Storm surges—being prepared and staying safe
A storm surge is a raised dome of sea water typically 60km to 80km across and 2–5m above the normal sea level. They are caused by strong winds and areas of low pressure created by a cyclone or severe storm.
As the storm reaches the coast, huge winds whip up the sea and push the storm surge over low-lying coastal areas.
Storm surges can move inland quite quickly, damaging buildings and cutting off escape routes. There is a high risk of drowning.
A storm surge is not the same as a tsunami, or tidal wave. A storm surge comes in like a rapidly rising tide, but it can be extremely dangerous and destructive.
The height of the storm surge will depend on:
- the intensity of the storm—the stronger the winds the higher the surge
- the angle at which the storm crosses the coast—a right-angle crossing will increase the surge
- the shape of the sea floor—the more gentle the slope, the greater the surge
- local features such as bays, headlands or islands can funnel the surge and amplify its height
- existing tidal conditions—if the cyclone crosses the coast at high tide, the flooding will be at its worst.
Preparing for a storm surge
There are some simple things that you and your family can do to stay safe and protect your property.
When a severe storm surge seems likely...
- Listen to your local radio station for warnings and advice. Don't use your phone unless it is essential.
- Prepare to move vehicles, outdoor equipment, garbage, chemicals and poisons to higher locations.
- Decide which indoor items you will raise (e.g. furniture, clothing) or empty (refrigerators, freezers etc.) if your home may be flooded.
- Check your emergency kit and consider what you will do with your pets.
If you need to evacuate...
- If you decide to leave of your own accord, make sure you tell the police or your local State Emergency Service and your neighbours.
- Make sure you pack warm clothing, essential medication, valuables, personal papers, photos and valuables in waterproof bags, to be taken with your emergency kit.
- Raise your furniture, clothing and valuables onto beds and tables and into the roof space (place electrical items as high as possible).
- Empty and turn off refrigerators and freezers, leaving the doors open to help prevent them floating about.
- Turn off the power, water and gas and remember to take your mobile phone.
- Put sandbags in toilet bowls and over all laundry/bathroom drain-holes to prevent sewage back-flow.
- Lock your home (remembering to take your keys) and take the recommended evacuation routes for your area.
- Don't drive into water of unknown depth and current.