April 2004
Similan Islands- New deep dive sites and nitrogen testing

Purpose of the project
To search for pinnacles in the deep sea which can be found on sea maps, also to test/compare table/computer diving.

Description of the dive site:
There are a lot of underwater rock formations in the Similan islands, which almost break the surface. Most of them are not suitable for diving on daytrips, as they are too far away or the dive profiles are too deep. We gathered information about 5 of these un-dived underwater rock formations and our purpose was to find dive sites more suitable for technical diving then normal daytrips. The idea was also to compare diving with tables to diving with computers- when doing repetitive deep dives during a single day.

Details of the dive:
We organized a 3 day dive trip to the Similan islands with a team of 7 divers, all who were Raya Divers staff (Janne, Jani, Garry, Dave, Tuomo, Supa and Jari). Because of small technical problems with our boat, we spent the nights on the Similan islands, sleeping in tents. Although we had many problems with air supply, as the generator broke down, all our dives were completed.
The first dives were on the southern side of Elephant Head, close to the underwater rock we found earlier. We found a new peak close by, which came up to 15 meters and had magnificent scenery with swim-throughs and soft coral. We were a little-bit disappointed about the absence of bigger fish, as we had expected to see a lot of sharks, big rays and other interesting creatures. As the peak rises to quite shallow waters, this dive site is fitting for recreational diving.

The next dive was faraway from the normal daytrip routes. About 10 km west from the Similan islands you can see a strange underwater formation on the sea maps. Depth is evenly 70-80 meters all around and in one spot suddenly 28 meters. We were not sure how we are going to find the right spot but thanks to GPS technology and C-MAP electronic sea maps, we found the site almost immediately. The scenery on the dive site was unbelievable: three pinnacles, with diameters of 50 meters, they rose straight up from 70 meters to 25 meters. The place was swarming with schools of fish and gorgeous soft corals. Although no sharks were seen on this dive (members of raya.tek team are shark-fanatics), the dive was exceptionally good. This dive site would be good for trimix diving in 70-80 meters depth.

The next dives were at the northern point of Similan islands. Shark Valley, next to Christmas Point, described in earlier texts, was again up to its reputation so members of the team could enjoy the company of several reef sharks and leopard sharks. Part of the team tried to swim deeper and farther west because nobody had been there before. Strong currents stopped that idea. The maximum depth on the dive was 55 meters and decompression stops were done enjoining Christmas Point’s magnificent scenery. This dive site is the most dangerous of Similans areas if you have no earlier experience in sudden currents “sucking” you down.

North Point is known as a good dive spot and so we went to explore what the deeper parts of it have to offer. Our team decided that this was the best dive of the trip, as the visibility was 40 meters and no current at all. Gorgeous wall of corals went down to 60 meters offering also a few swim-throughs. There was an enormous amount of fish and quite a few reef sharks as well as leopard sharks swimming around in the deep water.

Koh Bon is well known for big manta rays and the purpose of the next dive was to explore the underwater rock formation next to it (Koh Bon Pinnacle). This site is often dived during daytrips and live-aboard trips, so our purpose was to research the deeper parts of the site. Coral covered rock went down to 50 meters. To our annoyance we discovered that illegal fishermen had left a huge fishing net bundled tightly around the whole dive site. We tried to cut it loose though we did not succeed as we did not have enough equipment for this kind of a project. Together with other Khao Lak dive centers the net was cleaned off later. On that project Tuomo “Tupi” Vauhkonen represented Raya Divers.

The last dive of this trip was done at the famous Koh Tachai, situated north from the Similan islands. As everybody had already done a lot of deep and physically demanding dives, most of the team decided to enjoy a normal recreational dive. Janne and Tuomo(who have dived at the Similans more than allowed by law…), decided to look around the unexplored northern part of the island. They didn’t find fish or corals in the same abundance as on the southern side of island.

On a whole, this 3 day trip succeeded very well and everybody was satisfied with the outcome and with the dives made. Raya.tek has written down new locations of many untouched dive sites, which not many people have any knowledge of...

Gases used:
Air, EAN 32, deco-gases EAN 50 and EAN 60

Equipment used:
Wetsuit 5mm
2 X 12L aluminum 200 bar tnks (+mixed set of different double-tanks set-ups)
1 X 12L aluminum 200 bar deko-tank
2 X ScubaPro MK25 + S600 regulator
Diverite backplate, harness, wings
Reel + SMB