What are the disadvantages of the 4 National Taps?

Answer 1

1) Disadvantages of Local Catchment

The local catchment, meaning reservoirs, are dependent on the rainfall in Singapore. As the annual rainfall fluctuates, so does the amount of water collected in our 17 reservoirs around Singapore. If we experience a drought, this National Tap will be heavily affected. As it accounts for 50% of Singapore's total water needs, this may be a serious problem if a hiccup in local catchment occurs. Yearly, we experience dry spells throughout the June-August period of time, affecting our water supply during these months. The reservoirs also take up a huge amount of valuable space in Singapore. They occupy 2/3 of Singapore's limited land space of 704km^2. Singapore is currently the 2nd most densely populated country in the world, right behind Monaco. We have 5.312 million people, so land is scarce. Thus precious land space used up for local catchment is a big problem in Singapore.

2)Imported Water

We have made 2 agreements with Malaysia over the importing of water. The first one, established in 1961, expired in 2011, while the 2nd one signed in 1962 ends in 2061. In turn, Malaysia is allowed the right to buy back some of the potable water back from Singapore after we have treated it. Singapore hopes to become fully self-sufficient in water when 2061 comes. The problem with importing water from Malaysia is that we are too dependent on Another Country. If a war breaks loose, or tensions become so intense that Malaysia decides to stop the water supply to Singapore, this would be disastrous. This accounts for 1/3 of Singapore's water needs, and this is no small amount. The instability of such an agreement is the disadvantage of importing water from overseas.

3)NEWater.

NEWater treats sewer water through several advanced membrane systems and UV disinfection. This leads to Singaporeans harbouring a stereotype against NEWater, thinking of it as waste water. This discourages people from buying and drinking the treated water, even as NEWater has exceeded the guidelines from international water standards. NEWater's equipment also requires a large amount of investment for research beforehand, after that also maintaining the filters and membranes as well as the electricity cost of the water treatment costs a bomb, affecting Singapore's economy. Although NEWater takes up a small percentage of Singapore's water demands, every percent counts in the resource-scarce Singapore, and if the people are not willing to accept NEWater the water supply will continue to dwindle.

4) Desalination

Desalination is the process of extracting clean, potable water from impurities in seawater. This means the water has to go through several filters and Reverse Osmosis and other water technological advances to clean the water and remove the salt. This results in a huge cost in producing drinkable water through desalination. The high economic cost is the major reason why we only have 1 desalination plant in Tuas now, the SingSpring Plant. It meets 10% of Singapore's needs currently, and Singapore is building another desalination plant. 70 million gallons of water is expected to be produced by the second plant upon completion in 2013.

Hope I helped a little.