Visitors at Taiaroa Heads. Photo by the Star.
Oil would wash up on the shore of Taiaroa Head four days
after a worst-case scenario deep-water spill off Otago,
according to a modelling report released today.
The report - commissioned by Greenpeace NZ - also shows that
in most scenarios oil would not make landfall on the Otago
coast, because sea currents and climatic conditions would
push the oil eastwards.
The report, embargoed until today, comes after oil and gas
exploration and production company Anadarko announced almost
two months ago it plans to drill a $US100 million test well
60km off the coast of Otago Peninsula, at the southern margin
of the Canterbury Basin.
Anadarko has previously said it was more likely to find gas
The report by Wellington-based data scientist Dumpark shows
the potential spread of a major deep-sea oil spill at the two
locations - in the Taranaki and Canterbury basins - Anadarko
is scheduled to test drill this summer.
The report was based on 1000 oil spill scenarios - ranging up
to the scale of the 2010 Deep Horizon disaster in the Gulf of
Mexico and smaller - using 10 years of global archives of
It showed oil would reach the shore of Taiaroa Head in 27% of
spills modelled in both summer and winter, and Oamaru in 31%
of spills in summer and 23% in winter.
This was in contrast to a high probability of ''dramatic
consequences'' in the event of a deep-sea blowout in the
North Island. Oil would reach the shore in all of the winter
scenarios modelled in most North Island locations.
The modelling showed oceanic currents and winds meant oil was
much more likely to wash up on the Chatham Islands than the
The Otago Daily Times will today seek comment from
Anadarko on the embargoed Dumpark report.
Dumpark data analyst Timo Franz said even if oil did not wash
up on the Otago coastline, it could still affect fisheries
off the coast and feeding grounds for marine birds.
Greenpeace campaigner Steve Abel said the report showed the
risks of oil drilling.
''This modelling suggests just how much of a threat deep-sea
drilling could be to our values, our seas, our beaches, our
way of life and our economic prosperity,'' Mr Abel said.
In the worst-case scenario for Taiaroa Head, oil would first
wash ashore in four days and in a worst-case scenario for
Oamaru, in three days.
A week after a worst-case scenario spill, there would be 14.9
grams of oil per square metre of water at Taiaroa Head, and
after six months there would be 23.8g/m2.
This was above the 0.01g/m2 threshold which resulted in the
closure of fisheries, the 1g/m2 which would require shoreline
clean-ups and 10g/m2 threshold which meant sea birds and
other wildlife could be killed.
A week after the worst case scenario for Oamaru, there would
be 2.7g/m2 and after six months there would be 16.2g/m2.