Why MRT not affected by Orchard Flood

Been wondering why Orchard MRT was not flooded when the flash flood hits Orchard Road on 16th June. Turn out that:

That’s because the Orchard MRT station had measures like entrances that were built at least one metre above flood level.

SMRT staff are also trained to handle emergency situations.

Currently, stations at Orchard and City Hall are the only ones equipped with a water—level detecting system.

But SMRT said all its stations are designed to withstand flooding...

[Source: Xin MSN]

Come to think of it, most (if not all) of the entrance to underground stations are at least one metre above ground. Didn't notice that previously.

This is what I call first class design. SMRT management and system engineers did their job well have thought throughly the possible threats that might affect underground train services.