Water quality is fundamental to biodiversity, and to the health of people, animals and the environment. Victorian water quality is negatively affected mostly by salinity, turbidity, nitrogen and phosphorus. However, pH levels, pesticides, heavy metals and temperatures are of increasing concern in some regions.

The science evidence that informed this assessment is available in this Water Quality chapter PDF icon SoE2018ScientificAssessment_WQ.pdf 

What the indicators tell us

No clear statewide picture emerges from the indicators. Water quality varies between different parts of the state, and the indicators are spread fairly evenly between good, fair and poor. However, no indicators are showing an upward trend, suggesting that water quality is not improving.

The Water Quality Indicator Report Card provides an assessment summary of all indicators in this chapter PDF icon SoE2018IndicatorReportCard_WQ.pdf 

Themes and indicators: How does Victoria measure up?

Algal blooms

Acquatic ecosystem health

Healthy aquatic ecosystems depend on the quality of water for critical processes such as nutrient cycling, primary production and the creation of suitable habitats to support diverse communities of aquatic animals and plants.

Water quality is influenced by a range of factors, including:

  • climate (patterns of rainfall and drought)

  • land use (adjacent to waterways, but also in the catchment)

  • water-resource use (extraction of water for drinking and agriculture, and discharge of stormwater and wastewater)

  • ecosystem processes (such as water-sediment interactions and nutrient cycling)

  • extreme events such as bushfires.

There are many aspects to water quality, including physical properties such as temperature and water clarity, concentrations of chemical components, such as salinity and dissolved oxygen, and biological processes such as algal growth.

The assessment of water quality in this report focuses on five water-quality indicators: dissolved oxygen, salinity (electrical conductivity), nutrients (total nitrogen and total phosphorus), water clarity (turbidity) and alkalinity (pH).

No statewide data was available for suspended solid concentrations in rivers, or for water temperature and chlorophyll-a concentrations in rivers. These indicators are generally less relevant for Victoria’s water quality, although they can inform specific water-quality issues on localised scales. For example, suspended solids can indicate impacts, such as erosion, from localised to catchment scale. Chlorophyll-a can indicate the potential for algal blooms and fish kills.


Pollution incidents

More detail


Water quality is fundamental to the ecosystem services that inland waters provide, such as drinking water, cycling of nutrients, maintenance of biodiversity, and recreational and cultural opportunities. Poor water quality has serious implications for the ecological health of inland waters, biodiversity, and human and livestock health.

Water-quality pollution generally arises from point-source discharges (directly from industry and treatment plants) or diffuse sources (runoff from catchments). Regulatory improvements have reduced point-source water pollution. Diffuse sources, such as urban stormwater, are now the most significant contributor to pollution of Melbourne’s rivers, creeks and wetlands. The projected increase in extreme rainfall events in Victoria is highly likely to amplify the effects of urban stormwater pollution unless practical solutions are implemented.

The main water-quality issues for Victoria have traditionally been salinity, turbidity, nitrogen and phosphorus. At a state and national level, these variables are considered the most significant river contaminants. However, there are numerous other variables that contribute to water quality, such as pH, pesticides, heavy metals and temperature, which may have local or regional significance. Water quality is also affected by interactions between these components. For example, salinity and temperature both affect the saturation concentration of dissolved oxygen.

When SoE 2013 was issued, the Department of Environment, Land, Water and Planning (DELWP) had not analysed the raw monitoring data that had been collected, and was unable to provide a statewide assessment of water quality. Consequently, SoE 2013 contained only a limited update of water quality from SoE 2008. The 2008 assessment showed that water quality was generally poor in much of Victoria, particularly in Victoria’s lowlands and in the west of the state.

There has been an increased focus on the water quality sector since 2013. DELWP conducted an internal audit of its water-quality monitoring programs in January 2015, prior to a Victorian Auditor-General’s Office (VAGO) audit into Victorian water-resource monitoring, completed in May 2016.

The VAGO audit made three recommendations in response to a central finding that, although some individual programs are coordinated and governed well, oversight of the individual long-term water-quality monitoring programs in the Port Phillip Bay and Western Port region is deficient. The deficiency was due to inadequate coordination across all programs among the three relevant agencies: DELWP, Melbourne Water and Environment Protection Authority Victoria (EPA Victoria). The issue is less prevalent in the nine other catchments where DELWP has the clear coordination role. Specific findings from the VAGO audit included agencies not having a formal cooperative approach to monitoring, reporting and evaluating the individual monitoring programs in the region, and agencies not sharing and using data efficiently to meet reporting needs. The DELWP and VAGO audits informed the Victorian Government’s water plan, Water for Victoria, released in October 2016.

Other organisations that help to manage water quality are Catchment Management Authorities (CMAs), which develop and implement waterway management strategies, and EPA Victoria, which implements the State Environment Protection Policy (Waters) (SEPP (Waters)) and regulates water quality.

Victoria also contributed to the development of the Basin Salinity Management 2030 strategy, which is responding to the environmental, social and economic risks posed by salinity in the Murray–Darling Basin.

Water-quality monitoring has been a greater focus of state and departmental strategies since SoE 2013. Consequently, SoE 2018 is a significant update to water-quality information, due to the trend data that has been supplied by DELWP on a range of quality indicators measured at approximately 80 sites.

A warmer climate will lead to higher water temperatures, affecting the distribution of many aquatic species. Increased temperatures also have water-quality implications, including reduced concentrations of dissolved oxygen and therefore a potential increase in algal blooms. Increased bushfires will also impact on water quality and riparian vegetation.

Critical challenges facing Victoria’s management of water-quality impacts now and in the future include:

  • balancing the needs of catchment and waterway health with human and agricultural water consumption needs

  • managing urban growth and its impact on urban waterway health

  • ensuring that long-term water-quality monitoring is coordinated and shared among the lead agencies (a key recommendation of the 2016 VAGO audit)

  • maintaining long-term water-quality monitoring data so that it is easily accessible and suitable for informing policy and strategy development

  • ensuring a coordinated approach to ‘citizen science’ (which incorporates public participation in research) in the water-quality sector. Citizen science programs are more prevalent in water-quality than in other sectors. Ensuring that lead agencies design and target programs with a similar level of rigour will help to maximise the value of community participation

  • identifying strategies to tackle the likely increase in stormwater pollution incidents associated with more frequent and intense rainfall events.

Other challenges are mitigating against:

  • increasing stormwater and wastewater discharges from urban areas

  • altered water regimes, salinity and algal blooms

  • an increase in catchment inflows from diffuse sources

  • localised events, in which individual water-quality stressors, including nutrients, sediments, toxicants and pathogens, exceed objectives.

Note that this section refers to surface water only: groundwater quality is covered in the Water Resources section.

Current Victorian Government Settings

In October 2016, the Victorian Government released Water for Victoria, a plan for the management

of Victoria’s water resources, now and in the future.

The plan includes commitments to improve Victoria’s existing waterway monitoring programs, invest in community partnerships and citizen-science initiatives, strengthen integrated catchment management, and deliver a new SEPP to protect water quality.

The plan invests $222 million for catchment and waterway health, to better balance the needs of the environment with water consumption needs. This investment includes water for the environment, riparian restoration and other programs.

The government has also established a series of Integrated Water Management Forums across the state. In these forums, the water sector and the community work together to plan, manage and deliver water in towns and cities.

To help manage urban growth and its impact on urban waterway health, the government has developed a range of water policies, including Water for Victoria, the Yarra River Action Plan, the Plan Melbourne Implementation Plan and the Port Phillip Bay Environmental Management Plan.

Melbourne Water’s responsibility is to create long-term plans that ensure the region’s waterways are healthy, liveable and accessible. Melbourne Water’s Healthy Waterways Strategy 2018 is intended to address future urban waterway management needs. As part of the Melbourne Urban Stormwater Institutional Arrangements Review, DELWP is reviewing the arrangements between Melbourne Water and local government authorities to clarify responsibilities for urban stormwater risk management, related assets and services in the Melbourne metropolitan area. A recommendations paper is scheduled for completion in late 2018. The government has also established the Improving Stormwater Management Advisory Committee to provide independent advice on planning and development controls for improving stormwater management and strengthening the links between water management and urban planning.

The 2003 SEPP (WoV) was the government’s primary water-quality policy. However, it did not provide clarity on the roles and responsibilities of the lead agencies involved in long-term water-quality monitoring. The government committed to ensuring that the water-quality standards and objectives that are the basis of policies reflect best-available science, and provide clear and relevant standards and obligations to protect and improve the health of Victoria’s water environments. To do this, the government has updated and merged the Waters of Victoria SEPP and the Groundwaters of Victoria SEPP, to create the new SEPP (Waters).

Future Focus

Improvements in statewide water quality data availability have translated into a much more robust assessment of water quality indicators presented in this SoE report compared to the SoE 2013 report. This demonstrates that steps were undertaken since the last SoE report to increase data availability, in line with the SoE 2013 recommendations and subsequent VAGO and DELWP audits that identified a deficiency in data usage and sharing. There are still considerable improvements to be achieved by coordinating monitoring programs and data between government agencies, industry and community. Advances in monitoring will also need to be complemented by improvements to data and trend analysis and modelling.

An Agile Water Quality Monitoring Framework

Future water quality monitoring needs to include a network of long-term sites complemented by targeted monitoring of water pollution hotspots. Where and how this monitoring is completed, and who does it, needs to be determined in a transparent process, guided by evidence and ultimately recommending clearly defined roles and responsibilities. The water quality monitoring framework would be developed by DELWP with support from other agencies and community. The framework would be a risk-based approach that uses threats and pressures on water quality to guide where and how monitoring is undertaken.

These reforms will support Victoria’s progress to a modern regulatory environment for water quality protection and align with recommendations 6.3 and 7.2 of the 2016 Ministerial Advisory Committee (MAC) Inquiry into EPA Victoria to ‘assess the adequacy of its air and water monitoring networks, particularly in relation to air quality and consider options to improve data sharing and accessibility, and community communication’ (recommendation 6.3); and implement, through DELWP, statewide environmental monitoring, a spatial data system and reporting on outcomes (recommendation 7.2). The reforms will be essential for monitoring delivery of the State Environment Protection Policy (Waters) and the Environment Protection Amendment Act 2018.

Combining targeted monitoring of pollution hotspots with monitoring at priority long-term sites will help inform pollution prevention interventions in hotspots and enable quantitative evaluations of those actions. Enhancements to EPA’s pollution reporting database would assist the determination of potential hot-spot areas for monitoring.

Recommendation: That DELWP, working with its portfolio agencies, implements an agile water quality monitoring framework which (i) clarifies the roles and responsibilities of all agencies and the community, (ii) improves monitoring of pollution hotspots and (iii) builds on EPA Victoria’s implementation of EPA Inquiry recommendations 6.3 and 7.2.  PDF icon SoE2018Recommendations_WQ.pdf

UN Environmental Economic Accounts

Under the System of Environmental-Economic Accounting (SEEA), there are water-quality accounts and water-emissions accounts, along with water-resources accounts (discussed in the Water Resources chapter).

Water-quality accounts are linked to water-resources accounts and describe the stocks of water at the beginning and end of an accounting period, according to their quality. Water quality is a key determinant of what water can be used for, and consequently is a key factor in determining the benefit of water resources to the economy.

In environmental-economic accounting, water pollution is categorised as a residual flow from the economy to the environment. A water-emissions account records this connection, recording both pollutants that enter the environment directly (either point-source emissions or non-point-source emissions such as urban and agricultural runoff) or through a treatment plant. Water-emissions accounts present information on the sectors (such as industry, government and households) responsible for emissions, the type and amounts of pollutants, and the destination of the emissions (for example, water resources or the sea). Water-emissions accounts should report emissions in line with industry classifications used by the Australian Bureau of Statistics.

Tracking water-pollution emissions over time, along with economic activity, can help highlight trends in the relative contributions of different sectors, including future levels expected with growth in economic activity. This type of account can also be used to assess efforts by government, industry and households to reduce water-pollution emissions.

Emissions to water resources can constitute a major environmental problem and cause the quality of water resources to deteriorate. Some substances are highly toxic (such as heavy metals); others, such as nitrogen and phosphorus, can lead to eutrophication. Organic substances can have effects on the oxygen balance, impacting the ecological status of a resource.

The impact of residual flows of water pollution on people and the environment already appears to some extent in Victoria’s traditional economic accounts (the System of National Accounts). For example, these impacts would be included as expenditure in the health system from doctor visits and hospital admissions, or reductions in property values due to decreased amenity near water bodies. However, the amounts attributable to water pollution are not identified in the traditional accounts. Expenditure to prevent and manage the impacts of water pollution currently count towards Victoria’s gross state product, rather than being recorded as a cost to the Victorian community.

Water-pollution emissions can affect the condition of assets, including water resources and freshwater and marine ecosystems. Emissions can impact on ecosystem functioning and the capacity of assets to support ecosystem services. Examples include provisioning services such as water supply; regulating services such as dilution/filtration of pollutants and water-cycle regulation; and cultural services such as recreation and tourism, and ecosystem capital for future generations.

The SEEA framework also recognises the benefit to the ecosystem of water purification by natural assets. An ecosystem account would record this connection by showing the quantity of water-pollutant emissions absorbed or diluted by natural assets, the impact of this on water quality and the corresponding benefit to the Victorian community in terms of avoided impacts.

Case studies

Community water monitoring for Waterhole Creek, Morwell

Citizen scientists, the EPA and the West Gippsland Catchment Management Authority joined forces to assess the health of a highly valued creek near Morwell.

Sharing understanding

Waterhole Creek near Morwell in the Latrobe Valley is valued by the local community as a place for recreation as well as for its plants and animals. It’s also a significant cultural site.

Because of its importance, the EPA chose Waterhole Creek as a project in its Citizen Science Program in 2017. The EPA and the local community shared their knowledge and expertise to understand the health of the creek.

Citizens for science

As citizen scientists, community members were involved in both designing the project and in collecting data.

Locals knew good places to take water samples from, and they were also aware of possible pollutants in the water because of the way land had been used in the past.

The EPA then trained the citizen scientists in water monitoring. Every fortnight for six months they took water samples from 10 different places around the creek. They collected data on:

  • water temperature

  • pH

  • turbidity (how clear or cloudy the water is)

  • electrical conductivity

  • levels of ammonia.

The data showed that the water quality is typical of a waterway in this sort of area, surrounded by mixed land use. For example, water quality tended not to meet standards nearer the town centre. The following metals were found in concentrations higher than guidelines:

  • zinc at 7 monitored sites

  • lead at 1 monitored site

  • nickel at 1 monitored site

  • mercury at 1 monitored site.

Next steps

The data collected gives the EPA a ‘baseline’ measure. This means they will be able to understand the scale and possible causes of future water quality issues by comparing future measurements to the 2017 data.

The community will continue to work towards protecting and managing the creek, with support from the EPA, and may create a formal group.

Discover more

Healthy fish, sustainable stocks

A program to monitor fish populations and river health is providing both scientists and fishers with valuable information on the location and condition of native fish in Victorian rivers.

Report cards for native fish

Conservationists and recreational fishers now have access to information about the health of Victoria’s rivers and the status of native freshwater fish – thanks to online Native Fish Report Cards.

Using data collected by scientists and anglers on the number and size of fish caught in a particular river, the Native Fish Report Cards give a snapshot of the health and population of selected fish. This includes both fish that recreational fishers are allowed to catch and threatened species. The snapshot helps improve fisheries management and also tells anglers where recreational fish are biting.

A combined effort

The Native Fish Report Card Program is a partnership between the Department of Environment, Land, Water and Planning (DELWP) and the Victorian Fisheries Authority, with input from recreational fishing license holders. It forms part of Water for Victoria, the state’s plan for managing water in response to climate change impacts and population growth.

Fish species are being monitored at 10 priority rivers, with more to be added in the future. Population data will be collected over a three-year period, with the report cards updated annually.

The report cards can be seen at the Native Fish Report Card website, which includes a mapping portal and downloadable summaries for each species in each priority river. The website also provides other resources about waterway health and recreational fishing.


Discover more

Water bugs on drugs

Popping a pill can save a life, but powerful chemicals are getting into our waterways and their animal inhabitants.

The negative effects of meds

Pharmaceutical use is increasing globally, with billions of people taking drugs to save and improve their lives. The benefits of taking these medications are so great that their potential negative consequences are often overlooked. But what makes humans better has the potential to harm a range of other creatures.

When people take pharmaceuticals, our bodies do not always take up all of the drug. We excrete the excess,  which ends up in the sewerage system. As water treatment facilities are not usually designed to remove the chemical compounds in pharmaceuticals, the excess ends up being discharged into our rivers, streams and oceans.

Starting to study

An international team of scientists, including two from Victoria’s Monash University, detected pharmaceutical compounds in invertebrates in six streams near Melbourne, and published the results in Nature Communications in 2018.

The team sampled more than 190 invertebrates and found pharmaceuticals in every one of them. They found 69 different drugs in the bugs, including common medicines such as non-steroidal anti-inflammatories and antidepressants. One of the waterways – a stream in a national park – was thought to be pristine, but even here pharmaceuticals were found in the bugs, although in lower concentrations than other sample sites. This suggests that very few waterways are drug-free.

Drugs up the food webs

Not much is known about the drug movement through aquatic food webs (a complex network of many food chains).

The scientists calculated the doses that aquatic vertebrates such as platypus and brown trout could be consuming as they fed on the medicated bugs. They estimated that some animals, for example a platypus living in a creek receiving wastewater, could be exposed to as much as half an adult human dose of some types of drugs, such as antidepressants.

Scientists have yet to discover what effect taking these drugs might have on both the invertebrates and their predators.

Discover more

Why fish need trees

With aquatic biodiversity threatened by climate change, water use and intensive land use, trees can help improve water quality in streams and protect Victoria’s fish.

Data driven understanding

A group of Victorian scientists used data from 20 years of biological monitoring — from 1990 to 2009 — to see how climate and the amount of vegetation around water catchments affected the numbers and types of fish in Victorian waterways.

The scientists, from EPA Victoria, Arthur Rylah Institute and Monash University, also wanted to identify land-management practices that might help lessen the negative effects of climate change on freshwater ecosystems.

Fewer trees means fewer fish

The data showed that water quality in streams was consistently better if they had upstream catchments with extensive native tree cover, as well as intact vegetation on and in the adjacent wetlands. In those streams, better water quality resulted in larger and more diverse fish populations.

The amount of vegetation around catchments influences a range of factors, including:

  • supplies of water, energy (light and organic matter), nutrients and sediments to running water habitats

  • channel form and habitat structure

  • population dynamics for species with non aquatic life-stages.

This was true even during severe drought.

Protecting our aquatic ecosystems

Climate scientists expect we will experience reduced rainfall or increased variability in rainfall in the future, as well as more frequent and intense weather events such as droughts. All of this will mean reduced water flow in rivers and streams, resulting in lower quality water and a loss of aquatic habitat for fish and other animals.

The data clearly showed that, in these important ecosystems, vegetation around waterways, especially catchments, has a positive effect on water quality. Carefully managed planting of native trees and other vegetation might protect the animal and plant life of Victorian waterways from the worst impacts of climate change.