Draft Restrictions

The two tidally restricted and therefore controlling areas for traversing Torres Strait are Varzin Passage and The Prince of Wales Channel. Utilisation of daily tide rises enables the Service to pilot ships through these areas with a maximum static draft not exceeding 12.2 meters (40 feet).

Minimum under keel clearances required are as follows;

Draft		Varzin Passage	POW Channel
	11.9m or less	1.0m	1.0m
	over 11.9m	1.0m	10% of draft

The 12.2 metre draft limitation applies from Booby Island to Cairns in the Inner Route and from Booby Island to Dalrymple Island in the Great North East Channel. Vessels over 10m are advised of the safe 'tidal windows' after ordering the pilot.

TORRES STRAIT TIDE GAUGES

1

Transmitting tide gauges are located in the Torres Strait region as listed in the table below:

Name & Identification		Position	Hours of Operation
	Booby Island (BB)	10˚36’09”S  141˚54’36”E	H 24
	Goods Island (GD)	10˚33’53”S  142˚08’44”E	H 24
	Turtle Head (TH) Hammond Island	10˚31’14”S  142˚12’47”E	H 24
	Nardana (height) NT Nardana (stream) NS	10˚30’17”S  142˚14’38”E	H 24
	Ince Point (IP) (Wednesday Island)	10˚30’52”S  142˚18’17”	H 24

2

All stations broadcast on the one frequency, namely VHF Marine Channel 68 (156.425 MHz). The tide heights are broadcast in the following sequence:

	Booby Island
	Goods Island
	Turtle Head
	Ince Point

The tide height is preceded by the station identification, which is broadcast as morse code.

3

The tide height is transmitted as groups of pseudo morse 'dots', the number of dots in groups indicating respectively metres and tenths of metres of tide height above chart datum. A zero is indicated by a 'dash' and negative heights indicated by a preceding 1.5 second warbling tone.

4

The station identification and tide height broadcast is repeated during each cycle. A complete cycle of tide heights from all four tide gauges takes 150 seconds.

HAY POINT/DALRYMPLE BAY & ABBOT POINT

The maximum draft between Central Queensland Ports and Hydrographers, Palm, or Grafton Passages is limited only by the permissible draft at the loading port.