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Government of Western Australia Department of Water and Environmental Regulation
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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.

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

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

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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.

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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.

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Current legislation for which the Department of Water assists the Minister for Water. Click here for current WA legislation.

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

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

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

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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.

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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

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

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Algal blooms

The term algal blooms may be used to describe macroalgae, which are large visible free floating or rooted plants, or microalgae which require a microscope to see but in mass are highly visible.Microcystis algal bloom Matilda Bay

Both macroalgae and microalgae (phytoplankton) are natural and desirable components of aquatic ecosytems.

Algal blooms are natural phenomena that occurred before human development in response to changes in temperature, light, rainfall, or changes in limiting nutrients.  Watershed clearing, agriculture and urban discharges, which add more nutrients, light and organic matter have led to increased frequency and duration of algal bloom and in some cases a switch to more toxic species.  Persistent and widespread blooms lead to loss of biological function of the waterway.

Extreme macrolagal growth can completely dominate an estuary or river such as in the Peel Harvey during the late 1980s and in the Oyster and Princess Royal Harbours.  In these cases macrolagal blooms shaded seagrasses and led to their loss or decline. In some cases phytoplankton can also dominate and cause ecosystem collapse. In the Peel Harvey in the 1990s the toxic phytoplankton Nodularia Spumigena replaced the macroalgae that had smothered the seagrasses.

We refer to nuisance algal blooms as those that discolour the water and which may leave residue on the skin of swimmers.

The term harmful algal bloom is used for those phytoplankton that sometimes produce toxins that affect either aquatic life, such as fish, or even human health.  Harmful algal blooms (HABS) are a global problem often in the areas of shellfish cultivation or aquaculture. Many of the produced algal toxins enter the shellfish and pose a serious human health risk leading to many deaths in Europe and the United States.

For natural waters, surveillance of phytoplankton is undertaken state wide in at-risk rivers and estuaries under the department's Statewide Algal Management Strategy. The Department of Water, in partnership with the Department of Health, has developed a statewide algal bloom response protocol.

We also work with Department of Fisheries in accordance with the Fish Kill Response protocol.

In the event of an algal bloom samples are collected and sent to the department's Phytoplankton Ecology Unit. Samples are analysed and the Department of Health is contacted if necessary. The Department of Health liaise with relevant local governments to issue a health warning when required.Blue-green algae bloom in the Narrows Lakes, Perth.

If you see an algal bloom please report it to:

  • the     Department of Water's ALGALWATCH 08 6250 8064 (officehours)
  • your nearest Department of Water office
  • the Department of Parks and Wildlife (for the Swan Canning Riverpark) on 9278 0900 or after hours on 0419     192 845.

For your safety:

  • Contact with some algal species can be     harmful for humans and pets - if you notice signs of an algal bloom it is     recommended that you and your pets do not go swimming.
  • Some species of algae produce a toxin     that can contaminate wild shellfish and make them unsafe to eat.
  • See the Department of Health website and see Algae: Blooms, Scum and Recreation.
For further information about algal blooms see:
  • Factors contributing to fish kills and algal blooms diagram
  • Weekly microalgae activity reports for the Swan Canning River
  • Algal blooms (Water facts 6)
  • Algal blooms in the Swan Canning Estuary: Patterns, Causes and History (River Science Issue 3)
  • Summer surprise - the Swan River blue-green algal bloom, February 2000 (River Science Issue 2)
  • Peel waterways centre fact sheets
Page last updated - 10 Jun 2022
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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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