Test water purity - in an office

Straits Times 26 May 09;

WATER purity is key for marine life to survive, and a trio of Hwa Chong Institution students have come up with a fast new way to tell how muddy the waters are.

Instead of trudging down to the waterside to test if there is too much soil in water samples, the 17-year-olds have found a solution in mathematics.

With a single equation, water purity can now be distilled within minutes by analysing digitally downloaded satellite images of the water, all from the comfort of an office.

The team presented its work to about 900 people at Ngee Ann Polytechnic yesterday and bagged the $5,000 top prize and a chance to represent Singapore in the prestigious Stockholm Junior Water Prize in August.

With guidance from their mentor, the trio applied a science model to establish a link between the concentration of soil in a body of water and the amount of light being scattered.

Aside from helping to keep marine life thriving, this relationship will also benefit the water industry because of the impact that cloudy sea water can have on desalination, and on the quality of drinking water in freshwater reservoirs.

On selecting the winning team out of the six in the finals, Dr Ng Wun Jern, chief judge from the Nanyang Environment and Water Research Institute, said: 'The team had a broad view of the scientific problems in their research area. They also took into account the real world.'

The winning team - Kwoh Kai Li, Kuan Hong Nan and Ng Sai Meng - highlighted how inconsistencies in current methods of measurement were a problem in the water industry.

Dr Ng added that the potential to commercialise the idea was promising, because of the pressing need to be able to assess water changes quickly.

This will be the second time that Singapore is taking part in the international competition that pays particular attention to water issues.

The Hwa Chong trio will meet teams from 30 countries around the world.

Hong Nan said Sweden was a dream destination and he hoped that he and his teammates would do Singapore proud.

But when asked what they were going to do with the money, he replied: 'I am too excited to think straight.'

JALELAH ABU BAKER