In addition to enabling better preparation for floods and assisting disaster management activities, the new flood information will be used as the 'flood hazard overlay' in the new planning scheme for Carpentaria Shire, consistent with State Planning Policy requirements. In particular, the flood event with a 1% annual exceedance probability (AEP) (this is a 1% change of occurring in any year) will provide the basis for declaring a 'flood hazard area'. This has two main effects:
- When development requiring a development permit is proposed in these areas, Council will consider how flood risks may need to be managed, especially if it is a type of activity that would be at greater risk in the event of a flood.
- It also triggers the application of certain building assessment provisions (under the Building Act and Building Regulation) dealing with flood - notably, the requirements for habitable flood heights to be above the defined flood level (that is the level equivalent to the 1% AEP flood event).
The 1% AEP flood event has traditionally been used across the state as the most appropriate flood planning level. However, people should remain aware that larger floods can happen. As required by the State Planning Policy, the 1% AEP event used by Council includes allowance for climate change factors.
Outside the flood study area, the new planning scheme will continue to include the 'level 1 flood plain area mapping' generated by the Queensland Reconstruction Authority, as required by the State Planning Policy. This is a very broadly based map and does not represent any known flood event. However, it will not trigger any particular requirements under the planning scheme.