What is a Storm Surge?

A storm surge is a rapid rise in sea level generated by the low atmospheric pressure and gale force onshore winds experienced during a tropical cyclone.

Storm surges can cause inundation of low-lying coastal areas.  The combination of a storm surge and a normal ocean tide is known as a ‘storm tide’.

The Storm Surge Map shows inundation at 1 Metre, 2 Metres, 4 Metres and 6 Metres above Highest Astronomical Tide.

The different colours (Red, Orange, Yellow and Blue) indicate the separate areas that may be affected depending on the size of the storm surge predictions.  After a cyclone has passed and the threat of a storm surge is evident,  the Burdekin Shire Council will act depending on the advice given from the Bureau of Meteorology as to the predicted height of the expected storm surge (1m, 2m, 4m, 6m) and inundation.  Based on this information residents in those areas may be evacuated.

What is a Storm Tide?

A storm tide is a rise above the tidal water level along a shore that is associated with a tropical cyclone.  Storm tides will be accompanied by gale force winds, with successive waves of seawater rapidly moving across the foreshore.

When a cyclone forms over open waters the strong winds pushing the water, combined with the low atmospheric pressure in the eye of they cyclone cause the level  of the sea to rise, which results in the formation of large waves.

If this happens away from land, the water can escape and move freely away from the building storm.  As the cyclone moves towards land and the depth of the water becomes shallower, the ever-increasing wall of water does not have a chance to flow away.  These waves may inundate land and cause destructive damage to anything in its path.  Trees, building material and other debris may be carried along by the storm tide.  Any evacuation must occur prior to the storm tide event.

Storm Tide Evacuation Zones –
What do they mean?

RED
EVACUATION
ZONE
Indicates areas at  HIGHEST RISK  of flooding from cyclone storm tide
Residents in the Red Zone face the highest risk of flooding from a cyclone storm tide.
The Red Zone includes low-lying coastal areas and areas that may experience storm tide flooding up to approximately 1 metre above HAT.
ORANGE
EVACUATION
ZONE
Indicates areas at  HIGH RISK  of flooding from cyclone storm tide
Residents in the Orange Zone face a high risk of flooding from a cyclone storm tide.
The Orange Zone may experience storm tide flooding up to approximately 2 metres above HAT.
YELLOW
EVACUATION
ZONE
Indicates areas at  MODERATE RISK  of flooding from cyclone storm tide
Residents in the Yellow Zone face a moderate risk of flooding from a cyclone storm tide.
The Yellow Zone may experience storm tide flooding up to approximately 2 to 4 metres above HAT.
BLUE
EVACUATION
ZONE
Indicates areas at  LOW RISK  of flooding from cyclone storm tide
Residents in the Blue Zone face a low risk of flooding from a cyclone storm tide.
The Blue Zone may experience storm tide flooding higher than approximately 4 metres above HAT.

What is HAT?

HAT stands for Highest Astronomical Tide, which is comparable to a king tide.  It is the highest level of water, which can be predicted to occur under any combination of astronomical conditions.  The Bureau of Metrology (BOM) advices regarding storm tide will refer to a height (in meters) above HAT.  Council will use this BOM information to advise which zone may be affected.

Storm Tide Evacuation Zone Maps

The Burdekin Shire Council has prepared these Storm Tide Evacuation maps for Disaster Management and Evacuation planning purposes. You may use these maps to understand your property’s risk of storm tide inundation.

Our Region’s diverse coastal areas feature varying tide ranges and heights at each community. This diversity is reflected in our mapping by the use of progressively coloured zones which reflect risk. The zones are based on local tide fluctuations and information from the Storm Tide Warning locations throughout the area.

Enjoying a tropical lifestyle in north Queensland also means accepting the responsibility to understand your property’s risk of cyclones and storm tide inundation. This is especially the case when living by the sea.

These maps are not designed for development assessment or insurance purposes. If you have enquiries about these maps, please contact the Burdekin Shire Council on (07) 4783 9800.

Interactive Maps

You can view the interactive maps by clicking on the following link.

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How to use the Interactive Storm Tide Evacuation Maps

Printable Maps

You can view the printable maps by clicking on any of the following links:

How to use the printable Storm Tide Evacuation Maps

  • Identify where your residence is on the map.
  • If you are in one of the coloured zones, you may be at risk from storm tide flooding during cyclones.
  • Identify your evacuation route to your pre-determined safer location.
  • During a cyclone event tune into warnings.
  • Authorities will advise which zones need to evacuate.

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