holds more oxygen
Less sun light  less photosynthesis  less oxygen
These can lead to fish kills

4. pH – measure of how acidic or basic water is
Measure on a scale of 0 – 14
Below 7 = acid
Above 7 = basic
7 = neutral --- pure water

5. Over many years these nutrients collect in the water
Waste from organisms and remains of dead organisms contain NITRATES and PHOSPHATES (found in fertilizers)
Over many years these nutrients collect in the water
EUTROPHICATION – build up of nutrients

6. Eutrophication causes more algae to grow – forms a thick green scum on the surface
Blocks out the sun
Decreases the amount dissolved oxygen
Kills aquatic life
Disrupts food webs

7. DISEASE CAUSING ORGANISMS
Detected with a coliform count
Measures E.Coli bacteria
Found in poop
WATER HARDNESS
Measure of the concentration of calcium and magnesium
Hard water does not form suds

8. FRESHWATER POLLUTION

9. What is POLLUTION?
Water Pollution - addition of any substance that has a negative effect on water quality or the living things that depend on water.
Pollutants – anything that causes pollution (chemicals, waste, metals, organisms, petroleum products)

10. Sources of pollution are classified by how they enter the water:
Point Source – specific source of pollution. EX a pipe releasing waste directly into a river.
Non-point Source – source of pollution that cannot be tied to a specific source. EX oil drips from a car. When it rains, the water washes the oil into a nearby creek or pond.

11. POINT SOURCE

12. NON-Point Source

13. EFFECTS OF POLLUTION
Some effects are obvious. It is clear to see the effects of most point sources.
Some non-point sources are not so obvious.
EX -- Pesticides building up in the body of living things. Some pesticides such as move through food chains as organisms at different levels are eaten. The concentration of this chemical increases as you move to the top of the food chain.
This build up can lead to problems like birth defects or cancer.

15. Three major sources of water pollution are human waste, industrial waste and chemical runoff.
The connection that dumping human waste in water can spread disease was only made 150 years ago. Cholera outbreak in 1854 in England. A broken sewage pipe leaked into a common well, spreading the disease and killing hundreds in days.

16. TREATING WATER
1. Filtration – passing water through a screen, gets out the big pieces
2. Coagulation – adding a chemical that produces sticky globs (sink to bottom)
3. Second filtration – passing water through sand or gravel, gets out small stuff (bacteria)
4. Chlorination – adding chlorine kills bacteria. disinfects
5. Additional treatment – flouride may be added

17. Waste water is treated before being pumped being released or
You may have a septic tank in your yard

18. SEPTIC TANK
What is a leach field?

19. INDUSTRIAL WASTE More serious problem often is not treated
Chemicals, smoke and heated water are common pollutants from industries.

20. CHEMICALS
Runoff from Agriculture (fertilizer and pesticides) – lead to Eutrophication
Runoff from roads

21. Smoke and Exhaust
Burning fossil fuels leads to the formation of sulfuric and nitric acids in the atmosphere.
This leads to acid rain. Rain with a pH below 7

26. Bioindicator
Small organisms that are used to monitor the quality of a habitat (aquatic or terrestrial)
These organisms respond to minimal changes in their environment
May indicate unhealthy water

27. POLLUTIONS SOLUTIONS Clean-up and Prevention
Living things filter pollutants out of water
Plant roots absorb stuff
Bacteria eat up toxic chemicals and oil

28. PREVENTION Industries: recycle and reuse water Farmers:
use fewer toxic chemicals
Farmers:
collect runoff water to use for irrigation.
plant fields of grass to filter runoff water.
Dispose of chemicals like paint and oil properly
We need to be good STEWARDS of our water.