Watching the rear of the Rena slip beneath the sea yesterday, the country could count itself wiser in the ways of a modern shipwreck. Perhaps the most obvious lesson to the layman is how well constructed these container ships must be. The Rena foundered more than three months ago. It has survived that long despite frequent storms, giving salvors time to remove most of its fuel oil and many of the containers on its deck.
Dangers remain, of course, from the 830 containers still on board when the vessel finally broke apart on Saturday and from an unknown quantity of oil that may leak from the hull. But it has not been the environmental disaster we were warned to expect in the days following the grounding.
It was dismaying to hear those warnings from the ministers whose job it was to ensure that everything was done to prevent such a catastrophe. The nation appeared bereft of equipment and expertise to deal with the kind of maritime disaster that must alway be a risk considering New Zealand's location and weather.
We had to await the arrival of salvors from Holland and a sea crane from Singapore while Maritime New Zealand carried out a disaster management plan that involved little more than cleaning up the coast as best it could if an oil slick came ashore.
That plan, as far as it goes, was strikingly successful this time. Though countless seabirds perished from the slick, the beaches were cleaned so quickly and efficiently that they were safe for swimming, fishing and other activities before Christmas.
We may have been lucky. A Waikato University oceanographer, Dr Willem de Lange, reckoned the Bay of Plenty "dodged a bullet" when wind and currents took 350 tonnes of leaked oil on to beaches and rocky shores rather than into estuaries, which are almost impossible to clean. But credit must be given to the organisers of the clean-up, and the hundreds of military personnel and volunteers who removed nearly 1000 tonnes of sludge, tar balls and fouled sand.
Credit must also be given to the professional salvors who work on heaving, dangerous wrecks amid towers of containers that appear to be on the point of toppling.
The Rena's fuel lines had been damaged when it struck Astrolabe Reef and the salvors had to rig up new lines for the heavy oil to be removed. To reach the last tank, which was submerged, they had to swim in corridors of oily murk.
Their priority was properly the removal of oil, but by December they were able to turn their attention to the 1114 containers still on board. The arrival of a larger crane barge from Singapore enabled most of the deck cargo to be cleared in the past month, despite weather interruptions. The operation has been impressive.
Many questions will remain, though, for an inquiry into the handling of the disaster. Did the Government respond quickly enough in the days after the grounding? Did it put sufficient pressure on ship-owners to call in salvors quickly? Did liability considerations cause the Government to hold back?
But, more important, should New Zealand maintain a marine disaster corps of its own? Or do accidents on our coasts occur too rarely to warrant buying and maintaining the equipment and expertise that would be required?
More practically, there must be some means by which oil slicks can be contained and chemically dispersed, and how hard would it be these days to put a global positioning device in every container?
But quibbles after the fact do not alter the impression that after a slow start, the response has been effective. If the Rena has been our worst maritime environmental disaster, it could have been much worse.