PROACTIVE MANAGEMENT OF SLOPE HAZARDS - WAIOEKA GORGE PILOT STUDY

摘要

Management of natural hazard risks, such as large landslides, has been a grey area forNew Zealand’s transport industry. The 2012 “Sandy Slip” event – SH2, Waioeka Gorge -was one such event.The resulting road closure spanned over 4 weeks costing the New Zealand TransportAgency $8M (NZD). We failed to predict either the timing or scale of the slip. Hence theWaioeka Gorge Slope Hazard Pilot Study was commenced in 2012 to answer twoquestions;i. Was Sandy Slip a one off event?ii. Explore the ability of remote monitoring systems to enable a more proactive riskmanagement system dealing with large scale slip risksThe gorge, poses a hazardous environment; very steep forested slopes up to 500m highand frequent rock fall events. This 3 part study focussed on large scale slip risks andinvolved rapid screening of the gorge, followed by detailed investigation of key sites.The intent is that remote monitoring of key failure features and the associated riskmanagement system will deliver early warning of slope failure, providing the tools toproactively manage slope risk.This paper discusses the development of the pilot study, including assessmentmethodologies and techniques and the study findings and outcomes.