This blog was done by :
-Gilliah
-See Yan
-Nathan Patrick
-Adriel
-Jaren
Of Class 2/5.
Thank you for reading our blog. ^^
Wednesday, April 10, 2013
"Evaluate which method you think is the best and provide reasons for your choice."
As Singapore is a small country with little land area,
building water catchments is not a very effective way due to land scarcity and
rising demand for land. However it is the cheapest way among all the taps to
obtain water for the country as rainwater is easier to purify, it is also able
to collect more water during high or low rainfall, thus increasing the water
available in Singapore. At the same time, more nature reserves and areas of
greenery can be conserved too. But if Singapore were to fall into a period of
drought one day, the water catchment areas would be useless in providing water
for the citizens of the country.
Another way that Singapore obtains water is by importing
water. This is the most convenient way but least reliable to obtain water as
Malaysia is located close to Singapore. However, importing water is a risky way
to obtain water, and it is not a self- sufficient and long run method. It is
not self-sufficient and risky as it is not possible for Singapore to keep
relying on imported water as there is always an underlying threat that Malaysia
will cut off their water supplies with us. It is not a long run method to
obtain water as international agreements for water will expire. It may also be
very expensive if the country selling us water decides to raise the price to
earn more money.
Desalination is also another effective way to increase
Singapore water’s supply. It is a reliable source of water, sustainable in the
long-run and is a diversified water supply system. However, it is the most expensive among the 4
taps. It also requires large amounts of energy. For example, SingSpring’s
desalination plant in Tuas, Singapore cost $200 million.
Lastly,NEWater is also another effective way to increase
Singapore water’s supply as wastewater is made potable for people through
technology and thus reduce Singapore’s dependence on other countries for
countries. It is also able to conserve and recycle used water. Among the 4
taps, it is the most reliable tap. This will enable Singapore to be more
self-sufficient and is sustainable in the long-run. However, the process to
treat the water is very expensive and requires large amounts of energy. For
example, Bedok’s NEWater plant cost $6.82 million. Due to the removal of
nutrients in the water, people may not get used to the taste of the water.
In conclusion, we think that NEWater is the most effective
way of increasing Singapore’ water supply as Singapore is a problem of water
shortage if the source of water is unreliable. It will cause negative impacts
such as dehydration and insufficient water for industries and crops. Thus, it
is important for Singapore to have a reliable source of source that would allow
us to be self-sufficient in the long-run. Reliability is the most important
among all. Also, NEWater allows used water to be recycled and conserved. Although it is expensive and have a different
taste, Singaporeans can still get used to the taste and afford it.
Singapore’s 4th
National Tap: Desalinated water
Seawater that is found
in Singapore’s seas is desalinated in the desalination plant.
There is a desalination plant is Tuas. Seawater is desalinated by removing
unwanted waste in the water through the process if reversed osmosis. This
ensures that dirty particles are filtered out and that the water is clean. But
in this process, some of the minerals in the water are also removed thus the
water tastes funny, so, after removing the unwanted waste in the water they re-mineralized
the water.
Desalinating water is
an expensive method to obtain water for the country. The cost of building and
operating the desalination plant is very expensive. The new SingSpring
Desalination Plant cost$200 million to build. But it is a diversified and
sustainable supply of water for Singapore.
CREDITS: google for images and Singapore PUB website
CREDITS: google for images and Singapore PUB website
1
NEWater-
The 3rd National Tap:
What is
NEWater?
NEWater is reclaimed
water produced by Singapore's Public Utilities Board (PUB). It is used water
that is treated to become potable water. The water is clean and suitable for
drinking purposes, but is mostly used for industrial operations. It is the 3rd national tap of
Singapore’s water supply system and is a practice that had been ongoing for
decades in Singapore. Currently, there are a total of 4 operational NEWater factories
in Singapore, at Bedok, Kranji, Ulu Pandan and Changi.
Process:
NEWater is reclaimed
water made by purifying used water through a three-stage process. During the
treatment process, used water goes through the 1st stage- microfiltration.
At this stage, unwanted substances are removed,
being filtered out by membranes.
It then
reaches the second stage- reverse osmosis. At this stage, the water passes
through into a semi-permeable membrane which only allows water molecules to
pass through. This ensures that unwanted substances such as bacteria and heavy
metals are removed. In the end, high-grade and clean water is obtained.
As an extra
precautionary measure, the water next undergoes the 3rd stage- Ultraviolet
disinfection to ensure the purity of the product water. Alkaline chemicals are
added to the water to restore its PH balance. Finally, the water becomes ultra-clean
and safe for drinking.
Advantages:
1) It is
sustainable in the long run and is known as the “pillar of Singapore’s water
sustainability”.
2) We will
always have a ready source of water.
3) It is a self-dependent method as it reduces Singapore's reliability
on imported water from other countries.
4) It reduces wastage of water as used water is
recycled. Thus, NEWater helps to maximize the use of water on Earth.
Disadvantages:
1) People are not used to drinking NEWater
as the taste is different due to the removal of nutrients during the process.
2) It is costly. Bedok’s NEWater plant
cost $6.82 million.
Imported water-
The 2nd national tap
What are international agreements?
An international agreement is an agreement between countries regarding the
supply and the use of resources over a specific time.
Imported water:
Singapore and Malaysia had signed two water agreements- the first one
was signed in 1961 and expired in 2011 and the second one was signed in 1962
and is going to expire in 2061. Singapore had been importing water from
Malaysia since 1920. Singapore buys raw water from the state of Johor and Johor
buys back the water after it has undergone through treatment and turned into
potable water.
Process:
Singapore receives
water from Malaysia through three large pipelines that are built parallel to a
two-km causeway which connects the two countries.
Advantages:
11) It is a convenient way of obtaining
water supplies
Disadvantages:
1) It is not sustainable in the long
run as supply of water will be affected if Malaysia decides not to extend the
contract when it expires
2) It might be very costly as countries
might want to increase the price of their water to earn money.
3) It is not a self-dependent solution
as Singapore is relying on Malaysia for water.
Singapore’s First
National Tap: Is the water catchment areas in Singapore
As
Singapore is a small island, they do not have aquifers and lakes, thus they
need to maximise whatever water they can harvest. And this includes the
rainwater. Water catchment areas are areas by which rainfall is collected and purified
for various uses. In Singapore, we currently have 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 channelled 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
Water catchment
areas are usually located near coastlines, for example in Bedok or MacRitchie.
Water collected in the water catchment areas are usually cheaper to purify as
compared to used water. It increases the amount of water collected thus
provides a ready source of usable water for the country to use. This allows
Singapore to be self- sufficient. However, it is not very viable to Singapore
as there is land scarcity and building water catchment areas require a lot of
land, and this results in competition for land and there will not be enough
land for other purposes.
Despite the
water scarcity in Singapore, Singapore had taken many actions to deal with their
water constraints to support its growing population and prospering economy. Currently,
Singapore has 4 national taps to deal with its water constraints and they are:
1) Local catchment areas
2) Imported water
3) NEWater
4) Desalinated water
Subscribe to:
Posts (Atom)