water our valuable resource

Textbook page 114 - 125

Living things need water for survival and well-being – almost 70% of the human body consists of water Water bodies are habitats for plants, animals and marine creatures Water bodies are sources of food (seafood) for humans Water is needed for many human activities such as washing and cooking

Fresh water on Earth

97% - salt water

2% - frozen fresh water 1% - fresh water

Unevenly distributed

HYDROLOGICAL HYDROLOGICAL CYCLECYCLE

SURFACE RUNOFF

GROUND WATER

CONDENSATION

EVAPORATION & TRANSPIRATION

PRECIPITATION

Population growth - Increase in water usage for farming, industry and domestic use Rising living standards - Increase in water usage for creating comfortable and convenient modern lifestyles Pollution – chemical waste from factories, farms and households Uneven distribution of water – lack of natural water sources or water is polluted

1. Increasing the price of water- Reduces water wastage and promotes water conservation- Affects those who cannot afford to pay the higher price of water, the poor will suffer

2. Increasing the size of catchment areas- Keeps the cost of water treatment down and rainwater is cleaner and does not contain salt- Forests are conserved and helps to slow down global warming- Less land available for other purposes such as housing, roads, industries- Catchment areas will not be useful during seasons of low rainfall or drought

3. Using technological advances- Recycling waste water, desalination and using pumps to extract groundwater- Costly, require a large amount of energy and only developed countries can afford- Recycled and desalinated water taste differently – many people are not used to it

4. Conserving water through public education -Driving home the message that fresh water is limited and precious, and must be carefully used at all times through schools and campaigns- Government does not need to invest on water-related facilities and money can be used to improve infrastructure such as roads- Needs cooperation from everyone but many people do not see the importance of it

5. Establishing international agreements - An arrangement between two or more countries regarding the supplying and use of water over a specific period of time- Enforcing water agreements can be difficult as there are often political issues tied to these agreements

Limited water and can only supply half of what we need Water shortage - due to no large river to provide freshwater and inadequate rainfall Increasing demand of water due to growing population, providing better standard of living and developing high-tech industries

Water scarcity makes us very vulnerable, long term water shortage will have a big impact on the whole nation Machines in factories get overheated and cannot function – factories close down and jobs are lost Restaurants and hotels cannot run businesses - tourist industry gets affected and revenue will drop Lack of water for domestic use – standard of living drops and people might leave the country

Water from local catchment areas Imported water - buying water from Malaysia (Expiry date of water agreements – 2011 and 2061) Recycled water – removing impurities from used water Desalinated water – removing salt from sea water

Local catchment area

Imported water Recycled water

Desalinated water

Singapore’s Water Supply

1. Reservoir

2. Pumping Station

3. Raw water mixing chamber

4. Settling tank

5. Sand filters

6. Clear water tank 7. Pumping Station

8. Servicereservoir

Water conservation taxes – additional fee added to the price of the water consumed by households and varies according to the amount of water they use

Save water campaigns to encourage people to conserve water – talks conducted in schools, leaflets distributed to households, mobile exhibitions on the use of water-saving devices and water conservation tips

Water rationing exercises – supply of water is temporarily cut off to spread awareness on the importance of conserving water