My reflections about how the earthquakes have changed our business since September 2010.
Just to put things into context we at Fox & Associates are very lucky. There was no loss of life and any physical damage we have individually suffered has been relatively minor. However in saying this everything we knew about Christchurch has changed as a result of the earthquakes – we now have a ‘new normal’!
4 September 2010
Although the initial September 2010 earthquake was huge, gave everyone a large fright and hit some residential areas very hard it did not generate a massive amount of earthquake related work for surveyors in general.
Fox & Associates was however engaged by the EQC to monitor Kaiapoi, Dallington and Horseshoe Lake areas and a number of private topographical or boundary definition surveys but there was not a large amount of other earthquake related work.
Much discussion was entered into as to the effect on the boundaries as a result of the September earthquake. Land Information New Zealand released new regulations (Rules for Cadastral Survey [Canterbury Earthquake] 2010) regarding the determination of boundaries of properties affected by the earthquakes.
22 February and 13 June 2011
Like everyone else we thought the September quake was as bad as it could get – February proved us wrong. Following the February quake we received a huge number of requests for building assessment and monitoring surveys.
Prior to the earthquakes we had not carried out a lot of building surveys so we have enjoyed the opportunity to exercise different skill sets but it’s obviously sad that this opportunity has come from such unfortunate circumstances. It means that we’ve spent time inside the cordon and around some of the worst hit streets and it can be disheartening seeing the sheer scale and extent of damage to land and buildings.
We hope that in playing our part in providing these measurements we are allowing the decision makers to make informed decisions and allow go forward with whatever direction they need to take.
We have used a variety of equipment including:
- Trimble GX Scanner – able to scan 4000-5000 points per second, creating a huge point cloud and photo image to provide a realistic model of whatever spatial area you wish to observe.
- Trimble S6 Reflector-less Total Station – an instrument that allows us to take measurements remotely and is particularly useful on measuring discrete positions such as corners of buildings or monitoring targets.
- Trimble DiNi Level – a very precise instrument capable of observing levels to 0.1 of a millimetre.
- Trimble R8 GPS units – survey grade GPS units that help us roam far and wide collecting data to assist with creating a strong frame work from which we use more precise terrestrial based equipment.
- Trimble Business Centre – a lovely piece of software that takes the hassle out of calculating least square solutions to provide the most accurate results from the recorded observations.
- AutoCAD Civil 3D – our CAD software of choice for three dimensional processing and presentation of data.
Some of the very interesting projects we have been involved with include:
- Land monitoring in Kaiapoi, Horseshoe Lake and Dallington – it has been interesting to track the changes in absolute position (Northing, Easting and Height) after each major earthquake and hear from the experts what is happening and what they expect to see next. On these projects we established a methodology and workflow that allowed us to install and monitor survey marks to an accuracy of 5-10mm (Vertical and Horizontal) over large areas. The data was observed using Trimble R8 GPS units and we process the data in Trimble Business Centre using Least Squares Analysis.
- Infrastructure surveys of fuel tanks in Lyttelton and Woolston and the associated fuel pipeline over the hill from Lyttelton to Woolston – we need to assess the shape and verticality of the tanks and provide as built data of any repair to the pipeline over the hill from Lyttelton to Woolston. This required a combination of Trimble DiNi Precise Level, S6 Reflector-less Total Station and R8 GPS units. All the data was collected and processed in AutoCAD Civil 3D providing a three dimensional model of the data to the client.
- Multi-storey buildings in the CBD – the majority of these projects included verticality and level surveys to support the assessment of the condition of the buildings. We used a range of equipment including using the GPS units to establish new control around the sites, S6 Total Station to observe the verticality at corners of the buildings, GX Scanner to observe large amount of data so as to assess the verticality and condition of the building facades and the DINI Precise Level to observe the levels of floors and establish precise levels of the benchmarks. There has been a huge range of styles of output to cater for the various uses of the data and preferences of the clients/engineers. We have received some great feedback about the quality of the data which is pleasing to hear.
- Observing the verticality of the CDHB chimneys on the various campuses. These are very tall structures with limited space to observe the full height of the structures. Some of these structures are tapered so the challenge was to observe enough of the surface that we could recreate the surface in the computer, slice sections through the surface so as to calculate the extent and direction of the lean of these structures.
Some of the earthquake memories that stick out in our minds include:
- David, Mike, Phil, Rebecca and Morgan being in the Price Waterhouse Building on the 22 February 2011 on Level 13. The surrealistic departure down the stairs and out of the inner city passing through the liquefaction and destruction.
- Vodafone ringing from our offices days after the earthquake offering to extract some essential items for us. A big thank you to Sandra from Vodafone.
- Carl, Mike, Mike Downs (big thanks) and Morgan being in town on 1 March 2011 extracting the remainder of our essential equipment and being at the Art Gallery at the time of the 1 minute silence / memorial. During the silence not hearing a single noise; cars, conversation, birds or diggers.
- Mike, Morgan, David Patterson and Jeff being at the intersection of Durham and Kilmore Streets when the 6.3 13 June 2011 hit Christchurch and watching the buildings swaying and particularly the Crowne Plaza opening and closing.
As mentioned above it has been interesting work but it does become a little disheartening to see damage day after day. From hereon we hope that we can continue to be meaningfully involved with the rebuild of Christchurch and the surrounding areas by being involved with the projects that will make a big difference to how we live and view Christchurch.
We as a city have an opportunity to create something special but it will take courage from the decision makers to make the difficult decisions, the designers to change the way in which we think about our designs and deliver our concepts but equally important is how the authorities assess the proposals. It cannot be business as usual because nothing is usual anymore – we have the ‘new normal’ to deal with, let’s make the new Christchurch special and the envy of the rest of the world.