Queenstown, April 2026
The New Zealand Geotechnical Society has successfully bid for and won the rights to host an international conference on landslide risk. Proposed as a joint conference of two Joint Technical Committees, such an event has never been attempted in the past. Our proposal was warmly welcomed by the three International Societies that NZGS represents in New Zealand and by our colleagues in the Australian Geomechanics Society. Sign up now on our conference website http://landsliderisk.nz/ to ensure you’re kept informed about this exciting event.
1. Background
In September 2024 the NZGS management committee made an offer to the Chairs of Joint Technical Committees 1 and 3 (Gonghui Wang & Jean Hutchinson) and President of FedIGS (Chungsik Yoo) to host a combined workshop of Joint Technical Committees 1 and 3. Because of recent events and ongoing research in New Zealand, we believed that 2026 would make an ideal time for New Zealand to host an international event of this nature.
The events of 2023 have heightened our national awareness of landslide hazards, and driven significant efforts into policy, research and risk communication. We saw great benefits to bringing international researchers and practitioners to New Zealand to collaborate on the many activities that we are undertaking to better understand, mitigate and communicate landslide risk.
We have a long and successful history of hosting conferences, and we are confident that we can make this a fantastic event.
2. Location
We have selected Queenstown as our preferred location. It is a great attraction for our overseas guests, but more importantly is highly exposed to geological hazards. Surrounded by active and relict landslides, Queenstown makes a perfect backdrop for this workshop and an ideal venue for field trips.
3. Date
In 2026 a series of projects in New Zealand will be at an ideal stage to present to an international audience, and to receive input and feedback. An introduction to these projects is given later in this article and should ensure that there is plenty of local academic and technical content.
This date also aligns well with what we hope will be the end of most of the recovery work from our 2023 national emergency, meaning that we should have plenty of local practical content and lessons to share.
We are proposing for the conference to take place in the week commencing Monday 27 April 2026. This avoids peak tourism times around Easter and puts the conference at a time of year that should work well for academic calendars, particularly in the northern hemisphere.
4. Draft programme
We will work on our programme with JTC1 and JTC3 representatives. Our current draft programme includes:
1. Day 1 – training and courses
2. Day 2 – Susceptibility to risk
3. Day 3 – Risk to policy
4. Day 4 – Risk communication and education
5. Day 5 – Field trips
More details are available on the website and will evolve as we clarify details with the Joint Technical Committees.
5. Sustainability
One of our reasons for choosing Queenstown as a venue is their commitment to achieving a regenerative tourism and a carbon zero visitor economy by 2030. We are working on plans to make this the most sustainable conference ever hosted by the New Zealand Geotechnical Society.
6. Possible field trips
We will collaborate with the Joint Technical Committees and local volunteers to confirm field trips, which are expected to include the following.
6.1 Clyde Dam
With a focus on landslide investigation and remediation, this trip to the Clyde Dam will pass through Kawarau and Cromwell Gorges. The Clyde Dam started generating power in 1993 and it was the last major hydro-electric scheme to be completed in New Zealand. It was a controversial project, with widespread opposition from local residents and environmentalists. The presence of landslides in the Cromwell gorge had long been known and shown on geological maps but were not believed to pose major problems as they were thought to be ancient and inactive. The known landslides were monitored during the construction phase, and it was discovered that some ’dormant’ slides in the Cromwell gorge were slowly moving downhill. Exploratory drilling for a new highway led to the discovery of a complex, high-pressure groundwater system, and this led on to an extensive drilling programme on other landslides.
A strategy was developed for a fast-track stabilisation program, based primarily on the use of tunnels for both investigation and drainage. All known landslides were re-mapped in detail, combined with drilling and tunnelling. Up to 40 geologists worked on the landslides over a two-year period – it was the largest engineering geological investigation ever undertaken in New Zealand. Gravity drainage was the main method of remediation combined with grouting, buttressing, pumped drainage and continuous monitoring. Construction of the Clyde Dam took much longer than anticipated, with a final cost more than 45% above the original estimate.
This tour will include visits to the stabilised landslides showing the scale of work undertaken and sharing lessons learned.
6.2 Glenorchy Resilience Project
With a focus on education, natural hazard communication, and community resilience this trip will visit the stunning village of Glenorchy. Surrounded by magnificent snow-capped mountains, Glenorchy sits a spectacular 45-minute drive from Queenstown.
Glenorchy’s soaring peaks, pristine lakes, glacial rivers, and ancient beech forests are a dream destination for outdoor adventures. Home to New Zealand’s finest hiking, the awe-inspiring scenery has formed the backdrop for films like Narnia, The Hobbit and Lord of the Rings.
With this beauty comes risk. Glenorchy is directly exposed to risks of flooding, earthquakes and liquefaction, and is very vulnerable to being cut off by landslides. In a large earthquake it would likely lose access to all major utilities. To manage this risk, detailed studies have been undertaken ranging from better understanding the hazards through to socio-economic impacts.
A natural hazards adaptation strategy was developed in partnership with the local community. This tour will investigate how the strategy was developed and is being implemented with the community.
6.3 Milford Sound Landslide-induced Tsunami Cruise
Deep within Fiordland National Park lies Milford Sound, New Zealand’s most stunning natural attraction. With its magical combination of mountain peaks, ink-dark waters and superb dramatic forest-clad cliffs, it must be seen to be believed.
It is also the only fiord in New Zealand that is accessible by road. However, its remote location, bounded by steep cliffs and dense rainforest, means its special features remain unspoilt. Rain or shine, Milford Sound continues to captivate even the most experienced traveller with its beautiful surroundings, ink-dark waters, gushing waterfalls and captivating views.
A million people a year visit Milford Sound. The nearby Alpine Fault ruptures, on average, every 330 years with a magnitude 8 earthquake, and this would likely cause a very significant rockslide. Geological evidence suggests that this has happed at least 30 times before. With only one route out, evacuation planning is extremely challenging. A recent Master’s thesis has found a Milford Sound landslide-triggered tsunami may leave no survivors, with as many as 3500 dying if the wave hits during the peak of the tourist season. The best-case scenario shows 5.2 percent of people would survive the wave, and in this case the tsunami would have to hit at night, during the winter off-season, when only a few hundred people would be in the area.
This field trip will explore the decision-making process required to balance the public interest in visiting this natural wonder with the potential risk it poses.
7. Supporting programmes
This workshop-style conference will bring together local and international researchers and practitioners to share their expertise for the benefit of several key programmes of work underway in New Zealand.
7.1 Sliding Lands – Hōretireti Whenua
The Hōretireti Whenua Sliding Lands programme will create national-scale landslide models that can forecast where rapid and dangerous landslides are likely to be triggered by earthquakes and rainfall events.
This five-year research programme is funded $10.5 million from the MBIE 2023 Endeavour Fund and is led by GNS Science, with research partners Massey University, Manaaki Whenua Landcare Research, Te Runanganui o Ngāti Porou, Market Economics, University of Auckland, Resilient Organisations and University of Canterbury.
GNS Science is working with iwi partners, international collaborators from the UK (Durham University) and Switzerland (ETH Zurich) and stakeholders from central and local government.
The models will use susceptibility factors such as rainfall, ground shaking, vegetation type, and slope gradient to determine the likelihood and locations of fast-moving landslides across the country for earthquake and rainfall triggers. These susceptibility models will be combined with landslide runout models and vulnerability models to predict the hazard and risk from landslides. From this information our models will determine what the impacts may be, particularly to people, property, industry, and the environment.
The programme will also investigate people’s perception of landslide phenomena, hazards, and the models we develop to understand the risk and impacts of landslides, as well as their perceptions of vulnerability to landslides. Findings will be used to improve the communication and visualisation of model outputs around risk, as well as inform the development of the models themselves.
The effectiveness of the landslide models will be tested and refined using two case studies based in Tairāwhiti and Auckland.
7.2 Landslide Watch Aotearoa
Also funded for five years by MBIE’s Endeavor Fund, this programme aims to move away from expensive local reactive (post-event) in-situ monitoring to pro-active (pre-event) space-based observation across all Aotearoa.
Led by GNS Science, this work will be in collaboration with NIWA, University of Waikato, University of Canterbury, University of Leeds (UK), University of Oregon (US), University of California (US), University of Washington (US) and the Disaster Prevention Research Institute, Kyoto University (Japan).
While the Sliding Lands work pays most attention to rapid, first-time slope failures that create obvious scars in the landscape and have immediate consequences, this second programme focuses on a slightly different hazard. Many landslides are pre-existing, large, deep, slow-moving and persist for generations; they damage homes, infrastructure and sometimes accelerate to fail catastrophically. Forecasting when a landslide might transition from slow to fast depends on our ability to identify the movement, constrain its mechanism, and model that movement under different driving conditions. Until now, methods used to find and predict the occurrence of damaging landslides faced considerable limitations, with traditional ground-based monitoring being too costly, time-consuming, and offering limited spatial coverage. The team propose to use satellite data (InSAR) to detect slow-moving landslides, link their movement patterns to the climatic drivers and characterise their behaviour before they cause damaging and/or catastrophic impacts.
This ambitious approach will enable landslides to be identified nationwide, link their movement patterns to climatic drivers, and characterise their behaviour before they cause damage.
7.3 Landslide Risk Management Guidelines (AGS2007 update project)
The AGS guidelines represent current best practice for landslide risk management in Australasia, and are freely available online at https://landsliderisk.org/. The New Zealand Geotechnical Society and the Australian Geomechanics Society are working in partnership on an update to the guidelines to reflect lessons learned since they were published in 2007.
This work is expected to be approximately 80% complete by April 2026, and the conference will be used as an opportunity to involve international experts on this important project.
7.4 Geo-education Roadshow
The New Zealand Geotechnical Society is taking a series of actions to engage with its members and relevant stakeholders to explore issues relating to the availability of a skilled workforce in New Zealand. The objective is to finalise a position and an action plan for NZGS that will include the different perspectives and to advocate for improvement. This work will be continuing over the coming years and will use the 2026 landslide conference to share our experiences with an international audience, and to learn from their successes and challenges.
7.5 University of Canterbury PMEG relaunch
UC’s Professional Master of Engineering Geology (PMEG) is the only programme of its kind in Australasia. It concentrates on professional training for practitioners. The PMEG is strongly applied and concentrates on professional training for practitioners, delivered in a 12-month format. Having been closed to new enrolments for several years, it is forecast to take its first new intake of students in early 2026.
This conference will help provide a springboard for the field-based elements of the programme, bringing in international expertise to support the team, and has the potential to deliver a significant field-based training programme alongside the conference.
8. Conclusion and next steps
The enthusiasm with which JTC1 and JTC3 responded to this proposal, and the opportunity to involve international expertise in these fascinating projects, means that we’re confident this will be a very successful and useful event.
We encourage everyone to visit the conference website at http://landsliderisk.nz/ and register your interest. This way you can stay informed about announcements.
We’re looking for additional volunteers to help organise the event and field trips, and for potential sponsors who would like to showcase their business to a large audience of local and international experts.
