Four-and-a-half years after the cargo ship Rena grounded on the Astrolabe reef, the clean-up has officially been completed and the reef can now be fished and the wreck dived.
Today Maritime New Zealand removed two hazard notices on the wreckage and the Bay of Plenty harbourmaster says small vessels will be allowed back in the area from tomorrow morning.
The 37,000-tonne Rena ran aground 12 nautical miles from the entrance to Tauranga Harbour in October 2011. It spilled oil, shipping containers and debris into the ocean in what became New Zealand's worst maritime environmental disaster.
More than 22,000 tonnes of debris has been removed from the seabed since, says Maritime NZ director Keith Manch.
"All reasonable efforts have been made to remove entanglement hazards and wreckage, where possible," he said.
"I have concluded that the wreck and remaining debris on the sea floor no longer constitute a hazard to navigation."
Most of the ship's oil and harmful substances had been removed or discharged into the sea, but it would continued to be monitored.
The Bay of Plenty Regional Council says the Rena wreckage, which has been salvaged to below the waterline, occupies less than 2 percent of the 49ha of the Astrolabe reef.
Harbourmaster James Buell is removing the previous 2 nautical mile restrictions on vessels under 500 tonnes from tomorrow 8am.
The Rena's Greek owners, Daina Shipping, say they and their insurers have spent more than $500 million on the clean up.
Daina director Konstantinos Zacharatos in a statement acknowledge everyone who helped in the response.
The volunteer Maketu Coastguard would be funded to be an onsite reef advisor and buoys would mark the recommended stern and bow dive sites.
However, they warned the deeper stern section should only be attempted by qualified PADI technical divers.
An investigation blamed crew error in the Liberian-flagged ship sailing too close to the reef. The captain and first mate were jailed for seven months and the government reached a $38 million compensation deal with the ship's Greek owners.
Earlier this year, permission was granted for the remains of the wreck to stay on the reef.