That Melbourne Water and other floodplain management authorities review flood models every five years and update the models at least every 10 years and after the occurrence of a major flood.

That the Victorian Government ensure that future flood mitigation efforts include updated and rigorous hydraulic modelling before implementation, ensuring the effectiveness of compensatory measures. Additionally, these strategies should undergo independent peer review to validate their expected performance.

That the Victorian Government fund floodplain managers to develop maps modelling scenarios demonstrating the impact on landholders of specified levee breeches.

That the Victorian Government work with floodplain management authorities and climate scientists to understand how flood modelling can be used to better predict the impact of climate change on flooding and update its flood management policies in line with this understanding.

That the Victorian Government provide Victorians with access to appropriate data contained within the FloodZoom platform

The Committee recommends the Australian Securities and Investments Commission consider seeking data from insurers on their performance based on the metrics recommended in Recommendation 51:
- Quarterly, for business-as-usual operations
- Monthly, for each declared event.

The Committee recommends that the Australian Securities and Investments Commission and the General Insurance Code Governance Committee share data so that it is possible to evaluate breaches of the General Insurance Code of Practice in the context of an insurers’ overall claims profile.

The Committee recommends the Australian Government and Insurance Council of Australia explore measures to facilitate the exchange of substantiated information about the resilience of a property to insurers, including new mitigation measures undertaken through state-based grant and loan programs.

The Committee recommends that the General Insurance Code Governance Committee publish aggregate data on code breaches by clause, individual insurer, and brand.

The Committee recommends that the Australian Government continue to work with the insurance industry through the Hazards Insurance Partnership to collate:
- data contained in the National Flood Information Database, and
- household-level data held by insurers (de-identified where appropriate).

The Committee recommends that the Australian Government ultimately move towards a national, centralised, public-facing portal containing flood risk data at the household level for:
- all households and small businesses across Australia, and
- all land being considered for release for development and all land that has been released for development, but not yet developed.
Agencies tasked with developing the portal should reflect upon governments’ past efforts to develop similar portals and lessons learnt. The portal should be easily accessible, user friendly and display high-quality flood risk information in a way that is readily understandable to communities. That before data is released on such a portal for existing properties (residential and small business), that the entity creating the flood study release that data through a staged process involving appropriate community consultation and engagement.

The Committee recommends that the Australian Government work with state and territory governments to ensure flood maps are produced to a high standard across the nation, regardless of the size of the local government area producing the modelling. This may require:
- increased funding for local government areas and water authorities, and
- the development of agreed standards to ensure that flood mapping is completed to at least an agreed minimum standard.
That, over time, this higher quality flood modelling be made freely accessible to homeowners and the general public along with easy to understand information about flood risk exposures at each property. This may be best undertaken in the first instance by local councils and/or water authorities responsible for generating the flood modelling, consistent with Recommendation 3 of the Actuaries Institute’s Funding for Flood Costs report (August 2023).

Melbourne Water should use the hydraulic model being developed (expected to become available in April 2024) to determine (and be subjected to independent peer review) the impact of the Flemington Floodwall and the efficacy of the associated downstream compensatory works.

Melbourne Water should adopt forecasting tools which enable forecasts to be made within a total of no more than 60 minutes.

Melbourne Water should ensure that their rating curves, which represent the relationships between river levels and corresponding river flows, extend also to rare and extreme flood events and have been derived using established bestpractice.

Melbourne Water should have a protocol that enables flood forecasting at intervals at less than two hours when prudent to do so by reason of the responsiveness of the catchment for significant events.

Melbourne Water needs to ensure that rainfall runoff and flood models are calibrated to observed flood information.

Melbourne Water should immediately update the Mid Maribyrnong flood model with a modern two dimensional flood model developed in accordance with Melbourne Water guidelines and use this model to set new design flood levels.

Melbourne Water should review their flood models every five years and update them at least every 10 years and after the occurrence of a major flood.

Melbourne Water should commission an independent expert review and audit of their forecasting system with the aim of identifying areas where forecast accuracy, warning times and model run times could be improved.

ICA data capture To provide greater transparency on the industry’s response to catastrophes, the ICA should develop a data dictionary to enhance industry-wide reporting and investigate the feasibility of extending data capture to other claim outcome measures such as closure rates, quality and complaints.

Insurers should improve data capture, modelling and reporting to assist with identifying and mitigating against factors that impact their ability to progress claims in response to a catastrophe, including bottlenecks (e.g. hydrology reports).

That the Flood Warning Consultative Committee considers the merits of delineating the Ouse River as a separate catchment from the Derwent River Basin.

That Government:
• undertakes a comprehensive assessment of flood mapping in Tasmania with a view to identifying data gaps, quality and currency, and works collaboratively with councils to identify funding to improve current statewide flood data; and • explores the feasibility of undertaking a comprehensive flood mapping of Tasmania, using LiDAR or other contemporary technology, with the objective of identifying which parts of our State are, and are not, prone to riverine flooding.

That agencies undertaking flood studies adopt a standardised approach, based on Australia Handbook 7, maintain public ownership of underlying data sets to support future modelling, and ensure open access to these studies.

That SES uploads current flood studies and plans to the Common Operating Platform as a flood plan layer and that councils, subject to resolving licence restrictions, arrange to have appropriate access.

That BoM and the Flood Warning Consultative Committee, in consultation with gauge owners, review flood gauges and develop a program to update data used to support hydrologic modelling. This should include reviewing gauge maintenance before and after floods.

Subject to funding, that the Flood Warning Consultative Committee investigates the hydrological matters and advice received during this Review and detailed in this Report in Sections 4.1.9 and 4.1.11.

In accordance with recommendations of the BMT WBM report, the Banana Shire Council, SunWater, and the Bureau of Meteorology, under the stewardship of the Department of Natural Resources and Mines, jointly identify the requirements for a suitable gauge network for the Callide Valley to allow meaningful and timely flood warnings. The review should identify key stakeholders, examine potential funding sources and include a cost benefit analysis.

All councils should, resources allowing, map the overland flow paths of their urban areas.

Councils should make their flood and overland flow maps and models available to applicants for development approvals, and to consultants engaged by applicants.

Councils should, resources allowing, maintain flood maps and overland flow path maps for use in development assessment. For urban areas these maps should be based on hydraulic modelling; the model should be designed to allow it to be easily updated as new information (such as information about further development) becomes available.

CS Energy should supplement physical monitoring of Splityard Creek Dam with visual monitoring by installing surveillance cameras or similar devices.

Seqwater should consider engaging a technical writer to develop completely new manuals after the operational strategies for Wivenhoe, Somerset and North Pine dams are set by the Queensland Government.

the state, in consultation with Bureau of Meteorology and Melbourne Water, take the necessary action to ensure that all flood warnings issued are linked to the geographical location of the gauge the data was derived from.

the state take into account any outcomes from the Commonwealth Government’s flood mapping reviews in the continual development of the Victorian flood database and to incorporate into the database flood data currently held by Melbourne Water.

the state establish standards for flood mapping to ensure they are kept contemporary and meet the purposes of landuse risk planning and emergency response. In doing so, maps should extend where appropriate to include Probable Maximum Flood, over a range of Annual Exceedence Probability levels and be explicitly linked to a stream gauge.

the state ensure that regional and local flood plans incorporate all available flood mapping and intelligence, including assessments of levees and flood consequence information.