Observational approach for urban landslide management

The occurrence of landslides in urban hillside areas poses significant challenges for risk management within residential suburbs as well as along road and railway lines. The main focus of this paper is the development of an “observational approach” for landslide risk management and its application within an important landslide study area, the Wollongong Local Government Area, in the state of New South Wales, Australia. Monitoring of subsurface shear movement and pore water pressures at a number of places in the study area during the last decade has already proved very useful in combination with rainfall data from a number of existing rainfall stations. Analyses of observational data have led to the assessment of rainfall triggering thresholds for the occurrence of landslides. Four new real-time monitoring landslide field stations have now been established for obtaining continuous data on subsurface shear movements, pore water pressures and rainfall in real time. The data is transferred automatically to a web-server and displayed on the web. These recent developments have resulted in a vast improvement in research techniques for understanding the initiation and progression of landslide movement triggered by rainfall. The data will prove to be very useful in the management of risk during rainstorms in real time or near real time. Moreover, over the medium to long-term, such accurate data will facilitate improvements in the planning and management of assets and land-use.