The study itself does not create a new risk to properties; it is qualifying an existing flood risk.
Some properties are already identified in the Boroondara Planning Scheme as likely to flood due to a 1 in 100 year ARI rainfall event.
As a result of this new study, approximately 4,300 additional properties in Boroondara have been identified as at risk.
On this page:
- Flash flooding and insurance
- Information specific to your property
- No noticeable effect on property values
- New Report and Consent requirement for building works
Any property within the municipality is potentially at risk of storm damage resulting from flash flooding, regardless of whether they have been identified by the flood mapping study or not.
The study identifies the risks of ‘flash flooding’ and stormwater rainfall run-off, which are included under storm damage provisions of domestic insurance policies.
This is different from the definition of ‘flooding’ provided by the Insurance Council of Australia, and does not relate to flooding from rivers or creeks.
The information provided by the study can help residents to minimise losses resulting from future flash flood events but we recommend you contact your Building and Home and Contents insurer if you want to know whether flash flooding from overland stormwater flow is covered in your policy, and to what extent.
If your property is affected, we have notified you by letter in October 2017 and you can apply to Council for flood level information specific to your property.
Free information will be provided for basic details such as likely extent and depth of flooding.
Once the results of the study have been incorporated into Council’s information systems, a fee will apply for a formal flood level application, which will include an assessment of how proposed buildings or works should be modified in order to satisfy the relevant provisions of the Victorian Building Regulations.
To determine whether the introduction of a flooding overlay will have an impact on property values, we looked at the site values of a sample of properties before and after the introduction of the Melbourne Water Special Building Overlay (SBO) in 2006.
The analysis considered the change in property values over a four-year period spanning the introduction of the SBO. For the properties analysed, the average site value increase for properties located within the SBO was 88 per cent, which is only marginally below the 89 per cent increase in site values for properties located outside of the SBO.
Once we have designated within our internal information systems that properties are subject to flooding, Licensed Building Surveyors will need to obtain report and consent from Council before they can issue a permit for buildings or works on affected properties.
We will help with this by providing specific flood level information so that buildings can be appropriately designed to reduce the risk of flash flooding. Flood mitigation advice will typically include advice on:
- where buildings and works should be located away from overland flow paths and
- where and to what extent, living areas need to be raised above flood levels.
We will only grant consent if the owner, builder or developer can demonstrate that they have adequately addressed the flood risk to the property in the design of their buildings or works.