New Zealand Earthquake Commission (EQC) CEO Ian Simpson will depart at the end of December after six years leading the organisation’s response to the country’s costliest natural disaster.

He joined the commission in March 2010 before a series of devastating earthquakes and aftershocks struck the Canterbury region from September that year.

Chairman Maarten Wevers says Mr Simpson’s leadership was “outstanding” as the EQC confronted its most significant challenges since its establishment in 1945.

“Over the past six years he has led the organisation’s remarkable and unprecedented response to the Canterbury earthquakes,” Sir Maarten said.

“By any standard, the scale of the event, the number and nature of insurance claims lodged and of settlements to customers has been huge.”

Mr Simpson will become CEO at GNS Science, which is New Zealand’s primary organisation for risk assessment. It monitors and plans for events including quakes, landslides, volcanoes and tsunamis, and examines energy, resource and environmental issues.

“Combining the expertise of having managed disaster response with the forward-looking science of natural disaster risk assessment should see GNS further enhance its world-class reputation,” Minister Responsible for the EQC Gerry Brownlee said.

The EQC will shortly begin the search for a new CEO.

The number of jobs at the commission will almost halve from January as work related to the Canterbury quakes enters its final phase.