Water quality and the reef

Improving water quality is the best way we can support the health of the Great Barrier Reef locally.

While climate change remains the biggest threat, improving the quality of water flowing from the land is critical to reducing pressure to support the Reef’s resilience and recovery.

Freshwater flowing from the land and into rivers floats on the sea water and is pushed back against the coast and driven northwards by the prevailing south-east winds. This freshwater is largely trapped in the Great Barrier Reef lagoon and impacts the inshore area.

Coral reefs make up approximately 7% of the total of the Great Barrier Reef Marine Park with 3.6% found within the inner shelf area closer to the coast. Other important inshore ecosystem habitats include coastal wetlands, estuaries, mangroves and seagrass meadows.

One of the most manageable impacts on these important inshore habitats is human-induced run-off of pollutants. For this reason, the Australian and Queensland governments are investing significant funds to reduce the run-off of sediment, nutrients and pesticides from catchments.

The health of the Reef and many of its species, particularly fish, seabirds and marine reptiles, also rely on maintaining connectivity between the different habitats.

In response to mass coral bleaching events and the deteriorating outlook for the Reef, the governments recognised the need to accelerate priority actions to improve Reef health. The Reef 2050 Long-Term Sustainability Plan (Reef 2050 Plan) and Reef 2050 Water Quality Improvement Plan (Reef 2050 WQIP) aim to protect the Reef’s values.

While the main source of water pollution is agriculture, the Reef 2050 WQIP includes a diverse set of actions and recognises urban and industrial areas can create concentrated pollution that has important local impacts. It includes targets for improving water quality leaving the catchments to help prioritise actions.