New research highlights potential danger of Lake Wānaka tsunami

The results of a seismic mapping project on the bed of Lake Wānaka have raised concerns a lake tsunami could potentially one day impact the township.

Seismic mapping on Lake Wānaka. Source: Supplied

It comes after the project provided new evidence of a likely active fault that was first identified in 2019.

The work was undertaken by NIWA and GNS scientists after being commissioned by the Otago Regional Council.

In a statement released today, the council says the goal of the seismic survey was to find more conclusive evidence of the proposed fault so that the community can better prepare for the effects of a potential earthquake.

The council's manager of natural hazards, Jean-Luc Payan, said the work highlighted the lake tsunami risk presented by faults under Otago’s lakes.

“This research has improved our understanding of the natural hazard risks faced by the Wanaka township.

“While the research is not conclusive, the results of the lakebed mapping provide further supporting evidence of the presence of an active fault beneath Lake Wānaka.

“This raises the possibility, in the event of an earthquake, that a lake tsunami could be among the hazards faced by the township.

“It’s an important reminder of the tsunami risk associated with earthquakes, not just in coastal areas but inland around alpine lakes as well,” Payan said.

The full NIWA report can be found here.

Otago Regional Council says it's planning a range of work over the coming years around lake tsunamis in Otago.