It's only a matter of time before the Bay is hammered by a tsunami - and residents are being warned to get ready for the big one.
Images of the destruction wrought upon Southeast Asia this week, with the death toll now set to top 125,000, have shocked people worldwide.
They came as a scientific study for Environment Bay of Plenty and Environment Waikato found that at least six big tsunamis have crashed into our coastline in the past 4800 years.
The last time a big tsunami swamped the Bay was in the 15th century but 11 smaller ocean surges have hit our coastline in the past 150 years.
Local authorities now say Bay residents need to be more aware of risks and know what to do if a tsunami hits.
Environment Bay of Plenty's community relations group manager Bruce Fraser said most of the earlier tsunamis were probably caused by volcanic eruptions and earthquakes.
Most of them were small and they hit at favourable times, such as low tide.
However, the chain of underwater volcanoes that lie off the Bay coastline is a significant tsunami threat.
"They could come from off-shore earthquakes, like we've seen in Asia, or a seismic or volcanic event within a few hundred kilometres from our shore."
Mr Fraser said the surge in the Bay's population over the past few decades had heightened the potential for disaster. "With all the coastal development going on from Waihi to Ohope, we've increased our vulnerability."
In 1960, a Richter 8.5 earthquake in Chile triggered a 1m tidal surge that swept through eastern New Zealand damaging coastal jetties and boats.
Luckily, most homes along the Bay's coastline were baches in those days, Mr Fraser said.
"Whereas, now we have major settlements along a lot of the coastline." Mr Fraser said people living in the Bay needed to realise the reality and risks of tsunami.
"We know from surveys we've done that people here don't really perceive tsunami as a natural disaster threat."
In a 2003 survey, only 6.4 per cent of people recognised tsunami as being a significant threat to property and life in the Bay.
Most considered earthquakes as being the most devastating natural hazard.
Mr Fraser said it was impossible to know how much damage would be wrought to the Bay by a 10m tsunami like the one that swept across Southeast Asia.
The Earthquake Commission would provide insurance cover if the tsunami was triggered by an earthquake.
Homeowners would be covered up to the value of $100,000 for houses, surrounding buildings and land. House contents would be covered up to the value of $20,000.
If total damage costs exceeded the set EQC limit, most private insurers would also top up the costs.
Western Bay of Plenty District Council emergency management officer Alan Pearce said tsunami could take up to 13 hours to arrive here depending on how far away the triggering event took place.
"If a tsunami was on its way we would commence public broadcasts over the television and radio immediately and emergency service vehicles would move to the beach and get people to move inland and upland."
Mr Pearce hoped the recent catastrophic events would encourage everyone to take the threat more seriously.
"Everybody thinks this sort of thing will never happen here but I suspect neither did the people on those beaches the day it happened to them," he said.
"If a tsunami ripped up our coast then there will be staggering amounts of damage because of the relative low-lying aspects of our coast.
"A lot of the Western Bay is under 5m above sea level for several kilometres inland and it's bloody awful to think what a big wave could do here."
Geological and Nuclear Sciences seismologist and tsunami expert Gaye Downs said tsunamis that hit the Bay in the past could have been caused by underwater volcanoes between White Island and the Kermadec Islands. Mrs Downs said the 1960 tsunami triggered by an underwater quake off Chile took 13 hours to hit New Zealand.
The ocean surges lasted three days and caused waves of up to 4m around New Zealand.
Tsunami real threat to the Bay
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