Cliff Instability Areas (ASCCIE) - 2100 - 1.1m SLR

The ASCCIE_2100_1_1mSLR dataset is a digital dataset consisting of multiple spatial layer outputs from modelled erosion scenarios. The dataset is recommended for use at the statewide / regional scale along the Victorian coastline. Application of the data should be guided by the accompanying Victorian Coastal Cliff Assessment technical reports and expert advice. The product is not suitable for individual property scale assessments. Further information is contained in the study report "Victorian Coastal Cliff Assessment", Tonkin and Taylor, Sep 2023.\n\nConsolidated shorelines, which include soil and rock cliffs, are not able to rebuild following periods of\nerosion but rather are subject to a one-way process of degradation. ASCCIEs typically have two components:\n• Toe Erosion\nA gradual retreat of the cliff toe caused by weathering, marine and bio-erosion processes. This\nretreat will be affected by global process such as sea level rise and potentially increased soil\nmoisture. Future cliff toe position based on historical erosion rates with a factor applied to\nallow for the effect of future sea level rise.\n• Cliff Instability\nEpisodic instability events are predominately due to a change in loading or material properties\nof the cliff or yielding along a geological structure. In soft cliffs, instability causes the cliff slope\nto flatten to a slope under which it is “stable” (geo-mechanically). Soil cliff slope instabilities\nare influenced by processes that erode and destabilise the cliff toe, including marine\nprocesses, weathering and biological erosion or change the stress within the cliff slope. Most\nof the hard cliffs are stable at very steep angles. Instability events may range from small-scale\ninstabilities (block or rock falls) or discontinuities, to cliff slope instability cause by large-scale\nand deep-seated mass movement. The latter mode of failure in hard cliffs is rare.