Singapore has kept its levels of water loss fairly low, compared with other developed countries.

According to statistics from national water agency PUB, Singapore's total water loss a year amounts to less than 5 per cent of its total water supply. This includes leaks, metering errors and other forms of water loss.

Mr Chong Kee Sen, former president of the Institution of Engineers, Singapore, said: "Singapore's statistics are comparably low, even when compared with the region and other developed countries."

He said less developed countries in South-east Asia can have water loss levels of 20 to 30 per cent.

Even in developed cities with highly regulated water systems, a considerable amount of water can still be lost yearly. For example, Hong Kong loses roughly 10 per cent of its water supply, and London loses around 20 per cent a year.

Mr Chong said the percentages are not just a reflection of the number of pipe leaks.

"It depends on how fast a city can recover from a leak as well. The more efficient the recovery, the less water will be lost."

For example, Hong Kong had around 260 reported incidents of pipe bursts last year, lower than Singapore's estimate of 330, but it still had higher levels of water loss.

Mr Chong said this could be because Singapore has a quicker response time to water leaks and can stem them before more water is lost.

While Singapore's water loss percentages are relatively low, the city can always do better. It could emulate the city with the lowest level of water loss - Tokyo.

While it is older than and more populated than Singapore, Tokyo has kept its water loss ratio to around 3 per cent.

Mr Chong said: "While PUB has been looking into and using technology to keep the losses low, we can always aspire to do better - fewer leaks and faster recovery - and emulate the good example Tokyo provides."