At that time a draft decision will be released on whether the reef should be added to the UN World Heritage in danger list due to the lingering threats of poor water quality, industrial development and climate change.

While the ultimate decision will be made at a meeting starting next month by 21 countries sitting on the UN's World Hertiage Committee, the draft – prepared by the International Union for Conservation of Nature and the World Heritage Centre – is hugely influential.

A potential "in danger" listing for the reef has caused agony for the Abbott government, which has put much diplomatic sweat into stopping it.

So any word on what the decision might be?

Nobody knows for sure. But the informed view is that an "in danger" listing will not be recommended. Environment Minister Greg Hunt told Fairfax Media he was "increasingly confident" of this.

Instead Mr Hunt said he proposed to the head of UNESCO, Irina Bokova, at an April meeting that Australia would instead report back on its progress in reef protection by 2020. A two-year review is also on the table.

What does it matter if it is on some list?

Federal cabinet agreed to launch the diplomatic push to avoid the danger designation because of the reputational damage it would cause and the brand damage it could do to the reef tourism industry.

But more significantly, it is understood the government also feared a listing would give environment groups extra momentum in their campaign to stop the massive expansion of coal projects alongside the reef and prevent international banks from financing them. The government wants major infrastructure projects, including development of the Galilee Basin, to go ahead.

Why is there so much concern for the reef's health?

The UN first became alarmed in 2011 when a huge number of proposed coal and gas port projects emerged along the reef's coast. Proposed dumping of dredge sludge from the Abbot Point coal port expansion in the reef's water became a focus.

That came on top of ongoing water quality problems, invasive pests and the threat of climate change. The reef has been in a bad way. And in 2012 it was estimated 50 per cent of its coral cover was lost over the previous 27 years.

So if there is no listing, what has turned it around?

Mr Hunt points to two recent commitments that have significantly helped Australia's cause – a $200 million boost to improving water quality by stopping runoff, and a ban of spoil dumping in the Great Barrier Reef Marine Park. The new Queensland Labor government has also made a number of commitments, including ensuring the disposal of dredge spoil only occurs on land.

But it might also be due to the enormous diplomatic push behind the scenes.

Last year the Abbott government set up a taskforce, led by ministers Mr Hunt, Julie Bishop and Andrew Robb, to lobby the heritage committee member countries.

Ministers have written or spoken to their counterparts in the 21 member countries. Mr Hunt said he had visited 15 countries personally. And Australia's environment ambassador, Peter Woolcott, and the environment department deputy secretary Kimberley Dripps have also been deployed.

A Senate estimates hearing this month heard $100,000 had been spent flying bureaucrats to lobby UNESCO representatives. The government has also brought international visitors, officials, foreign ministers and journalists to the reef for tours.

So is the reef in the clear?

Not so fast. WWF campaigner Richard Leck says having plans to better protect the reef are one thing, but implementing them would be the hard part and governments must be held to their word. He also says, by the group's calculations, commitments to reverse the reef's decline are still $500 million short over five years.

And while governments might make headway on water quality and curb development impacts, climate change still looms.

A major government assessment of the reef last year declared climate change its most serious threat. How bad it will be depends on how well the world, including Australia, curbs greenhouse gas emissions.