Port marks (red) define one side of the channel. They have a can-shaped topmark or buoy. If lit, they display a flashing red light.
Starboard marks (green) define the other side of the channel. They have a cone (triangle) topmark or buoy. If lit, they display a flashing green light.
Lateral marks in pairs
When port marks and starboard marks are near each other – in a pair – you should travel between the two.
Single lateral marks
If there's a single mark, the safe side to pass depends on whether you're travelling upstream (away from the sea) or downstream (towards the sea).
Single port marks (red)
When you travel upstream, keep port marks on your port (left) side.
When you travel downstream, keep port marks on your starboard (right) side.
Single starboard marks (green)
When you travel upstream, keep starboard marks on your starboard (right) side.
When you travel downstream, keep starboard marks on your port (left) side.
Use your vessel's sidelights to help you remember: green to green when going upstream, green to red when seas are ahead.
Lead marks (leads) guide you into a port or through sections of a waterway to avoid hazards. They are commonly used for crossing coastal bars and in shipping ports.
Lead marks are made up of 2 marks: one in the foreground and the other behind and above it. They are usually lit at night.
To keep your vessel in safe water:
- line up the 2 marks, one above the other
- travel directly towards or away from the lined-up marks.
Sector lights and directional lights
Similar to lead marks, sector lights guide you into a port or through sections of a waterway. They use coloured lights to show the safe 'sector'.
For example, sector lights on the coast may display 1 colour to vessels coming from the south-east and another colour to vessels coming from the north-east of the light.
Sometimes there are 3 different sectors, each with a different colour.
Isolated danger marks
An isolated danger mark shows a specific danger – for example, a wreck – surrounded by generally safe water.
The mark is black with a red band in the middle. It has 2 round black topmarks. If lit, it displays a white light flashing in a pattern of 2 flashes.
You can pass an isolated danger mark on any side, but not too close.
These yellow marks show special features or areas, such as:
- tide poles – graduated posts that measure the rise and fall of the tide
- spoil grounds – areas for waste, such as dredged material
- underwater pipes.
Safe water marks
These marks are used to show there is navigable water all around them. They may be used to separate traffic in large shipping channels. They are not common in NSW, but there is one off Bradleys Head on Sydney Harbour.
Safe water marks have red and white vertical stripes. They may be round, pillar-shaped or spar-shaped, and may have a red, round topmark.
Aquamark minibuoys are used in some areas instead of conventional marks.
They are small red, yellow or green buoys, and often have messages on them that you must follow.
You will see 3 shapes in a vertical line, from top to bottom: ball, cone, ball.
At night they are lit, from top to bottom: red, green, red.
Channel blocked or closed signals
These signals are used to show when a:
- bridge span is blocked
- channel is blocked
- port is closed.