Similans tsunami monitoring station operational

PHUKET: The first of nine tide monitoring stations is now operational on the Similan Islands’ Koh Mieng and the remaining eight should be ready within six months, the head of the Royal Thai Navy announced on April 20.

The project was announced this morning by Navy Commander Adm Surin Roengarom, who chaired a meeting with officials from the six tsunami-affected provinces, held at the South Sea Resort Hotel on Karon Beach.

The island-based facilities will monitor sea water levels around the clock for sudden changes in water levels following seismic events and will issue emergency evacuation orders to coastal areas should the possibility of another tsunami arise.

Adm Surin noted that the December 26 tsunami was presaged by a 40-centimeter drop in the sea level in some locations, whereas the March 28 earthquake produced a drop of just 6cm at Koh Mieng, where the monitoring station has been operational on a trial basis since mid-January.

Given Koh Mieng’s remote location, 35 nautical miles off the main coast, detection of a sudden large drop in sea level should provide sufficient time to evacuate vulnerable coastal areas, he said.

He said other proposed locations for such stations included Tapao Noi and Racha Noi islands in Phuket; Sikow Island in Trang; Tarutao Island in Satun; and the Surin Islands in Phang Nga.

Adm Surin said the tide monitoring stations were low-tech, easy to build and inexpensive, though he did not specify the cost or the exact technology used.

The Navy has already assigned a crew of 11 sailors to Koh Mieng to work in shifts monitoring water levels 24 hours a day, with special attention to be paid following reports of earthquakes of 7.0 or larger on the Richter scale. These reports would come from the Earthquake Monitoring Station in Chiang Mai, he said.

For the system to work, evacuations of low-lying areas along the coast would have to take place within 20 minutes, roighly the amount of time it would take for a tsunami wave to reach a drop in water level was detected, he said.

Somporn Patchimpetch, Head of the Ranong Office of Disaster Prevention and Mitigation, joked that he was more concerned about receiving the warning message in time than whether or not an evacuation could take place rapidly.

“On March 28 in Ranong, it only took 14 minutes to get people away from the coast. As soon as people heard the word ‘tsunami’ they jumped up and ran as fast as they could,” he said, bringing a round of laughter from attendees.

Adm Surin also mentioned that the Navy had a long-term plan to deploy sea-level monitoring buoys in locations further offshore, though he did not provide further details.

Many of those present expressed concerned about the failure of mobile phone networks following the tsunami and again after the March 28 earthquake.

Representatives of mobile phone operators AIS, DTAC and Orange who attended said they would raise this issue with their companies’ managements to see if the networks’ reliability could be improved during emergency situations.