Four World War II mines have been discovered on the seabed
during a Navy exercise in Auckland's Hauraki Gulf this week.
Two were discovered during a routine Autonomous Underwater
Vehicle (AUV) operation conducted by the US Navy as part of
the international Mine Countermeasures Exercise hosted by the
Royal New Zealand Navy.
The discovery was confirmed by a New Zealand navy dive team.
Two more mines were discovered by a Royal Australian Navy AUV
team and later confirmed by Japan's dive team.
The four mines were originally laid as part of a controlled
defensive minefield in September 1942.
Seven loops totalling 16 mines were laid as part of a larger
defensive manoeuvre which saw 1391 friendly mines laid in 10
harbours across New Zealand.
At the end of the war most mines were disposed of using mine
sweepers, however some 50 sank to the bottom, irrecoverable
until new technology was available.
The Navy advises that due to their age and condition any
remaining World War II mines are unlikely to be dangerous.
However, they recommend caution if divers find one. It is
recommended that any discovery be reported to the
Harbourmaster or Royal New Zealand Navy.