NZ's worst marine oil spills

The grounded log carrier Jody F Millennium in Gisborne with oil being pumped into a specialised inflatable barge alongside. File photo / Richard Robinson

The Rena oil spill crisis is fast becoming one of New Zealand's worst marine oil spills in its history.

The cargo vessel has leaked between 130 and 350 tonnes of oil since grounding on the Astrolabe Reef off the Tauranga coast last Wednesday.

Environmental groups and Bay of Plenty residents are bracing themselves for an ecological catastrophe as oil continues to wash up the region's beaches.

With 1,700 tonnes of oil on board, and fuel continuing to leak from the vessel, authorities say the crisis will take weeks or months to tackle, rather than days.

Maritime New Zealand's website lists five incidents it calls "the more significant marine oil spills" in New Zealand waters since 1990.

Don Wong 1998

In 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

In 1999, the container ship MV Rotoma discharged around 7 tonnes of oily water off the Tutukaka coast, creating an oil slick 6 km long.

The ship's owner, Australia New Zealand Direct Line, and agent, Anglo Eastern Ship Management, 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 a fire on board rendered it immobile.

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 log ship Jody F Millennium to break free from her moorings in Gisborne Harbour. After efforts to secure her to the wharf failed, the vessel was towed out to sea. However as she was being towed out another huge swell knocked the vessel and she ran aground on a beach, where she remained stranded for 18 days.

The vessel leaked 25 tonnes of heavy fuel oil into Poverty Bay affected an area of about 8km of coastline from Tuahine Point to 300 metres along the coast, about opposite Gisborne Airport.

Tai Ping 2002

The fifth incident on the list did not actually involve any spilling of fuel.

In 2002, the Hong Kong-flagged bulk carrier Tai Ping ran aground off at Tiwai Point near the entrance to Bluff Harbour. Authorities planned for a significant oil spill, however after being grounded for nine years, the vessel was refloated with no fuel spilt.