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Water quality

Key Messages

  • We need clean water to protect our freshwater, estuarine and marine plants and animals. Poor water quality has been attributed to algal blooms, declines in seagrass and coral loss. It can also affect our drinking water supplies. Poor water quality can be caused by run-off from different land uses (e.g. cane growing, grazing, horticulture and urban land use) as well as discharges from point sources (e.g. pipes). The major source of poor water quality is from diffuse sources (agriculture and urban run-off such as stormwater).

    Many marine systems, such as the Great Barrier Reef, are likely to face a number of pressures from climate change into the future. Improving water quality and reducing some of the local stressors will help improve resilience against the likely impacts from climate change.

  • Water quality is highly variable year to year in many regions depending on rainfall. As a result, a combination of monitoring and modelling is often used to better understand long-term improvements in water quality.  Depending on location and community interest, water quality report cards report on condition of habitat, water quality and other ecosystem features.

    Regional waterway health report cards provide finer scale information on water quality in local streams, rivers and bays. These show that many waterways are in poor condition, and that the condition is heavily dependent on rainfall during the relevant period.

  • Nitrogen and phosphorus are significant contaminants resulting from both diffuse sources (e.g. farmlands) and point sources (e.g. sewage treatment plants): they cause ecological imbalance through growth of algae and other species. Upgrades of sewage treatment plants help reduce these contaminants release. Continuous monitoring is needed to determine when upgrade or expansion of plants has become necessary due to population growth. Current levels of contaminants from sewage treatment plants are relatively stable.


Water quality report card coverage

Water quality report cards have been prepared for many of Queensland’s coastal catchments and for parts of the Murray–Darling Basin. Depending on location, these report cards include condition of habitat, water quality and other ecosystem features at different spatial and time scales. In other areas, where report cards have not been prepared, there are varying scales of monitoring within the catchments.

Condition of aquatic ecosystem health

Queensland’s aquatic ecosystems vary significantly in condition. Some are in pristine condition while others do not meet standards for water quality.


Pressures affecting Queensland’s aquatic ecosystems

The pressures affecting Queensland's aquatic ecosystems vary depending on local conditions and land management use and practices. Broadly, sediments, nutrients and pesticides are the main catchment pressures on our aquatic ecosystems. Climate change is also a pressure on aquatic ecosystems, particularly the Great Barrier Reef.

Volume and load of sewage treatment plants

The annual volume and load of nutrients released from coastal sewage treatment plants into waterways in Queensland has been collected since 2010. In general, we have observed that the loads of nutrients, particularly nitrogen, are correlated with the annual volume. However, loads of nutrients in some locations have reduced in recent years despite high annual volumes and were attributed to improved treatment in these locations.


Healthy Land and Water South East Queensland report card

The Healthy Land and Water South East Queensland Report Card covers 18 major river catchments from the Noosa River Catchment to the New South Wales Border, as well as the marine areas of Pumicestone Passage, Moreton Bay and the Broadwater. The report card is an annual commentary of the state of estuarine, marine and freshwater health with waterway monitoring from about 400 sites across the region.

An environmental condition grade is calculated based on 25 indicators for each of the catchments to assess key freshwater and estuarine aspects of the waterways. Indicators are assessed against established guidelines and benchmarks, resulting in the single grade for each catchment.

Reef Water Quality Report Card and Paddock to Reef Integrated Monitoring, Modelling and Reporting Program (Paddock to Reef Program)

The Reef 2050 Water Quality Improvement Plan 2017–2022 seeks to improve the quality of water flowing from the catchments adjacent to the Great Barrier Reef. The plan builds on previous water quality plans by setting separate targets for reducing water pollution from each catchment to enable better prioritisation of actions.

The Reef Water Quality Report Card 2017 and 2018 assess the results of Reef 2050 Water Quality Improvement Plan’s actions reported up to June 2018. For the first time, the results in the Report Card are reported at a finer catchment and sub-catchment scale.

The Paddock to Reef Program provides the framework for evaluating and reporting progress towards the Reef 2050 Water Quality Improvement Plan targets and objectives through the report card. Monitoring and modelling of water quality occurs across a range of attributes, from paddock scale through to sub-catchment, catchment, regional and Great Barrier Reef-wide. The Paddock to Reef program evaluates management practice adoption and effectiveness, catchment condition, pollutant run-off and inshore marine condition.

Fitzroy Basin Report Card

The Fitzroy Basin Report Card reports on aquatic ecosystem health of freshwater and estuarine condition for the Fitzroy Basin, as well as drinking water results for Rockhampton and Central Highlands. The report card helps inform consideration of whether current management strategies are proving successful in maintaining the health of aquatic ecosystems and helps guide and improve planning and investments towards improved aquatic ecosystem health by governments and all partner organisations.

Gladstone Harbour Report Card

The Gladstone Harbour Report card reports on estuarine and marine condition in the harbour based on monitoring of ecological and biological indicators, and also reports on social, economic and cultural indicators. The report card helps enable stakeholders to have confidence in the efforts to maintain and improve the health of the harbour.

Mackay–Whitsunday–Isaac  Report Card

The Mackay–Whitsunday–Isaac Report Card, reports on the health of the region’s waterways, including the catchments of the Don, Proserpine, Pioneer, O’Connell and Plane basins, 8 estuaries, and the inshore and offshore marine areas to the eastern boundary of the Great Barrier Reef. The report card helps community, industry, science, tourism and government to work together to determine what more can be done to look after our waterways.

Wet Tropics Report Card

The Wet Tropics Report Card assesses the health of the major rivers, estuaries, inshore and offshore reefs in the Wet Tropics region. The Daintree, Mossman, Barron, Mulgrave, Russell Johnstone, Tully, Murray and Herbert freshwater basins are assessed for water quality, habitat and hydrology, and fish. The report card communicates information on waterway health, enables long term trends to be identified and supports action to improve the health of Wet Tropics waterways.

Townsville Dry Tropics Report Card

Released in 2019, the pilot report card provides information on the ecological condition of waterways, and the community and economic benefits provided by waterways. The results on the condition of freshwater basins, estuarine/coastal, inshore marine and offshore marine environments within the Townsville Dry Tropics region are detailed. The results provide scores and grades for indicators, indicator categories, indices, and overall scores for the categories of Water, Biodiversity, Community and Economy within 7 zones. The report card additionally includes a qualitative confidence measure for each score for the indicator categories within Water and Biodiversity. The confidence is based on the accuracy of the data used in the analysis.

QCatchments program

The QCatchments program can be scaled up or down from province to catchment level depending on information needs. The program moves across the state depending on priorities, with assessments generally undertaken to support water planning assessments. The QCatchments program identifies priority threats to aquatic ecosystems, reports on the condition of the ecosystem, improves understanding of ecosystem processes and the influence of threats, and guides natural resource decision-making processes.

Surface Water Quantity and Quality Networks and Groundwater Level and Quality Networks

The networks assess the state's water resource availability by providing data for hydrologic analysis, operation and management activities to ensure the productive and responsible use of natural resources.

Water Tracking and Electronic Reporting System (WaTERS)

The Water Tracking and Electronic Reporting System (WaTERS) currently receives water quality monitoring data from more than 200 facilities across Queensland that are approved to release water to the environment. About half of these facilities are sewage treatment plants. Other facilities include large coal mines, coal seam gas activities and industries in Gladstone and South East Queensland.