New Zealand’s National Landslide Database

Abstract

A New Zealand Landslide Database has been developed to hold all of New Zealand's landslide data and provide factual data for use in landslide hazard and risk assessment, including a probabilistic landslide hazard model for New Zealand, which is currently being developed by GNS Science. Design of a national Landslide Database for New Zealand required consideration of existing landslide data stored in a variety of digital formats and future data yet to be collected. Pre-existing landslide datasets were developed and populated with data reflecting the needs of the landslide or hazard project, and the database structures of the time. Bringing these data into a single database required a new structure capable of containing landslide information at a variety of scales and accuracy, with many different attributes. A unified data model was developed to enable the landslide database to be a repository for New Zealand landslides, irrespective of scale and method of capture. Along with landslide locations, the database may contain information on the timing of landslide events, the type of landslide, the triggering event, volume and area data, and impacts (consequences) for each landslide when this information is available. Information from contributing datasets include a variety of sources including aerial photograph interpretation, field reconnaissance and media accounts. There are currently 22,575 landslide records in the database that include point locations, polygons of landslide source and deposit areas, and linear landslide features. Access to all landslide data is provided with a web application accessible via the Internet. This web application has been developed in-house and is based on open-source software such as the underlying relational database (PostGIS) and the map generating Web Map Server (GeoServer). Future work is to develop automated data-upload routines and mobile applications to allow people to report landslides, adopting a consistent framework.

Landslide Scaling: A Review

“…Beyond the data compilations of individual authors, there are national data repositories online for landslide inventories in New Zealand (http://data.gns.cri.nz/landslides) (Rosser et al, 2017) and Italy (http://www.ceri.uniroma1.it/index_cedit. html) (Martino et al, 2014).…”

Monitoring active landslides in the Auckland region utilising UAV/structure-from-motion photogrammetry

“…The global importance of landslides was highlighted at the Fifth International Landslide Symposium in 1988, where it was proposed to develop a World Landslide Inventory to aid the United Nations in understanding the distribution of landslides and their causal factors. In New Zealand, recent coseismic (Massey et al 2018) and rainfall-triggered landslides (Harris et al, 2012) have led to the emergence of interest in monitoring and mitigating landslide effects, irrespective of the exact triggering failure mechanism (Rosser et al, 2017). Indeed, in New Zealand, landslides constitute a key natural hazard in many areas (Rosser et al, 2017), often driven by both high rainfall intensity and long rainfall durations (Harris et al, 2012), falling on sensitive soil substrates (Kluger et al, 2017;Phillips et al, 2018).…”

“…In New Zealand, recent coseismic (Massey et al 2018) and rainfall-triggered landslides (Harris et al, 2012) have led to the emergence of interest in monitoring and mitigating landslide effects, irrespective of the exact triggering failure mechanism (Rosser et al, 2017). Indeed, in New Zealand, landslides constitute a key natural hazard in many areas (Rosser et al, 2017), often driven by both high rainfall intensity and long rainfall durations (Harris et al, 2012), falling on sensitive soil substrates (Kluger et al, 2017;Phillips et al, 2018). However, although landslides occur frequently, because of the low population density, especially in the hilly and mountainous terrain, there are relatively few deaths compared to nations where mountainous terrain is more densely populated (Rosser et al, 2017).…”

“…Indeed, in New Zealand, landslides constitute a key natural hazard in many areas (Rosser et al, 2017), often driven by both high rainfall intensity and long rainfall durations (Harris et al, 2012), falling on sensitive soil substrates (Kluger et al, 2017;Phillips et al, 2018). However, although landslides occur frequently, because of the low population density, especially in the hilly and mountainous terrain, there are relatively few deaths compared to nations where mountainous terrain is more densely populated (Rosser et al, 2017).…”

Displacement mechanisms of slow-moving landslides in response to changes in pore water pressure and dynamic stress

“…These sedimentary rocks mostly comprise Neogene age, fine 30 grained sandstones and mudstones, which cover approximately 17% of New Zealand's land surface (Fig 1a) . The New Zealand Landslide Database contains approximately 7,000 landslides within these sediments (Fig 1b) (Dellow et al, 2005;Rosser et al, 2017), the majority of which are relatively slow-moving, deep-seated, translational slides that reactivate frequently (Massey 2010).…”