200516 Tsunami Escape

Tsunami Escape
MARS Report 200516

I was serving as an officer on board a yacht. Boxing Day, December 2004 was a normal day for us with charter guests onboard, we were quietly lying to our port anchor in approximately 8 metres of water in a bay off the coast of Thailand. Our normal day started at 0800 and, at 0835, I was taken ashore to refill the jerry cans with petrol for the jet skis. This took almost 40 minutes and once I arrived back at the pontoon, I radioed the vessel and a tender was sent to pick me up. Three other crew members came in on the tender to get rid of some garbage that had to be removed from the vessel. The tender came in almost all the way to the beach as the tide was high. The moon was full, hence the tides were larger than normal.

We all returned to the vessel within the next 15 minutes. Once onboard, I did some minor tasks but, within the next 25 minutes, I noticed that the 'tide had gone out'. I mean I was almost looking up at the pontoon on the shore where we were standing a short time before. How could this be? I also noticed that we had a wake coming off the stern of our tenders which were lying alongside. I immediately went to the Bridge and discussed my concern with the Chief Officer as to what was happening with the tides, then I looked at the depth sounder - it said 2.8 metres! The Captain came onto the bridge to hear our concerns and instantly started the main engines. I went to the foredeck to heave in the anchor. I noticed that the anchor cable was almost horizontal and literally bouncing with a lot of tension.

Once the engines were running, I began heaving in our port anchor but it was slow going at the start, especially as we were dragging at a fast rate backwards towards the beach. Once the snubber was on deck, it was cut and the anchor was now leading directly aft as we were going ahead on the engines in order to get into deeper water. We got the anchor onboard and the swim platform doors shut just in time as the first backwash swell was heading back towards our stern. It pushed us sideways, one of our tenders had snapped its bowline but quick action by a deckhand kept it from getting lost or further damaged. Viewed later on our chart plotter, the Track History showed we dragged anchor some 654 metres in a 7 minute time frame, that's almost 6.5 knots backwards! The surge and sheer water movement in the bay was amazing. We headed out to sea as quickly as possible with many other boats and jet skis following. The sound of the waves hitting the shore was like explosions as cars, buses and hotels were smashed, dislodged and sent on their way, boats were being thrown high and dry leaning on their sides on the street.

A series of waves struck but our quick action put us into safe water with no time to spare. We watched in awe as the sea unleashed its fury on the coastline as we safely navigated into safe water. We spent a very vigilant night at anchor in deep water off the coast.