FERRY companies say new restrictions on boats and ships in Victoria Harbour which come into effect this morning are dangerous and increase the risk of a collision in the congested waters between Central and Tsim Sha Tsui. Some ferry operators were given barely 12 hours warning. But the Marine Department says the change is safe and if the shipping lane was not moved vital work on the western harbour crossing would be delayed for months. The 330-metre wide central fairway which all craft have to use, is being moved closer to Hong Kong's shore to allow engineers to blast away underwater rocks blocking work on the new road tunnel. The new fairway will be narrower. Jeremy Marriott, managing director of Discovery Bay Transportation Services, said vessels would now have less room to manoeuvre. 'You'll just hope that you get through all right,' he said. At the moment vessels could get out of danger by straying slightly over the fairway boundaries because there was about 50 m of clear water on either side, Mr Marriott said. But that would not be possible with the new fairway because of underwater obstructions. A Hong Kong Ferry spokesman said: 'Because the new fairway will be more congested there will be a risk of collision.' But principal marine officer (vessel traffic services) Barrie Hird said the change caused no extra safety risk. Mr Hird said the new route would be safer because ferries would no longer have to turn sharply to get into or out of the ferry terminals. 'Ferries should not be straying outside of the fairway anyway,' Mr Hird said. The lane had to be moved because the construction deadlines for the western harbour crossing were very tight, Mr Hird said. Mr Hird said the move was temporary and would last for eight weeks. The fairway was supposed to move in line with progress on the western harbour and airport railway tunnels, Mr Hird said. But this move was unexpected, and was not in the original schedule. 'We have tried to avoid moving the fairway and we do have some sympathy for the ferry operators,' he said. He agreed there had been a scramble to tell shipping companies what was happening and that the official notice to mariners was only sent out by fax yesterday. 'It has been a bit of a rush,' Mr Hird said. But Mr Marriott said: 'Wonderful. That's the sort of treatment we have to cope with. We didn't know anything about this. 'We are an operator who has been watching out for this. But what about all the others? What steps is the Government taking to tell everybody?' Contractors for the Western Harbour Crossing have applied for a blasting permit for an area 50 m by 300 m to remove rock outcrops and boulders from where the sections for the road tunnel will be laid. A spokesman for the Mass Transit Railway said it was unable to say whether similar boulders would be found on the route of the airport railway tunnel.