Thammarat, an officer at the station, says the water level today was much higher than yesterday and admits the station itself could soon be flooded.

He says they will not evacuate the station. If it is flooded, he says, they will have to work constantly to pump out the water. He says they must be prepared because they cannot abandon the equipment. He repeats they will not evacuate.

While residents near the river and swollen drainage canals are already getting wet, most of central Bangkok is still dry. But many businesses are now racing to prepare for the water.

On a busy downtown street, workers layer cement and stack cinder blocks in front of small shops, building up waist-high walls.

Across the street, a monstrous three-meter-high wall of sandbags is protecting a bank.

As more residents jammed highways and bus terminals for coastal areas or the mountains, sandbag and cement walls sprung up throughout the city.

Thai authorities say it is only a matter of time before flood waters seep into central Bangkok, though it is still not clear how widespread or deep they could get.