FAQs
A flood overlay is a map in the Planning Scheme that shows where land is at risk of flooding. The map corresponds to the relevant planning provisions in the Planning Scheme.
There are three overlays that can be applied to flood prone land including the Floodway Overlay (FO), Land Subject to Inundation Overlay (LSIO) and Special Building Overlay (SBO).
The flood overlays are specifically designed to identify land with particular flood characteristics and ensure that the use and development of flood prone land is designed and managed based on the level of flood risk through the planning permit process.
Flood overlays are a means of identifying land at risk of flooding.
They provide a trigger for the Catchment Management Authority and the Planning Authority to ensure development is designed to minimise the risk to life and property.
Where a proposed development does not expose people to an unacceptable hazard or does not make flooding worse elsewhere, it may be permitted subject to conditions.
Some buildings and works can be exempted from requiring a planning permit and these are outlined in the Planning Scheme.
The property market determines the value of any residential property. Property owners should seek their own valuation advice if they are concerned that flood risk may influence their property value.
Flood overlays do not stop development. They provide a trigger for the Catchment Management Authority and the Planning Authority to ensure development is designed to minimise the risk to life and property.
Where a proposed development does not expose people to an unacceptable hazard or does not make flooding worse elsewhere, it may be permitted subject to conditions. Some buildings and works can be exempted from requiring a planning permit and these are detailed in the Schedules to the Floodway Overlay (FO) and Land Subject to Inundation Overlay (LSIO) and the Special Building Overlay (SBO). These schedules are to be included in the planning scheme amendment.
The insurance industry has developed its own database of flood risk for individual properties, the National Flood Information Database (NFID), which has regard for both depth and frequency of flooding. This national flood database is based on the most up-to-date flood studies, rather than flood overlays.
The City of Ballarat is obliged by state policy to develop integrated long-term plans for the sustainable development and wellbeing of their communities, as well as ensure policies and controls for land use remain current in the Ballarat Planning Scheme.
The City of Ballarat Council Plan 2025-2029 and Ballarat Strategy 2040 identifies a need to better understand the effects of flooding and introduce planning controls to enable authorities, residents and businesses to understand and manage flood risk.
Identifying flood risks will minimise the impacts of flooding on the community through accurate emergency response plans based on current data, improved planning and development decisions and assist in prioritising where infrastructure improvements and flood mitigation should occur.
There are 11 waterways that are part of this project, with some tributaries (streams flowing from waterways) counted as one.
The waterways included are:
- Yarrowee River
- Gnarr Creek
- Canadian Creek and tributaries
- Bonshaw Creek
- Redan Creek
- Kensington Creek
- Chase Waterway
- Little Bendigo Creek
- Hit or Miss Gully
- Warrenheip Creek
- Ryans Drain.
Flood risk can be managed in different ways.
Mitigation measures provide a means to reduce the existing flood risk by lowering the likelihood of flooding and/or lowering the flood damages (consequences) for a given flood depth. Mitigation measures can be broken into:
Structural: Physical barriers or works designed to prevent flooding up to a specific design flood standard. Structural measures aim to reduce existing flood risk by reducing the likelihood of flooding at given locations. Structural works include levees, floodways, waterway works or improvements to hydraulic structures.
Non-structural: Management and planning arrangements between relevant authorities designed to reduce flood related damages. Non-structural measures aim to reduce existing flood risk by lowering the potential for flood damage. Non-structural measures include land use planning, flood warning, flood response and flood awareness.
This flood project only considers non structural mitigation measures, however these will be used to inform structural mitigation measures
Yes. Flood Intelligence Reports are being prepared to support the project. These reports identify flood depths and extents including where flood water crosses roadways, inundates special buildings such as emergency services, schools, and floodway velocities.
This information will provide a clearer picture of the extent of mitigation required to reduce inundation. The reports will also allow the City of Ballarat to plan drainage works in the areas that require mitigation.
Flood events are described as an annual percentage likelihood (Annual Exceedance Probability – AEP). For example, a 1 per cent AEP event would have a one per cent likelihood of occurring in any given year, this would be the same as once in a 100-year period.
How flood estimation is done is determined by national guidelines called the Australian Rainfall and Runoff – A Guide to Flood Estimation published by the Australian Government and the peak body for engineers in Australia called Engineers Australia. Projected temperature increases that generate changes in rainfall patterns and volumes are factored into the flood modelling methodology as standard practice.
In response to submissions received during the community consultation period, the flood models for Redan Creek and Canadian Creek and Tributaries were adjusted. The completed Ballarat 11 Waterways Flood Study and Modelling is available to view via MySay.
There are several waterways, including defined waters, drains and gullies not included in the project.
The Winter Creek was not included due to its location on the municipality's outskirts. At the time the project was initiated, the creek did not directly impact any densely populated areas or areas identified for future development. However, planned growth in Ballarat West Urban Growth Zone has prompted the modelling of the Winter Creek, which is underway now. Given timing the modelling for Winter Creek is not included in this project, as it relates to any proposed planning scheme amendment.
The Union Jack Creek was not included at the time the project was initiated, however has been identified for modelling due to potential flood impacts within the township of Buninyong. This modelling is currently underway, however again due to timing is not included in this project, as it relates to any proposed planning scheme amendment.
Burrumbeet catchment, including Miners Rest township, is not included, as it currently has flood overlays. These overlays are due to be updated and flood modelling is underway and planned for completion in the next financial year.
The Ballarat 11 Waterways Flood Study is now completed and the Planning Scheme Amendment process underway.
Ballarat Council adopted the Ballarat 11 Waterways Flood Study 2025 and the proposed planning scheme amendment documentation at their December 2025 Planning Delegated Committee Meeting and decided to seek authorisation from the Minister to start a planning scheme amendment to implement the flood overlay mapping into the Ballarat Planning Scheme.
The Minister authorised the City of Ballarat to pursue a Planning Scheme Amendment in February 2026.
The Planning Scheme Amendment is now on exhibition and the community can make formal submissions between 27 April and 29 May 2026.
