FOR WEEKS and months after the tsunami, the sleep of the people of the village of Nam Khem was disturbed. Nightmares haunted many survivors in a place where 800 locals perished back in 2004.

Someone would wake up in darkness, terrified, calling out: ''Another wave is coming! Another wave is coming!'' Time and again, the recurring nightmare was quickly spread from house to house.

Wise people headed for the safety of the uplands, just in case. Such is the reality of life on the Andaman's tsunami coast, especially in Phang Nga and Krabi, where most of the 5400 victims who died in Thailand were killed.

Events yesterday at tsunami evacuation drills throughout Phuket and the five other Andaman provinces did nothing to ease the concern of big-wave survivors. Not enough effort has gone into creating and maintaining an effective tsunami warning system.

Phuketwan has harped on about this, long and hard. While a second tsunami is unlikely, it would be foolish to go unprepared. Hawaii's tsunami several decades ago was followed by a second big wave, 14 years later.

Tourists who visit the Andaman coast should ask at their resort: ''Who will wake me up if another big wave comes at 3am?''

Along this beautiful coast on December 26, 2004, about equal numbers of tourists and local residents died. Resorts should be keenest of all to make sure that the system works, and to reassure guests who come to stay that their safety is guaranteed.

Instead, it's mostly left to the residents to simmer about the lack of an adequate system.

Deputy Prime Minister Suthep Thaugsuban chose to visit Nam Khem in Phang Nga for yesterday's drill. This was well-intended and appropriate.

The drill in Patong on Phuket is always carefully contrived for the cameras. It looks real, but it's always formulaic and choreographed. The Deputy PM's decision this year was wise because in terms of casualty numbers, Phang Nga suffered 10 times more pain than Phuket.

Yet rather than relying on a once-a-year evacuation exercise to reassure tourists and residents that all is in order, the authorities need to be constantly reminding everyone that adequate systems and warnings are in place.

For this to happen, the Andaman coast needs not just one warning system but two: the second has to be there and working, just in case the first one fails.

Yesterday's farcical attempt at pretending at least one system is in place did not end the continuing disquiet. The no-sound towers and the towers that broadcast multiple false alarms simply created more uncertainty than ever.

Thailand's tsunami warning system doesn't come close to being effective. Almost six years on, the nightmares continue.