When most people think of the earthquake in Christchurch, New Zealand, they remember the 6.3 magnitude tremors that shook close to the city's core in February 2011. 

That earthquake killed 185 people, caused more than $40-billion NZ in damage, and destroyed nearly half the downtown's building stock. 

But for former Christchurch resident Sarah Barr, it was the magnitude 7.1 crustal earthquake that struck six months prior that still haunts her. 

It happened at 4:35 a.m. on Sept. 4, 2010, 40 kilometres west of the city. Because of the quake's distance from the city, the damage was mostly to infrastructure — no one was killed, and few buildings collapsed.

Barr, who now lives in North Vancouver, was asleep in her family home in Christchurch that September night when she was first woken by the February quake's foreshocks.

She shared what happened next with CBC seismologist Johanna Wagstaffe as part of the Fault Lines series, which examines what could happen when the Big One eventually hits B.C.

Seismologists often compare what could happen in B.C. to what happened to people like Barr in New Zealand because we have such similar infrastructure, building codes and soil structure.

Sarah Barr

Former Christchurch, New Zealand resident Sarah Barr now lives in North Vancouver. She says she wasn't prepared for the 2010 earthquake that still haunts her, but she is now prepared for the Big One if and when it comes here. (CBC)

'And then it just hit'

Barr first felt the smaller tremors of the foreshock preceding the bigger quake. She said she wasn't worried at first, but that quickly changed.

"I went to turn on the light and there was no power ... And then it just hit. It was incredibly noisy," she said. 

Barr said her husband was in Spain at the time, so she quickly had to decide which of her two children, aged 1 and 3, to get to first. 

"My daughter was closer, and I heard her say, 'Mum!' And I said, 'Get under the bed!' 

"I tried to walk down the hallway and then I could hear her going, "Mum! Mum!" And I could tell she wasn't under the bed."

A bizarre game of Marco Polo ensued in the dark, with Barr and her daughter, Charlotte, shouting each others' names. 

"Finally I grab her, we go down the hallway, and it's like this sensation of being in a bouncy castle. It's like gravity boots on your feet," she said.

"We made it down the hallway to Daniel's crib, I grabbed him, and put both kids under the crib. And it's still going, and it's even louder now and I feel like the roof's going to collapse.

"I can't get under the crib, there's not enough room. So I try to pull over the changing table but the forces won't allow me, so I just get down on the ground and hunch next to the crib until it stops."

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A New Zealand Urban Search and Rescue worker walks through the central business district during a search of earthquake damaged buildings in Christchurch, New Zealand on March 2. ((Mark Baker/Associated Press))

The next day

The full impact of what had happened didn't hit Barr until the next day when she could see all the damage.

"I could see broken glass and stuff. [But] I didn't actually comprehend how bad it was until about mid-morning. The sidewalks were all cracked and the roads had some cracks in them," she said.

"And then there's this lovely term called liquefaction. It looks like mini-volcanoes of mud and dirt, only about half a metre or a metre high. Some of them have a bit of water coming out — like a school science experiment.

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Bill Wissink stands in water and liquefaction on his driveway in the suburb of Bexley, Christchurch, New Zealand. (Brett Phibs/New Zealand Herald/Associated Press)

"Other streets, they looked like they'd been flooded. They started off with water, and then as the water subsides, it's left with mud. And later on, of course, we heard that there could be sewage in there. And initially some kids played in it. You know, like a snow day with mud."

Barr said over the next few days, she had an overwhelming feeling of not wanting to leave her house

"Because your house is safe. It's still standing. It's like a tornado — your house can be fine and then three houses over it's completely torn apart," she said.

"Everyone looks shell-shocked. Everyone looks like a zombie, and they're on tenterhooks."

Family home destroyed

The Butcher family looks at what remains of their home in Christchurch, New Zealand, on Feb. 26, 2011. Powerful aftershocks continued to rattle the region. (Rob Griffith/Associated Press)

Months of aftershocks

"The first couple of nights, you get hammered by the aftershocks. I mean, it's all day. There's one every 20 minutes throughout the first week," she said.

"I actually brought the kitchen table into my bedroom. After the second or third night, I just ended up sleeping under the bed with the children because it was too scary.

Barr said at first every aftershock put her on edge. Other times, it was the smaller ones that were the most unnerving. 

"I kept all the lights on for about a week, because it was terrifying being in the dark," she said. "It's worse at night because no one likes to be disturbed [then]."

She described the collective trauma that her community experienced and the decades that it will take Christchurch to recover. 

Barr wasn't prepared for the earthquake but now, as a North Vancouver resident, she's prepared for the Big One. And she said that's why she feels she's able to live on the West Coast. 

Listen to CBC seismologist Johanna Wagstaffe's full interview with Sarah Barr.