Victorian Coastal Cliff Hazard Assessment 2023

The Victorian Coastal Cliff Assessment, Stage 2a (the product) is a digital dataset consisting of multiple spatial layer outputs from modelled erosion (cliff instability) susceptible areas and risk assessment scenarios.

The product is an update to the Victorian Coastal Cliff Assessment, Stage 1. Included datasets for Stage 2a supersede the Stage 1 outputs. The Stage 2a project report should be read in conjunction with the Stage 1 report.

The product 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, Stage 2a technical report (Tonkin & Taylor 2025) read in conjunction with the Stage 1 technical report, combined with appropriate expert advice. The product is not suitable for individual property scale assessments.

The datasets available are as follows with further detail on technical assumptions for these scenarios are provided in the accompanying technical reports. Additional data sets referenced in the reports are also available on request.

1. Areas susceptible to coastal cliff instability and/or erosion (ASCCIE) Description: Hazard area at top of cliff, for multiple sea level rise scenarios • ASCCIE_PRESENT_DAY_00MSLR • ASCCIE_2040_02MSLR • ASCCIE_2070_05MSLR • ASCCIE_2100_08MSLR • ASCCIE_2100_11MSLR • ASCCIE_2100_14MSLR

2. Areas Susceptible to Talus Runout (ASTaR) Description: Hazard area at based of cliff, for present-day scenario • ASTAR_PRESENT_DAY_00MSLR

3. Coastal compartments aggregated cliff risk ratings Description: Cliff-related risk assessment rating, for short-term, medium-term and long-term • CLIFF_RISKSCORE_SHORTTERM_TO_2040 (Cliff risk rating, short-term; now – 2040) • CLIFF_RISKSCORE_MEDIUMTERM_2040_2070 (Cliff risk rating, medium-term; 2040 – 2070)
   • CLIFF_RISKSCORE_LONGTERM_2070_2100 (Cliff risk rating, long-term; 2070 – 2100)

   Data attributes for risk include: • Human health and safety • Access / lifestyle • Environmental • Cultural • Property • Infrastructure • Economy and growth

Forming the aggregated risk rating per coastal compartment

Risk assessment ratings are aggregated for coastal compartments listed below: Coastal Compartment Code Location VIC01.01 Mallacoota Inlet VIC01.02 Croajingolong VIC02.01 Snowy River VIC02.02 Gippsland Lakes VIC02.03 Corner Inlet VIC03.01 Wilsons Promontory (east) VIC04.01 Wilsons Promontory (southwest) VIC04.02 Waratah Bay VIC04.03 Venus Bay VIC04.04 Kilcunda VIC04.05 Phillip Island (south) VIC04.06 Western Port VIC04.07 Cape Schanck-Flinders VIC04.08 Mornington Peninsula VIC04.09 Port Phillip Bay (east) VIC04.10 Port Phillip Bay (west) VIC04.11 Port Phillip Bay (mouth) VIC05.01 Torquay VIC05.02 Great Ocean Road VIC06.01 Port Campbell VIC06.02 Warrnambool VIC06.03 Portland Bay VIC06.04 Discovery Bay

1. Cliff-toe public exposure rating Description: High-level assessment of potential level of public exposure to cliff instability hazards at the cliff toe • CLIFF_PUBLIC_EXPOSURE

   Data attributes for Public Exposure include: • Beach Usage • Hazard Exposure Time • Public Exposure Rating