S1C4: Sustainable Management of Water

Question 1

How does variations in precipitation affect availability of water?

Answer 1

The amount of precipitation that an area receives will determine how much water is available

Question 2

Define floods and the 2 types of floods

Answer 2

Floods is an overflow of a large amount of water onto what is dry land
1. Flash Floods
2. River Floods

Question 3

What is a flash flood and where do they occur?

Answer 3

• Exceptionally heavy rainfall over a short period of time
• Occurs in dry areas where there isn’t enough soil or vegetation to allow rainwater to infiltrate the ground
  (Most of the rainwater that falls becomes surface runoff which quickly floods low-lying areas

Question 4

What is a river flood?

Answer 4

Caused by sustained rainfall

OR

Meltwater produced when snow and ice start to melt in spring

These large amounts of rainfall and meltwater enter streams and tributaries, which then flows into the river

Question 5

What is a drought?

Answer 5

Long period of little or no rainfall in a specific area.
(Lasting months or years)

Question 6

What is an ecosystem?

Answer 6

Ecosystem refers to the community of plants and animals found in the rivers that interact with each other

Question 7

How do people use water?

Answer 7

1. Domestic
2. Recreation
3. Agriculture
4. Industry

Question 8

How do people use water domestically?

Answer 8

Used for household activities such as:
1. Bathing
2. Cooking
3. Flushing toilet

Question 9

How do people use water recreation?

Answer 9

For water sports:
1. Canoeing
2. Sailing
3. Sport fishing

Question 10

How do people use water for agriculture?

Answer 10

Growing crops and rearing livestock
(Uses 70% of water in the world)

Question 11

How do people use water for industry?

Answer 11

• Used to cool equipment in factories and power water plants
• Also used to generate electricity when it passes through turbines installed in dams
  (Used about 19% of the water in the world)

Question 12

What is water pollution?

Answer 12

Water pollution occurs when harmful substances enter water bodies and cause water quality to fail

Question 13

What causes water pollution?

Answer 13

• Throwing of rubbish into drains
• Factories releasing toxic waste into the sea to save costs
• No proper systems to treat wastewater
• Leaked landfills due to too much accumulated waste

Question 14

Consequences of water pollution

Answer 14

Pollutants like pesticides and lead kill plants and poison animals that feed on them.

Question 15

How can water be managed sustainably?

Answer 15

1. Improve water quality
2. Reduce water consumption
3. Improving water technologies
4. Importing water

Question 16

How to improve water quality?

Answer 16

Laws are usually implemented to maintain or improve water quality
Eg. Singapore’s Environmental Protection and Management (Trade Effluent) regulations, industries aren’t allowed to release wastewater into water bodies without permission from NEA

Question 17

What is water quality?

Answer 17

Determined by temperature, amount of dissolved oxygen and pH

These factors affect how well aquatic plants are and the range of aquatic animals that can survive

Question 18

Benefits of improving water quality

Answer 18

• Greater control of water quality can ensure aquatic plants grow well and the range of aquatic animals to survive.
• It can help to change people’s mind sets and increase awareness and appreciation of our water

Question 19

Challenges of improving water quality

Answer 19

• Hiring manpower to monitor the water quality and to check on industries to release wastewater can be time consuming
• Hiring more manpower can be expensive

Question 20

How to reduce water consumption?

Answer 20

Singapore has been encouraging its people to conserve water
Eg. Water Efficiency Labelling Scheme (WELS) by PUB grades water appliances with a tick rating so that people are aware of more water-efficient products in the market
Although water is a renewable resource, it needs to be treated and cleaned, and it can run out if it is used up faster than it can be replenished

Question 21

Benefits of reducing water consumption

Answer 21

• Teaches many people about importance of water in their lives
• Can make long-lasting positive changes in people’s use of water

Question 22

Challenges of reducing water consumption

Answer 22

• It will take time to change people’s behaviour
• The success of public education depends on whether people want to change their behaviour. Some people may not respond positively

Question 23

What are the 2 water technologies used in Singapore?

Answer 23

NEWater and desalinated water

Question 24

What is NEWater

Answer 24

NEWater is recycled water which can be used more than once.

Question 25

What is desalinated water?

Answer 25

• Turning seawater into drinking water using advanced membrane technology
• Seawater cannot be used directly due to its high salt content

Question 26

Benefits of improving water technologies

Answer 26

• Does not rely on rainfall and can be used to supplem ent water supply during a long dry spell
• Singapore is an island and surrounded by a lot of seawater, which can be used for desalination

Question 27

Challenges of improving water technologies

Answer 27

• Very expensive as production is energy intensive
• Large amounts of chemicals and salt solutions are produced during the desalination process. If these are not disposed of properly, it may result in pollution

Question 28

How do countries import water?

Answer 28

Water scarce countries may import water from countries which has relatively abundant water resource

Question 29

Benefits of importing water

Answer 29

• Does not require land, so land is freed up for other uses
• Cheaper source of water compared to NEWater or desalinated water

Question 30

Challenges of importing water

Answer 30

• May not be enough to meet water demands
• Water agreements will expire and there are no guarantee of future agreements