MBRC Planning Scheme - Dwelling houses in Flood hazard overlay areas
The Flood hazard overlay map plays a role in shaping a property's development. Development includes:
- building or extending
- a change of use
- subdividing
- clearing vegetation
- filling or excavation.
If your property is within the mapped area, you may be limited on what you can build or modify.
Our Flood hazard overlay map and code
The overlay map and code aim to protect people and property from flooding.
The map shows areas affected by flooding that are a risk to people and property. It includes three flood planning areas:
- High risk flood hazard area
- Medium risk flood hazard area
- Balance flood planning area.
Find out more about Flood hazard overlays.
The overlay code outlines the requirements for development in these areas based on their level of risk.
Find more information in section 8.2.2 of the planning scheme.
Resources for checking if a property is in a Flood hazard overlay
There are 3 free online tools you can use to get property-specific information.
- To see what overlays affect a property, download a my property look up report. If there is no reference to the Flood hazard overlay, then it does not apply to the property.
- To check for flood information relevant to the Flood hazard overlay, download a flood check development report. These reports also include information on defined flood events and flood planning levels.
- To view the Flood hazard overlay, use the planning scheme interactive map.
You can also see new flood data that applies to properties with a flood check property report.
Dwelling houses in Medium and High risk flood hazard areas
If you plan to build a new dwelling house or extend existing ones by more than 50 square metres in Medium and High risk flood hazard areas, you will need development approval from Council. This includes domestic outbuildings and secondary dwellings.
To apply for approval, you will need to complete an assessable (code assessment) application. Your application will need to show how the proposed work is designed to reduce the risks of the flood hazard under the Flood hazard overlay code. This could include:
- building to the minimum habitable floor level
- using piers and poles to achieve the minimum habitable floor level
- undertaking structural design using a qualified engineer
- ensuring the building work can withstand any hazard it may be exposed to
- using waterproof materials for non-habitable areas below the minimum habitable floor level
- ensuring fencing is at least 50% permeable
- ensuring building design addresses the street
- demonstrating that the works won't cause flooding to other properties.
Filling is not permitted in High risk and Medium risk areas except for the creation of stormwater infrastructure such as detention basins, bioretention and levees. For more information, refer to the performance outcomes and fill requirements of the Flood hazard overlay code.
New dwelling houses cannot be built within a Limited development zone. If you wish to extend an existing dwelling in a High risk flood hazard area in this zone, you’ll need to submit an impact assessable development application. This applies regardless of the extension's size.
Development in Medium and High risk areas must also follow the Queensland Development Code MP3.5 Construction of buildings in flood hazard areas.
Dwelling houses in the Balance flood planning area
If your property is in the Balance flood planning area (outside the High and Medium risk flood hazard areas), building a new dwelling house or extending an existing one will be considered accepted development, but may be subject to additional requirements.
Extending an existing dwelling by 50 square metres or less is considered accepted development without additional requirements. This means there are no planning scheme requirements if the building work meets the conditions outlined in the Accepted development table 1.7.7.1 of the planning scheme.
However, building a new dwelling or extending an existing one by more than 50 square metres (including outbuildings and secondary dwellings) in the Balance flood planning area must follow the requirements of the Flood hazard overlay code. This includes:
- building to the minimum habitable floor level
- using waterproof materials in non-habitable areas (such as garages and sheds) that are below the minimum habitable floor level
- ensuring that filling doesn't block water flow or impact other properties during the Defined Flood Event. Filling is allowed in the Balance coastal planning area, at a minimum to the Flood planning level.
- storing hazardous chemicals, such as fuel or paint, at or above the minimum habitable floor level.
For more information, refer to RAD2 to RAD6 of the Flood hazard overlay code in the planning Scheme.
If these requirements are not met, you will need development approval from Council.
Dwelling houses in Drainage Investigation Areas
The Flood hazard overlay code identifies Drainage Investigation Areas. My property lookup also identifies if a property is in a Drainage Investigation Area.
These areas identify where further development may be possible. However, it is subject to investigations confirming building design, earthworks, drainage and infrastructure solutions that can reduce the impact of floods.
Council approval is needed to build a new dwelling house or extend an existing one by more than 50 square metres in these areas. This includes secondary dwellings and domestic outbuildings. To apply for approval, you will need to complete an assessable (code assessment) application. The application needs to show compliance with the relevant requirements for part of the High or Medium risk flood hazard area. This is in which the dwelling house or extension is being placed.
Building or extending a dwelling house does not trigger the need to prepare a drainage plan for the area. All other forms of development in these areas will trigger an impact assessable application and the need to prepare a drainage plan.
Minimum habitable floor heights
Minimum habitable floor heights are located, designed and constructed to:
- 300 millimetres above the defined flood event level for sites east of the Bruce Highway and outside the Erosion Prone Area Overlay
- 500 millimetres above the defined flood event level for sites east of the Bruce Highway and inside the Erosion Prone Area Overlay
- 750 millimetres above the defined flood event level for all sites west of the Bruce Highway.
For a definition of habitable floor level, refer to Schedule 1, table SC1.2.2 of the planning scheme. The Defined Flood Level is the event used to determine the flood level for planning and development purposes.