A web-GIS and landslide database for South West Victoria and its application to landslide zonation

P.G. Dahlhaus, A.S. Miner, A. MacLeod and H. Thompson

The Australian Geomechanics Society’s (AGS) guidelines on Landslide Risk Management emphasise landslide zonation as a key requirement for regulators dealing with landslide risk (AGS 2007a). The basis for zonation is a landslide inventory which reflects the nature and spatial distribution of landslide types in a particular locale, such as a local government area. This paper describes the design and implementation of a web-based landslide database for south west Victoria aimed at disseminating landslide inventory information to regulators, consultants and the general public. Although the 4,581 mapped landslides represent the most complete and extensive data set for the region, the current data quality and resolution does not meet the AGS guideline for landslide zonation at the municipal planning scale. However, with an essential need for landslide planning controls in this region, the data is the best available for the construction of zonation maps, resulting in conservative boundaries at the required map scale. The paper highlights the ongoing need to improve the spatial extent and quality of the landslide database if the statutory planning zonation maps are ultimately to comply with the AGS guidelines.