Catchment water quality targets

Water quality targets have been set for the 35 river catchments flowing to the Great Barrier Reef. These targets define how much land-based pollution needs to be reduced to meet the ecological thresholds that protect the Reef’s ecosystem, and supports their recovery. The targets are grounded in scientific understanding of the conditions that coral and seagrass need to survive and form an integral part of the Reef 2050 Catchment Water Quality Strategy.

To learn more about the science behind the targets read the 2026 Scientific Report on the Great Barrier Reef Water Quality Targets (PDF, 18.1MB) and Supplementary Information (PDF, 21.3MB) , or the Summary (PDF, 4.0MB) .

Focusing efforts to protect the Reef

The catchment water quality targets along with prioritisation and decision support tools and frameworks, like the Spatial Management Prioritisation Framework and catchment profiles, help to identify the highest priority areas for improving water quality.

This information helps guide local actions to improve water quality and support the health and resilience of the Reef.

Catchment water quality targets

The table below shows the end-of-catchment load reduction targets for the 35 catchments. These targets focus on reducing:

• dissolved inorganic nitrogen (DIN)
• fine sediment
• particulate nitrogen (PN)
• particulate phosphorus (PP).

In some catchments, current pollutant loads are low enough to meet ecological thresholds. For these areas, a Prevent Load Increase (PLI) approach is applied. This means:

• No immediate reductions in pollution are required.
• Proactive management is recommended to ensure pollution levels don’t increase over time.

Actions include maintaining good land management practices and preventing new development or land.