Project overview

    What is the Refresh Vaucluse Diamond Bay Project?

    The Refresh Vaucluse and Diamond Bay project involves the design, construction, testing and commissioning of new wastewater infrastructure in the Vaucluse and Diamond Bay areas to re-divert untreated wastewater from three ocean outfalls to the Bondi wastewater treatment plant (WWTP). 

     The project will reduce the continuous flow of untreated wastewater into the ocean and address water quality and public health risks associated with the ocean outfalls. 

     We'll build new wastewater infrastructure to re-divert untreated wastewater from the ocean outfalls to the Bondi wastewater treatment plant. This includes:

    • two new wastewater pump stations - Parsley Bay car park and Eastern Reserve
    • a new 1.8 km wastewater pipeline from Parsley Bay to Dover Road via Carlisle Street, at a depth of up to 60m
    • new pipelines from Diamond Bay Reserve and Oceanview Avenue to the new pump station at Eastern Reserve 
    • new pipelines along Mitchell Road, Old South Head Road and Spencer Street, Rose Bay
    • upgrading the existing emergency relief structure on Ian Street, Rose Bay
    • wastewater infrastructure, including maintenance holes and ventilation shafts in Diamond Bay and Vaucluse.

    Why is Sydney Water undertaking this project?

    The wastewater system in the South Head Peninsula is different to other systems in Sydney. 

    A legacy from Sydney's early network, wastewater from the peninsula isn't treated. Instead, it flows directly into the ocean at three locations, via so-called 'ocean outfalls'. These outfalls, which were built between 1916 and 1936, are located at the bottom of the cliffs at Vaucluse, Diamond Bay and Dover Heights and discharge into a largely inaccessible part of the coastline.

    The Refresh Vaucluse and Diamond Bay project will reduce the amount of untreated wastewater discharged to the ocean. 

    Refreshing the wastewater system in Vaucluse and Diamond Bay offers multiple benefits—improving the harbour and coastal water quality, protecting the health of our community and the marine ecology.

    Is it safe to swim near the ocean outfalls?

    In 2018, Sydney Water released a Pollution Study Report, Vaucluse Diamond Bay Ocean Discharges, in response to the NSW Environmental Protection Authority's Pollution Reduction Program.

    Based on the information in the pollution study, we recommended that people avoid fishing, swimming or coming into contact with water near the three outfalls while we work towards refreshing the wastewater system to stop the continuous flow of untreated wastewater into the ocean.

    Where is the project currently up to?

    We’re progressing the detailed design and working with our delivery contractor, Comdain Infrastructure and WSP as well as relevant stakeholders, including council to optimise the design.

     In November and December 2021, we conducted geotechnical investigations around Dover Heights, Parsley Bay Beach and Rose Bay to gain further insights on the geological environment and existing utilities to inform the design of the project and our construction plans.

     Following these investigations, we have updated our designs, and have made some adjustments, which we will share with the local community for feedback. At this stage the detailed design is 50% complete and we’ll keep the conversation going as we continue to progress the design and the timing and staging of the construction work.

    How is Sydney Water consulting with the community and how can I have input into the project?

    We’re thankful for the ongoing support we receive from the community as we work together to reduce the continuous discharge of untreated wastewater into the ocean at Vaucluse, Diamond Bay and Dover Heights. 

    We began consulting with the community on this project in 2018 and will continue to consult with you throughout the upcoming project phases – detailed design, construction and operation.

    We welcome your feedback and encourage everyone to get involved in the conversation about our plans via Sydney Water Talk

    How can I receive updates on this project?

    Sydney Water is committed to keeping stakeholders informed and will provide accurate and timely information throughout the work. We will listen to your concerns and wherever possible act upon them.

    We welcome community feedback and enquiries on our projects and encourage everyone to get involved in the conversation about our plans via Sydney Water Talk 

    If you would like more information about the project, please call 1800 491 757or email

    What are the hours of work?

    Our standard working hours of work are:

    • Monday to Friday, 7 am to 6 pm
    • Saturday, 8 am to 1 pm

    No work is planned for Sunday and public holidays. 

     We may need to work outside of these standard hours from time to time and we will update residents before this occurs.

    When will construction start?

    Construction is planned to start in late 2022, weather permitting. We’ll determine further timing of construction activities as we progress and will consult with the community and nearby residents.

    When will the project be completed?

    At this stage, we expect the project to finish in 2024, weather permitting.

Dover Heights

    How did you choose the location of the new pump station?

    The Eastern Reserve pump station will receive flows from the Diamond Bay Ocean Outfalls. It will then direct the wastewater to the existing infrastructure on Old South Head Rd. We will continue to work with Waverley Council and the local community to minimise the visual impact of this design and will look for opportunities to further refine the pumping station’s footprint and engage a landscape architect to advise on the sensitive placement of aboveground infrastructure.

    What works are required at Diamond Bay Reserve?

    We’ll build a new pipeline from Diamond Bay Reserve to connect the system to the new pump station at Eastern Reserve. The pipeline will be laid using trenchless technologies but there will be some sections of open trench work. This will be located behind properties along Kimberley Street, nearby the existing boardwalk. Further site investigations will be required in this location to gain further insights on the geological environment.

Parsley Bay

    What changes have been made to the Parsley Bay Pump Station design?

    There are no changes to the overall appearance and location of the pump station. The design, however, now includes more information about the pipeline from Parsley Bay to Carlisle Street including the point where the water pipeline will connect to the existing water main. 

    To connect the Parsley Bay pump station to electricity and water, we will need to trench across Parsley Road and down Horler Avenue to install underground power lines and water pipelines. We will also need to remove power poles on Horler Avenue. 

    How did you choose the location of the new pump station?

    The two new wastewater pump stations will be located at Parsley Bay and Eastern Reserve.

    Parsley Bay is a critical location as all the wastewater collected in the Vaucluse catchment passes through Parsley Bay. 

     Currently, two key pipes funnel all the wastewater we collect from Vaucluse, Watsons Bay and Rose Bay North into the ocean via a third pipe, the Vaucluse Ocean Outfall Sewer. These three pipes intersect underground at Parsley Bay, and we need to redirect the water here to go to the Bondi treatment plant, which is why the pump station will be constructed here. The pump station will be located where the current toilet block is, next to the car park.


    What happens with the amenities block in Parsley Bay?

    We’ve been working closely with Woollahra Council and Sam Crawford Architects to develop the concept for the new amenities in Parsley Bay. We will be utilising the ground floor in the existing Caretaker’s Cottage, as it has the least impact to the reserve. 

     The new amenities will provide the same facilities compared to the existing amenities block. It will include separate male, female and accessible/family toilets and change facilities. The entrance to the female and accessible facilities will be next to the kiosk while the entrance to the male facilities will be on the side of the building along Horler Avenue.

     We are currently preparing the necessary documentation to lodge a Development Application with Woollahra Council for the new amenities. For more information about the amenities block and the design, please visit Newsletters | Refresh Vaucluse and Diamond Bay | Sydney Water Talk 

    Will the new amenities block at Parsley Bay be finished before construction starts?

    Sydney Water is still committed to ensure amenities remain accessible throughout our work in Parsley Bay. At this time, we expect it will be necessary to provide temporary amenities while work is carried out on the new pumping station and construction of the new amenities. We will continue to work closely with Woollahra Council and the community on the Parsley Bay works and will provide more detail to the local community as the work continues.

    Will there be a loss of car spaces at Parsley Bay carpark?

    Yes, during construction you will not be able to use the Parsley Bay carpark. We’ll continue to work closely with Woollahra Council to maintain as much of the available parking spaces as possible in the Parsley Bay carpark. As part of the design, we are looking at ways to maintain an accessible car space or provide a space for drop-offs.

    Will I be able to access the Parsley Bay swimming and recreational areas?

    During construction, we will maintain safe pedestrian access to Parsley Bay Reserve and the swimming area via access tracks. There may be times where we need to restrict access to the reserves due to public safety.

    We have not yet determined which access tracks we will use during construction and will consult with impacted residents on this during the detailed design phase if we identify restrictions to any existing access tracks. 

     We will provide residents with as much notice as possible on temporary changes to accessing reserves, tracks, swimming areas and amenities.

    Will removing power poles on Horler Avenue and installing powerlines affect my electricity?

    We’ll relocate two power poles on Horler Avenue to nearby locations and remove one light pole during construction and replace it with temporary lights. The work to install the underground powerlines at Parsley Road and Horler Avenue and remove power poles on Horler Avenue will take a few days. At this time, we will use generators to ensure power supply to residents and businesses is not disrupted.

Rose Bay

    Why has Mitchell Road, Spencer Street and Ian Street been added to this project?

    To meet the growing water services demands of the area to prevent overflows in wet weather events, we’ll increase the capacity of the wastewater system by upgrading the wastewater pipelines on Spencer Street and Mitchell Road to Old South Head Road. We’ll also be upgrading the existing emergency relief structure in Ian Street. 

    We’ve optimized the design by reducing the number of maintenance holes on Mitchell Road and made minor updates to the maintenance hole locations on Dover Road. 

Construction approach

    What construction techniques will you be using for the pipelines?

    Where we need to install water and wastewater pipelines across Parsley Road and along Horler Avenue, Carlisle Street, Dover Road, Spencer Street, Oceanview Avenue and Mitchell Road to Old South Head Road, we will use an open trench construction method. This is the most common installation method. As the name suggests, a trench is excavated to the required depth and alignment. The pipes are then welded together and placed on a level surface at the bottom of the trench. Once the pipe is laid, the trench is backfilled. 

    Trenchless construction will be done from Parsley Bay to Carlisle Street, Rose Bay, utilising Horizontal Directional Drilling (HDD). This involves the installation of pipes without the need to dig up open-cut trenches to lay the pipes. There is still a requirement to dig a launch and retrieval pit in the road to launch the drilling machine and eventually retrieve the pipe sections. Ground-borne vibration would be short term along the alignment. While trenchless construction is not suitable for all pipe installation it minimises the impact to environmentally sensitive issues. 

    We’ll continue to provide updates as we prepare for construction. 

    Will there be increased truck movements and road closures?

    Throughout the project, large trucks and machinery will need to travel down residential streets to deliver new and remove old equipment. We’ll have traffic control in place to guide vehicles and pedestrians around the work site.

     We’ll work closely with Councils to coordinate any roadwork and traffic management and reduce the duration of impact on the community. We’ll provide further details as we progress to construction. 

    Will there be noise and vibration impacts during construction?

    We’ll try our best to minimise construction impacts on residents, businesses and the community and will keep you updated during construction. 

    Before construction work starts, we’ll undertake dilapidation surveys and condition assessments of structures and properties that are within close proximity of any area requiring rock breaking and drilling. 

    Will Sydney Water replace any trees and vegetation that are removed during the project?

    Sydney Water is committed to providing the best outcomes for the environment and will have environmental measures in place to reduce impacts. The importance of trees and green spaces in our community, which provide shade and help cool our urban areas, cannot be underestimated. 

    During the detailed design phase and construction planning, we’ll investigate ways to reduce impacts to native vegetation communities, however, vegetation removal is required at Parsley Bay and Diamond Bay. This is mainly to facilitate access as well as to construct new wastewater infrastructure. The design will avoid clearing large mature trees and will not impact any threatened ecological communities. Where possible, all impacted vegetation will be reinstated at the completion of the proposal. If it is not possible to replace vegetation in the same location, we’ll consult with Waverley and Woollahra Councils and work with local bushcare groups on vegetation replanting.

    Will removing vegetation impact my privacy?

    Where possible, we will restrict vegetation removal to ground coverage. If we can’t do this or retain mature vegetation, we will consult any impacted landowners and seek to replace these with mature trees wherever possible.

    Will the new infrastructure cause odour issues?

    During detailed design, we will continue to design odour mitigation measures such as passive vent filters. Once the pumping stations have been built, we will test for odour using handheld equipment and sensors to ensure no nuisance odours are detectable which may impact surrounding residents. If we detect a nuisance odour, we will consider installing odour control equipment.