Entry and exit is programmed around the strength of the tidal flow in the
entrance and takes place day and night. Berthing normally takes place 30
minutes after negotiating the harbour entrance. Tankers will be berthed where
practicable, starboard side alongside (bow out), to facilitate emergency
departure. The entrance approaches are dredged giving a minimum depth of 14.1
m. During northerly and easterly gales, breaking seas may be experienced in
this vicinity, particularly on an ebb tide. Inner harbour navigable channels
have been dredged to 12.9 m. The western channel is now closed to shipping.
Approach Routes - Tankers
The Maritime Safety Authority of New Zealand has published a
voluntary code for ships carrying oil or other harmful liquid substances in
bulk as defined in Annexes 1 and 11 of MARPOL 73/78.
Ships are to keep at least 5 nautical miles off land, any charted danger,
or any outlying island(s) until reaching the position where alteration is
required to make port. A greater distance off may be necessary in adverse
on-shore weather, or if it is known that the ship has any mechanical
deficiency that might impair either the motive power or manoeuvrability.
From the north -keep at least 4 nautical miles to the west of
Mayor Island and thence to the Pilot Station.
From the east - keep at least 5 nautical miles to the north of Volkner
Rocks, thence 3 nautical miles to the north of Astrolabe Reef and thence to
the Pilot Station.