SINGAPORE - There has been no discernible uptrend in the number of water pipe leaks that occur here each year.

Senior Minister of State for the Environment and Water Resources Amy Khor told Parliament on Wednesday (Jan 10) that the number of leaks per 100km of pipes has hovered at six a year over the past seven years.

This translates to about 330 leaks each year.

She was responding to a supplementary question by Non-Constituency MP Leon Perera on the trend in the number of pipe leaks.

"That has been the general trend in the numbers, there has been no discernible uptrend in the leak incidence rates," Dr Khor said.

This is down from 2003 to 2004, when there was an average of around 10 leaks per 100km, translating to around 550 leaks in a year.

She added that the rate of pipe leaks in Singapore is among the lowest in the world.

Citing data from other countries and cities, she said the German cities of Berlin and Munich experience seven leaks for every 100km of pipes each year. The eastern region of Britain experiences 13 leaks and Sydney in Australia experiences 28.

Mr Seah Kian Peng (Marine Parade GRC) asked for the cost of installing 320 sensors in Singapore's potable water supply pipelines to detect water leakages.

In reply, Dr Khor said the cost of developing the entire sensor network system, including the 320 sensor stations and the data analytics software, was around $9 million.

The sensor network system allows for real-time monitoring of Singapore's water supply distribution network, and lets the PUB receive real-time alerts on irregular data patterns in water pressure, flow and water quality which may potentially affect supply to customers.

"PUB envisages that the cost of further expanding the sensor network to more parts of Singapore will be lowered as sensing technology improves, and as the initial investment in software development is spread over a larger base of sensors," she said.

Pipe leaks were in the news in November last year after at least five high-profile leaks occurred within a span of two weeks, in areas such as Tampines, Bukit Batok and Serangoon.

PUB had said the vast majority of pipe leaks in Singapore are due to issues such as wear and tear from age, and corrosion from high salinity in the soil.