Lake Hāwea is busy in summer — with families on the beach, swimmers, paddleboarders, kayakers, and boats out on the water. This page covers what to do if a major earthquake happens while you are at the lake.
The hazard at the lake is different from the hazard elsewhere. In a major earthquake, landslides into Lake Hāwea can generate large waves — referred to in Civil Defence terminology as lake tsunamis. After the initial wave, the lake may continue oscillating dangerously for hours — a phenomenon scientists call a seiche.
There is no warning system for any of this. By the time you can see a wave, there is no time to move. The advice below is for everyone — residents, visitors, and anyone passing through.
For residents of John Creek (the most exposed lakeside settlement), see the John Creek — Warnings page for daily-life planning.
This applies to anyone at any Lake Hāwea beach — Scotts Beach, the Esplanade Reserve, Gladstone Beach, the boat ramp, John Creek, or anywhere along the shoreline.
During the shaking:
- Drop, Cover, Hold On. Even outdoors, drop low to the ground, cover your head and neck with your arms, and wait for the shaking to stop. Do not try to run while the ground is moving — you are more likely to fall and be injured.
As soon as the shaking stops:
Get everyone out of the water immediately, including children
Account for everyone in your group before moving
Move uphill, away from the lake edge, as fast as you can
Take only what you can carry quickly — do not wait to pack up gear
Do not stop to take photos or watch the lake — the water may look normal until a wave is too close to escape
Aim to be on higher ground within five minutes
If you can see the lake from where you are, you are not high enough.
This applies whether you are in a boat, on a paddleboard, kayaking, or swimming.
During the shaking: - Stay where you are if you are in deep open water. A boat or board in deep water will ride over a wave as a swell. The danger is in the shallows where the wave breaks.
Hold on. The water itself may shake or churn during the earthquake.
As soon as the shaking stops:
Do not head for shore. The shoreline is the most dangerous place to be after an earthquake at the lake.
Stay in open water away from cliffs, steep slopes, and any visible signs of landsliding
Help anyone in the water get into a boat or onto a stable platform if you can
Wait for at least an hour before approaching shore, and then approach cautiously
Watch for debris in the water — fallen trees, structures, or material from landslides
Boats and paddlecraft already at the shoreline when shaking starts should follow the beach advice — get out of the water, get to higher ground.
The lake may continue moving dangerously for hours after the initial wave. Aftershocks can also trigger further landslides. Do not return to the lake edge until:
At least several hours have passed without significant aftershocks
The lake surface has been calm for an extended period
Information from the Hāwea CRG, Otago Gets Ready, or Civil Defence Otago confirms it is safe
Even then, treat the lake edge with caution for the first day or two. Damaged property and unstable shoreline may be hazardous.
Most visitors to Lake Hāwea do not know about the lake-tsunami hazard. The risk is specific to lakes in seismically active regions and is not part of the standard tourism information.
If you have visitors staying with you, or you rent out a property near the lake:
Tell guests what to do if shaking starts at the lake
Mention it the same way you would mention sun safety or rip currents
Consider a printed sheet on the fridge or noticeboard with the key information
A few seconds of explanation could make the difference between a good response and a tragedy.
Identify Your Risks — the wider context of natural hazards in Hāwea
During An Earthquake — the standard Drop, Cover, Hold On response and other situations
John Creek — Warnings — for residents of the most exposed lakeside settlement
Last reviewed: May 2026.