Water Use, Management, and Pollution Concept Questions

1. What are the three major categories of water use? From what point in the cycle is water generally withdrawn for use? How is it withdrawn and used? (industrial, agricultural, residential; water drawn from surface water and groundwater; withdrawn by pumping and distributed through pipes)

2. How does deforestation impact the water cycle? (water flows faster so less infiltrates; more sediment and less ground water)

3. What is the effect of paving on the water cycle? (less infiltration, more runoff of polluted water)

4. What are the results of overdrawing groundwater? Surface water? Describe the human, ecological, and environmental results of each. (see notes)

5. Describe some problems associated with dam building and diversion projects. (see notes)

6. Experts agree that we need more water. Two ways of getting more water are to increase water supply and to reduce our demand. Compare the potential of each one. (much easier and cheaper to reduce demand; more difficult for individuals though because it requires sacrifice and lifestyle change)

7. How can water demands be reduced in industry, agriculture, and households? (see notes)

8. How does water use by sector differ between rich and poor countries? (developing countries use more water for agriculture and less for industry)

9. What are some ways you can use less water in your personal life? What effect will those actions have long term? (answers will vary)

10. How can we get the general public to recycle and conserve water? (answers will vary)

11. Imagine that you suddenly move to a developing country. What would you miss most about the lack of water? (answers will vary)

12. What are some ways we could encourage people to conserve water? (answers will vary)

13. What are some possible sources of increased water? (sewage, storm water, runoff, gray water, new aquifer or better technology to pump deep water, icebergs, cloud seeding)

14. Describe both phytoplankton and SAV. Where does each get nutrients and light? (phytoplankton are microscopic, SAV macroscopic; phyto get nutrients from water; SAV mostly from substrate)

15. Describe and contrast an oligotrophic and a eutrophic lake. Describe the major producers, nutrient content, turbidity, and dissolved oxygen content of each. (oligotrophic lakes have few nutrients, more DO and are less turbid, eutrophic lakes have lots of nutrients, less DO and are more turbid; oligotrophic lakes have mostly SAV, eutrophic mostly phytoplankton)

16. Why is the natural state of waterways to be oligotrophic? (most nutrients used by land plants so few nutrients reach water; nutrients in water are absorbed by SAV; lack of N and P limit phytoplankton)

17. Describe the causes and results of eutrophication. (see notes)

18. Distinguish between natural and cultural eutrophication. (natural happens slowly; cultural is human-caused and faster)

19. Describe the role played by wetlands in preventing eutrophication. (they slow down water flow, allowing sediments to fall; organisms use the nutrients, cleaning the water)

20. What is BOD? How is it a measure of water quality? (Biological (or biochemical) oxygen demand measures the demand for oxygen in the water; high quality water does not have many organisms (so a low BOD) and is clean)

21. Describe the effect of sediments on waterways and eutrophication. (sediments fill in and close waterways; adds nutrients, increasing eutrophication)

22. Describe some ways by which the results of eutrophication can be addressed. Indicate the costs and benefits of each. (answers will vary)

23. Let’s say a small stream flows near the school grounds at KVHS. Before reaching the school grounds, it flows through a deciduous woods. The class decides to monitor and study the stream’s flow patterns and quality as it flows through the woods and the school grounds. What would you expect to find in the two areas? (as it flowed toward the school, you would expect quality to decrease, diversity of organisms to decrease, litter to increase, BOD to increase)

24. Imagine you own a piece of land with a small, but polluted, lake on it. An engineer offers solutions for various levels of cleanup. As water quality increases, cost increases also. How clean would you want the water to be - fishable, swimmable, drinkable - and how much would you be willing to pay to achieve your goal? You can just make up some numbers to make your point as you think about your priorities and values. (answers will vary)

25. Do you think water pollution is worse now than in the past? On what do you base your opinion? Do you have any personal experience that helps you decide? (answers will vary)

26. Why do we use so much water? Do we need all that we use?