Divers explore magnificent wreck

By DANIEL JACKSON

Three men who risked their lives to explore the Second World War wreck of the Niagara off Northland had so much fun they plan to do it again next year.

This month, divers David Apperley, of Sydney, Tim Cashman, of Wales, and Pete Mesley, of Auckland, braved depths of 120m and the risks of decompression sickness, otherwise known as the bends, for less than one hour exploring the 160m wreck of the ocean liner.

The Niagara was on its way to Suva in June 1940 with 349 passengers and crew, and a secret cargo of 590 gold bars on board, when it hit a German mine and sank between the Mokohinau and Hen and Chicken Islands in the outer Hauraki Gulf.

All the passengers and crew managed to escape, and later salvagers, using a diving bell and grab, managed to raise all but five of the gold bars.

Since the last salvage in 1953, the wreck has lain almost undisturbed, apart from the odd remote survey using scanners or underwater robots, as the depth at which it lies has prevented people from exploring it or retrieving artefacts.

That was until 1999, when Mr Apperley and Mr Cashman became the first to successfully scuba dive on to the wreck, using a complicated arrangement of equipment and breathing gases.

This month, they were reunited to spend three weeks trying to dive on the wreck, this time joined by Mr Mesley, to help make a documentary about extreme diving for Natural History New Zealand.

The weather was against them and they managed to make only two successful attempts with less than an hour in total on the bottom.

The divers said the wreck was a fantastic dive, well worth the effort and the risk.

"It was teeming with life," Mr Cashman said.

"As we went down the line we were first surrounded by kingfish, then golden snapper.

"The wreck itself is covered in coral and has became an artificial oasis for sea life."

Mr Apperley said the Niagara was lying on its port side and, despite more than 50 years at the bottom of the sea, the steel hull was still largely intact.

Damage from the blasting done by the salvage crew to gain access to the cargo of gold allowed the divers to go inside the wreck.

"We were able to go inside by swimming through a massive hole in the side of the ship," Mr Apperley said.

Most of the wooden superstructure has been swept away, but the divers were able to explore some of the third-class cabins and recover a china cup.

They hope to return to the wreck next February or March to try to recover the ship's bell for the National Maritime Museum and map the remains of the vessel.

"You could spend a lifetime exploring that wreck," Mr Apperley said.

To reach the Niagara they had to use tanks filled with a mixture of helium, nitrogen and oxygen, and wear special suits that kept them dry and protected them from the cold.

The mixture of gases, known as Trimix, has to be carefully calculated to prevent the oxygen from becoming toxic under pressure, and also to prevent the nitrogen from having a narcotic effect on the divers.

Although it took only five minutes for the divers to reach the wreck, they had to spend about 4 1/2 hours rising to the surface so the pressure of the gases in their bodies could slowly return to normal and they could avoid decompression sickness.

"If we had some sort of problem down there and we had to surface in a hurry, we would die," said Mr Mesley.

"But it was awesome."