Let's talk dirty! How survives a city-state of five million
citizens that has no freshwater, insignificant groundwater resources and even
less land to store rainwater?
Singapore had to deal with this problem, as its 50-year water
supply agreement with Malaysia ended in 2011.
"About 50% of the Island’s fresh water supplies are imported from Malaysia which is subjected to ongoing negotiations." (NEWater, 2002)
NEWater a
Way to self-reliance
Here, no
sewers that flow into the sea, Singapore has developed the NEWater project for
wastewater. The project has the capacity to cover 30% of needs and is expected
to triple in the next 50 years. The city-state aims to be completely water independent in 2060.
Singapore NEWater developed various physical, chemical and microbiological tests within
two years, to ensure that NEWater is potable and safe (NEWater, 2002).
Purification process
Singapore includes six treatment
plants wastewater that will be gradually replaced by one that will collect the
bulk of the waste water from the island by a long deep pipeline, Deep
Tunnel Sewage System, crossing the whole island North to South. The water
is treated through micro or ultra-filtration, reverse osmosis and irradiation
with ultraviolet radiation. Aravinthan (2005) described this process as
"indirect potable reuse provided” .
 |
| FIGURE 2: Planned Indirect Potable Reuse, (Aravinthan, 2005) |
Planned indirect
potable reuse will increase natural water reserve including river,
lake, reservoir, and aquifer or the incoming needs. As exposed below, the wastewater discharged
will be exposed to high degree of treatment with various filters to
eliminate the pollutants before the introduction into the natural water supply
sources. (Aravinthan, 2005, see further reading Lal Seth, 2011)
The wastewater
treatment plan is a good solution. Nevertheless, this project is very expensive
for a state like Singapore. Moreover, the treatment process consume a lot of
energy and chemicals. Is the project viable in the long term?
[ Want to Know More? ]
(1) Vasantha Aravinthan, 2005, Reclaimed Wastewater as a Resource
for Sustainable Water Management
(2) LAL SETH Bharat,2011, "Singapore taps its water",
Down to Earth,
http://www.downtoearth.org.in/content/singapore-taps-its-water
(3)NEWater, 2002, Singapore Water Reclamation Study. Expert
Panel Review and Findings, http://www.pub.gov.sg/water/newater/NEWaterOverview/Documents/review.pdf
(4) PUAH Aik Num, 2011, "Smart Water – Case study of
Singapour", PUB rapport.