Five months to the day of the 236m container ship Rena grounding on the Astrolabe Reef, salvage teams have processed nearly half of the 1368 containers onboard it on October 5.

Svitzer salvors have discharged 571 containers from the wreck and Braemar Howells has recovered 72 from the water and beaches in the Bay of Plenty.

A barge carries two broken containers from the Rena wreck to shore. Photo: LOC.

Combined, this is 643 containers, just 41 containers short of the halfway mark of 684.

When the ship ran aground there were 547 containers stored above deck and 821 containers stored in the vessel's hull.

There were 121 containers carrying perishable foodstuffs and 32 with goods classified on the ship's manifest as ‘dangerous'.

Maritime New Zealand estimates there are about 250 containers still in the bow section of the ship that is above water on the reef.

The salvors have been unable to ascertain how many containers are still inside the sunken stern section of the wreck.

If there are 250 containers in the bow section of the ship then there are 375 containers unaccounted for.

A good proportion of these are expected to be in the stern section of the wreck, it just cannot be confirmed.

Others are likely lost at sea, most likely sunken near the reef.

Bad weather at the weekend saw no container removal operations undertaken at the Astrolabe Reef.

The Smit Borneo crane barge came into port last week and is due to return to the wreck site early this week.

When it arrives, Svitzer salvors, who are housed on the barge, intend to install new mooring chains on the wreck.

Today, Svitzer is sending a small salvage team to the wreck by boat and is flying a helicopter out to remove the last refrigerated container located on the deck of the bow section.

Aerial surveillance of the wreck indicates no further damage was sustained owing to the storm at the weekend, but it did prevent any on-water clean-up work from going ahead.

Instead, Maritime New Zealand clean-up operations were carried out by means of beach surveys between Waihi Beach and Bowentown, down the coast to the Kaituna Cut area.

A barge and fast response vessel are at White Island and Whale Island today to pick-up debris.

Clean-up operations continue at Matakana Island today with helicopter lifting of timber to a waiting barge – other debris will also be moved off the island.

Timber that has been wood-chipped will be used to surface roads on the island and work will be underway on that project today.