SINGAPORE: With a monsoon surge forecast to bring rainy and windy weather to Singapore over four days from Friday (Jan 10), national water agency PUB has warned that flash floods could occur. 

There were already instances of flooding in the last two months of 2024 amid heavy rain, with scenes of cars driving through the waters. 

What should you do if your vehicle is caught in a flash flood? Are there safety procedures for public buses and commuters?

CNA takes a look at some safety tips, as well as the guidelines from transport operators.

Should I drive through floodwaters?

Avoid driving through floodwaters as much as possible. As a general rule, do not attempt to drive through water deeper than 15cm (6 inches), or above kerb height.

There are several dangers of pushing through floods, such as the risk of engines stalling.

"If water enters the engine through the intake or air filter, it can cause the engine to seize, potentially resulting in catastrophic damage," said Mr Wong Che Wey, regional technical training manager of Motul Asia Pacific, which manufactures products for engines.

Floodwaters can also affect a vehicle’s electronics, he said, adding that control units mounted on a vehicle’s floor panels are the most vulnerable when water enters the cabin. 

Mr Jake Ler, chief marketing officer at motoring platform Motorist, pointed out that travelling through floodwaters placed drivers at risk of "aquaplaning". 

This is when tyres lose traction on a wet surface, leading to a loss of control, he explained. 

"Additionally, hidden dangers such as potholes, debris or uneven road surfaces submerged in the water can cause unexpected damage or accidents," Mr Ler said.

What if I can't find an alternative route?

If an alternative route isn’t possible and the road appears passable, drivers should carefully evaluate the situation.

Motorists should consider the water depth and their vehicle type, Mr Ler said, pointing out that some vehicles such as an SUV might be better suited for passing through the waters compared to a low-slung sedan. 

If the conditions allow for it, drivers should engage their low gear...