Living with 'The Earthquake'

First and foremost, hello and love to you all out there! :-) We've been quiet on the blog front for nearly three months – sorry to everyone far and wide about dropping off the radar. Our hometown of Christchurch had a 7.1 earthquake on 4th September, and really this earthquake has a lot to answer for!

While it was completely incredible that no one died in the event (which fortunately, if it's going to happen, occurred at 4.35am on a Saturday morning) and family and friends in Christchurch were all okay, our home in Christchurch (which we have been renting out while over in

Canada) was rendered uninhabitable - due to issues such as the chimney falling off, the

plumbing being ripped out in the wall, cracking in literally every single panel of gib in the house, walls no longer vertical, floors no longer horizontal and the house generally moving

eastwards on its foundations! So we found ourselves having to make the decision to head

straight for New Zealand and put off our travelling plans - apologies to all of you along the way in the US and UK that we were planning to visit, we'll get back your way, promise!

Once back in Christchurch, Frances's sister Kate, a geologist at the local University, took us out to see the fault rupture zone on the Canterbury Plains – the fault rupture extends 22km across

the plains, approx. 30km out of Chch and is the surface expression of the earthquake rupture – in other words, you can see where and how the earth moved, with cracks in the ground showing areas moving up to 4 m sideways, as well as vertical change. You stand in the fields looking at

the cracks displacing a road by 4 m, then think of the energy and sheer mass of earth that has moved in the area – phenomenal!

Line of fault rupture through paddock

This fence was straight - now it is off-set by ~4m. Headaches for the surveyors and property boundary definitions!

This road was dead straight - now the centre line lines up with the left edge markings, as the ground moved ~4 m north-east (right). You can also see some

vertical change in the trees on the left (higher to lower in the distance).

There are some pretty funny stories to come out of all this (we have to find humour in it all, right?) – like the homeowner near the fault rupture site who found the contents of their fridge in the oven when they got up in the morning after the earthquake. So during an earthquake, the strong motion is sideways shaking – you lurch one way, then back the other. During the earthquake, SLAM, the fridge door swings open, SLAM, as everything moves back the other way, the door of the oven opposite the fridge falls open, SLAM, back again and everything in the fridge falls across into the oven, BANG, the oven door jolts shut, BANG, the fridge door slams itself shut. Voila!

Some farmers woke up in the morning to find their nice flat paddock a mess of cracking and wonky fences and shelterbelts. It was a race for the scientists (such as the geologists from the University) to get measurements and information from the rupture zone, before farmers needed to plow the fields as the cracked ground caused a hazard to their animals who might trap a leg in the cracks.

Since the earthquake we have had over 2000 aftershocks. At my parents house, you can hear them coming – a low rumble starts a couple of seconds before it hits – just enough time to think - “oh here we go again, hope this one ain't too bad....". The sizes of the aftershock vary, but because the main event was a big event at magnitude 7.1, we have the occasional 5.something aftershocks, which are pretty decent. After these 5.something aftershocks, we have to go round to our house and shut it back up again, because most of the windows and doors fall open. We have aluminium framed windows with the usual handle latches, but the house is moving and twisting so much that the latches pop on the windows and the doors pops out of its lock. Everyone feels more aftershocks at night, largely because that's when you're lying still – you're not going to feel the small ones when you are moving round, cycling or driving. They have definitely become less frequent these last couple of weeks, but then we were woken yet again by one last night......

At our place, the front end of the lounge (to the right) has moved north from the main part of the house (this is the small end of the crack)

Typical cracking damage around doorways that many people have in their homes - however, our levels are all out and usually you don't have bits of plasterboard falling out!

Less visually obvious, but more significant in terms of structural integrity, we have fresh cracks through our foundation wall that have spat out concrete

The view under the floor - those concrete piles should be vertical!

While our house is uninhabitable, we are living between Frances's parent's house and her sister's house. Both their houses are fine, with Kate and Dave's property unscathed, while her parents had some significant liquefaction. It took them five days to clear their section of sand that was ejected from the ground during the earthquake. they have a lump in their driveway that grew for four weeks but seems to have settled down now, and their street was growing new lumps and potholes daily as the ground settled and moved after the quake. The land on our

section is undamaged, just soft and peaty as always, but we are looking at rebuilding on our section (as its not likely worth trying to repair our existing house) and this will give us the chance to get the foundations right for being on soft ground. The timeframe for all of this is a complete unknown – our insurance company has entered into a contract with a construction company and an engineering consultancy (which just so happens to be the company Frances works for!) to manage the process of repairing and rebuilding houses for their clients. From the earthquake, there have been over 120,000 claims made for either house or contents damage. In the big picture, for such an event, the way in which houses have come through the earthquake is actually quite incredible – so our house is one of the ones in the worst case basket, but it didn't collapse (other than the chimney falling off). The earthquake itself was of similar magnitude to Haiti's 7.0. There is a lot of learning and research going on from the effects of the quake and understanding how we can design and prepare for such events.

Since some suburbs of the city had significant liquefaction and laterally spreading (around river and estuary areas), the Earthquake Commission (our national earthquake and landslide insurance agency (government funded)) is looking at suburb-wide land remediation for those areas, to help prevent such extensive land damage happening in future big earthquake events. Therefore, for people whose houses are damaged in these areas, they will be waiting for this suburb-wide remediation to be decided on and done, before they can start to address their house repairs or rebuilds, so it is going to be a long-haul for many people. Some people will not be able to rebuild on their land because the ground condition is so poor in terms of liquefaction and spreading risk, and will be paid out for their house and land. There's a lot of high-pressure decision-making going on while trying to get this remediation done as effectively and efficiently as possible, and this also applies to other services such as water and sewer.

Both of us are working back in engineering now, and both working on some earthquake-related projects (assessing damage to land and water services). At times it feels a bit like we're living and breathing earthquake stuff at work and at home, but it is very good to be busy and useful! We have been house-sitting for Kate and Dave while they have been away overseas for the month (well, we say house-sitting, but actually it's cat-sitting their two cats, Sinbad and Apollo), then when they come back next week, we'll go stay back with Frances's parents for a while........

Meet the boys - Sinbad and Apollo - two of the biggest softies you've ever come across!

Apollo in a typical sleeping pose

Sinbad trying to sleep and hide from the world at the same time!

At Kate and Dave's the day our shipping arrived! Not that we could really unpack it anywhere - we've just shifted stuff around so we have essentials in a backpack and everything else is packed away either at Kate and Dave's place or parents' houses........

So there's a bit of a long post about the current legacy of this earthquake and the experiences around it. We'll try to get some more NZ photos up soon for those overseas – we have been away a few weekends to catch up with family and friends and also reacquaint ourselves with some favourite local places.

Take care

xxx

Neil and Frances