New Zealand at risk of tsunamis from lakes - research

Morning Talk 15/06/2018
Lake Wakatipu. Image: Getty.

New research suggests that New Zealanders are potentially at risk from tsunamis coming from lakes as well as the ocean.

The research, published by the Geological Society of London, shows large lakes in New Zealand are at risk.

The lakes at risk included Lake Wakatipu and Lake Wanaka in the South Island, and Lake Taupo in the North Island. 

NIWA marine biologist Joshu Mountjoy has been studying Lake Tekapo in the South Island and discovered it could generate tsunamis more than five metres high. He joined Mark Sainsbury on Morning Talk.

A lot of New Zealand lakes are in steep environments, and are subject to active tectonics, earthquakes, volcanoes, but Dr Mountjoy has been focused his research on landslides.

There are two types of landslides, those that happen underneath the water and those that happen when a rock avalanche or a landslide comes into the lake.

Dr Mountjoy says that a large rock falling into a lake has the same effect of pushing your hand suddenly into a bath of water.

“The surface of the water draws down to sort of follow the movement… then it bounces back up and waves move away," he told RadioLIVE. 

Although the likelihood of a tsunami isn’t high, Dr Mountjoy recommends treating a lake the same as the coast in the case of a natural emergency.

“As at the coast line, if you feel a really strong earthquake and it goes on for more than a minute or it’s so strong that you can’t stand up, move away from the lakeshore.”

Listen to the full interview with Dr Joshu Mountjoy above.

Morning Talk with Mark Sainsbury, 9am - 12pm Weekdays and streaming live on 'rova' channel 9 - available on Android and iPhone.