About volcanic activity
Volcanic activity happens when openings in the Earth’s crust allow magma, gases, and ash to escape from below the surface. Volcanic activity can vary widely in intensity and can include ashfall, lava flows, pyroclastic flows, ballistics, lahars, landslides, debris flows, and volcanic gases.
The Bay of Plenty is one of the few regions in Aotearoa at risk from volcanic activity. Our regional volcanic hazards primarily stem from the Taupō Volcanic Zone which marks the southern end of the Tonga–Kermadec–New Zealand active volcanic arc. This zone stretches approximately 300 kilometers in length from Whakaari (White Island) to Mount Ruapehu.
Whaakari/ White Island is currently the most active cone volcano in Aotearoa. Often a volcanic plume over Whaakari can be observed from the mainland in the Bay of Plenty as the volcano emits steam and gas. On occasion, people in the Bay of Plenty may experience a sulphur smell (smells like rotten eggs) or a visible haze if a plume reaches the mainland. Whilst future eruptions are possible at any time and could impact the crater floor and immediate vicinity of the island, significant ashfall affecting the mainland from an eruption of Whaakari remains unlikely. Landslide-generated tsunami could impact the ocean, beaches and low-lying areas of the Bay of Plenty coastline, however these are very rare and impacts are very localised.
Another volcano in our region is Tūhua/ Mayor Island. Tūhua is dormant, meaning it is not currently active or restless, but it could become active and erupt again. Like Whakaari, the biggest impacts would be felt on the island and surrounding ocean. If Tūhua were to become active again, ashfall, gases and tsunami from Tūhua could affect the mainland.
Pro tip!
Are you prepared for volcanic activity?
Familarise yourself with the volcanic areas in the Bay of Plenty. Learn about the volcanoes and where the next eruption could occur. If you live in or near a volcanic area, you may need to evacuate during the next eruption due to the risk of deadly volcanic hazards. You can view the locations of calderas and active volcanoes located in the Bay of Plenty Region on the BayHazards Viewer.
Learn about the types and potential impacts of different volcanic hazards. Volcanic activity can impact people, property, animals and livelihoods in different ways. Many volcanic hazards will only affect an area very close to the volcano. However, volcanic ash fall can be deposited hundreds to thousands of kilometres from its source, making it the hazard most likely to affect the largest area and the greatest number of people.
Ensure you have Personal Protective Equipment (PPE) in your emergency supply kit. Ashfall could keep you stuck home for days. Make sure your emergency supplies include a P2 or N95 dust mask and eye protection. This will help prevent you from breathing in ash however, it doesn’t protect you from breathing in volcanic gases.
Keep informed with the most up to date information. Advice on what you should do will be shared by local authorities. Information on what the volcano is doing and where ashfall could impact will be shared by GeoNet through volcanic activity bulletins.
Evacuate if necessary. Follow official evacuation orders and move to a safer area if directed. You may have to move quickly as eruptions can occur with very little warning. If you are at the coast or on the water and experience unexpected big waves or long or strong shaking, leave the area as soon as possible.
Shelter indoors. Even if you are not in a volcanic evacuation zone, ash and volcanic gases could still reach you depending on the wind direction. If ash starts to fall, stay inside with all windows and doors closed.
Look out for pets. Keep animals away from ash fall and possible hot spots. Wash animals’ paws and fur or skin to prevent them from ingesting or inhaling ash when they groom themselves.
Wait for the all-clear. If you have been evacuated, do not return home until told it is safe to do so by an official source such as emergency management or emergency services as there may still be risk of exposure to ash or gases. If you have been told to shelter at home, stay there until you have been given the all-clear that it is safe to go outside. This will help reduce your exposure to volcanic gas and ash emissions.
Be cautious with drinking water and home-grown food. Ash will usually make drinking water unpalatable (sour, metallic or bitter tasting) before it presents a health risk. You may eat vegetables from the garden but make sure you wash them first.
If you have a roof tank: Only reconnect the tank to the downpipe once rain has washed all the ash from the roof, or it has been cleaned. If the water tastes sour, metallic or bitter tasting, the roof tank water should be replaced.
Don’t drive through ash. Avoid driving in heavy ash fall. Driving will stir up volcanic ash that can clog engines and stall vehicles. Abrasion can damage moving parts, including bearings, brakes, and transmissions.
Clean-up safely. Be cautious with clean-up. Ash is much more abrasive than ordinary house dust. The best cleaning methods to prevent scratching damage are vacuuming and rinsing. Use water sparingly. If you have a visual impairment, wear eyeglasses. Do not wear contact lenses when dealing with ash as it can get trapped under your contacts and can scratch your eyes. Do not dispose of ash into drains as it can cause blockages and be difficult to remove.
Clean up any ash indoors first to protect indoor air quality.
Avoid going outside or driving unless necessary.
Bring pets indoors if you can do so safely.
Keep all windows and doors closed to limit exposure to ash and vog.
Set up a single entry/exit for your home and place damp towels at doorways to help keep from entering inside.
Turn off and cover heating, ventilation and air conditioning (HVAC) systems draw from outside air.
Do not wear contact lenses because trapped ash can scratch your eyes. Wear glasses instead.
If you have to go outside use protective gear such as N95 and P2 masks and eye protection and keep as much of your skin covered as possible. It’s important to note that whilst N95 and P2 face masks provide protection against breathing ash and tiny particles, they do not protect against breathing in gases. You can find more information on volcanic health risks on the Te Whatu Ora, Health New Zealand website.
Minimise ash build-up on roofs, if possible, by cleaning them carefully.
If you collect rainwater, disconnect the tank from the drainage pipes to prevent blockages.
