Great Barrier Reef's World Heritage status

TIMELINE OF THE GREAT BARRIER REEF'S WORLD HERITAGE STATUS

* 1981: Inscribed as a World Heritage site

* 2011: UNESCO's World Heritage Committee expresses "extreme concern" over multi-billion-dollar LNG processing facilities at Curtis Island. Calls for an assessment of the reef, including a long-term plan for sustainable development, and requests an international monitoring mission be allowed to visit the reef

* 2012: Committee warns the reef could be listed as a site "in danger" unless Australia makes substantial changes, raising concerns about coastal developments and the lack of an overall plan. Sets out a list of recommendations

* May 2013: A study by UNESCO and the International Union for Conservation of Nature says decisive action is needed to avoid an "in-danger" listing at the next committee meeting. It claimed the federal and Queensland governments failed to improve water quality or halt coastal developments that could affect the reef

* June 2013: Committee delays decision over whether to put the reef on the "in-danger" list, again putting Australia on notice

* June 2014: Committee again delays decision and raises concerns about the decision to dump dredge spoil in the marine park as a part of the Abbot Point coal expansion. Australia commended for progress in improving water quality and intention to restrict port developments

* Feb 2015: Australia reported to the committee on its progress

* May 29, 2015: Committee to release its draft decision on whether to list the reef as "in danger"

* June 2015: Final decision due