SINGAPORE - National water agency PUB has been stepping up flood prevention measures since October, to meet the increased likelihood of flash floods.

The measures include sending out advisories to residents and businesses in flood-prone areas, stepping up inspections of construction sites near drains and canals, as well as increasing checks on critical areas such as road tunnels, vehicular underpasses and flood barriers for Orchard Road developments.

At a briefing on Monday (Nov 13), PUB said it will focus more on construction sites with major canals running through them.

Mr Choy Wai Kwong, chief engineer for drainage operations at PUB, said 28 sites have been identified, including the work site in Stagmont Ring near Choa Chu Kang.

These sites have major drains going through them, so there will be a much larger impact, he said. "If there is a blockage, it will disrupt the flow of more minor drains, causing floods to affect more areas," he added.

Higher rainfall is expected during the north-east monsoon season, which typically lasts from October to March.

In the past three years, Singapore has averaged nine flood-days a year, with levels reaching up to about 200 to 300 mm in specific spots.