Massey, CI & Palmer, N 2007, 'Monitoring Landslide Movement and Triggering Factors in Near Real-Time - Examples from Translational Landslides in New Zealand', in Y Potvin (ed.), Slope Stability 2007: Proceedings of the 2007 International Symposium on Rock Slope Stability in Open Pit Mining and Civil Engineering, Australian Centre for Geomechanics, Perth, pp. 439-447, https://doi.org/10.36487/ACG_repo/708_29
(https://papers.acg.uwa.edu.au/p/708_29_Massey/)
Abstract: The Taihape landslide covers approximately 45 hectares and contains over 200 households a primary school 
and a hospital. The Waikorora landslide covers approximately 6 hectares and is traversed by the Maui gas 
pipeline, which provides New Zealand with 80% of its gas requirements. Both landslides are currently active 
and are being monitored using a combination of field mapping, sub-surface investigation and near real-time 
monitoring of rainfall, ground-shaking intensity, groundwater levels and surface movement. Data from the 
landslides are being used to correlate different rates of surface movement to the triggering factors enabling 
movement triggering thresholds to be established. Until 2006, monitoring was carried out manually, with the 
monitoring frequency ranging from twice a year to once every five years. New monitoring equipment 
operating in a near real-time framework was installed in 2006. A key component are the surface movement 
monitoring systems which, at Taihape, comprises a laser survey network that automatically tracks, at defined 
(hourly) intervals, the positions of reflectors placed on the landslide; and at Waikorora, a series of 
continuous GPS receivers installed on the active landslide. These movement data, along with data from 
piezometers, rain gauges and strong motion accelerographs installed on the landslides are transmitted by 
radio and internet to a central hub where they can be viewed in near real-time. The greater temporal and 
spatial resolution of the monitoring networks allow movement triggering intensity/duration thresholds to be 
developed, which will allow alert levels, based on landslide movement to be set, once a better understanding 
of the movement patterns have been established.