Earthquakes and aftershocks

Last week was Disaster Awareness Week, and the “featured disaster” was an earthquake – a big deal for most New Zealanders, and especially those of us who live or work in Wellington. And while disaster awareness and preparation is of professional interest to me, there’s also the fact that earthquakes seem to have been quite significant in early Norgrove history.

Prior to the arrival of settlers, Maori were well-used to earthquakes. They had a word for them (ru) and an explanation – the god Ruamoko, son of Ranginui, the sky, and Papatuanuku, the earth, buried at his mother’s breast. Ruamoko is the god of volcanoes and earthquakes, and the earth’s tremors are caused by his subterranean movements.

Early settlers from 1840 onwards had already experienced many minor earthquakes, and one or two real doozies. On the 4th of December 1846, Wellington was jolted by a severe earthquake lasting several seconds, which caused people to run outside in panic. Perhaps not Sarah, though, as only the day before she had given birth to son Horace, and was probably still in bed recovering. There were at least 10 aftershocks over the next few days; then began a series of smaller earthquakes which went on for the next two years, about one a month.

Then on 16 October 1848 came the first major quake to affect Wellington. At about 1.40am on Monday morning, during a horrible night of severe gales and heavy rain, residents were woken, and in some cases thrown from their beds, by a major earthquake now estimated to have been of magnitude 7.5 on the Richter scale. The earthquake was actually centred in Awatere Valley in Marlborough, but was felt from Hawke’s Bay to Canterbury. The bulk of the damage was in Wellington, which was the most densely populated area at the time, with around 4500 settlers in addition to the Maori population. Three people in Wellington died as a result of the earthquake – a sergeant from the Mt Cook barracks, and two of his small children, who were buried by the collapse of a brick wall.

Sarah’s daughter Emma claimed to have been born during the earthquake, but in fact she was born during the tail-end of the big aftershocks, on 23 October. I have to wonder whether the shock and stress of the big earthquake and the ongoing aftershocks caused Sarah to go into labour prematurely; if that was the case, it doesn’t seem to have done Emma any harm, as she outlived the rest of her siblings and died at a ripe old age, two days after her 97th birthday.

In an attempt to “avert the recurrence of any similar visitation”, Lieutenant-Governor Eyre proclaimed Friday 20th October as a day of “public and solemn fast, prayer, and humiliation”. He also took the somewhat bizarre precaution of shifting most of the coinage from his treasury aboard a naval ship anchored in the harbour, although why he thought it would be safer there suggests how little he understood about earthquakes.

The 1848 earthquake badly damaged brick and stone buildings. Wooden buildings fared better, although many lost their brick chimneys. A major aftershock on the Tuesday afternoon finished off many of the buildings which had been badly damaged – fortunately by then the weather had improved, and people weren’t trying to keep the rain out of the holes where their chimneys had once been. On Wednesday morning the tide came in rather higher than it should have, and a number of Lambton Quay and Te Aro properties were inundated. William and Sarah and their family were living on Lambton Quay at this time – the houses here generally fared better in the earthquake than those at Te Aro and Thorndon, but didn’t escape completely because of the disastrous high tide.

We know that some time in 1849 the family moved from Lambton Quay to Thorndon Quay – could the 1848 earthquake have been a contributing factor in the decision to move? Was their house so badly damaged that they had to move? Did they think that Thorndon Quay might be safer in an earthquake? Or had William managed to put together enough money to buy a property rather than continue renting? Did they simply need more room, now that they had five children?

The next major earthquake was The Big One – a massive shock of 8.2 on the Richter scale, on 23 January 1855. This earthquake was on the Wairarapa faultline, and it visibly changed the landscape in ways that can still be seen over 150 years later.

Wellingtonians were in the middle of a two-day celebration of the 15th anniversary of the founding of the settlement. On the day before, there had been whale-boat races in the harbour; on the day of the earthquake, crowds of people had travelled to Miramar for horse-racing. Whether Sarah attended any of the events is unknown, but William and Ovid were still in the Victorian goldfields, leaving Sarah alone in the Thorndon Quay house with six children ranging in age from 12 (Oscar) to 2 (Kate).

At 17 minutes past nine on the Tuesday evening, the great earthquake struck. The first shock last 50 seconds, but must have seemed much longer as houses shook, windows broke, ornaments and furniture were thrown to the ground, and chimneys collapsed. Many people had trouble getting out of their houses because doors and windows jammed. The tide was high at the time, and the water level suddenly rose over two metres, flooding many of the shops and houses in Lambton Quay. The water then receded to a level several metres below the previous low tide mark, and for the next 8 hours it rose and fell every 20 to 25 minutes. A tsunami about ten minutes after the earthquake caused flooding in the sea-side suburbs, but didn’t have any appreciable effect in the inner harbour.

Most people spent the rest of the night outside, in makeshift tents or huddled in sheets and blankets, as the aftershocks continued. When daylight came, the extent of the damage was visible, from fallen and damaged to buildings to the unexpected change in Lambton Quay where the beach-front had experienced an uplift of about 1 metre. Many of the roads contained deep fissures which oozed mud. Aftershocks continued throughout the day, causing no little danger to the 65th regiment, who from daybreak had started pulling down the worst-damaged buildings. Amazingly, only one person was killed in Wellington, local identity Baron von Alzdorf, flattened by a falling chimney in his hotel.

Repairing the damage took months. How Sarah and the children coped is not known; however, it would seem that the earthquake brought William and Ovid home from Australia as fast as they could get there. In 1855, this wasn’t all that fast. It would have taken weeks for a letter from Sarah to reach William; in fact, it’s likely that he saw newspaper reports of devastation and catastrophe in Wellington, and immediately set off from the diggings, taking the first ship that would get him and Ovid back to New Zealand. This was the Wild Irish Girl, which landed them at Nelson on 10 May 1855. I haven’t yet found any record of how he and Ovid travelled back to Wellington, but perhaps a day or two spent looking around Nelson while waiting for a ship gave William a favourable opinion of the town, which had suffered much less earthquake damage. By October 1855, fourteen years after arriving in New Zealand, the whole family had removed to Nelson – driven away by Wellington’s shaky situation?