The wreck of the Rena in historical context

Containers falling off the Rena

On 5 October 2011 the Mediterranean Shipping Ccompany-chartered, Liberian-flagged container ship Rena astonished local mariners by grounding on the clearly marked Astrolabe Reef in the Bay of Plenty while approaching Tauranga Harbour.

At the time of writing, salvage of the ship's containers is about to get underway. Most of the oil has been pumped off, but some oil and containers went in the sea, seabirds have been harmed, the master and another officer have been arrested and a small fleet of salvage ships is attending to the badly damaged ship. History is in the making ...

New Zealand’s biggest shipwreck?

The Rena is the largest ship ever lost in New Zealand waters. The Rena, built in 1990 as the Zim America, is 37,209 tons gross registered tonnage, and 47,000 tonnes deadweight (i.e., what it can carry). The ship is 236 metres long.

The largest ship lost here until now was the Soviet cruise ship Mikhail Lermontov. The Lermontov sank in Port Gore in the Marlborough Sounds on 16 February 1986 after striking rocks while leaving Queen Charlotte Sound. The Mikhail Lermontov, built in 1972, was 22,352 tons gross and was 155 metres long. One man died, though several recreational divers have died since then while exploring the wreck.

The next largest ship lost in local waters was the Canadian-Australasian Line passenger liner Niagara, sunk off Mokohinau Island by a German-laid mine on 19 June 1940. The ship, built in 1913, was 13,415 tons gross.

New Zealand ’s costliest shipwreck?

In the terms of what matters most, human lives, fortunately, no. The biggest death toll in our history came with the wreck of HMS Orpheus on the Manukau bar on 7 February 1861. That cost the lives of 189 of the 250 officers and men aboard the ship that day.

But in terms of financial and ecological cost, that is about to change.

New Zealand’s worst environmental maritime disaster?

On 13 October the New Zealand Herald reported Environment Minister Nick Smith as describing the Rena stranding as New Zealand’s ‘worst maritime environmental disaster’.

The same day – and with more to come – Radio New Zealand reported Director of Maritime New Zealand, Catherine Taylor, as saying that on a scale of 10, ‘the disaster rates an eight’.

The loss of the oil tanker Torrey Canyon off the British coast in the 1960s changed people’s attitude to marine pollution.

In the days of sail there was no fossil fuel to come ashore. Steam took over, but those ships burned coal. When they sank off the coast the coal sank with them (and the little that was washed ashore sometimes provided beachcombers with welcome free fuel).

That changed with the switch from coal to oil firing, and more particularly the more recent use of low-grade ‘bunker fuel’ by big ships. It is much thicker and more toxic than the sort of marine diesel a boatie may accidentally spill when topping up at a marina.

And, of course, ships have got a lot bigger. When big ships get into trouble, they can spill a lot more fuel and cargo than their predecessors did.

So how bad is this? It is still developing, but on 12 October the New Zealand Herald reported that the Maritime New Zealand website gave some comparisons – these were the previous ‘more significant marine oil spills in New Zealand waters since 1990’.

Don Wong 1998 

The Korean fishing vessel Don Wong 529 ran aground off Stewart Island, spilling 400 tonnes of automotive oil into the ocean. Of the oil spilled, 310 tonnes was dispersed either naturally or with chemicals. The other 90 tonnes was recovered by salvors.

Rotoma 1999

The container ship Rotoma discharged around 7 tonnes of oily water off the Tutukaka coast, creating an oil slick 6 km long. The ship’s owner and agent each admitted charges of discharging petroleum and failing to notify the spill, and were fined a total of $60,000.

Seafresh 1 2000 

In 2000, the vessel Seafresh 1 sunk off the Chatham Islands, after catching fire. Divers managed to plug vents on the wreck, and of the 102 tonnes of diesel on-board, only 60 tonnes spilled. No harm to wildlife on the shoreline was observed.

Jody F Millennium 2002 

In 2002, huge swells caused the log ship Jody F Millennium to break its moorings in Gisborne Harbour. While being shepherded to safety out at sea, a big wave drove the ship onto a beach, where it remained stranded for 18 days. The Jody F leaked 25 tonnes of heavy fuel oil into Poverty Bay, affecting an area of about 8 km of coastline from Tuahine Point to 300 metres along the coast, about opposite the airport.

Are these accidents getting more common?

Fortunately, no.

Apart from the Mikhail Lermontov, only three large overseas ships have come ashore in New Zealand in the last 30 years. All three bulk carriers, the Pacific Charger (Wellington 1981), Jody F Millennium (Gisborne 2002) and the Tai Ping (Bluff 2002) were successfully refloated.

Better charts, radar and now GPS have made our coasts much safer than in colonial days when passengers and crews could die in their hundreds.

Read more:

• Maritime New Zealand incident pages  - including an excellent gallery
• Rena in focus - daily coverage (SunLive)
• Rena - shipwreck that shook the nation (NZ Herald)
• New Zealand Herald's Rena oil spill interactive
• Rena Twitter feed