More hazard warnings are needed around Adamasta Rock in the middle of a busy shipping channel in Hong Kong waters to alert passing vessels, an expert says.
The appeal comes as an 87-metre mainland river-trading vessel that ran aground on Adamasta Rock on May 8 is still stranded in the Adamasta Channel. The Marine Department says the ship's owner is organising the salvage plan.
Adamasta Rock, which sits in the middle of the channel between Lantau and Cheung Chau islands and is under water at high tide, has a beacon. There is a red buoy on its right side and a green one on the left.
This is the reverse of the usual setting, in which red buoys are on the port (left) side of a seaway and green buoys on the starboard (right) side. But local sailors and marine professionals are familiar with the quirk.
Ken Wiltshire, vice-commodore of the Discovery Bay Yacht Club, said the buoys could be confusing, especially for first-time visitors.
'The situation could be improved by placing cardinal marks around the obstacle, which would clarify the situation definitively,' he said.
Terry Fung Wah-fuk, a chief instructor at Club Cyclone Runner which provides sailing courses, said he did not see any problem in the design of the red and green buoys.
'The rock, red and green buoys and the direction of buoyage are clearly marked on the nautical chart. It is impossible for mariners to miss the rock, and get confused, if they check the chart.'
But Fung agrees there is a room for improvement. 'I think placing cardinal buoys could help,' he said.
Cardinal buoys are placed to the north, south, east and west of a point of interest, like a wreck.
Lee Chi-wai, chairman of Hong Kong Seamen's Union, said he did not think the red and green buoys at the rock and in the channel caused confusion, and the union had not received any complaints.
Apart from the buoys, the light beacon has a flashing white light that can be seen for 11 nautical miles.
'Investigations into the rare occasions of marine incidents in the Adamasta Channel have not indicated that the marking of the rock played a role, nor is there evidence to date that this is the case in the present grounding,' a department spokesman said.
On May 8, the Zhong Fu Fa Zhan was carrying soil and sand towards Taishan in Guangdong when it ran aground on the rock. None of the seven crew members were injured.
The hull was damaged and water spilled into the cargo hold but there was no danger of sinking.
The Marine Department is still investigating. As the vessel is still stranded there, the department has been broadcasting messages to ships in Hong Kong alerting them about the incident. The Adamasta Channel is mainly used by high-speed passenger ferries and river-trade vessels.