Updating the landslide hazard assessment system within the City of the Gold Coast

The City of Gold Coast has a population of over 520,000 people and an area of 1400 square kilometres. The city has variable geology and geomorphology which includes significant amounts of sloping terrain. The project involved a review, revaluation and update of the city wide unstable soils and slope instability susceptibility zoning system and the detailed assessment of the existing planning scheme relating to the development on sloping sites of a medium or higher susceptibility of slope instability. The zoning was based on geology, landforms, climate and history of the project area using a GIS platform. The project incorporated current best practice guidelines for the assessment of slope instability risk and also included updating city wide susceptibility mapping showing numerous landslips that have occurred or been mapped since the original zoning was undertaken in 1999 by SMEC.