How EPA protects freshwater environments

EPA’s programs to monitor the state’s freshwater environments include:

More useful, non-EPA information about biodiversity management issues in rivers and streams is available in monitoring Victoria’s waters.

Biological monitoring and assessment

Traditional water quality monitoring involves measuring physical and chemical aspects of water, including  pH, salinity, turbidity (‘murkiness’), nutrient levels and the amount of dissolved oxygen. They provide a snapshot of environmental conditions at the moment the samples were taken.

EPA uses a more holistic approach to environmental assessment in rivers and streams, incorporating biological indicators of ecosystem health. Plants and animals respond to disturbances and toxicants, and this can be assessed from occasional sampling of the community (commonly, once or twice a year). We can assess the net effect of all environmental factors, including cumulative impacts over periods of weeks, months or years.

EPA does most of the invertebrate monitoring carried out across the state. Our statewide biological monitoring program has been in place since 1990.

Aquatic invertebrates are small animals, generally less than 1 cm long, including insects, snails, worms and shrimps. They are critical to a healthy stream ecosystem, both by processing energy and being a food supply to yabbies, fish, platypus and birds.

The presence or absence of specific types of invertebrates is one way we can get information about environmental quality. Other information can be obtained from the number of animals found in a stream (abundance), number of different types of animals found in a stream (biological diversity) and the relationship between all animals present (community structure).

River health and environmental condition reports

Monitoring and assessing environmental conditions gives us essential feedback on the state of our river systems. This allows water resource managers to develop and refine programs so they can direct resources and activities where they are needed most.

The statewide biological monitoring program assesses invertebrate communities using a rapid bioassessment method, described in Risk-based assessment of ecosystem protection in ambient waters (publication 961, November 2004).

Information from the biological monitoring program is used to provide assessments of the environmental condition of rivers and streams across Victoria:

Environmental quality objectives

Surface waters and their aquatic ecosystems should be free of any substance that will pose a risk to beneficial uses - the different uses and values of water, including drinking, industrial use and aquatic ecosystems, that a waterway or waterbody can support. The same must be true of any human impacts on these systems.

These impacts appear, for example, as ill effects on human health, increased fish kills and algal blooms, excessive growth of aquatic plants, sedimentation, loss of biodiversity and environmental flows, and litter and other harmful substances in water environments.

Victoria has environmental quality objectives for protecting rivers and streams in the State Environment Protection Policy (Waters of Victoria). The objectives acknowledge the wide variety of aquatic ecosystem types, which all function quite differently and are affected or threatened by different issues. They describe the level of environmental quality needed, in most surface waters, to avoid risks to beneficial uses and to protect them.

Failure to attain an objective triggers further investigation of the risks to beneficial uses. Actions are then implemented or regionally appropriate objectives developed. For more information, background papers on the objectives can be accessed from EPA's publications catalogue:

Lakes program

Victoria has a wide variety of inland lakes, including billabongs, volcanic lakes, sand-dune lakes and reservoirs. Some have naturally high salinities and animal and plant communities that make them very different from lakes elsewhere in the world. Historically we have not had a good understanding of the ecology of our unique lake systems.

EPA's investigations into the condition of Victoria's lakes have developed a better understanding of how our lakes work and produced guidelines to help protect them.. The guidelines, Environmental quality guidelines for Victorian lakes (publication 1302), were released in 2010.


Page last updated on 30 Oct 2018