Natural Hazard and Risks

Piopiotahi Milford Sound is located at the southern end of the Alpine Fault, a significant geological feature which runs approximately 800km up the spine of the South Island of New Zealand. While this fault is fascinating, it is active, with a history of generating major earthquakes occurring approximately every 300 years (scientific evidence indicates the last one was in 1717 AD). To learn more about the science and New Zealand’s response planning, check out the AF8 website.

In the event of a strong earthquake, there’s a possibility of landslides and localised tsunamis which could affect critical infrastructure in Piopiotahi Milford Sound, including key access roads.

Key actions to take in an earthquake:

• Drop, Cover and Hold. Drop down on your hands and knees. Cover your head and neck. Hold on to your shelter.

• If an earthquake is Long or Strong, Get Gone. Move immediately to the nearest high ground or as far inland as possible. Don’t wait for an official tsunami warning.

Piopiotahi Milford Sound can experience tsunamis from both local and distant sources, especially following a large earthquake. If a landslide occurs into the fiord, it may generate a tsunami that could reach significant heights and would pose a significant risk to people at Milford Sound. Since many visitors enjoy the area daily, it’s crucial to be aware that the first warning of a tsunami could be the onset of an earthquake with little time to respond.

If you are near a shore and experience any of the following, take action. Do not wait for official warnings.

• Feel a strong earthquake that makes it hard to stand or a long earthquake that lasts more than a minute

• See a sudden rise or fall in sea level

• Hear loud or unusual noises from the sea

Key actions to take in an earthquake:

• Drop, Cover and Hold. Drop down on your hands and knees. Cover your head and neck. Hold on to your shelter.

• If an earthquake is Long or Strong, Get Gone. Move immediately to the nearest high ground or as far inland as possible. Don’t wait for an official tsunami warning.

While Fiordland is known for its rainfall, wildfire is still a risk and can happen any time of year. Open fires are prohibited in the Fiordland National Park for this reason.

At campsites, only use the designated fire/ash disposal areas. If you’re a smoker, please dispose of cigarette butts safely and double-check they’re out. Practice good fire safety and remember, the smallest spark can cause a fire.

Wildfires move quickly, so quick actions make all the difference.

Key action to take in a wildfire:

• If in doubt, get out! If you can see smoke or flames from a wildfire and you feel unsafe, don’t wait for an official warning to leave. Evacuate immediately.  Call 111 to report it to the Fire Emergency Service, especially if your life or property is threatened, or you can’t evacuate on your own.

Storms can happen any time of the year and can bring strong winds, heavy rain or snow, thunder, lightning, and rough seas.

Met Service is New Zealand’s national weather authority and the go-to source for land-based, coastal, recreation, and high seas information.  It also issues severe weather alerts using a system of Warnings and Watches and Severe Weather Outlooks. Outlooks and Watches are a heads-up to stay alert for potential bad weather across New Zealand and keep an eye on the forecast for updates. Make sure you check out the Southland-specific part of the website well before you visit and familiarise yourself with the warning system.

Orange warnings are issued when bad weather is expected to meet Severe Weather Criteria. This could be heavy rain, strong wind or heavy snow. Be prepared and take action as appropriate – there could be some disruption to your day and potential risk to people, animals and property.

Red warnings are issued for extreme weather events that are likely to have significant impact and disruption like heavy rain/snow, strong winds or cyclones.

A Red Warning is Act Now – immediate action is needed to protect people, animals and property. Be prepared to follow the advice of official authorities and emergency services.

Piopiotahi Milford Sound is known for its stunning scenery and heavy rainfall, averaging over 7 meters a year. Sometimes rainfall can accumulate rapidly, causing flooding and leading to road closures. While our infrastructure is built to be resilient in most weather, extreme conditions may occasionally isolate the area.

Key actions to take for flooding:

• Act quickly if you see rising water. Do not wait for official warnings. Head for higher ground and stay away from floodwater.

• Stay out of flood water. Never try to walk, swim or drive through flood water.

• Make sure you wash your hands, clothes and property after contact with flood waters. Always assume that flood water is contaminated with farm run-off, chemicals and sewage. Contaminated flood water can make you sick.

Regular severe weather can lead to landslides, particularly in coastal regions with limited topsoil. These are a natural part of the landscape, and while we’re equipped to manage them, they can still occur.

A strong earthquake on the Alpine Fault (see Earthquakes section) could also trigger a landslide-generated tsunami in Piopiotahi Milford Sound.

During winter and spring, snow and avalanches are another consideration on the alpine highway into the Piopiotahi Milford Sound area.

The Milford Road Alliance operates an internationally recognised specialist avalanche control programme that monitors the road and surrounding mountains around the clock to maximise safety and minimise road closures.

Key action to take: Always check the latest Milford Road information and follow instructions. This is particularly important between May and November as the road may be closed or vehicles may need to carry/fit snow chains.

Guests should be aware that our campsites are beneath native rainforest and therefore pose some risk to campers. These risks may include:

• Falling branches or trees - High winds or storms can increase this risk, potentially causing damage to the vehicle or injury to occupants. This risk is partially mitigated by Milford Sound Lodge undertaking periodic Tree Risk Assessments using professional arborists to assist in managing the forest and associated risk.

• Debris damage: Trees can shed leaves, branches, and other debris, which may fall onto the campervan and cause damage. This could include scratches, dents, or broken windows if the debris is large enough.

• Sap and resin: Parking under certain types of trees can expose the campervan to sap and resin, which may be difficult to remove and can damage the vehicle's exterior or paint finish.

• Wildlife encounters: Camping under trees may attract wildlife such as birds, or insects, which could potentially cause damage to the campervan or be a nuisance to occupants.

• Limited sunlight for solar panels: If your campervan relies on solar panels for power, parking under dense tree cover may limit the amount of sunlight the panels receive, reducing their effectiveness in charging the vehicle's batteries.