GNS Port Hills slope stability mass movement report released
Christchurch City Council has released the findings of the first of a series of reports looking at Port Hills slope stability post-earthquakes.
Prepared by the Institute of Geological and Nuclear Sciences Ltd (GNS Science) for The Council, ‘The Canterbury Earthquakes 2010/11 Port Hills Slope Stability’ Stage One report details investigations of 36 areas in the Port Hills where mass land movement has occurred. ‘Mass movement’ describes slope instability as a result of the movement of significant volumes of soil and/or rock. The report makes recommendations for further investigations and hazard reduction. The information in this GNS Science Report, and future reports in the series, will help guide decisions on land use and infrastructure planning and development, along with management and mitigation options.
View the MBIE 'Guidance for building in toe slump areas of mass movement in the Port Hills (Class II and Class III)' and FAQs.
More information on mass movement and the related GNS Science reports.
Rockfall risk model review 2012
Since issuing the GNS Science reports in 2012, some additional rockfall and landslide related fieldwork was done in the Port Hills. From this it became apparent that in a few isolated areas the rockfall risk models (and subsequent maps generated from these) did not appear to reflect the actual ground conditions in these localised areas. A review of the affected areas was carried out by GNS Science and Christchurch City Council geotechnical consultants.
View more information on the reissued GNS reports and maps.
Information, guidelines, updates and reports on Port Hills geotech issues