The 2023 extreme weather events
The beginning of the year was marked with the significant weather events that affected many areas across the upper North Island.
Rainfall recorded over the summer of 2023 in parts of the North Island broke all-time records, with the February 2023 ex-tropical Cyclone Gabrielle being one of the worst weather disasters in the history of Aotearoa. Based on data published by NIWA, it was the wettest summer on record for several major centres, including Napier, Auckland, Whangārei, Gisborne, and Tauranga. A huge contrast was the summer in the South Island, which was the 5th driest on record.
Last summer’s extremely warm and wet weather is primarily attributed to the La Niña phenomenon. This brings stronger than usual winds from the equator pushing warm weather from the Pacific towards New Zealand, bringing moist and rainy conditions to the north of the country. This is not an unusual phenomenon; however, its effects could have been exacerbated due to climate change. A study by the World Weather Attribution published in March 2023 found that the rainfall from ex-tropical Cyclone Gabrielle could be about 30% heavier potentially due to climate change.
The response of our profession
Heavy rain brought destruction in the areas of the North Island hit by the extreme weather. Rivers rose rapidly overtopping or even breaching stopbanks, causing devastating floods in urban and rural communities and the tragic loss of 11 lives, together with power and communication outages, road collapses or blockages, landslides, destruction of homes, farms, and public infrastructure. The resilience of our built environment was tested once again and unfortunately, it did not pass with flying colours.
Geotechnical engineers were in the line of fire once again. They have been in the heart of the response and recovery efforts in this recent natural disaster event, as was the case in previous natural disasters; some examples include last year’s flooding in Nelson, the widespread landslips in Wellington in 2021 and 2022, and the less recent Christchurch and Kaikoūra earthquakes. Our profession is again under pressure to deliver a huge workload of response and recovery works, in an environment where the availability of geotechnical engineers was already stretched beyond local capacity before the events.
The NZGS volunteers, contributing either in the local NZGS branches or the NZGS Management Committee are no exception to the above situation. They are part of the response and the recovery efforts and are experiencing a huge workload. Despite this, the Society continued to progress its activities over the first half of the year, very much aligned to upskilling the industry to be able to respond to such disaster events and assist our communities become more resilient and prepared in the future.
NZGS have a dedicated working group on issues related to Climate change, which was formed last year and kicked off its activities in March 2023. An update on the activities of this group is provided by the leader of the group Martin Larisch, in this issue of the magazine. NZGS will seek opportunities to collaborate with other local or international groups working on Climate Change initiatives. We have also started planning for our 2nd Climate Change Symposium, more information on this to follow in the next few months.
I would like to wholeheartedly thank all those involved in one or the other way in the NZGS activities and for their passion to continue delivering for the Society, despite the emergency conditions and heavy workload of the past months.
NZGS training programme
A big item of the NZGS activities this year is our training programme. Two training courses were delivered in March 2023 by international experts. The first was on “Soil Slope Stability Analysis, presented by Professor Vaughan Griffiths from the Colorado School of Mines. This course was oversubscribed and NZGS decided to increase its capacity to respond to the high demand. The course received very good feedback and the expressed desire of our members to continue with more courses on this subject in the future.
The second course was on the use of “GIS for Geotechnical Professionals” delivered by Colin Mazengarb, former engineering geologist of the Tasmanian Government (Mineral Resources Tasmania). This was a very successful delivery of the series of courses that Colin has been presenting for AGS and NZGS in Australia and New Zealand and more of these will come, as there is a big demand.
We have at least two more in-person courses planned for the second half of the year. A dream team consisting of Brady Cox from Utah State University, Liam Wotherspoon from the University of Auckland, Andrew Stolte from the University of Auckland and Joe Vantassel from Virginia Tech will offer a two-day course on the in-situ seismic investigation methods. The course will focus on in- situ seismic investigations and the translation of seismic measurements into site classification metrics such as Vs30 and fundamental site period. This course is very topical, considering the changes expected in the future following the release of the NSHM. I should note that any surplus made from this course will be donated to Disaster Relief Funds to support Cyclone Gabrielle’s recovery.
We are planning for one more international expert on earthquake geotechnical engineering to visit New Zealand towards the end of the year to deliver training to our members. Professor George Gazetas, Emeritus Professor of the National Technical University of Athens will be visiting to deliver courses on Earthquake Geotechnical Engineering, potentially focused on foundations and soil structure interaction. We look forward to this event, currently expected to be delivered to four centres across the country. We are working closely with Prof. Gazetas to develop a course aligned with local practice and enriched with his international experience.
A webinar of Module 3 of the MBIE/ NZGS Earthquake Geotechnical Engineering Practice Series presented by Misko Cubrinovski from the University of Canterbury has also been announced for June 2023.
I would like to thank Emilia Stocks from Tonkin and Taylor, our training coordinator for the hard work she is doing organising all these courses for our members. Emilia works with enthusiasm and passion, and we cannot express our appreciation enough for her efforts.
The successful programme of webinars from a wide range of local and international experts is also ongoing, with two already delivered this year and others in the pipeline. This webinar programme is kindly organised by Rolando Orense from the University of Auckland. You may find the recorded webinars on our website.
NZGS continues working with the key industry stakeholders and advocating for the important matters of the geotechnical profession.
NZGS has representatives on the MBIE Seismic Risk Working Group (Rick Wentz from WENTZ-PACIFIC LTD), the Joint Committee for the Seismic Assessments of Existing Buildings (Stuart Palmer from Tonkin and Taylor and Phil Clayton from BECA) and on other working groups exploring the incorporation of new science into the Building Code and Standards. NZGS is also supporting MBIE for the development of the New Zealand Geotechnical Database with the kind contribution of Ross Roberts on behalf of NZGS, John Scott from Wellington Water and Tracy Howe, from Tracy Howe Consulting.
NZGS has also nominated representatives on the Engineering New Zealand CPEng Board (Geoff Farquhar from GHD), the Bodies of Knowledge and Skills Working Group (Pathmanathan Brabhaharan from WSP) and the Natural Disasters Recovery Panel (Tony Fairclough from Engineering Geology Limited).
NZGS on air
NZGS was pleased to nominate respected members of the geotechnical community to participate in the Radio New Zealand “Nights with Karyn Hay” show, to inform the public on aspects of geotechnical engineering. This was a kind invitation to NZGS by Michelle Grant, Immediate Past President of SESOC, who has a regular spot on this show.
Two sessions related to geotechnical matters have been presented to date. The first one was delivered by Alex Cartwright from Tonkin and Taylor and was focused on natural hazards, in particular flooding risk preparedness and response in the light of the North Island weather events. The second was presented by Tony Fairclough, former NZGS Chair and Managing Director of Engineering Geology Ltd and was focused on the role of geotechnical engineers and engineering geologists in building robust and resilient infrastructure.
You can catch the two broadcasts on rnz.co.nz/national/programmes/nights. There will be more sessions on geotechnical engineering, with the next programmed for July 2023. Watch our newsletter for more detailed information on this broadcast.
Earlier this year we were delighted to issue the “Ground Anchors: Design and Construction Guideline” as a draft for comment by the industry. This is a great document, put together by a group of subject matter experts under the leadership of Sam Glue from BECA. I would like to thank the team for their hard work and dedication in preparing this guideline. We welcome the input from the industry to make the document even better and useful for our members. Consultation on the document closes at the end of October 2023. After finalisation, NZGS will be holding a series of presentations at local branches across the country to outline what is in the guideline and how to use it for future projects.
I am also pleased to report that Unit 1 of the Slope Stability Guidance Series is progressing very well under the leadership of Richard Justice from ENGEO and the valuable support of Toka Tū Ake EQC and MBIE. The plan is to have a first issue of Unit 1 for comment by the industry by the end of this year.
NZGS upcoming elections
The call for nominations for the next NZGS Management Committee will be issued sometime in June 2023. I encourage all members who are passionate for the profession to submit a nomination. All you need is your determination to contribute and your intention to devote some of your time to this cause. We are intending to increase the number of people contributing to NZGS, so that the huge workload we are delivering can be shared among more people.
My two-year term as NZGS Chair is ending in October 2023. Although my involvement with NZGS will not end with the end of the Chair’s term, I would like to take this opportunity to share what I have gained through my nearly eight-year long journey with NZGS.
My involvement with different NZGS roles and activities provided unique professional experience and development, different to the one gained through a technical project environment. I had the opportunity to meet and work with many local and international leaders in the field as part of short courses, technical lectures, workshops, and conferences. I had the opportunity to participate in interesting debates and humbly contribute my little bit to the advancement of geotechnical engineering in Aotearoa for the good of the wider community.
Above all, I had the privilege and pleasure to interact with the wider geotechnical industry in New Zealand (and overseas) and to serve a wonderful membership of knowledgeable, passionate, and innovative people, who inspired me to keep improving.
I encourage you to be involved with NZGS, it certainly is a rewarding experience.
Wellington, May 2023