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Flood planning level maps

The flood planning level maps identify hazard areas around the Gold Coast that are subject to flood.

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Flood planning level maps

The flood planning level maps identify hazard areas that are subject to flood, with the map accessed via the City Plan Interactive Mapping tool.

If you are developing on land that is identified within the flood planning level map, you will need to undertake further assessment by reviewing the necessary provisions in the flood overlay code. For more information on development applications, refer to the before lodging a development application page.

For instruction on how to use the City Plan Interactive Mapping refer to how to use the City Plan.

Please note: Even if you are or are not within the hazard areas that are subject to flood, this does not mean you will or will not be impacted by flooding.

Updated flood planning level mapping

The City’s updated flood planning level mapping commenced as part of City Plan Version 6 on 20 September 2018.

The updated mapping considers future changes to climate, incorporating the projected increase in sea level of 0.8 metres above present day levels by 2100 established by the State Government in 2015.

The updated mapping also includes the State Governments projected 10 per cent storm tide intensity and 10 per cent rainfall intensity, based on advice from industry representatives.

Find out more about the updated mapping.

Further information

Find Frequently Asked Questions about flood planning level mapping below.

Related information

Jump to key information
  • What is flood planning level mapping?

    Flood planning level mapping identifies which properties may be affected by a designated flood event and acts as a trigger for development assessment.

    The maps reflect the impact of a rain event that has one per cent chance of occurrence in any given year (one per cent AEP) coinciding with a storm-tide for the majority of areas. These maps by themselves do not show flood risk in its totality with areas outside of the flood map not necessarily immune from flooding. Infrequent or local floods can affect any property.

  • What are flood planning levels?

    Flood planning levels are obtained from the City’s flood search system. Properties should be built above flood planning levels.

  • What are flood models?

    Flood models are used to inform and refine the flood map. A flood model is a computer simulation of a river or floodplain system to determine the magnitude, extent and depth of flooding; how fast floodwaters rise; and the implications for flood damage and emergency planning.

  • Why have flood levels changed?

    The maps were developed utilising a more robust software platform, up-to-date flood related topographic, land use, technological and hydrological data.

    The updated mapping considers:

    • Future changes to climate, incorporating the projected increase in sea level of 0.8 metres above present day levels by 2100 established by the State Government in 2015.
    • State Government projected 10 per cent increase in storm tide intensity by year 2100. Storm tide intensity is an indicator of the power of the cyclone.
    • An increase of 10 per cent in rainfall intensity, based on advice from industry representatives. Rainfall intensity is the measure of the amount of rain that falls within a unit of time.
    • Vast areas of the city were void of flood information in the past due to lack of predictive models or historical information. The City is now in possession of new models that cover large sections of the city. Therefore, there are properties that did not have any flood information in the past and now they have relevant flood information to the property, as reflected in the City Plan Flood overlay map.
    • The City’s old flood map was informed solely by historical flood data for some areas. This data reflected a flood level with an unknown return period. We now model for these areas and have generated flood levels that have one (1) per cent chance of occurrence in any given year. As a result flood information for some properties is now more accurate.
  • I was affected by the recent flood but my property is not shown as being affected on the new mapping?

    1. City Plan flood maps are based on a rain event that has one per cent change of occurrence in a given year. There is always a possibility of having rarer rainfalls that may overwhelm our protection measures.
    2. There may be small creeks on higher grounds that are not fully included in our models yet. These creeks may experience flash flooding, causing short term overland flooding.
    3. Blockages to drainage systems and restrictions to the flow of water in waterways can result in flooding.
    4. A property may be on an overland flow path which is yet to be included in the City Plan Flood Planning Level Map.

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