Old Coast buildings under spotlight

Buildings inspectors say most of central Greymouth is not earthquake proofed, amid warnings that the Alpine Fault is overdue for a major rupture that could be much worse than the Canterbury quake.
One expert said a rupture on the Alpine Fault — which runs along the backbone of the West Coast — could unleash 32 times more energy than the quake that brought Christchurch to its knees on Saturday morning.
Professor Euan Smith, from Victoria University, said big earthquakes often came in clusters, and it was time to act.
“Owners of un-reinforced masonry buildings and chimneys everywhere in New Zealand should be given a reasonable period of time, say 10 years, to demolish them or make them safe in future earthquakes,” Prof Smith said.
The last big earthquake in Canterbury, in 1929 and measuring 7 on the Richter scale, was followed by the even larger and devastating 7.8 Murchison quake. The next 13 years saw seven major earthquakes with a magnitude greater than 7. This included the second and third largest earthquakes in European times — Murchison and Hawke’s Bay. The cluster ended with two 7.2 and 7 earthquakes in Wairarapa in 1942.
“It is more likely that the faults which broke during the series were all stressed and ready to break, and that the occurrence of successive earthquakes helped bring forward the occurrence of the next. There is no way of knowing whether or not Saturday’s earthquake has provided a trigger for more large earthquakes in the next few years.”
Grey District Council environmental services manager Ian Davidson-Watts, said “most” of central Greymouth was built from the 1900s onwards, particularly the 1930s and a lot of buildings were from a similar era to those that collapsed in central Christchurch on Saturday.
In Greymouth, the former Selwyn Traders building and neighbouring former Kingdom Hall, on Mawhera Quay, posed such a danger that the council was pursuing the case through the courts, he said.
“We are working hard to get it resolved.”
Issues were normally picked up when people applied for building consent, but the number of buildings not quake proofed was a “real issue”.
Buildings constructed in the past 10-15 years, such as The Warehouse and supermarkets, were up to modern standards.
Grey District Council senior building control officer Kevin Creagh said that when the Postie Plus building, in Mackay Street, was modernised the brickwork had to be reinforced, poles inserted in the walls, steel bracing put through the roof and trusses fixed to the walls properly.
“But there are a lot of buildings in Greymouth that could — and I stress, could — be likely to be earthquake-prone,” Mr Creagh said.
Dr Davidson-Watts said people complained about the building code but it had prevented fatalities in Christchurch.
“It reinforces the message that we are not out to get people. We are all waiting for the ‘biggie’ here.”
The West Coast District Health Board sparked controversy a couple of years ago when it said parts of Grey Base Hospital, which is less than 40 years old, were an earthquake risk.