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Government of Western Australia Department of Water and Environmental Regulation
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Planning for the future Show Sub Nav
Finding water

Finding new water resources, including Royalties for Regions-funded programs and other drilling programs to explore resources across the state.

Water allocation plans

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Rural water support

Click here to apply for rebates and grants for farmers, pastoralists and rural communities to improve local water supplies and for information about assistance to help farmers access water during dry seasons.

Flood planning and mapping

Information, advice and management of flood plans based on flood behaviour research and floodplain mapping for the state's major rivers.

Water and land use planning

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Meeting demand

Information about how we work with government, water service providers, industry and communities to identify water demand management and supply options that enable sustainable water use.

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Water licensing Water Licensing

Licences and how to apply, licensing policies, forms to download and answers to questions frequently asked by current and prospective licensees.

Water trading Water Trading

Find out who is eligible to trade water entitlements and how applications are assessed. Click here to identify potential trading partners from the Water Register.

Metering and measurement

Metering and measuring the water you take helps you understand your water usage to make the most of your entitlements and reduce your overall costs.

Water licensing fees

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Current legislation

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Water reform

We are updating our policy and legislation to deliver water resource management legislation that is flexible, progressive and capable of managing water today and in the future.

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Water services Water Services

Legislation and policy for Western Australia’s water service providers.

Urban development Urban Development

Planning and managing water to enable growing, liveable water smart towns and cities.

Recycling and efficiency Recycling

Information about wastewater recycling, water efficiencies and the use of fit-for-purpose water. Recycling is encouraged whenever it is socially, economically and environmentally acceptable to make smart use of waste water for the ongoing development of the State.

Bores Domestic Garden Watering

For information on groundwater, garden bores and waterwise gardens please visit our Be Groundwater Wise website. You can find questions and answers about garden bores,

Drinking water Mundaring Weir

Protecting and managing public drinking water source areas including policies relating to public drinking water source areas, water source protection plans, water quality strategies and management and review processes.

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Groundwater Ground Water

Information on the state’s groundwater resources, locations, investigations, aquifer recharge and sustainable management of water resources, including an overview of state groundwater investigations.

Surface water Surface Water

Surface water, like rivers and streams used for public water supply, self-supply, irrigation, recreation and hydropower and rainfall and streamflow monitoring, catchment modelling and flood studies to manage surface water.

Water quality Water Quality

Click here for information about water quality, including public drinking water source areas, salinity, brochures, fact sheets and best management practices for various land uses and activities to help protect water quality and public health.

Waterways Rivers and Estuaries

Rivers and estuaries and their importance including information on monitoring and assessing waterways, protecting, understanding, planning, restoring, and risks and threats.

Estuaries

There are 166 estuaries in Western Australia as established through the National Land and Water Resources Audit (NLWRA) 2000, where an estuary is defined as

Onshore petroleum and water resources 5.6 Shale_and_tight_gas.jpg

Information on the department’s role in relation to the shale and tight gas industry.

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Maps

Monitoring and data

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  • Water topics
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  • Threats to our waterways
  • Eutrophication (nutrient enrichment)
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    • What are waterways, rivers, estuaries and wetlands?
    • Values of our waterways
    • Threats to our waterways
      • Eutrophication (nutrient enrichment)
      • Contaminants
      • Acid sulphate soils
      • Algal blooms
      • Fish kill events
      • Climate change and waterways
      • Altered flow regimes
      • Barriers to aquatic connectivity
      • Erosion and sedimentation
    • Assessing waterway health
    • Managing our waterways
    • Vasse Geographe Strategy
  • Estuaries
  • Onshore petroleum and water resources
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Eutrophication (nutrient enrichment)

Eutrophication, is nutrient enrichment; it drives excess primary productivity in waterways.  It can be either natural or caused by human impact.

Humans alter the way water moves through the landscape by clearing vegetation for agriculture or urban development and by constructing drainage that moves water quickly off the landscape into the receiving water bodies. These changes to the landscape mean that there is often insufficient vegetation around rivers and estuaries to utilise excess nutrients. This problem is exacerbated when extra nutrients are added onto the land in the form of fertiliser and animal manure, or also by changing the types of plants present.

Compounds that contain nitrogen and phosphorus are the most common culprits driving eutrophication. These nutrients are generally not toxic at the concentrations typically found in nature, however they can have a large impact on the health of rivers and estuaries. For example, high concentrations of nutrients may encourage algal growth and result in nuisance or toxic algal blooms.

Eventually these blooms will collapse and die and the resulting decomposition of the algal cells will strip oxygen out of the water, sometimes causing fish kill events.

Nutrients are also temporarily stored in the sediments of rivers and estuaries, but under certain environmental conditions, such as low oxygen, the nutrients can re-enter the overlying water and be available again to grow more algae.

The Department of Water assesses the concentrations of nutrients in a variety of water bodies including river and estuary systems, stormwater drains and groundwater. Understanding the concentrations of nutrients both within and entering our rivers and estuaries will assist the department in assessing the health of waterways and in determining management solutions for impacts such as algal blooms and fish kill events.Nutrient enrichment in the Peel catchment

Long term monitoring allows us to assess trends in nutrients in our freshwater and estuarine systems. This allows us to assess and report whether nutrient conditions are improving or degrading (for example see catchment nutrient reports and the State-wide River Water Quality Assessment). We can also use this data and our knowledge of land use to construct models, which help us predict where nutrients are being exported from the landscape.

These models also allow us to target remediation works to ensure the best results are obtained and are an integral part of our water quality improvement plans.

Further information

The water quality information collected by the Department of Water and other organisations is available from the department's Water Information Reporting portal.

For further information see monitoring and assessing water quality and managing water quality and the following publications:

  • Nitrogen and phosphorus cycles (River Science Issue 4)
  • Sources of nutrients to the Swan and Canning rivers (River Science Issue 5)
  • The delivery of nutrients to the Swan and Canning rivers has changed over time (River Science Issue 6)
  • Seasonal nutrient dynamics in the Swan Estuary: 1995-2000 (River Science Issue 8)
  • Seasonal nutrient dynamics in the Canning River and Estuary (River Science Issue 9)
  • Field sampling guidelines : a guideline for field sampling for surface water quality monitoring programs
  • Water quality monitoring program design: a guideline to the development of surface water quality monitoring programs
Page last updated - 07 Apr 2015
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The Department of Water and Environmental Regulation was established by the Government of Western Australia on 1 July 2017. It is a result of the amalgamation of the Department of Environment Regulation, Department of Water and the Office of the Environmental Protection Authority. This website/publication may contain references to previous government departments and programs. Please contact the Department of Water and Environmental Regulation to clarify any specific information.

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