Evaluation of coseismic landslide hazard on the proposed Haast-Hollyford Highway, South Island, New Zealand

Robinson, T.R.; Davies, T.R.H.; Wilson, T.M.; Orchiston, C.; Barth, N.

Abstract

Coseismic landsliding presents a major hazard to infrastructure in mountains during large earthquakes. This is particularly true for road networks, as historically coseismic landsliding has resulted in road losses larger than those due to ground shaking. Assessing the exposure of current and planned highway links to coseismic landsliding for future earthquake scenarios is therefore vital for disaster risk reduction. This study presents a method to evaluate the exposure of critical infrastructure to landsliding from scenario earthquakes from an underlying quantitative landslide hazard assessment. The method is applied to a proposed new highway link in South Island, New Zealand, for a scenario Alpine Fault earthquake and compared to the current network. Exposure (the likelihood of a network being affected by one or more landslides) is evaluated from a regional-scale coseismic landslide hazard model and assessed on a relative basis from 0 to 1. The results show that the proposed Haast-Hollyford Highway (HHH) would be highly exposed to coseismic landsliding with at least 30–40 km likely to be badly affected (the Simonin Pass route being the worse affected of the two routes). In the current South Island State Highway network, the HHH would be the link most exposed to landsliding and would increase the total network exposure by 50–70% despite increasing the total road length by just 3%. The present work is intended to provide an effective method to assess coseismic landslide hazard of infrastructure in mountains with seismic hazard, and potentially identify mitigation options and critical network segments.

Citation

Robinson, T., Davies, T., Wilson, T., Orchiston, C., & Barth, N. (2016). Evaluation of coseismic landslide hazard on the proposed Haast-Hollyford Highway, South Island, New Zealand. Georisk: Assessment and Management of Risk for Engineered Systems and Geohazards, 10(2), 146-163. https://doi.org/10.1080/17499518.2015.1077974

• Journal Article Type: Article
• Acceptance Date: Jul 27, 2015
• Online Publication Date: Sep 22, 2015
• Publication Date: Apr 1, 2016
• Deposit Date: Oct 20, 2015
• Publicly Available Date: Sep 22, 2016
• Journal: Georisk
• Print ISSN: 1749-9518
• Electronic ISSN: 1749-9526
• Publisher: Taylor and Francis Group
• Peer Reviewed: Peer Reviewed
• Volume: 10
• Issue: 2
• Pages: 146-163
• DOI: https://doi.org/10.1080/17499518.2015.1077974
• Keywords: Exposure analysis, Hazard assessment, Risk management, Transportation networks, Lifelines, Haast-Hollyford Highway, New Zealand.
• Public URL: https://durham-repository.worktribe.com/output/1397252