"A Vertical Wreck! Honest!…"

It was April 1998. Mermaid's Dive School of Pattaya had arranged an exploration trip to 3 sunken warship in the Gulf of Thailand, close to the coast at Prachuab Kirikhan. The trip has been a smashing success. We had found and dived 3 old Thai Navy vessels, sunk for target practice in the early 1970's, and although the diving was no better than usual in the Gulf (bad visibility, little life), we were all thrilled enough with just having dived something new. The Hardeep and the Bremen, while fine wrecks, were getting a bit stale, and we had long been on the look-out for other wrecks, of which we knew there to be plenty in Thai waters. Steve Blumenthal of Mermaid's had finally made contact with a captain who makes a living taking tourists deep-sea fishing, and he claimed to know of numerous uncharted wrecks, which he took his clients to.

So far, he had certainly made good on that claim, but this outrageous suggestion, that somewhere in Thai waters there existed a wreck that actually sat vertically in the water column, stretched credibility. How does a wreck sit vertically in the water ? Did it embed itself in the bottom ? Did it founder on a pinnacle and slide down the side of the rock ? All sorts of theories were coined, including one holding that the captain must be getting a bit old, to put it kindly.

But considering that he had after all just taken us to 3 wrecks none of us had ever heard of, and done so in a manner that suggested that he could have done it blindfolded, Mermaid's Dive Center decided to take a chance and arrange an exploration trip. The fact that he claimed it was sitting in gin-clear water (yeah, right, in the Gulf of Thailand ?), and was teeming with fish, whetted our appetites.

So we took off in the evening of Monday, May 4th 1998. We knew nothing of the wreck, other than that the captain said it was there. Details such as identity, depth, state of the wreck, currents, even exact location, were unknown to us, and since the boat does not have a compressor, the trip was further complicated by the fact that all gas had to be brought along pre-pumped. There was only one Trimix-certified diver onboard, so we used air, EAN32, EAN 35 and EAN 36, and had to accept from the beginning that we would probably not be able to go all the way to the bottom. The nearest chamber is in Sattahip, a long way from the area around Koh Chang that the captain had loosely indicated as the location, and so we did not anticipate doing any decompression dives either, although we were prepared to play it by ear.

As the boat steamed southwards and then made a turn to the east, hugging the coast of the Thai Eastern Seaboard, we settled in on the deck of the boat, alcohol was consumed in mild doses, and everyone tried to convince everyone else that there was no way this wreck could exist. Around midnight, we turned in, each with a mattress, a pillow and a blanket, and awoke roughly 8 hours later, to the captain's terse announcement: "Five minutes!"

We were in the middle of nowhere. There were indeed some makeshift markers in the water, but apart from that we were alone. There was nothing to see�except for a dark shape just below the surface of the ink-blue water�

A call went out for a volunteer to snorkel out and tie the boat to the wreck. I was in the water in less than a minute! The sea was calm, the sun was shining, and there below me was the most amazing sight. A ship, clearly a tanker of some sort, judging from the bulbous storage tank on the deck, sitting perfectly vertically in the water column. Schools of batfish and yellowtail were all over the place!

Sitting on its derriere, the only point of possible penetration, the superstructure, is of course located further down, and naturally we had to take a look.

The top of the superstructure (well, the front, really) begins at 46 meters. Very strange feeling to stand there, on the front bulkhead, looking up at the deck rising above you! I have made 10 dives on the wreck now, and on the last 4, I've started seeing the guardians of the wreck: The area around the superstructure is home to the 3 largest groupers I have ever seen and am ever likely to see! These fish have to be seen to be believed, but I have reliable witnesses - including Trimix divers, so don't blame it on narcosis. Most of us estimate that these are 300-kilo groupers! They are very inquisitive, which can be pretty intimidating, but so far have proven to be completely harmless.

We have also made it to the bottom, and this area is being visited increasingly often, both by air- and trimix divers. The bottom is at 59.8 meters, and consists of very fine silt, consistent with the general area around Koh Chang. Part of the explanation for the wreck's bizarre position is found here. It is almost certain that the storage tanks on the deck are empty, and on this type of vessel, the engines are located aft, putting the center of gravity such that she would logically have sunk stern-first. She hit the bottom hard, and embedded herself there, almost all the way up to the smokestack. So there is a good 5-6 meters of ship below the bottom, and this combined with the buoyancy of the empty tanks contribute to her bizarre position. The lack of any noticeable current in the area certainly helps, and it is likely that she will remain vertical for a long time, since the tanks are made from stainless steel and will only rust very slowly.

So who was she ? What happened ? We don't know it all, but we do know that her name was originally "Koho Maru No. 5", and that she was sold or chartered to Thai operators, because her original name has been painted over with Thai characters. Of "Koho Maru No. 5", we know the following: She was built at the Ura Kyodo Shipyards in Japan as Hull Number 300, and launched on December 1st 1994. Registered as a Kurashi-type tanker vessel with a deadweight tonnage of 1,250 metric tons and a Gross Registered Tonnage of 498 metric tons, she was powered by a 6LH28 engine capable of approximately 12 knots service speed. Her length was (is) 64.40 meters on a beam of 10.2.

Neither Lloyd's Archives nor Casualty On-Line offers any clue as to what happened. This is not unexpected, given that she seems to have ended her brief career sailing under Thai Flag, but commercial divers from Mermaid's Marine claim that she capsized in a bad storm, and allegedly took 10 hands with her. The search for facts continues.