1. A World of Water – Water Quality and Management
Unit 5, Topic 6

2. What determines water quality?
Just because you cannot see or smell things in your water does not mean it has nothing in it. Water contains dissolved solids (salts, magnesium, etc.)
If there is a lot of calcium and magnesium in water, we call it HARD WATER
SOFT WATER has less of these

3. How contaminates get into water
Run-off from the land
Soil and rocks
Plants and animals
Human activities

4. Water and People

5. Acid Precipitation

6. pH Scale
Used to describe how much or how little acid is in a solution.

7. Measuring Water Quality

8. Organisms in the Water
Different organisms can live in different kinds of water.
Scientists can use these organisms to determine the quality of water
Midgefly larvae and other
various small worms live in
very polluted water
Caddisfly larvae can only survive
in unpolluted water with lots of
oxygen
Other micro-organisms (bacteria) occur
naturally in water and normally pass through
you without harming you

9. Bioindicator Species
Many plants, birds, fish, turtles, invertebrates (clams, insects) and amphibians (frogs and salamanders) can help us monitor the health of ecosystems
If there is too much pollution in water, the numbers of these bioindicator species may change
They are the best way to detect changes in water quality

11. Monitoring Water Quality
We have set Water Quality Standards for:
Drinking water for people
Protection of organisms living in or near water
Drinking water for livestock
Irrigation of crops
Recreation (especially swimming)

12. Water Management
You will notice that most cities are built near a river or lake. This is done purposefully.
We need to have a reliable water supply therefore city planners and politicians build cities near water supplies.
This is called
water management

13. Water management also involves the wise use of water
We must balance the needs of consumers, industries, agriculture and wildlife

14. Purifying Water
The water we drink must be made potable (safe to drink)
Many communities clean their water through water treatment plants

16. Sustaining Water Resources
Demand for water is increasing as human population rises
Water shortages are forcing countries to develop desalination plants (very costly)

18. You can make a difference

19. Watch “Water Smart – Water as a Natural Resource” Video (15 minutes)