Navigation Rules

Navigation rules are often called ‘rules of the road at sea’ and apply to all boats. These rules give clear indication about passing, approaching, giving way and overtaking other boats.

Everyone using the waterways should familiarise themselves with the International Rules for Preventing Collisions at Sea (Col Regs) and become aware of the basic rules on the water.

You should always make your movements clear and deliberate so that other masters can see your intentions. Never assume the master of another boat will observe the rules – always be prepared to take action to avoid a collision.

 A good lookout through sight and sound must be kept at all times.

The master is responsible for keeping a lookout for dangers. Be aware of the boating environment, especially in bad weather, restricted visibility and darkness.



Vessels operating from sunset to sunrise, whether at anchor or underway, must carry and exhibit the correct lights. A vessel is underway when it is not anchored, moored or tied to the shore.

Navigation lights must also be displayed during daylight hours in periods of restricted visibility.

Spotlights can be used to identify specific hazards, but this should only be done when operating at very slow speed and without affecting other waterway users. It is unsafe to navigate a vessel with light illuminating the water directly ahead because it deprives you and other vessel operators of night vision. It is important to slow down and keep a good lookout.


  • Background lighting on the shore can cause confusion
  • All vessels are required to show some form of lighting
  • A safe speed is a speed at which sufficient action can be taken in time
  • Some vessels moored in approved mooring areas and oyster leases may not be lit.

Power-driven vessels less than 12 metres in length that are underway must show the following lights:

  • a masthead light, sidelights and a stern light, or
  • an all-round white light (visible from 360 degrees), and sidelights.

A power-driven vessel of less than 7 metres in length, whose maximum speed does not exceed 7 knots, may exhibit an all-round white light only and, if practicable, also exhibit sidelights.

Anchored vessels less than 50 metres in length must show an all-round white light. Remember that anchoring in narrow channels and obstructing traffic is prohibited.

Drifting vessels must show the same navigation lights as if they were still making way. For example, if a power driven vessel is drifting it must show its white light.

Rowed or sailing vessels less than 7 metres long must as a minimum have a torch or lantern showing a white light ready to display in time to prevent collision.

Sailing vessels 7 metres or more must show sidelights and a sternlight when underway.

Sailing vessels propelled by engines are considered as power-driven vessels under the regulations and consequently MUST display the same lights.

Vessels with restricted manoeuvrability are required to exhibit the following lights and shapes:

  • three all-round lights in a vertical line with the highest and lowest of these lights being red in colour, while the middle light shall be white.
  • three shapes in a vertical line with the highest and lowest of these shapes being balls and the middle one a diamond

Should the vessel be making way through the water whilst involved in such operations, then a masthead light, sidelights and a stern light are also required.

These vessels could be involved in such operations as fishing or in particular dredging, which occurs on several waterways around the State.






Navigation marks are the equivalent of road signs on a highway. It is important to be aware of what is meant by the various marks.

Types of Marks

  • Lateral Marks : indicate the edge of a channel
  • Cardinal Marks : indicate the position of a hazard and the direction of safe water
  • Isolated Danger Marks : indicate a hazard to shipping
  • Safe Water Marks – indicates the end of a channel and deep, safe water is ahead
  • Special Marks: indicate an area or feature such as speed restrictions or mooring area

Take time to study a chart and buoyage to familiarise yourself with the navigation channel. For further information on safe navigation see the IALA website.

Lateral Marks

Port and starboard marks are referred to as lateral marks.  Port hand marks are painted red and have a can-shaped topmark or buoy. If lit, a port hand mark shows a flashing red light.


Port Lateral Marks

Port Lateral Marks

Starboard hand marks are painted green and have a cone-shaped topmark or buoy. If lit, a starboard hand mark shows a flashing green light. When both a port and starboard hand mark are placed near to each other you travel between the two of them.

Starboard Lateral Marks

Starboard Lateral Marks

Single Lateral Marks

Often lateral marks are not placed in pairs, so you will need to decide on the safe side to pass. The safe side to pass a lateral navigation marker is determined by your direction of travel to or from the sea.


Single Lateral Marks

Single Lateral Marks


The coming in and going out rule

Upon entering harbour the port (red) mark should be passed on the boat’s port (left) side, while the starboard (green) mark should be passed on the boat’s starboard (right) side.

When leaving harbour the port (red) mark should be passed on the boat’s starboard (right) side, while the starboard (green) mark should be passed on the boat’s port (left) side.

coming in and going out

coming in and going out


 Lead Marks

Lead marks are a method used to define the correct course to be steered when in waters containing navigation hazards. They are often used to mark the correct approach to a navigation channel, which is then defined by lateral marks. The lead marks are two separate navigation aids (one in the foreground and one placed further back on the shore) which, when aligned, provide the correct course for the vessel to steer. Lead marks may be day marks or may be lit for night use.

The day marks are normally two triangles. To steer the correct course the boat should be manoeuvred so that the apex (point) of each triangle comes into alignment.


Lead Marks

Lead Marks


Isolated Danger Marks

These marks indicate dangers of limited extent with navigable waters all around them. You can pass them on any side, but do not pass too close. If lit, it shows a white light flashing in groups of two.


Isolated Danger Mark

Isolated Danger Mark


Special Marks

Special marks are yellow and indicate special features or areas such as tide poles, spoil grounds or underwater pipes. They are more commonly used in Tasmania to highlight fish farm boundaries. These farms vary in appearance and include fish cages, submerged lines and oyster racks. They all pose a hazard to navigation if vessels enter the farm perimeter. Marine farm navigation marks may be lit or unlit depending on the situation, but when lit, they show a yellow light.


Special Mark

Special Mark


Safe Water Marks

These are not common in Tasmania.

However, they may be used to mark areas for commercial shipping. They show a white light at night and can be passed on any side.

Safe Water Marks

Safe Water Marks


Overhead Power Lines

Clearance heights vary with water level. It is most important that you know the height of your mast and understand the height level given on any sign. Clearance of power lines is usually given as the clearance above MHWS (Mean High Water Spring or the average of very high tides). This height may reduce during king tides or floods. Extra caution is required when launching/retrieving vessels with a mast. Always keep a lookout for overhead power lines.

Submarine cables

Anchoring is prohibited near submarine cables. If an anchor becomes snagged near one of these signs, it should NOT be retrieved – cut the line.


Submarine Cables

Submarine Cables


Cardinal Marks

Cardinal marks are used to indicate that deeper water lies in a compass direction away from a danger such as a reef and shallow areas.


Cardinal Marks

Cardinal Marks




The chartlet shows the new sector lights established as a leading line into the Leven River. The sector lights operate day and night and have a day range of 0.85nm which is well beyond the training walls. An orange dayboard has been established on the structure so mariners can more easily identify the lights during daytime operations.

Upon approaching the river entrance, mariners should remain on a course so that the white light remains visible which indicates that they are tracking on the leading line. When the observed light changes from white to green, the vessel is West of the leading line and a course alteration should be made. When the observed light changes from white to red, the vessel is East of the leading line and a course alteration should be made.

Guide to Ulverstone Leading Lights 02

Leven River Leads







MAST has produced the Safe Boating –  Buoyage System sticker

These can be obtained from MAST Office or your local marine dealer.

150489 MAST Safe Boating adhesive label_v5


Buoyage sticker



Special sound signals exist for vessels to indicate their manoeuvring intentions when they are in sight of one another

  • 1 short blast  – I am altering course to starboard
  • 2 short blasts – I am altering course to port
  • 3 short blasts – I am operating engines astern (stopping)
  • 5 or more short blasts – I am unsure of your intentions and I doubt whether you are  taking sufficient action to avoid collision


International Code Flag “A”

The international Code Flag “A” is a blue and white vertically divided flag that indicates divers below. When displayed, this flag requires that boats do not exceed 5 knots when within 120 metres of it. This flag may be hoisted from an anchored vessel, on a buoy or dive float or hoisted on the shore.

Operation in Pilotage Areas

Recreational vessels often operate in shipping ports and channels. Small craft operators must be aware that large ships cannot alter course or speed quickly and often their draft restricts them to a very specific course. In addition, it is difficult to even observe small craft from the bridges of certain ships.

International Code Flag “H”

The international Code Flag “H” is a red and white vertically divided flag that indicates that the vessel has a pilot on board. This flag is used when ships are approaching their berth and are under the control of a pilot. In such circumstances, the recreational skipper must keep clear of the ship at all times.

Vessel under Control of Exempt Master

Ships that enter ports regularly are occasionally exempt from using a pilot, however they still have right of way over all other craft. To indicate that they are under the control of an exempt master, these ships will display an all-white square flag.