Marine Safety

The Northern Territory Safety Guide for Pleasure Craft

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Contents
Minimum safety equipment for pleasure craft
About the Marine Safety Branch
Boating rules in the NT
Regulations Pleasure craft Exemptions and exempt areas Water skiers and divers Small craft Restricted areas and anchoring
Safety checks for pleasure craft
Flotation in boats
NT Police Marine & Fisheries Enforcement Unit
Recreation boating courses
Anchors and anchoring
Common types of anchors
Signals
Marine emergency procedures
Distress signals
EPIRBs - safety via satellite
Flares
Avoiding collisions
Courtesy for all water users
Navigation lights (small vessels)
Buoys, beacons & marks
Fire prevention and safety afloat Some common causes of fire aboard small craft Refuelling your boat LP Gas
Marine pollution
Marine communications for pleasure craft
Radio operational procedures Distress call Urgency and safety calls Weather Marine communications equipment licensing Mobile phones and satellite phones
Tidal information
Tidal variations for various rivers
Guide to tidal abbreviations
Guide to tidal planes
Guide to recreational fishing in the NT
List of gazetted sheltered waters
Public boat ramps in the Darwin area

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Minimum safety equipment
for pleasure craft under 5 metres and 5 to 10 metres

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About the Marine Safety Branch

The Marine Safety Branch of the Department of Planning and Infrastructure is responsible for marine safety and pollution regulation matters in the Northern Territory. The aim is to ensure boating is both safe and enjoyable. This is achieved through education, regulation and the sponsorship of facilities such as navigation aids.

The Marine Act and Regulations cover the construction, survey and safety equipment on commercial vessels, tourist vessels, hire and drive vessels and regulate safe boating practices for pleasure craft.

The Marine Safety Branch works together with industry in the Northern Territory to ensure the correct number of qualified persons needed to operate commercial vessels safely are always on board.

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Boating rules in the NT

Pleasure craft do not require registration and operators are not required to hold a licence to drive a pleasure craft.

However, minimum requirements for safety equipment have been determined for most pleasure craft.

It is important that operators familiarise themselves with the Marine (Pleasure Craft) Regulations in regard to safety equipment requirements, including exemptions that are applicable.

NT Marine and Fisheries Police and Marine Safety Branch Boating Safety Inspectors conduct frequent patrols at boat ramps and on the water.

View copies of the Regulations and the NT Marine Act.

There are penalties for not complying with these regulations.

Check your safety equipment and carry the required amount under the regulations. Ensure it is in good condition, of regulation standard and is stowed properly.

Interstate marine authorities

For further information regarding requirements for pleasure craft in other States contact the appropriate government.

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Regulations

Pleasure Craft

Definitions

In the regulations, unless the contrary intention appears:

Anchor cable means a short link chain or rope to which not less than 3 metres of chain cable is shackled between that rope and anchor attached to it.

Approved means approved by the Director, Marine Safety Branch, Planning and Infrastructure.

Boating Inspector means a person appointed under Regulation 6 (1) by the Minister.

Length in relation to a pleasure craft means the greater distance between the foremost and aftermost parts of the vessel measured in a straight line parallel to its keel.

Sea includes every arm, estuary or river, which is part of the sea and is within the ebb and flow of the tide at ordinary spring tides.

Serviceable in relation to a pleasure craft or tender, means the hull and all the fittings of the pleasure craft or tender and safety equipment carried on it are:

1. sound in condition; and
2. ready and suitable for immediate use.

Tender means an auxiliary vessel that is used solely for or as a means of transportation between a pleasure craft and the shore.

‘V’ distress sheet means a sheet of canvas or other equally robust material of a fluorescent orange/red colour bearing the letter ‘V’ in black, being a sheet not less than 1.8m x 1.2m in size capable of being securely fastened down so as to be visible from the air, with the letter ‘V’ being not less than 800mm in height with the strokes forming the letter ‘V’ being not less than 130mm in breadth.

Nautical Mile – is a sea mile approximately 1850 metres.

Knot – is the nautical measure of speed. 1 knot is equivalent to a speed of 1.85 kilometre per hour.

Safety standards for the operation of pleasure craft or tenders

A person shall not operate a pleasure craft or tender at sea unless it is:

1. Serviceable;
2. Seaworthy for the purpose for which it is operated;
3. Not overloaded;
4. Provided with a means or carries equipment which will enable a person who has fallen into the sea from the pleasure craft or tender to reboard it; and
5. Carries the prescribed safety equipment

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Safety equipment requirements

1. Pleasure craft under 5 metres in length:

   1. one approved lifejacket or buoyancy vest for each person on board; – See Note 2
   2. two paddles or oars fitted with rowlocks;
   3. one bailer with lanyard;
   4. one anchor fitted with an anchor cable of not less than 50 metre;
   5. one litre for each person on board of fresh drinking water in a leakproof container;
   6. one waterproof torch or lantern;
   7. two red flares; – See Note 1
   8. two orange smoke signals; – See Note 1
2. Pleasure craft of 5 metres to 10 metres in length:
   1. one approved lifejacket or buoyancy vest for each person on board; – See Note 2
   2. one bailer with lanyard or bilge pump;
   3. one anchor fitted with an anchor cable of not less than 50 metre;
   4. one portable fire extinguisher; – See Note 1
   5. one litre for each person on board of fresh drinking water in a leak-proof container;
   6. one waterproof torch or lantern;
   7. two red flares; – See Note 1
   8. two orange smoke signals; – See Note 1
   9. one “V” distress sheet;
   10. one liquid damped compass;
   11. one chart of the area of operation.
3. Pleasure craft of more than 10 metres in length:
   1. one approved lifejacket or buoyancy vest for each person on board; – See Note 2
   2. one bilge pump with a minimum capacity of 100 litres per minute;
   3. two anchors, each fitted to an anchor cable of not less than 50 metre;
   4. two portable fire extinguishers; – See Note 1
   5. two buckets, each of not less than 9 litre capacity and fitted with a lanyard;
   6. one litre for each person on board of fresh drinking water in a leak-proof container;
   7. one waterproof torch or lantern;
   8. two red flares; – See Note 1
   9. two orange smoke signals; – See Note 1
   10. one “V” distress sheet;
   11. one liquid damped compass;
   12. one chart of the area of operation;
   13. one lifebuoy fitted with buoyant line.

   EPIRB (For all lengths) – One (1) 121.5/243MHz or 406MHz Emergency Position Indicating Radio Beacon (EPIRB) must be carried onboard if the vessel is operating outside sheltered waters and more than 2 nautical miles from the coast.

4. Tender:
   A tender is an auxiliary vessel that is used solely for or as a means of transportation between a pleasure craft and the shore. Safety equipment required onboard are:
   1. 2 paddles or oars fitted with rowlocks;
   2. one bailer with lanyard.

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Note 1:

Expiry dates must be adhered to for the following equipment to be considered serviceable:

• Red hand held flares

• Orange smoke signals
• Fire extinguishers
• EPIRBS (Emergency Position Indicating Radio Beacon)

Note 2:

Lifejackets, buoyancy vests and personal flotation devices have been approved for use as follows:

For operations within sheltered waters (Gazetted List of Sheltered waters):

• PFD 1 – Conforming with Australian Standard AS1512; or

• PFD 2 – Conforming with Australian Standard AS1499; or
• PFD 3 – Conforming with Australian Standard AS2260; or
• Lifejackets conforming with ‘Solas’ or ‘Coastal’ standards.

For operations outside sheltered waters:

• PFD 1 – Conforming with Australian Standard AS1512; or

• Lifejackets conforming with ‘Solas’ or ‘Coastal’ standards.

Minimum safety standards for pleasure craft or tender

A person shall not operate a pleasure craft or tender at sea unless it is:

1. Serviceable;

2. Seaworthy for the purposes for which it is operated;
3. Not overloaded;
4. Provided with a means or carries equipment which will enable a person who has fallen into the sea from the pleasure craft or tender to reboard it; and
5. Carries the prescribed safety equipment.

The above standards do not apply to a person on or in:

1. A surf ski, racing shell, canoe, kayak or windsurfer;

2. A sailing boat under 5 metres or with permanently closed hulls or a personal water craft, where persons on or in the boat or craft are wearing approved personal flotation devices (see Note 2); and
3. A pleasure craft which has been entered into a race in the event known as the Beer Can Regatta, or other approved aquatic events.

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Exempt areas

Safety equipment required for the exempt areas detailed below are:

1. Anchor and cable.

2. Waterproof torch.
3. Two paddles or oars fitted with rowlocks.

Approved exempt areas

1. Liverpool River – upstream from the north tip of Bat Island.

2. McArthur River – exempt area upstream from the south-west tip of Kangaroo Island.
3. South Alligator River – upstream from Manmalary Crossing.
4. Roper River – upstream from south point Green Island.
5. Adelaide River – upstream from Castle Point.
6. Victoria River – upstream from the junction of Baines River and Victoria River.
7. East Alligator River – upstream from Turkey Dreaming.
8. Daly River – upstream from Cleanskin Swamp.
9. King River.
10. Buffalo Creek.
11. Meckitts Creek.
12. Leeders Creek.
13. Saltwater Arm.
14. Howard River.
15. Sampan Creek – upstream from the old Barramundi Closure Line located through the point 131 47’06” East, 12 21’04” South.

Water skiers

A water skier must wear an approved personal flotation device.

• Penalty: 5 penalty units

Ski Observer

1. Apart from the operator of the water craft for skiing there must be a seperate person in the craft responsible, as an observer, watching and relaying signals to driver while the skier is in the water.
2. A water skier must not permit himself or herself to be towed unless an observer, as well as the driver, in in attendance.

• Penalty 10 penalty units

Personal water craft (jet ski etc)

The owner of a personal water craft must not use the craft or permit the craft to be used unless it is connected to a hand lanyard and the lanyard is securely attached to the operator.

• Penalty for no hand lanyard - any person 20 penalty units
• Penalty for no hand lanyard - business 100 penalty units

A person must not operate a personal watercraft unless it is fitted with an automatic engine cut out that is connected to a hand lanyard, which is securely attached to the operator.

• Penalty for the hand lanyard not secured to the operator - 20 penalty units

'Automatic engine cut out' means a device designed to stop the motor should the operator fall of the personal water craft.

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Small Craft

Reckless navigation

"A person must not navigate or use a small craft carelessly, negligently, recklessly or at a speed or in a manner that is dangerous to or likely to cause injury to a person or damage to property (including small craft).

• Penalty: 50 penalty units

Divers

1. A rigid replica of the International Code Flat 'A' measuing not less than 100 centimetres by 100 centimetres must be clearly visable from all angles and show at all times when a diver is operating from a vessel.
2. There must always be a person on proper watch on the vessel while the driver is in the water.
3. If a diver is not operating from a vessell they must tow a rigid replica of the diving sign International Code.
4. Flag 'A' measuring not less than 25 centimetres by 25 centimetres denoting a diver is operating in the area.

• Penalty: 20 penalty units

Restricted Areas

A person must not navigate a small craft:

1. At a speed exceeding 5 nautical miles per hour within 30 metres of a person bathing.
2. At a speed exceeding 5 nautical miles per hour within 150 metres of the waters edge at:
   • Nightcliff Beach
   • Fannie Bay Beach
   • Mindil Beach
3. At a speed exceeding 5 nautical miles per hour:
   • Through or in a mooring area
   • Within 30 metres of a moored vessel
   • Within 100 metres of a jetty, wharf or commercial shipping and cargo area.
4. At a speed that the was endangers the safety of a person, boat or structure.

• Penalty: 10 penalty units

Anchoring

The Master or other person in charge of a small craft must not anchor or permit the craft to be anchored:

• In a shipping chanel except in an emergency.
• In a declared pilotage area outside the Port of Darwin except in an emergency. (Melville Bay - Gove and Millner Bay - Groote Eylandt are declared pilotage areas).
• Near or at the approach to a wharf or jetty in a position that obstructs other vessels from entering or exiting.
• Within 100 metres of a water ski jump.
• In a position that obstructs the passage of another vessel.

• Penalty: 20 penalty units

For anchoring restrictions within the Port of Darwin please refer to the Port By-Laws - Contact Darwin Port Corporation.

Please note that large vessels may be restricted in their ability to manoeuvre or constrained by their draught and can not always give way to small vessels. These large vessels may not also have a blind sector and, therefore, may not use canoes, small boats etc. Small vessels must keep clear of vessels that are maneouvering, or departing a berth. Vessels must keep well clear of vessels that are flying a red flag, or showign an all round red light. Vessels must not secure to any navigational buoy.

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Safety checks for pleasure craft

Check your safety equipment and carry the required quantity. Ensure it is in good condition, of regulation standard and that it is stowed properly.

Know your basic “Rules of the Road” at sea, the International Signals for Distress and other basic signals. Refer to Courtesy for all Water Users, Navigation Lights (small vessels), Buoys, Beacons & Marks, Buoys, Beacons & Marks – MAP, Distress signals and Avoiding Collisions.

Tell someone where you are going. Before departing, advise a relative or responsible friend of your proposed itinerary and expected time of return and also give them a description of your boat and tell them who is travelling with you.

Check the weather. If in doubt don’t go out. Contact the Bureau of Meteorology for information.

Before departing check your boat and motor(s) and ensure they are in sound working order and drain plugs are tightly inserted. Always carry spares.

Check your fuel. Ensure you have enough for the trip with an adequate reserve for an emergency. Make sure your fuel lines and tanks are in good condition and that they don’t leak. It is advisable to always use fresh fuel and keep in an airtight container.

Carry a chart of the area, study it and familiarise yourself with positions of the navigational aids and hazards you are likely to encounter.

Don’t overload your boat. Distribute weight evenly and use the suppliers’ recommendations as to the maximum carrying capacity of your vessel.

Carry appropriate tools and spares in case of breakdown:

• Spark plug and spark plug spanners.

• Spare propeller.
• Penetrating fluid.
• Spanners, screwdriver, pliers etc.

Keep a good lookout at all times. Proceed with caution in unfamiliar waters.

Excess alcohol and boating don’t mix. The person in charge of the vessel is responsible for the safety of the craft and the lives of passengers.

Check that your navigation lights are working.

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Flotation in boats

Fitting of a "Builders Plate" to all recreational boats by mid-2005 built or imported for use is now agreed to by all state and territory marine authorities and industry.

There are two types of builders plate, one for boats less than 6 metres and for boats 6 metres or more in length.

For boats less than 6 metres, the type of flotation must be stated on the builders plate as:

• Level Flotation or
• Basic Flotation or
• Inadequate Flotation.

For boats less than 6 metres, from 1 July 2006, will become mandatory for builders to ensure at least "basic flotation" is installed.

In a real situation, the boat with level flotation is able to keep the person in the boat whilst waiting for rescue, this is an added advantage in waters that may be cold, or have numerous predators like crocodiles, sharks, stingers etc.

Basic or inadequate flotation can leave you hanging on to an upturned hull or the bow just above the water, or leave you swimming with no vessel in sight and only the small objects that may float from your boat.

It is therefore a better situation for rescue if you can remain in your boat and be seen more easily.

Information is available from Marine Safety Branch to test the boats at the flotation tank to see for yourself the results of flooding with the 3 types of flotation.

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Northern Territory Police Marine & Fisheries Enforcement Unit

Marine and Fisheries Enforcement Unit’s objectives are:

1. To reduce the incidence and impact of illegal fishing on the fish stocks in the Northern Territory by policing both amateur and commercial fishers;
2. To ensure the safety of all on our waterways and the safe and orderly operation of all watercraft within the Northern Territory; and to
3. Provide an efficient and effective marine search and rescue capability.

Ignorance is no excuse

We need your support, your eyes and ears for the continued protection of fish stocks in Northern Territory waters so that our children can fish in the future.

Any information will be treated confidentially.

For reporting fisheries offences, contact FISHWATCH, Free call 1800 891 136.

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Recreation boating courses

For the availabililty of training and courses appropriate for the operation of small recreational powercraft in the Northern Territory please contact the Marine Safety Branch.

Basic navigation course

Both the Casuarina Senior College (phone: 8920 1200) and Charles Darwin University (phone: 8941 4186) conduct basic navigation courses that are suitable for operators of pleasure craft.

AYF yachtmaster courses/examinations

The Winter School of Sailing conducts courses and examinations for crew of sailing vessels from the Darwin Sailing Club. Correspondence courses are also available. For further details phone 8981 9368.

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Anchors and anchoring

Most people know what the anchor is and if you throw it over the side (with rope attached) it will anchor your boat in good conditions. However, if conditions deteriorate, a dragging anchor can be dangerous.

1. There should always be a good length of chain, a minimum of 3 metres between the anchor and the anchor line. The purpose of the chain is to keep the stock or shank of the anchor parallel to the seabed which then allows the flukes of the anchor to gain maximum penetration into the seabed. The chain also helps prevent the anchor line chafing on the bottom.

2. Anchor lines are important. Don’t use an anchor line that floats such as polypropylene. It doesn’t help the anchor to dig in and hold and is prone to being cut off by other boats’ propellers.

   Nylon and silver rope are both suitable materials for anchor lines. Nylon is best for strength and stretching ability and is also more resistant to abrasion. Silver rope has less tensile strength.

   The length of anchor line is essential in order to hold a vessel in all conditions. To calculate how much line to let out (called the scope) allow for a ratio of 3 to 1. If you’re in 5 metres of water, let out 15 metres of line and if conditions are extreme increase the ration to 5 to 1.

   The scope is important as the more line there is out between the boat and the anchor, the flatter the pull is on the anchor, allowing it to dig firmly in. A short scope lifts the chain and stock of the anchor and eventually the flukes will break out.

3. Always lay your anchor out. Let it touch bottom and let the boat drift away until sufficient line is out.

   Don’t pick up a bundle of anchor chain and line and throw it over hoping it will untangle.

4. Don’t be tempted to anchor by the stern. Anchoring by the stern causes the stern of the vessel to sit lower in the water. Any wave actions or even the wash of other vessels can cause water to flow over the stern. Always anchor by the bow.

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Common types of anchors

	CQR or plough Can be used in small craft, however more suitable for larger heavier vessels. Both the Danforth and CQR or Plough anchors have good holding power in sand and mud but should not be used on reefs.
	Danforth This type of anchor is most commonly used by small craft and is recommended also for sand and mud. Reef should be avoided as the flukes may wedge in between rocks causing the retrieval of the anchor difficult.
	Reef anchors Reef anchors are designed to hold onto coral or rocks. Other types of anchors will lodge under coral and that’s where they will remain. The prongs on a reef anchor are meant to straighten out when excessive load is applied and can then be bent back into position and you create less damage to the coral.
	Sea anchor If you plan to go boating offshore or on an extended trip, a sea anchor is a valuable piece of equipment. Sea anchors when set will slow your drift and keep the bow of your vessel into the wind and waves. This is essential and also provides more comfortable conditions when drifting in choppy seas.

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Signals

	International flag “A” A rigid replica of a blue and white flag, the international flag, “A” exhibited by any craft or on a float indicates a diver is down – Keep Clear.
	International flag “B” The international flag “B” exhibited by any vessel indicates that dangerous cargo is carried. Keep well clear of these vessels at all times. Unless an emergency exists, do not use or display any signal which may be mistaken for distress. Regulations are made to protect your safety and pleasure.
	International flag “H” This flag indicates that there is a pilot on board the vessel. Within the Port of Darwin, any vessel less than 25 metres in length must give way to a vessel displaying this flag. (Refer to the Darwin Port Corporation Port By-laws)

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Marine emergency procedures

The safety equipment regulations are designed to make it easier for you to handle any emergency situation which might arise.

Below are a number of basic steps, which will help you to cope in such a situation. Emergencies are something we cannot foresee but with a little bit of common sense risks can be reduced.

1. Do not panic, remain as calm as possible.

2. Hand out lifejackets or safety vests and wear according to directions.
3. Attract attention from any passing vessel or persons on land, if close by, either by waving or by using a to or flare if the situation becomes desperate.
4. Check to make sure there is no danger of fire or explosion.
5. If hull is holed, block entry with any suitable material that will slow down the entry of water.
6. If you have ‘V’ distress sheets, place on top of vessel and secure properly.
7. If you have VHF radio. Refer to Marine Communications for Pleasure Craft.
8. If you have an EPIRB. Refer to EPIRB's - Safety via Satellite.

Reporting of accidents

If you have an accident, the NT Marine Act requires that the person in charge of a vessel shall report any accident to the Marine Safety Branch, Department of Planning and Infrastructure as soon as practicable.

This information is vital to help plan future safety education programs and the amendment of legislation. Your co-operation will assist others in the future.

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Distress signals

The following signals indicate distress and need of assistance. Use of the signals except for the purpose indicated is prohibited.

1.  Rockets or shells, throwing red stars fired one at a time at short intervals.
   
   
2. 1. Radiotelegraphy or any other signalling method consisting of...
      
      
   2. Radiotelegraphy consisting of the spoken word...
      
      
3. Square flag having above or below it a ball or anything resembling a ball.
   
   
4. Rocket parachute flare or a hand held flare showing a red light.
   
   
5. Smoke signal giving off orange coloured smoke.
   
   
6. Slowly and repeatedly raising and lowering arms outstretched to each side.
   
   
7. 1. Rectangle of international orange material with either a black letter V, a black square or a black circle upon it.
      
      
   2. A dye maker.
8. 1. A gun or other explosive signal fired at intervals of about a minute.
   2. Continuous sound with a fog signalling apparatus.
   3. Flames on a vessel from burning tar barrel, oil barrel.

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EPIRBs – Safety via satellite

How the system works

All pleasure craft in the Northern Territory operating beyond sheltered waters and more than 2 nautical miles offshore are required to carry an EPIRB.

Once activated, an EPIRB (121.5 or 406 MHz) transmits a distress signal on the international aviation distress frequency of 121.5MHz or the COSPAS-SARSAT frequency of 406MHz. These radio frequencies are constantly monitored by a series of earth-orbiting satellites which form part of an international search and rescue system known as COSPAS-SARSAT. As these satellites orbit the earth, they constantly “listen” for any activated EPIRBs.

If a satellite detects an activated EPIRB, it relays the EPIRB’s distress signal to satellite receiving stations (known as Local User Terminals, or “LUTs”) located in Albany, Bundaberg and Wellington NZ. Once the satellite has passed overhead, computers in the receiving stations analyse the EPIRB’s signal and calculate its position. An EPIRB location can generally be calculated to within radius of about 20 kilometres for a 121.5 MHz beacon and about 5 kilometres for a 406 MHz beacon.

The processed information from the satellite receiving stations is then automatically relayed by landline to Australia’s Rescue Coordination Centre (RCC), part of the Australian Maritime Safety Authority, in Canberra. Here, further computerised verification checks are performed and details of the EPIRB’s position confirmed. Depending on the circumstances of the emergency, a search and rescue operation is either coordinated by the RCC or details passed on to the Northern Territory Police to coordinate a rescue. Specially equipped aircraft and/or rescue boats are then used to home in on the EPIRB signal and effect a rescue.

Note: The 121 MHz EPIRB system will be discontinued in 2009.

406MHz

Currently, many craft carry the more advanced 406MHz beacon, which can indicate your position to within 5 kilometres, and can relay much more information than simply the distress location (for example, a 406MHz beacon can be programmed to tell the RCC the registration of the aircraft or ship, which in turn can indicate the type of craft, survival gear carried and the number of people on board).

Carry an EPIRB – it could save your life!

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Further information on search and rescue can be obtained from:

AusSAR Policy
GPO Box 2181
Canberra ACT 2601
Internet: www.amsa.gov.au

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Flares

Flares are required to be carried in vessels operating in the sea. In case of trouble, these can be your only means of indicating assistance is required. They are also essential for indicating your location to a search vessel.

Only fire a flare in an emergency (Check the instructions before use)

Flares should always be stored in a waterproof container, and in speedboats, endeavour to store them where they don’t receive too much pounding in rough conditions. Always replace them before the expiry date, for out of date flares can be unreliable. If you don’t know how to use them, familiarise yourself with their operation, keeping in mind that you can’t let one off just to see how it works.

Note: Flares can cause injury if misused. Keep them in a dry sealed container.

Types of flares

Parachute (rocket flare – red) Capable of reaching a height of 300m and can be seen for up to 40km at night and 15km by day.
	Operation A Remove caps at each end.
	Operation B Remove safety pin and lever will drop down.
	Operation C To fire, hold flare vertically and press firing lever against rocket cylinder.
Red hand flare – Can be seen up to 10km away, on a clear night.
	Operation A Remove caps both ends – bottom cap is a striker. Hold flare at base and use striker to ignite flare at top end.
	Operation B Once flare is ignited – hold away from you and as high as possible until finished.
Orange smoke flare - Visible up to 4km away. Daytime use only.
	Operation A Same as the red hand flare.

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Avoiding collisions

Excerpt from International Regulations for Preventing Collisions at Sea

Steering and sailing rules

Lookout

Every vessel shall at all times maintain a proper look out by sight and hearing as well as by all available means appropriate in the prevailing circumstances and conditions so as to make a full appraisal of the situation and of the risk of collision.

Safe speed

Every vessel shall, at all times, proceed at a safe speed so that she can take proper and effective action can be taken to avoid collision and the vessel can be stopped within a distance appropriate to the prevailing circumstances and conditions.

Risk of collision

Every vessel shall use all available means appropriate to the prevailing circumstances and conditions to determine if risk of collision exists. If there is any doubt such risk shall be deemed to exist.

Narrow channels

A vessel proceeding along the course of a narrow channel or fairway, shall keep as near to the outer limit of the channel or fairway which lies, on her starboard side as is safe and practicable.

Action to avoid collisions

1. Any action taken to avoid collision shall, if the circumstances of the case admit, be positive, made in ample time and with due regard to the observance of good seamanship.

2. Any alteration of course and/or speed to avoid collision shall, if the circumstances of the case admit, be large enough to be readily apparent to another vessel observing visually or by radar; a succession of small alterations of course and/or speed should be avoided.
3. If there is sufficient sea room, alteration of course alone may be the most effective action to avoid a close-quarters situation provided that it is made in good time, is substantial and does not result in another close-quarters situation.
4. Action taken to avoid collision with another vessel shall be such as to result in passing at a safe distance. The effectiveness of the action shall be carefully checked until the other vessel is finally passed and clear.
5. If necessary to avoid collision or allow more time to assess the situation, a vessel shall slacken her speed or take all way of stopping or reversing hers means of propulsion.

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Courtesy for all water users

The Collision Regulations apply to all vessels upon the high seas and all waters connected therewith, navigable by seagoing vessels. There are numerous small billabongs and other enclosed waters in the NT to which regulations do not strictly apply. In the interests of courtesy and safety, boat users are asked to observe the following rules:

 

	When two powerboats are approaching head on, or nearly head on, each must alter course to starboard and pass each other’s port side.
	When overtaking another vessel. The vessel being passed has right of way and you must always keep clear of that vessel.
	When a vessel is crossing your bow from starboard to port that vessel has right of way and you should keep clear. Stop or reduce speed and pass under his stern, give way to the vessel on your right.
	When in a narrow channel keep to starboard.
Vessels proceeding after dark on inland waters should have navigational lights fitted or carry a torch to signal their presence to other vessels as appropriate.
Vessels operating in billabongs and other enclosed waterways should proceed at a speed, which does not inconvenience or endanger other vessels.

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Navigation lights (small vessels)

Some light on the subject

Navigating at night requires special care and attention. Vessels operating from sunset to sunrise, whether at anchor or underway, must carry and exhibit the correct lights. A vessel is underway when not anchored, moored to the shore or ground. Navigation lights must also be displayed during daylight hours in periods of restricted visibility. This guide will assist you to understand the correct navigation lights of your boat.

Range of visibility of lights

1. Vessels of 12 metres or more in length but less than 20 metres:–

   • Masthead light – 3 miles.
   • Sidelight, stern light and white, red or green all round light – 2 miles.
2. Vessels of less than 12 metres in length:–
   • Masthead light – 2 miles.
   • Sidelight – 1 mile.
   • Stern light – 2 miles.
   • White, red or green – all round lights – 2 miles.

Boating Terminology

Arc of visibility of lights

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Power craft underway

Power craft of less than 7 metres in length with a maximum speed not exceeding 7 knots shall exhibit a white light visible all round and, if possible, separate or combined sidelights.
Separate side lights where practicable	Combined side lights where practicable
Power craft of less than 12 metres in length shall exhibit a white light visible all round and separate or combined sidelights. Masthead or white all round light shall be carried at least one metre above the sidelights.
Separate side lights	Combined side lights
or...a masthead light, combined side light and stern light	or...a masthead light, separate side light and stern light
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Power craft more than 12 metres in length but less than 20 metres in length shall exhibit a masthead light separate sidelights and stern light. The masthead light shall be at least 2.5 metres above the gunwale.
Separate side lights	Separate side lights
Or A masthead light combined sidelights and stern light. Combined sidelights shall be carried at least one metre below the masthead light.	Combined side lights

Sailing vessels underway

Sailing vessels of less than 7 metres in length, or vessels being rowed shall, if practicable, exhibit the light required for sailing vessels over 7 metres in length. If not, they shall have ready for use an electric torch or lighted lantern showing a white light which shall be exhibited in sufficient time to prevent a collision.
Torch or lantern	Torch or lantern
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Sailing vessels of more than 7 metres in length and not more than 20 metres in length shall exhibit a combined lantern, at or near the top of the mast incorporating sidelights and stern light, or separate sidelights and stern light.
Combined lantern	Combined lantern
Combined lantern	A sailing vessel of any length, which is fitted with sidelights and a stern light (but not a combined lantern) may, in addition, carry two all round lights in a vertical line at or near the top of the mast. The upper light shall be red and lower green.
Sailing vessels more than 20 metres in length shall exhibit sidelights and stern light and may carry the optional red and green all round lights described in 5C. They may not carry a combined lantern.
Sailing vessels while underway (being motor driven) shall exhibit navigation lights applicable to powerdriven vessels.
Navigation lights

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Power craft/sailing vessels at anchor

Vessels less than 50 metres in length at anchor shall exhibit an all round white light placed where it may be seen.
All round white light	All round white light
All round white light

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Buoys, beacons and marks

It is essential that pleasure craft operators have a sound knowledge of navigational aids. A thorough understanding of Buoyage System “A” is important. Please study the following section carefully and help make our Northern Territory waterways safer.

Buoyage system “A”

Many countries throughout the world have agreed to the use of a uniform system of navigational marks known as Buoyage System “A”. The system, developed with the assistance of the International Association of Lighthouse Authorities (IALA), has been in use throughout Northern Territory waters since late 1983. Buoyage System “A” provides a better organised and safer way of coding our navigational marks.

Types of marks

1. Lateral indicates port and starboard hand sides of channels.

2. Cardinal mark indicates that deeper water lies to the direction shown to the North, South, East and West.
3. Isolated danger indicates isolated dangers of limited extent with navigable water all around them – but don’t pass too close.
4. Safe water indicates that there is navigable water all around and under that position eg. mid channel buoy.
5. Special indicates special features eg. spoil grounds or prohibited anchorage.

	Entering port Upon entering a port the port hand mark (red) should be passed on your vessel’s port side.
	Leaving port Alternatively, when departing a port the port hand buoy (red) should be passed on your vessel’s starboard side.

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Lateral marks

Lateral marks are usually positioned to define well-established channels and indicate port and starboard hand limits of the navigation route into a port.

	Direction of buoyage – where there may be any doubt, the direction of buoyage can be indicated on charts by this symbol.
	Port mark – is coloured red and the basic shape is a can; By night a port buoy shows a red light.
	Starboard mark – is coloured green and the basic shape is conical; by night a starboard buoy shows a green light.

Isolated danger mark

The isolated danger mark designates an isolated danger of limited extent, which has navigable water all round it eg. an isolated shoal, rock or wreck.

Topmark – Two black spheres positioned vertically and clearly separated. Colour – Black with one or more red horizontal bands. Light – A white flashing light showing a group of two flashes. The characteristics may be best remembered by association of two flashes with two spheres as the topmarks.

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Safe water marks

Safe water marks indicate that there is navigable water all round the mark, eg mid channel to land fall buoy.

Topmark – A single red sphere. Colour – Red and white vertical stripes. Light – Exhibits a white light, isophase, occulting, or single long flash and a single sphere association may help in remembering these characteristics.

Cardinal marks

A cardinal mark indicates where the safest water may be found and is used in conjunction with the compass.

Uses – A cardinal mark may indicate the deepest water in the area, the safe side on which to pass a danger or draw attention to a feature in a channel such as a bend, junction or an end of a shoal.

Top marks – Black double cones clearly separated.

Name of marks – The mariner is safe passing:

• North of the North mark.

• East of the East mark.
• South of the South mark.
• West of the West mark.

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Colours – Black and yellow horizontal bands with position of the band indicating the respective cardinal points.

• North – Topmark point up, black band above yellow band indicating the respective cardinal points.
• East – Topmark points outward, black bands above and below yellow band.
• South – Topmark points down, black band below yellow band.
• West – Topmark points inward, black band between yellow bands.

Lights

A cardinal mark exhibits a white light and its quadrant is distinguished by a specific group of quick or very quick flashes:

The frequencies of the flashes are:

• North – Uninterrupted flash.
• East – 3 flashes in a group.
• South – 6 flashes in a group followed by a long flash.
• West – 9 flashes in a group.

To aid memory, associate the number of flashes of each group with that of a clock face, three o’clock East, nine o’clock West.

To ensure that no confusion occurs between East, South and West marks a long flash immediately follows the 6 flashes of the South mark.

Note: It is not normal to find cardinal marks or lights in small craft channels.

Special marks

Special marks indicate a special area of feature such as:

• Trafic separation.
• Spoil ground marks.
• Cable or pipe line marks including outfall pipes.

Also to define a channel within a channel eg. a channel for deep draught vessels in a wide estuary where the limits of the channel for normal navigation are marked by red and green lateral buoys.

Topmark – Where topmark is carried it takes the form of a single yellow x.

Colour – Yellow.

Light – If it is yellow, the rhythm may be any other than those used for the white light of cardinal, isolated danger and safe watermarks.

Variations in the design of buoys will exist in many areas. The illustrations indicate the approved shapes, colourings and topmark.

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Buoys, beacons and marks map

At a glance:

• (1) Lateral mark
• (2) Safe water mark
• (3) Isolated danger mark
• (4) Cardinal mark
• (5) Special mark.

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Fire prevention and safety afloat

Fire prevention can be effectively achieved through good housekeeping. Even though it is essential you know how to fight a fire and have the correct equipment on board, never having to fight fire is a far better course of action.

Fire at sea does not discriminate.

Any fire on a boat, especially fires involving flammable fuel, can be a terrifying experience with the potential to cause serious burns or death.

It is a fact that petrol and oil fires aboard small vessels spread rapidly generate intense heat and usually overwhelm those on board. In many cases they are either blown or jump overboard. Few people are able to successfully fight a fire aboard a small vessel.

The answer to the problem lies in preventing fires rather than fighting them.

A great number of fires or explosions occur immediately after boats have been refuelled. By using common sense and taking proper precautions, boating fires can be prevented.

• Have the correct fire extinguishers in your boat, know how to use them, maintain them and locate them in accessible areas.
• Keep the bilge and engine room clean and free of rags, newspapers and other combustible materials.
• Regularly check that engine rooms are properly ventilated.
• Use only appliances such as stoves and heaters that are approved for marine use.
• Never use cigarette lighters or matches while searching in lockers, use a battery powered torch.
• Check fuel systems at regular intervals for leaks and spillage.
• Any spare petrol should be carried in approved containers.
• Check the electrical system for faults regularly and keep all components as clean as possible.

Some common causes of fire aboard small craft

• Engine backfiring in air laden with combustible vapour.
• Hot exhaust pipe igniting adjacent combustible materials.
• Spontaneous combustion of oil rags in badly ventilated compartments.
• A spark caused by static electricity during refuelling.
• Short-circuiting and overloading of the electrical system.
• Smoking in bed.

Remember, to avoid potential fire hazards – all fuel systems, electrical systems and LP Gas systems should be correctly designed, installed and maintained by qualified persons.

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Refuelling your boat

• Turn off all engines, motors, fans, heating devices, electrical equipment and LP Gas appliances before fuelling.
• Take care when refuelling! Don’t smoke or allow naked flames on or in the vicinity of your vessel while fuelling. Fuel spilled, either accidentally or from overflowing the fuel tanks, produces vapours which can enter the bilge and may be ignited by a spark – often from the boat’s electrical system.
• Have a filled fire extinguisher handy.
• Wipe up all spills.
• Leave room in tanks for fuel expansion.
• Check bilges for leakage and fuel odours, ventilate until fuel odour is gone, before starting engines.
• Never refill portable fuel tanks in the boat; take them ashore for filling and wipe off any spillage before replacing them aboard.
• Fuel related fires could also start when a boat is cruising. These fires generally result when some component of the fuel system starts to leak and vapours trapped in the vessel’s bilge are ignited. Regularly inspect and maintain fuel systems and avoid using temporary or “stop gap” solutions to fix leaks.

Electrical installation

• Frequent, fires and explosions aboard small vessels are caused by short circuits or overloading. To ensure protection from these hazards, have all electrical installation and maintenance carried out by a qualified marine electrician.
• Never undertake temporary repairs using makeshift materials, except in an emergency.
• Never use multiple adaptors for connecting appliances a circuit not initially designed for this purpose.
• Never replace an existing fuse with a larger one.
• Never overcharge batteries as these release excessive amounts of the explosive gas hydrogen into the air.
• Ensure battery spaces are well ventilated.

LP Gas

• Ensure all LP Gas installations are carried out and serviced by a licensed gas fitter.
• Regularly check permanent venitlators, flues and vents to ensure that they are clear.
• Leakages can lead to suffocation or explosions.
• Remember LP Gas is heavier than air. Any leaked gas will always flow downards, collect in low places and will be slow to dissapate without ample venitalation and movement of air.
• Always turn off gas at the bottle.
• Never use a naked flame to check for leaks.

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Marine pollution

The Northern Territory Marine Pollution Act and Marine Pollution Regulations are expected to commence in October 2002. The legislation aims to protect the marine and coastal environment by minimising discharges of shipsourced pollutants into coastal waters.

Below is a summary of applicable rules to owners and users of all vessels.

Oil

A vessel’s owner and a vessel’s master/operator must ensure that oil is not discharged from the ship into the sea.

Oil means petroleum of any form and includes:

1. Any liquid hydrocarbon mixture occurring naturally in the earth;

2. Sludge or oil refuse;
3. Any oil used in connection with the propulsion and auxiliary machinery of the vessel; and
4. A mixture with any oil content.

Garbage

Garbage means all kinds of victual, domestic and operational waste, including plastics, generated during the normal operations of the vessel and liable to be disposed of including plastics. It does not include fresh fish and parts of fresh fish or the release of small amounts of food wastes for the specific purpose of fish feeding.

The garbage rules change depending how far the vessel is off the coast: eg.

Within 3 nautical miles of the coast

A vessel’s owner and a vessel’s master/operator must ensure that no garbage is discharged from the ship into the sea.

At a distance 3 to 12 nautical miles off the coast

Garbage that is food waste, paper products, rags, glass, metal and bottles may be disposed of if it is comminuted or ground so that it is capable of passing through a screen with openings no greater that 25mm.

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Transfer operations

A vessel’s owner and a vessel’s master must ensure that a pollutant is not discharged from the vessel into the sea during a transfer operation.

A pollutant means any substance, which if introduced into the sea is liable to create hazards to human health, to harm living resources and marine life, to damage amenities or to interfere with other legitimate uses of the sea. It includes garbage, noxious liquid substances, packaged harmful substances, oil and sewage.

At no time can plastics be discharged into the sea.

A transfer operation means any operation involved in preparing for, starting, carrying on, or finishing, a transfer of a pollutant including ‘ship to ship’, ‘ship to shore’ and ‘ shore to ship’.

Night transfer operations must have a permit issued by the Marine Safety Branch, Department of Planning and Infrastructure.

A vessel that is more than 12 metres in length
must ensure that a placard is displayed setting out
garbage disposal requirements.

Reporting incidents

A vessel’s master or operator must notify of a pollution incident without delay. This can be done by calling the following number 1800 064 567.

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Marine communications for pleasure craft

There are only a few pieces of safety communications equipment that a pleasure craft must carry when operating at sea within the Northern Territory, these are:

• 2 orange smoke flares and two red flares;

• If the vessel is over five metres a V-Sheet; and
• If the vessel is more than two nautical miles from the coastline an EPIRB.

There are however many pieces of additional equipment a pleasure craft may choose to carry. There can be no better reason for installing a marine radio in your boat other than one day it may save a life. That life could be yours or of a member of your family.

The sea can be a frightening and lonely place, especially if you are in trouble. A marine radio gives you the ability to advise other people that you need help. It may be your only contact with the outside world.

Marine communication systems

There are two main marine safety communication systems operating in Australia. AMSA’s Safety Off Shore System and the State and NT Government’s Coast Radio Australia System.

Safety offshore system

This system is based on GMDSS (Global Maritime Distress and Safety System) principles which are part of the SOLAS Convention (Safety Of Life At Sea) which focuses on large vessels.

There are two equipment types used; these are HFDSC (Digital Selective Calling) and Sat-C satellite communications. Pleasure craft operating in remote areas or participating in extended voyages such as cruising yachts may choose to use this equipment.

This system is managed and monitored at the Rescue Coordination Centre (RCC) in Canberra. There are two HF radio stations used to operate this system one at Wiluna (VMW) in Western Australia and Charleville (VMC) in Queensland.

Further Information can be gained from http://www.amsa.gov.au/Search%5Fand%5FRescue/

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Coast radio Australia network

This system consists of nine stations located around Australia, with one radio in each state except Queensland and Western Australia which have two. They are all monitored by local people who are able to communicate with local authorities and each other.

Coast radio Australia network

NT marine communications

Coast Radio Darwin VKD 999

Coast Radio Darwin monitors CH16 VHF, 4125, 6215 and 8291 kHz HF frequencies for distress, urgency and safety calls.

All times are CST.

Coast Radio Dariwn transmits weather and other Marine Safety Information as per the times and frequencies shown above.

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Radio operational procedures

In a boating emergency, unless correct radio procedures are followed, things can become chaotic. It is important that you know how to effectively call for help and also to recognise that another boat is calling for assistance.

Standard radio procedures have been laid down and are used by vessels of all nationalities. These are explained in detail in the Marine Radio Operators Handbook. This book is compiled by the Australian Maritime College and the Australian Communications Authority, a copy may be accessed from www.amcom.amc.edu.au/handbook.

The basic procedures are summarised below:

Distress call

To be used if in grave and imminent danger and you require immediate assistance. Example vessel sinking or on fire.

Mayday, Mayday, Mayday
This is [Name and call sign if you have one] (spoken three times)
Mayday
[Name and call sign if you have one]
Details of the vessel’s position
Nature of distress and assistance required
Other information including number of persons on board

It is recommended that you also activate your EPIRB in addition to making a Mayday call.

Urgency call

The urgency call is used when there is concern on the safety of your vessel or a person. Example medical emergency or a man overboard.

Pan Pan, Pan Pan, Pan Pan
Hello all stations, Hello all stations, Hello all stations
This is [Name and call sign if you have one] (spoken three times)
Details of the vessels position
Details of assistance required and other information

Safety call

The safety warning is used if you need to broadcast and important safety warning. Example a partly submerged object or an accidentally activated EPIRB.

Saycure-e-tay, Saycure-e-tay, Saycure-e-tay
Hello all stations, Hello all stations, Hello all stations
This is [Name and call sign if you have one] (spoken three times)
Details of the warning / announcement

VHF Distress, Urgency and Safety calls can be initiated on channel 16, they may be continued on channel 67.

HF Distress, Urgency and Safety calls can be initiated on 4125, 6215 and 8291, they may be continued on these channels or change to channels 2182, 12290 or 16420 if better reception is required.

Note: The nature of HF transmission may result in distress or safety calls being answered by any Australian coastal station.

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Weather

The Bureau of Meteorology is responsible for the broadcasting of weather on HF radio through a contract with TVNZ(A).

There are two sets of frequencies, one covering the East of Australia (VMC) the other the West (VMW), these are continually broadcasting on a four hour cycle which means weather for any one area is broadcast six times in any 24 hour period.

Other ways to access weather information

VHF broadcasts Weather is also broadcast over VHF channel 67 by Coast Radio Darwin at 0803 and 1803 each day. This consists of the forecast for Darwin Harbour and surrounding areas plus the Coastal Waters Forecast for Daly River to Cape Don.

Phone for weather There are various types of weather information that can be gained over the phone including:–

• 1900 955 367 – Coastal forecasts, warnings and observation bulletins.

• 1300 659 214 – Non cyclone warnings including coastal waters and wind warnings.
• 1300 659 211 – Tropical cyclone warnings and information.

(1300 numbers are equal to the cost of a local call; 1900 numbers have a cost per minute)

 

VMW VMC 2056 2201 4149 4426 6230 6507 8113 8176 12362 12365 16528 16546

Transmissions will be on four frequencies simultaneously
Blue are day time only (7am to 6pm)
Red are night time only (6pm to 7am)
Black are 24 hours a day

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Weather on the web

There is a wide range of weather available on the web which can be checked and printed before going on a day’s water outing including forecasts, warnings and observations. There is also a wide range of additional information on ways you access weather: http://www.bom.gov.au/marine.

For today’s weather warnings and forecasts go to www.bom.gov.au/weather/nt.

Other marine safety information

All marine safety information, excluding weather, is broken down into eight segments around Australia and given a letter from A through to H. These areas are known as the Auscoast Areas or Navarea X.

Marine safety information is broadcast at 57 minutes past the hour somewhere in Australia, see schedule below, on HF radio 8176 kHz. Each HF station broadcasts the warnings for its adjacent area plus the one either side. A Sat-C system instantly receives them as they are issued.

 

Station	Primary	Secondary	Area
Adelaide	0357 UTC	0757 UTC	D,E,F
Cairns	2357 UTC	1257 UTC	H,A,B
Darwin	0157 UTC	0957 UTC	G, H, A
Darwin	1127 (local)	1927 (local)	G, H, A
Gladstone	2257 UTC	1157 UTC	A, B, C
Hobart	0557 UTC	-	C, D, E
Melbourne	0257 UTC	2157 UTC	C, D, E
Perth	0657 UTC	1057 UTC	E, F, G
Port Headland	0457 UTC	0857 UTC	F, G, H
Sydney	0057 UTC	1357 UTC	B, C, D

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Marine communications equipment licensing

VHF

Individual ship licences are not required for VHF radios. Previously call signs used to be issued as part of the process of licensing VHF as this is no longer required, radios in a new installations and installations where the licence has expired will not have a call sign. A vessel in this situation is to use the name of the vessel to identify themselves.

Users are still required to hold an operators qualification. The qualification may be a Restricted Radiotelephone Operators Certificate of Proficiency, or a Third Class Commercial Operators Certificate of Proficiency, or a Marine Radio Operators Certificate of Proficiency, or a Marine Radio Operators VHF Certificate of Proficiency.

HF

HF radios must have an apparatus licence. More information on getting one of these licences can be found at www.acma.gov.au.

Users are required to hold an operator’s qualification. The qualification may be a Restricted Radiotelephone Operators Certificate of Proficiency, or a Third Class Commercial Operators Certificate of Proficiency, or a Marine Radio Operators Certificate of Proficiency.

Mobile phones and satellite phones

With the increased coverage of mobile and satellite phones they are becoming a common item carried on pleasure craft and provide excellent general communications between vessels and the shore however, they should not be seen as a substitute or replacement for emergency communications.

Some points to consider include:

• A mobile phone only allows for communication between two people at any one time which may necessitate messages being passed via a third party with a real risk that vital information may be lost or misinterpreted, causing a delay to the response. Few rescue vessels will be fitted with or carry cellular phones.
• The cellular system does not provide for distress priority alerting, consequently it is possible that calls may not be immediately connected if the system is very congested, such as in areas around major cities.
• Mobile phone range is very restricted and within the Territory it is easy to travel outside the range. In a case of an emergency the phone may not be in range.
• Rescue vessels cannot home in on a mobile or satellite phone signal. Use of recognised maritime communications equipment allows direction finding equipment to be used.
• Mobile and satellite phones are more prone to damage from water and have only limited battery capacity.
• If you do have a phone on board your vessel in the Northern Territory, you may contact the police/search and rescue on 8922 1586. This will be instantly recognised as a marine incident.

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Tidal information

Tidal notes

Tidal levels

In accordance with modern hydrographic practice, the official tidal predictions and Mean Tidal Planes in these tables are referred to the datum of Lowest Astronomical Tide.

Tidal heights

The height of the tide in metres and decimals is reckoned from the lowest astronomical tide. When a low water falls below datum, it is marked with a minus sign (-). When reading navigational charts, tidal heights should be added to chart depths unless preceded by a minus sign, when they should be subtracted.

Meteorological effects on tides

Meteorological conditions, which differ from the average, will cause corresponding differences between the predicted and the actual tide. Variations in tidal heights are mainly caused by strong or prolonged winds and by unusually high or low barometric pressure.

Tidal predictions are computed for average barometric pressure. Low pressure systems tend to raise sea levels and high pressure systems tend to lower them. The water level does not, however, adjust itself immediately to a change of pressure. It responds moreover to the average change in pressure over a considerable area.

The effect of wind on sea level and therefore, on tidal heights and times is variable and depends on the topography of the area in question. In general, it can be said that wind will raise the sea level in the direction towards which it is blowing.

A strong wind blowing straight onshore will “pile up” the water and cause high waters to be higher than predicted, while winds blowing off the land will have the reverse effect.

Where to get tidal information

Tide tables for the Northern Territory are available here or contact the Marine Safety Branch.

Tide diaries

Are available from various fishing tackle shops and boat chandlers. Please contact Darwin Port Corporation, Ph: 8922 0660.

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Tidal variations for various rivers

This information is provided purely as a guide. Details are compiled solely from local expertise and variations could differ considerably from actual times. In the interest of safety, river users are advised to make allowances for potential inaccuracies. View Tidal Variations for Various Rivers (pdf 78kb).

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Guide to tidal abbreviations

HAT: Highest Astronomical Tide
LAT: Lowest Astronomical Tide

These are the highest and lowest levels, which can be predicted to occur under average meteorological conditions and any combination of astronomical conditions. These levels will not be reached every year. HAT and LAT are not the extreme levels that can be reached, as storm surges may cause considerably higher and low levels to occur.

MHHW: Mean Higher High Water
MLLW: Mean Lower Low Water
MHLW: Mean High Low Water

The height of mean lower high water is the mean of the lower of the two daily highwater over a long period of time. When only one high water occurs on some days no value is printed in the MLHW column indicating that the tide is usually diurnal. Again the definition of Mean Lower High Water is similar.

MLHW: Mean Lower High Water
MHLW: Mean Higher Low Water

The height of mean lower high water is the mean of the lower of the two daily highwater over a long period of time. When only one high water occurs on some days no value is printed in the MLHW column indicating that the tide is usually diurnal. Again the definition of Mean Lower High Water is similar.

MHWS: Mean High Water Springs

Long term average of the heights of two successive highwater during those periods of 24 hours (approximately once a fortnight) when the range of tide is greatest, at full and new moon.

MLWS: Mean Low Water Springs

Is the long-term average value two excessive low waters over the same periods as defined for MHWS.

MHWN: Mean High Water Neaps

The average throughout a year of the heights of two successive highwaters when the range of tide is the least, at the time of first and last quarter of the moon.

MLWN: Mean Low Water Neaps

The long-term average value of two successive low waters over the same periods as defined for MHWN.

ML: Mean Sea – Level

The average levels of the sea over a long period (preferably 18.6 years) or the average level, which would exist in the absence of tides.

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AHD: Australian Height Datum

This datum has been adopted by the National Mapping Council as the datum to which all vertical control for mapping is to be referred.

Range:

The range of the tide is the difference between the height of “High Water” and the next succeeding or last proceeding “Low Water”.

Rise:

The rise of the tide is the height of high water above chart datum.

“King tides”:

A non-scientific term, but the popular concept is that it is the higher highwater.

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Guide to tidal planes

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A guide to recreational fishing in the NT

The Fisheries Group of the Department of Business, Industry and Resource Development has developed Management Plans to protect the Territory's barramundi, mud crab, jewfish, Spanish mackerel, golden snapper and other fish and aquatic resources from overfishing and to ensure they they can be shared amongst all fishermen.

The personal possession limits, as ammended 1 January 2002, for managed species are as follows;

• 5 barramundi NT wide except for the Mary River where a limit of 2 barramundi applies (NT wide minimum size limit is 55cm)
• 5 black jewfish
• 5 Spanish mackerel
• 5 golden snapper
• 10 mud crab - (with a boat limit of 30, if 3 or more people are on board, minimum size limit for males is 13cm, females 14cm)
• 10 tropical rock lobsters (with a boat limit of 30, ir 3 or more people are on board)
• bait fish (mullet, whiting, garfish, pilchards, and sardines)
• 10 litres of molluscs, with shells on

General personal fish possesion limit

A general possession limit of 30 fish also applies to each person and this includes the possession limits for the managed finfish species shown above (barramundi, black jewfish, Spanish mackerel and golden snapper).

Species exempt from possession limits are:

• Prawns
• Bait fish (mullet, whiting, garfish, pilchards, sardines and herrings)
• Marine bream
• Echinoderms (sea urchins and starfish)

The following controls also apply to assist with practical identification and enforcement:

• The entire skin must be left on fillets or trunks of non-managed fish species
• If a fillet is dissected in anyway, it will be deemed that each piece is a whole fillet and therefore equal to half a fish
• Fillets of barramundi, Spanish mackerel, golden snapper and black jewfish must be kept seperate from each other and from fillets or other species

For further advice telephone the Group's Fisheries Recreational Fishing Office on (08) 8999 2372.

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List of gazetted sheltered waters

(smooth and partially smooth waters)

As at 1 July 2004

Area

1. Dalywoi Bay.

2. All inland waters.
3. Bathurst Island – Port Hurd.
4. Bynoe Harbour.
5. Gove Harbour.
6. Port Bradshaw.
7. Port Essington.
8. Vanderlin Islands.
9. One (1) nautical mile seawards from the mean low watermark on the coast (including the coasts of islands).
10. Cobou