Alkimos seawater desalination
plant project

Work is underway to build the Alkimos Seawater Desalination Plant within the Alkimos Water Precinct. We've begun electrical work and excavation to prepare for underground tunnelling towards the ocean. This has involved excavating, earthmoving, concreting, and crane operations. Rock breakers have also been used on hard limestone rock inside the tunnel access pit.

As approved by the City of Wanneroo, from Monday 6 January 2025 to the end of March 2025, we will complete some necessary construction activities outside of regular working hours.

What to expect:

• Continuous, 24-hour work including Sundays and public holidays.
• While we don't anticipate that nearby residents will be impacted, however you may notice on-site light, noise, and activity.
• You may also notice additional truck movements accessing the site form Brindabella Drive.

We thank you for your ongoing patience while we complete this essential work.

Work is currently underway for the new Alkimos Seawater Desalination Plant.

We've been using piling machines to drill holes and fill them with concrete to act as in underground retaining wall. This work involves loud banging, as the machine moves back and forth to remove dug up soil.

This piling work was planned to be completed by the end of October, however due to ground conditions and weather, it will now be completed by late November 2024.

With the approval from the City of Wanneroo, we will continue piling from 7am Monday to 7pm Saturday, with a rest day Sunday until the piling work is complete. Extended working hours will help us to deliver the plant on time in 2028.

We understand that this work is noisy for some residents. We apologise for any inconvenience and thank you for your patience while we complete this essential work.

Additional overnight work and Sunday work

Additional overnight work and occasional Sunday work for lower impact construction activities, that will not include piling, has also been approved by the City of Wanneroo between now and Tuesday 24 December 2024. We'll keep you updated on out of hours work as the project progresses.

Our project team will continue to monitor noise and reduce impacts where possible.

We're working with Western Power to supply electricity to the Alkimos Water Precinct. Western Power's authorised contractor, LS Cables, will construct a 5km underground transmission line from their Yanchep Substation near Wanneroo Road.

Start of work

Construction is planned to take place from around late October 2024 until late 2025 and will be completed in three stages.

Stage 1 will take place along Romeo Road, between Wanneroo Rad and Marmion Avenue. This will involve installing conduit, which is a plastic sleeve underground, that the new transmission line will be installed into.

For more information about these stages, including estimated timeframes please visit the project website.

Work is underway for the new Alkimos Seawater Desalination Plant.

To keep to schedule, we will now be completing work outside of our regular working hours by adding overnight work. From Thursday 1 August 2024 work will occur continuously, with no work on Sundays. The new working hours will occur from 7am Monday to 7pm Saturday

Preparation work on the Alkimos Desalination Plant is progressing to the next phase, and portions of the site are now being handed over to theAlkimos SeaWater Alliance (ASWA). Our authorised contractor, Georgiou Group, will continue construction along the western berm, on a vegetated dune between the Alkimos Water Precinct and a future Development WA project.

For safety reasons, Georgiou will now be accessing the area via Graceful Boulevard, past the roundabout at Marginella Boulevard.

• To minimise traffic impacts, deliveries via heavy vehicles will occur outside of peak times via Route A (Brindabella Parkway and Pectoral Promenade) where possible.

• Route B (Graceful Boulevard, between Marmion Avenue and Pectoral Promenade) may be used as an alternate route, if required.

• You may notice increased activity along Graceful Boulevard between Marimon Avenue and Marginella Boulevard, consisting of Georgiou light vehicles, and 2 to 6 heavy vehicle deliveries per day.

• Access to the Alkimos Water Precinct via Graceful Boulevard will begin in mid July 2024 and continue through to early 2025.

• We will also access the Eglington bore area near Graceful Boulevard over the coming weeks to complete pump testing.

You may notice increased activity at this location during this time. A map of the work area can be seen below. For more information about the Alkimos Seawater Desalination Plant, please visit out website.

A new telecommunication tower will be constructed towards the Eastern boundary of the Alkimos Water Precinct in June 2024. This is to allow the currenttower to be decommissioned as it sits within the parcel of land where the plant will be constructed. The new tower is the same size as the current tower (60m) however it will sit on higher ground within the site so may appear slightly taller.

Over the next six months, works will be completed to upgrade the electrical supply to the new tower.

During this time, the old tower will need to remain in place. In early 2025, the original tower will be decommissioned and removed from the site.

To inform detailed design of the Alkimos Seawater Desalination Plant, we are currently completing drilling investigations 500m - 3.5km offshore of Alkimos Beach until late-May.In addition to this, we are now planning to complete geophysical surveys including low volume seismic testing for a period of 6 days from 22 April.

During this survey you may notice a catamaran with equipment attached to the hull or being towed behind the vessel through the area. Streamers behind the vessel will range from 20-100m in length and will traverse the area typically adjacent to the coast. A 100m exclusion zone will remain in place throughout this work to ensure the safety of everyone.

As the scale and duration of the survey is small, no adverse impacts to the surrounding marine environment are expected. Equipment has been specifically selected to minimise any potential risks to marine life. While the underwater noise levels are low, these works have been bought forward as a precautionary measure to occur outside of whale migration season.

We have now awarded the contract for design, construction and operation of the Alkimos Seawater Desalination Plant to Acciona and Jacobs Group.

The two contractorswill form an alliance known as the Alkimos SeaWater Alliance, working in partnership with Water Corporation to deliver the first 50 billion litres per year plant.

To inform detailed design and support delivery of the ocean intake and discharge pipelines with minimal environmental impacts, we need to gather further detail regardingthe seabed conditions. A jack-up barge, marine drill rig and small support vessel will be visible around 500m-3.5km offshore of Alkimos Beach from around 2 April 2024. Work to collect seabed samples will occur during daylight hours for up to nine weeks. This factors in additional time for adverse weather conditions and a week to mobilise/demobilise either side of the works. A temporary marine exclusion zone will be set up to ensure everyone’s safety. A comprehensive marine management plan has been prepared, and no adverse impacts to the marine environment are expected during this work. Access to Alkimos Beach and the Alkimos and Eglinton wrecks will not be affected. Some noise may be heard at times during the drilling work.

To provide potable water to the plant, our authorised contractor Georgiou Group is constructing a water pipe to the Alkimos Water Precinct, connecting from theexisting network on Marmion Avenue.

The pipe will be constructed by tunnelling under Marmion Avenue, and open trench in the southbound lane and verge of Marmion for the final connection.

To complete the tie in connection safely, we will need to close around 120m of single southbound lane on Marmion Avenue between Modernism Avenue and Brindabella Parkway. Traffic management will be in place for approximately 5 weeks in mid-March / mid-April.

As a result of recent enquiries regarding kangaroo sightings around the Alkimos Water Precinct, we are making the following changes to the temporary fencingon Graceful Boulevard and Pectoral Promenade:

• A temporary access point has been installed along Pectoral Promenade.
• In the coming days, our authorised contractor Georgiou Group will relocate part of the temporary fence further within our site footprint. This will provide a vegetated space for wildlife outside the fence, away from the road and public interaction. This will also reduce visual impacts of the fence, for the local community.
• These works will occur between the hours of 7am and 7pm weekdays to minimise disturbance to residents nearby.

We have recently been contacted by members of the Alkimos community about kangaroo sightings in the area around Water Corporation’s Alkimos Water Precinct (the Precinct).It has been suggested that our temporary fencing along Graceful Boulevard and Pectoral Promenade, installed in November last year, is preventing kangaroos from entering and exiting the Precinct. The fencing is in place for the safety of the community and the security of the construction site.

We have since reached out to the relevant authority for more information about kangaroos in the area. We have been advised that it is normal to see an increase in kangaroo movements at this time of year as they forage for food and water during hot periods. There are existing access points for kangaroos to move in and out of the vegetated areas on the northern side of the Precinct.

It is recommended that members of the community do not approach kangaroos as this will cause distress. If the kangaroo is left alone, it is capable of making its own way back into the Precinct. In response to recent enquiries, we are reviewing options to change the alignment of the temporary fencing to provide a wider vegetated buffer from vehicles and public interaction. We are also arranging signage to be installed on the fence to indicate the contact details for Water Corporation’s contractor Georgiou Group, who have a qualified fauna handler available to assist as required.

If there are further concerns regarding kangaroos or other wildlife along the fence line, please contact them on 0408 036 578. Water Corporation completed extensive environmental investigations and works to support environmental approvals for the Alkimos Desalination Plant.

This incorporated careful consideration towards minimising the plant footprint to preserve environmental conservation areas and native vegetation. These areas will continue to be managed during and after construction providing valuable ecological habitat for native wildlife. We expect this will become increasingly important as further development occurs outside the Water Corporation site.

A preferred proponent has been selected for the design, construction and operation of the future Alkimos Seawater Desalination Plant.

Pending successful negotiations, Acciona and Jacobs Groupwill form an alliance which will be known as the Northern Water Partnership.

• Acciona brings considerable experience in delivery and operation of drinking water infrastructure, having previously built and now operating the Adelaide Seawater Desalination Plant.

• Jacobs has similar expertise, having partnered with Water Corporation to deliver vital water supply and wastewater projects across Western Australia.

Award of the contract is due to occur in March, with construction of the plant to commence mid-2024.

07 Dec 2023

Water Corporation has commenced works to prepare the site for the future Alkimos Seawater Desalination Plant.

The following activities will be completed ahead of plantconstruction which is scheduled to start mid-2024:

• Earthworks to reduce the ground level to lower the site into the landscape.

• Construction of a retaining wall and sand dune to shield the plant from the coast.

• Installation of temporary perimeter fencing, demountable offices, and connection to water for construction activities.

These works will occur within Water Corporation’s site at the Alkimos Water Precinct. As there is a buffer area separating the site from residential areas, it’s expected that construction impacts including noise and dust will be minimised as much as possible.

10 Nov 2023

Following a rigorous assessment, Water Corporation has received State and Commonwealth environmental approval for the Alkimos Desalination Plant.

The approvals is subject to Ministerial conditions whichstipulate how Water Corporation will deliver and operate the plant and associated infrastructure with appropriate management of terrestrial and marine environments.

The project was granted development approval in September by an independent Development Assessment Panel, and enabling works, including earthworks are expected to start on site in the coming weeks. Construction of the major infrastructure is expected to commence in 2024, with completion in 2028.

10 Aug 2023

The Western Australian Minister for Environment (Hon. Reece Whitby MLA) has decided that the Alkimos Seawater Desalination Plant (ASDP) proposal can be implemented subject tothe conditions outlined in Ministerial Statement 1207. The conditions are consistent with those recommended by the Environmental Protection Authority (EPA) in Report 1739.

You can find the EPA Assessment Report and Ministerial Statement on the EPA’s website 

The ASDP proposal is awaiting approval under the Commonwealth Environmental Protection and Biodiversity Conservation (EPBC) Act 1999. A separate approval decision will be issued by the Commonwealth.

24 May 2023

The Environmental Protection Authority (EPA) today released its assessment report on Water Corporation's Alkimos Seawater Desalination Plant proposal.

The assessment report has been prepared by theEnvironmental Protection Authority (EPA) under s.44 of the Environmental Protection Act 1986 (WA). It describes the outcomes of the EPA's assessments of the proposal. The EPA has recommended that the proposal may be implemented subject to conditions recommended in Appendix A of the assessment report.

You can read the Assessment Report 1739 on the EPA's website via https://www.epa.wa.gov.au/epa-assessment-reports.

10 March 2023

Water Corporations authorised consultants are undertaking marine investigations offshore of Alkimos between March 10 and 20, 2023. A large vessel will be in the area and lobster pots are a snagging risk. We respectfully request that lobster pots are removed from the area before work starts on the March 10. Lobster pots can be replaced from March 20, 2023 (which is when the vessel is expected to have left the area). We apologise for the inconvenience and thank you for your cooperation.

28 February 2023

Water Corporation invites organisations with suitable experience, capability, and capacity to submit a Registration of Interest for the ASDP Enabling Earthworks Project.

Bid Invitation Number - 70000013699

6 February 2023

Late last year, Water Corporation's authorised consultants Advisian and its contractor MES carried out investigations off the coast of Alkimos. Our consultants will return to the area to complete a small section of work that they were unable to complete during the previous campaign. Work will take place for approximately three days between February 20 and 27, 2023 during daylight hours.

30 January 2023

Come down to Oceans 27 927 Portside Promenade, Alkimos) on Thursday 9 February from 10 AM to 12 PM. Say hello to us and you may receive a coffee voucher (numbers limited)!

17 November 2022

Water Corporation's authorised consultants Advisian and its contractor MES will undertake geophysical investigations off the coast of Alkimos from 21 November 2022 for approximately one week.

The information is critical to inform the location and construction of the intake and outfall pipelines. Please refer to the information sheet for more information.

1 September 2022

Drinking water produced by the proposed Alkimos Seawater Desalination Plant will be transferred via a 33-kilometre below-ground pipeline to Wanneroo Reservoir where it will join Perth’s water supply.

Water Corporation and its contractors will undertake feature surveys and service location works along the pipeline alignment. The service identification will involve a vacuum excavation truck and you may notice PVC pipe left in place. The surveys will be in the road reserve and public open space and we will not need to enter private property. The surveys will be completed by mid-November 2022.

15 September 2022

Water Corporation referred the proposal for the Alkimos Seawater Desalination Plant to the Commonwealth Department of Climate Change, Energy, the Environment and Water and the Western Australian Environmental Protection Authority (EPA) in 2019. A detailed Environmental Review Document (ERD) is being assessed by the EPA. The EPA will consider submissions as part of its assessment process. The four-week public comment period starts on 28 September and will close on October 25, 2022. Copies of the ERD may be downloaded from www.epa.wa.gov.au (scroll down, click on 3. Assessment and then Environmental Review).

Hard copies are available for examination at the Wanneroo, Clarkson and Yanchep/Two Rocks Public Libraries. A limited number of hard copies are available on a first-come, first-served basis from Water Corporation Reception at 629 Newcastle Street, Leederville. Please telephone (08) 9420 2479 to ensure availability.

A new desalination plant north of Perth has long been considered as an option to provide safe, secure drinking water to our growing city.

Other locations were investigated, however, Alkimos was selected due to the site’s suitability to accommodate a new desalination plant with minimal impact. The site already has a wastewater treatment plant on what will become known as the future Alkimos Water Precinct.

To support a healthy groundwater system, we will also draw less groundwater from Perth’s north. It makes sense economically and practically to deliver a replacement source in the same area. 

A seawater desalination plant is a vital state asset and requires significant investment.

In 2021, the WA Government announced it had included $1.4 billion in the State Budget towards Perth’s next desalination plant.

We already operate two advanced desalination plants. Over the past five years on average, these provided around half the drinking water to homes and businesses across Perth.

Today, there are six large-scale drinking water desalination plants in Australia. Two are right here in WA, and one in Queensland, New South Wales, South Australia, and Victoria. Desalination is used in 120 countries around the world due to its efficiency and sustainability as a safe water source.

The plant will be built on Water Corporation land and have a buffer zone around it. Based on community feedback, the plant will be sunk into the site. Large, vegetated sand dunes will be built to shield it from view and reduce potential noise.

Other noise reduction measures such as cladding and acoustic louvres will be used.

A previous study found background noise from traffic on nearby Marmion Avenue was louder than what is expected from the plant.

Energy use at ASDP will be mitigated primarily through design efficiencies and energy recovery technologies. The expected plant performance will match or exceed industry benchmarks for energy efficiency.

Find out more

We began consultation with the local community in 2018.

We’ll continue to update the community as the project progresses. Please subscribe for email updates.

A groundwater treatment plant will be built at the Alkimos Water Precinct to treat water from up to three local bores. Treated water from the local bores will be combined with the desalinated water. During the desalination process, minerals are taken out of the water and the water is not drinkable. Adding the groundwater to the desalinated water will add minerals back into the water. This means that we will not need to add in chemicals, reducing costs and our environmental footprint.