Singapore's four national taps :
✡ Imported Water
✡ Local Catchements
✡ NEWater
✡ Desalinated Water
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TAP 1:
IMPORTED WATER
Singapore has been importing water from Johor, Malaysia, under two bilateral agreements.
The first agreement expired in August 2011 and second agreement will expire in 2061.
It may be one of the most developed nations in Southeast Asia, but on the densely packed urban island of Singapore, a simple glass of water doesn't come cheap, or easy.
A highly modernized city-state with a population of around 5 million, Singapore has no native freshwater supplies. Instead, it relies heavily on imports from neighboring Malaysia -- which delivers up to 250 million gallons a day -- to satisfy the nations huge and growing thirst.
At present, imports account for around 40% of its total water supply but, according to Singapore's Public Utilities Board (PUB), an array of alternative sources are in place to significantly reduce the country's future dependence on foreign supplies.
The pipe that carries imported water from Johor Bahru to Singapore
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TAP 2:
LOCAL CATCHMENTS
Currently, Singapore uses two separate systems to collect rainwater and used water. Rainwater is collected through a comprehensive network of drains, canals, rivers, and storm water collection ponds before it is channeled to Singapore’s 17 reservoirs for storage. This makes Singapore one of the few countries in the world to harvest urban storm water on a large scale for its water supply. By 2011, the water catchment area has increased from half to two-thirds of Singapore’s land surface with the completion of the Marina, Punggol and Serangoon reservoirs. With all the major estuaries already dammed to create reservoirs, PUB aims to harness water from the remaining streams and rivulets near the shoreline using technology that can treat water of varying salinity. This will boost Singapore’s water catchment area to 90% by 2060. The picture below shows a map of Singapore’s reservoirs.
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TAP 3:
NEWATER
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| the NEWater plant |
NEWater is produced from treated used water that is further purified using advanced membrane technologies and ultra-violet disinfection, making it ultra-clean and safe to drink. NEWater has passed more than 65,000 scientific tests and surpasses World Health Organisation requirements, a testimony of its high quality and reliability. Currently, NEWater meets 30% of the nation’s water needs. By 2060, Singapore plan to triple the current NEWater capacity so that NEWater can meet 50% of their future water demand.
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TAP 3:
DESALINATED WATER
the desalination plant in Singapore
Desalinated water is produced by desalination. Desalination refers to any of several processes that remove some amount of salt and other minerals from saline water. More generally, desalination may also refer to the removal of salts and minerals, as in soil desalination.
In September 2005, Singapore turned on its fourth National Tap, with the opening of the SingSpring Desalination Plant in Tuas. The SingSpring desalination plant was PUB’s first public-private partnership (PPP) project. This plant can produce 30 million gallons of water a day (136, 000 cubic meters) and is one of the region’s largest seawater reverse-osmosis plants. At the SingSpring plant, sea water goes through a pre-treatment process where suspended particles are removed. In the second stage, the water undergoes reverse osmosis (RO). This is the same technology used in the production of NEWater. The water produced is very pure and is re-mineralised in the third stage. After treatment, desalinated water is blended with treated water before it is supplied to homes and industries in the western part of Singapore.
desalination process
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Evaluate which method you think is the best and provide reasons for your choice
For local catchment water, advantages are that increasing catchment areas will not only help to increase the amount of rainwater collected in a country, but also help to keep the cost of water treatment down. This is because rainwater is much cleaner than used water and does not contain salt unlike sea water. Hence, it is easier and less costly to purify. Also, when more land in a country is set aside to build water catchment areas, more forests are conserved in the process. People will thus be able to enjoy a wider range of nature and recreational areas. However, the disadvantages are that setting aside more land for this purpose means that there will be less land available for other purposes such as the building of houses, industries and roads. This is a problem for countries struggling with land constraint like Singapore, where half of the land area is already set aside as water catchment areas. Furthermore, rain is a natural event and a country has little control over the amount of rainfall. Therefore, in times of drought or little rainfall, the land used for these catchment areas will be ineffective.
For imported water, the advantage is that it’s a convenient way of obtaining water. However, the disadvantage is that international agreements do not last forever. When these agreements expire, countries will have to renegotiate the terms for a new agreement. These countries cannot be certain that they will always have enough water to meet their needs.
For NEWater and desalinated water, the advantage is that the sources of water are unlimited. However, it is very costly and requires large amounts of energy. Also, people may not get used to the idea of drinking it as the minerals in the water are removed during the treatment process, giving it a different taste from water obtained from reservoirs.
In my opinion, desalinated water and NEWater are the best methods. Even though both are very costly and require large amounts of energy, they are the most reliable. Since the European country is rich, it can afford the costs. Therefore, desalinated water and NEWater are the best choices to prevent water constraint.
Sources:
Earth, our home Secondary 2 Textbook
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