The Police Dive Squad has returned to Lake Alta in the Remarkables mountain range for its annual ice‑diving training, working in some of the most challenging conditions in the country.

The remote alpine lake sits above Queenstown and can shift from clear skies to whiteout conditions within minutes.

Access to the site required either a helicopter or a snow groomer to transport diving equipment, shelter materials and, for the first time, Starlink, to support critical communication.

Senior Constable Carl O’Donnell, Wellington-based launch crew and top‑side support, said poor weather initially prevented the helicopter from reaching the lake.

Braving the windchill for a team photo. Photo / supplied

“We loaded everything onto a snow groomer – scaffold, dive gear, the lot,” O’Donnell said.

He said supporting the team was a privilege, with duties ranging from logistics to morale.

“One of my key support roles was making a warming cup of tea as the windchill at Lake Alta dipped to -15C.”

The tether lines include a hard-wired comms link. Photo / supplied

This year’s multi‑day training involved police, the Royal New Zealand Air Force and the Royal New Zealand Navy, strengthening diving capability, logistics, safety planning and interagency coordination.

Six staff completed their first-ever ice dives, gaining experience that cannot be replicated in other environments.

Safety remained the top priority, with lessons from previous years informing better setups to prevent gear freezing and shelters lifting in high winds.

This dive was described as surreal and offered crystal-clear views with an overwhelming sense of calm beneath the ice. Photo / supplied

Senior Sergeant Bruce “Bad” Adams, officer in charge of the National Dive Squad, said the conditions demanded robust systems and contingency planning.

“You can’t just dive and hope for the best.

“You need systems, back‑ups and a plan for when things go wrong.”

Senior Sergeant Bruce (Bad) Adams, Constable Amy Love and Senior Constable Carl O'Donnell on location. Photo / supplied

He said this year’s ice conditions were particularly severe, with a one‑metre-thick layer that included 600mm of hard ice.

A chainsaw was unable to cut through the ice completely, requiring the team to finish the job with chippers.

Beneath the surface, divers experienced conditions unlike typical police operations, which often involve murky water and low visibility.

“It’s like stepping into another world – you go from chaos and wind in the shelter to complete silence,” Adams said.

The Police Dive Squad went to Lake Alta in the Remarkables mountain range above Queenstown to train. Photo / supplied

First‑time ice diver Constable Amy Love said the experience was both freezing and unforgettable.

“Once you’re under the ice, it’s just silence.

“Very eerie, but peaceful.”

Cold exposure varied between divers, with some losing dexterity within minutes and others managing longer in the freezing temperatures.

Under the ice, silence and wonder await. Photo / supplied

Clear communication was essential to reduce the risk of hypothermia and ensure safe operations.

The systems developed during the exercise can be applied to other hazardous environments, including effluent ponds and thermal or acidic pools.

Police worked closely with the Department of Conservation and staff at the Remarkables ski field to minimise environmental impact.

Although the ski field had closed for the season, the remote location still saw the occasional day‑tripper.

Police said the exercise demonstrated the diversity of roles within the organisation and the unique opportunities available to staff.

-Police Ten One Magazine