A police spokesperson said emergency services were notified about the accident, which involved a party of three, about 12:50pm.
One person died as a result, the spokesperson said.
''Police worked with RCCNZ and local pilots to reach the group and safely recover the deceased.''
WorkSafe has confirmed an investigation is under way into the incident.
"We understand the worker was undertaking geotechnical work at the time.
"As an investigation has now been opened we can't provide any further comment."
The Otago Regional Rescue Helicopter was called to Manapouri about 1pm. The callout was logged on the organisation's website as an accident.
However, the log also states the mission was stopped.
Police said they were making further inquiries on behalf of the coroner.
"We are also providing ongoing support to the victim's and their families at this time."
