Climate Sense

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daptation

and

itigation

trategies

results in another drop at a multiplier of two. At higher

recycling rates, a higher multiplier effect could be

achieved. Instead of building all new capacity through

catchment expansion or costly desalination, 50 per cent

of it can be made up through recycling.

Both desalination and NEWater have important roles

to play to mitigate climate change. Both also have the

advantage of being independent of rainfall fluctuations,

thus increasing resilience against variation. Together, they

have put Singapore in a strong position to meet long-term

sustainability and the uncertainties of climate change.

Conserve, Value, Enjoy

Reducing demand is another key strategy. PUB recog-

nizes that simply encouraging the public to conserve

water is not enough – a holistic approach is required.

PUB has a network management plan to ensure

that leaks are minimized, thus reducing unaccounted

for water. The use of good quality pipes and fittings,

efficient management, active leakage controls, manda-

tory and accurate metering and strict legislation on

illegal draw-offs has reduced losses from 10 per cent

in the early 1990s to less than 5 per cent today. The

network has less than seven leaks per 100 kilometres

annually, a vast improvement from the 1980s, when

there were more than 100 per 100 kilometres. This has

been achieved by using good pipe materials, system-

atically replacing old pipelines and the active detection

of underground leaks. By reducing losses and keeping

them in check, there is less pressure to expand sources.

PUB has also addressed the issue of water pricing. A

Water Conservation Tax (WCT) is imposed on every

drop of potable water supplied. This is applicable to

all users, both domestic and non-domestic. The WCT

in 2008, is located right in the heart of the central business district. It

collects runoffs from the largest, most urbanized catchment (10,000

hectares), and increases water catchments to two-thirds of land area.

Singapore imports water from Malaysia through the 1961 and

1962 Water Agreements, until 2011 and 2061 respectively. Water

from local catchments and that imported under these agreements

is sufficient to meet Singapore’s needs. It has, nevertheless, supple-

mented them with NEWater and desalination, ensuring there will be

no need to renew the 1961 Water Agreement by 2011. This ensures

long-term self-sufficiency if necessary. Singapore’s first desalination

plant was commissioned in 2005 to supply 136,000 cubic metres per

day of desalinated water for 20 years.

NEWater is the jewel of Singapore’s diversification strategy. It is

produced through a multi-barrier treatment process that comprises

conventional used water treatment, microfiltration, reverse osmosis

(RO) and finally, ultraviolet disinfection.

To ensure safety, a demonstration plant was opened in 1998 and

operated over two years to test for robustness and reliability, with

more than 20,000 tests carried out for 190 water quality param-

eters. Results showed that quality was well within USEPA and WHO

standards and guidelines. It was also independently verified by an

international and local expert panel. NEWater is now supplied for

non-potable use on a largescale to major industrial complexes,

including wafer fabrication plants, petrochemical complexes,

refineries and power stations. A small percentage is introduced

into reservoirs for indirect potable use. There are now four plants

supplying 15 per cent of demand. When the fifth, and largest plant

is completed in 2010, this will increase to 30 per cent.

Apart from freeing up a large amount of potable water for other

purposes, NEWater has a strategic role in ‘multiplying’ the supply

achieved through recycling. If 50 per cent is recycled supply could

theoretically be doubled. From recycling one drop of water, 0.5

drops could be obtained. This 0.5 can in turn be recycled to get 0.25

and then 0.125 drops, and so on. Theoretically, recycling one drop

Reverse osmosis treatment for NEWater

Bottled NEWater for public education and publicity programmes

Image: PUB