Alkimos seawater desalination plant investigations

Artists impression of future Alkimos Seawater Desalination Plant

As part of our long term planning to secure Perth’s water supply, we have completed feasibility investigations and have commenced environmental approvals for a seawater desalination plant at Alkimos. The Alkimos Seawater Desalination Plant is one of a number of water source options being considered, with a decision on when a new source may be needed for Perth dependent on a range of factors, including population growth, climate and demand.

What we investigated?

  • A seawater desalination plant with capacity to treat 25 billion litres of seawater per year, with a possible future expansion
  • Two new ocean pipelines, below the seabed, that bring seawater into and take brine (salty water) away from the plant
  • A water transfer pipeline to take water from Alkimos to Wanneroo, where the water will be connected to Perth’s water supply
  • Understanding environmental impacts
  • Working with the community to understand its needs.

We are also investigating a co-located groundwater treatment plant to be incorporated within the Alkimos Water Precinct.

You can read more about the investigations here.

Working with the community

We invited members of the Alkimos and surrounds community to be a part of our investigations. You can read more about our conversations with community here .

We also met with dozens of stakeholders, with feedback received reflected in our investigations.

We will continue to keep the community and stakeholders updated as we progress our planning.

Protecting the marine environment

Extensive research has been conducted to ensure the offshore pipelines required to bring seawater in and take brine away from the plant are located and constructed with the least possible environmental impact.

You can read more about how we are planning to protect the marine environment here.

Impacts on the local community

A priority of our investigations is minimising disturbance to surround homes and businesses during plant construction and operations. You can read more about how we have designed the plant to reduce noise and screened it from homes here.

Pipeline to Wanneroo Reservoir

Water from the plant will join Perth’s water supply through a 35km pipeline. You can read more about the pipeline here.

Have your say and register to stay updated

You can have provide feedback on the proposed plant or register to keep updated by emailing community.engagement@watercorporation.com.au

By registering your details, you can stay informed and continue to input feedback as we progress in the approval process.

As part of our long term planning to secure Perth’s water supply, we have completed feasibility investigations and have commenced environmental approvals for a seawater desalination plant at Alkimos. The Alkimos Seawater Desalination Plant is one of a number of water source options being considered, with a decision on when a new source may be needed for Perth dependent on a range of factors, including population growth, climate and demand.

What we investigated?

  • A seawater desalination plant with capacity to treat 25 billion litres of seawater per year, with a possible future expansion
  • Two new ocean pipelines, below the seabed, that bring seawater into and take brine (salty water) away from the plant
  • A water transfer pipeline to take water from Alkimos to Wanneroo, where the water will be connected to Perth’s water supply
  • Understanding environmental impacts
  • Working with the community to understand its needs.

We are also investigating a co-located groundwater treatment plant to be incorporated within the Alkimos Water Precinct.

You can read more about the investigations here.

Working with the community

We invited members of the Alkimos and surrounds community to be a part of our investigations. You can read more about our conversations with community here .

We also met with dozens of stakeholders, with feedback received reflected in our investigations.

We will continue to keep the community and stakeholders updated as we progress our planning.

Protecting the marine environment

Extensive research has been conducted to ensure the offshore pipelines required to bring seawater in and take brine away from the plant are located and constructed with the least possible environmental impact.

You can read more about how we are planning to protect the marine environment here.

Impacts on the local community

A priority of our investigations is minimising disturbance to surround homes and businesses during plant construction and operations. You can read more about how we have designed the plant to reduce noise and screened it from homes here.

Pipeline to Wanneroo Reservoir

Water from the plant will join Perth’s water supply through a 35km pipeline. You can read more about the pipeline here.

Have your say and register to stay updated

You can have provide feedback on the proposed plant or register to keep updated by emailing community.engagement@watercorporation.com.au

By registering your details, you can stay informed and continue to input feedback as we progress in the approval process.

  • Survey work

    On Thursday 11 February 2021, our authorised consultant Jacobs, is undertaking survey work at the Alkimos Water Precinct. This survey work will continue until approximately Friday 26 February 2021. Work will be carried out between 7.00am and 5pm on weekdays.

    We are investigating ground conditions for enabling infrastructure and surveys for access road improvements. Whilst no decision has been made yet on the future of the possible Alkimos Desalination Plant, preparing to undertake enabling works early will minimise disruption to the current and future local community and road users.

    All work will be carried out within Water Corporation owned land at the Alkimos Water Precinct. All Water Corporation employees and contractors endeavour to minimise disruption where possible.

    Residents may notice an increase in noise and activity in the area during work hours. We thank you for your understanding and cooperation while this important work takes place.

    For more information phone (08) 9420 2130 or email community.engagement@watercorporation.com.au.

  • Environmental approvals update

    Department of Agriculture, Water and the Environment Approval Update

    The Department of Agriculture, Water and the Environment has recently determined that Alkimos Water Desalination Plant is a controlled action and therefore will require assessment and approval under the EPBC act.

    For further information on this decision visit http://epbcnotices.environment.gov.au/referralslist/ - Reference 2019/8453.

    Environmental Protection Authority Approval Update

    Water Corporation has also received confirmation from the Environmental Protection Authority that Alkimos Water Desalination Plant will be required to be assessed under the EP Act.

    All interested parties have the opportunity to comment during the public comment. More information on the referral and how to provide comment is available here http://www.epa.wa.gov.au/proposal-search(External link), referral number 2210.

    We will provide further confirmation on the timing of the comment period over the coming months.

  • Meet the team at the Butler Community Centre

    CLOSED: This discussion has concluded.

    We will be joining Public Transport Authority and other government departments and agencies at the a Yanchep Rail Extension Community Drop In Session on Saturday, September 5 from 1pm to 4pm at the Butler Community Centre.

    Come visit the Water Corporation stall to learn about our plans for Alkimos or for some great waterwise information and tips.

    You can also call us anytime by contacting Community Engagement via email to community.engagement@watercorporation.com.au or phoning 9420 2883.

  • Meet the Team: Alkimos Gateway Street Fair – 26 October 19

    CLOSED: This discussion has concluded.
    We will be joining Lendlease and other government departments and agencies at the Alkimos Gateway Street Fair on Saturday, 26 October from 11am to 3pm. Come visit the Water Corporation stall to learn about our plans for Alkimos or for some great waterwise information and tips.

    You can also call us anytime by contacting Community Engagement Senior Advisor Jessica Moloney-Christie via email to community.engagement@watercorporation.com.au(External link) or phoning 9420 2883.

  • Public comment period opens under Commonwealth EPBC Act

    CLOSED: This discussion has concluded.

    The Water Corporation referred the Alkimos Seawater Desalination Plant proposal under the Environment Protection and Biodiversity Conservation Act 1999. The proposal is now open for comment on the Department of Environment and Energy website for a period of 10 business days.

    You can read our referral here: http://epbcnotices.environment.gov.au/publicnoticesreferrals. Reference 2019/8453

    Public comment will close on 14 August 2019.

    For information on how to make a public comment on a referral, please see the EPBC Notices Homepage



  • Level of Assessment Announced by Regulator

    CLOSED: This discussion has concluded.

    The Environmental Protection Authority has announced it will assess the Alkimos Seawater Desalination Plant proposal at the level of Public Environmental Review.

    More information on the determination can be found at the EPA webpage.

  • Project update –Seawater Desalination Plant proposals open for public comment

    CLOSED: This discussion has concluded.

    The Environmental Protection Authority (EPA) is inviting public comment on the referrals for the Alkimos Seawater Desalination Plant and Perth Seawater Desalination Plant 2.

    The seven day public comment period is one of the first stages of the EPA process, where the public can provide input on whether the proposal should or should not be assessed.

    Public comment on the proposals is open until 20 May, 2019.

    You can read more about the referral process here.

    To view details of the proposals visit the EPA consultation hub here.


  • Water Corporation refers desalination options for environmental approvals

    CLOSED: This discussion has concluded.

    Following more than 18 months of feasibility investigations, supported by stakeholder and community engagement, the Water Corporation has referred two desalination plant proposals to the Federal Department of Environment and Energy (EPBC Act) and the Western Australian Environmental Protection Authority for assessment.

    The proposals: Alkimos Seawater Desalination Plant and Perth Seawater Desalination Plant 2 (in Kwinana), are part of long term planning to secure Perth’s water supply, with current planning indicating a new water source may be needed for Perth within the next 5-10 years.

    To learn more about the proposals and stay updated as assessments progress, including period of public comment, visit: https://yoursay.watercorporation.com.au/future-perth-desalination-plants.

  • Marine Update - February 2019

    CLOSED: This discussion has concluded.

    Completion of offshore investigations

    Water Corporation has completed its Alkimos offshore investigations and will now demobilise the marine jack-up barge from the Alkimos area.

    The Corporation thanks the Alkimos community and marine stakeholders for their patience during the work, which is being considered as part of feasibility investigations for a seawater desalination plant at Alkimos.

    The barge will commence its journey to Henderson when conditions are favourable, depending on conditions this could take upwards of 3 weeks.

    Wastewater Treatment Plant Ocean Outfall maintenance

    In coming weeks the Corporation will complete maintenance work on the Alkimos Wastewater Treatment Plant ocean outfall.

    The work is planned for completion over 2-3 days, pending weather conditions and will involve divers and a vessel being positioned above the pipeline. Flags and required signage will be in place to advise other vessels to the work.

    Operation of the wastewater treatment plant will not be interrupted during the work.

    For more information phone 9420 3488 or email community.engagement@watercorporation.com.au.


  • Project update - 4 February 2019

    CLOSED: This discussion has concluded.

    As part of our long term planning to secure Perth’s water supply, we are nearing the completion of feasibility investigations, and will soon seek environmental approvals, for a seawater desalination plant at Alkimos.

    Thank you to the hundreds of people who attended community events in 2018 or provided feedback online. We value your input, it has allowed us to address community interests and concerns in our planning.

    The Alkimos Seawater Desalination Plant is one of a number of options being investigated to secure Perth’s water supply for the future, which also includes investigating a second seawater desalination plant in Kwinana. While we may not need a new water source for five to ten years, communicating with you along the way is important to us.

    You can find out more about our investigations and share your feedback with us by completing a short survey. By completing the feedback survey and registering your details with us, you can stay informed as the project progresses.


Page last updated: 06 October 2021, 11:54