Content attributed to Powerlink, QLD: www.powerlink.com.au.
Always assume fallen powerlines are live - do not approach them.
If powerlines are blown over or damaged by a cyclone, severe storm or flood water they can be dangerous. If powerlines are touching the ground or closer to the ground due to damage or flood heights, it is important to keep well away. Electricity from powerlines can jump or ‘arc’ through the air and travel to earth through your body, resulting in electrocution.
Powerlines have a statutory exclusion zone which must be maintained at all times. If you are the first person to notice the fallen towers or powerlines, try and keep people away from the area. Explain that until the lines are tested and proven safe by an Electricity Authority they have the potential to injure people because of the electrical hazards.
High voltages (up to as high as 500,000 volts are distributed over the transmission network and can cause flashover (“jump”), to earth which can result in injury or death and damage to equipment, and property.
You can still be exposed to electrical risks even within vehicles or boats. If a fallen powerline lands on an occupied vehicle or boat or gets caught under a vehicle always stay in the vehicle until the lines are proven safe. If it is a life threatening position, such as the car bursts into flames, jump out and land with both feet together, then hop away so that both feet are always together.
After the flood, be aware that towers and poles carrying power lines may have suffered damage and can be dangerous. Stay away from them until they have been proven safe.
Electricity towers and poles may become unstable, fall or cause overhead lines to sag. as a result of flood waters. Sagging overheads lines may still be “live”. Underground cables may become exposed by erosion or damaged. Any of these can pose risk of electrical shock to boats in flood waters and to vehicles and machinery.
Treat all electrical equipment as live until advised otherwise by the electricty authority. Boat users must exercise greater caution when approaching overhead power lines. Boats used in flood conditions may unintentionally come closer to overhead powerlines than in normal conditions. As flood levels change, boat users are urged to look out for any powerlines in particular fallen or sagging powerlines. Maintain a safe distance from powerlines at all times.
Do not steer your boat across powerlines that are in the water. There is risk of entanglement, the possible presence of electricity, and the potential that the powerlines may spring or shoot upwards due to the lines still being under tension.
If your boat is wooden or fibreglass, do not touch the water or metallic parts of the motor when near fallen wires or poles. There is potential that the electricity is still present and may present a further danger. Trees fallen across the power lines could also be “live”. Do not try to pull trees or branches clear. It is not safe to use an oar to push away, lift or move
Only cross under overhead lines where there is plenty of clearance distance between the highest point between the boat and the lines. The acceptable clearance distance depends on the voltage of the overhead line. A general rule of thumb is that you maintain an 8 metres clearance distance. In some circumstances the electricity distributor might approve a reduced clearance down to as low as 2.4 metres. However, this would only be where the network is deemed to be electrically intact and where they have fully assessed other relevant factors.
If you are in a boat and the powerlines fall into or across your boat, do not touch them. Do not get out of the boat as you may be creating an electrical path for the electricity to pass through to ground. Call emergency services on 000.
When driving power vehicles across flooded or water logged areas do not drive your vehicle across the fallen lines. If powerlines have fallen across or become entangled in your vehicle, remain inside your vehicle and call for help. If you are in immediate danger, (i.e. the wires are crackling or moving, or your vehicle is on fire), open the door and jump clear keeping your hands off the vehicle and both your feet together, and hop away until at least 10 metres away from your vehicle. Warn everyone to stay away from vehicles where power lines may have fallen across the vehicle.