New vehicles, tech help PUB respond faster to flash floods

Motorists and pedestrians caught in flash floods this year may have spotted some yellow vehicles at the flood zone, flashing an LED warning about deep water ahead.

These are from a new fleet of 13 flood response vehicles - unveiled yesterday alongside other enhanced forecasting and monitoring technology - that will help national water agency PUB respond to flood situations more quickly.

These vehicles can move through water 70cm high, or slightly above the average knee level, and are fitted with cameras that live-stream footage back to PUB's Joint Operations Centre. They also carry flood mitigation equipment such as flood barricades.

Flash floods in Singapore have generally not exceeded 50cm.

PUB acknowledged that climate change will bring about more frequent and intense rainfall, which could put a strain on the island's drainage capacity.

The agency also announced that it has doubled the number of radars used in monitoring and forecasting rainfall across the island from three to six.

"(This) creates a more robust monitoring network with greater coverage, improving the accuracy of our rainfall measurements and forecasts... enabling PUB to issue public alerts and deploy resources to potential flood locations in a timelier manner," said the agency.

Machine learning will improve the system's accuracy to up to 80 per cent by early next year, from 65 per cent now.

"We are given 30 minutes to reach the site before it floods or even before it rains," said Mr Abdul Aziz Abdul Rahman, a senior assistant engineer with the quick response teams that use the new flood response vehicles.

"We chase the rain," he added.

Flash floods in Singapore usually last less than an hour and are caused mainly by intense deluges.

Although the quick response teams have been around for many years, officers used to drive to flood sites in PUB vans, said Mr Lee Cai Jie, chief engineer of drainage operations at PUB's catchment and waterways department.

"Previously, the vehicles were not optimised for flood response," he said. "(The new ones) can wade through the water to render assistance to stranded vehicles."

PUB has also combined the data from the new vehicles, the radars, flood detection tools such as water-level sensors, as well as closed-circuit television (CCTV) cameras islandwide into one integrated dashboard.

Having all the information on one dashboard allows staff to concentrate better and make decisions faster, without having to pull out different data sets, said Mr Lee.

The integrated dashboard builds on PUB's existing system that monitors reservoir and drainage operations in real time.

Mr Yeo Keng Soon, director of PUB's catchment and waterways department, said that while improvements to Singapore's drainage system are ongoing, it is impossible to cater to every extreme rainfall event and eliminate floods.

It is thus vital to be more prepared for floods and equip buildings with flood barriers, he added.

As at Sept 30, there were 31 ongoing drainage improvement projects and road-raising works, with eight upcoming projects.

PUB has also successfully trialled a new automatic flood barrier at a condominium along Tampines Road near Hougang that has been affected by flash floods in recent years.

This is a more permanent solution to shield commercial buildings and apartment blocks from storm water, compared with PUB's existing suite of portable flood barriers.

Building owners interested in learning more about the automatic flood barrier can contact PUB.

The agency said it will continue to enhance its flood response measures as climate change leads to more erratic weather patterns.

For instance, the islandwide network of water-level sensors and CCTV cameras will be expanded.

"With the uncertainty of the climate, that's the only way to move forward," said Mr Lee.

Correction note: In an earlier version of the story, we said Fortune Park condominium was located in Tampines. This is incorrect. The condominium is located along Tampines Road. We are sorry for the error.