Tunnel excavation has already started for Stage 1 of WHT. Work underneath Emily Street in Rozelle began in June 2022, and tunnelling continues under Balmain from mid 2023 and towards the suburb of Birchgrove in 2024.

Excavation of the Stage 1 tunnels is expected to be complete in 2025.

Fit out and commissioning of the tunnel will be carried out as part of the Stage 2 work.

Stage 1 of the Western Harbour Tunnel is being excavated in two phases, primarily with a roadheader, an excavation machine that cuts rock in a circular motion suitable for creating the arched shape cavern required for road tunnels.

Six roadheaders in total will be used to excavate Stage 1.

The first phase involves excavation of the tunnel roof using a roadheader. The crew excavate between 1-5 metres at a time (depending on the design), before installing ground support into the tunnel walls, including rock bolts (metal rods) and shotcrete (sprayed concrete). We generally excavate around 20-25 metres of rock per week.

The second phase of tunnel excavation involves removal of the tunnel floor using a roadheader or rock hammer.

When using a roadheader, this work progresses much quicker than the first phase, at approximately 15-25 metres per day. On some occasions, we will need to use a rock hammer to excavate the floor. This work will be restricted based on vibration levels in compliance with project approvals.

Tunnel support activities include drilling, adding extra rock bolts, profiling, installing drainage and laying a new road pavement.

The tunnels are relatively deep. The tunnel starts at a depth of around 15 metres at Emily Street, Rozelle before going deeper to approximately 50 metres when it goes under Victoria Road. It keeps going deeper to a depth of 74 metres when it passes under Darling Street, Balmain, before starting to rise back to 50 metres when it reaches Cove Street, Birchgrove.

The project has approval to carry out tunnelling activities (including support activities) 24 hours per day, seven days a week. The first stage of tunnel excavation involves cutting of the roof using a roadheader. The crew cut forward between 1 and 5 metres at a time (depending on the design) before installing ground support which includes rock bolts (metal rods) and shotcrete (sprayed concrete). We generally progress this work at approximately 20-25 metres per week. The second stage involves the removal of the tunnel floor using a roadheader or rock hammer. When using a roadheader, the removal of the tunnel floor progresses at a much quicker rate of approximately 15-25 metres per day.

A letter will be dropped to all properties within a 50m radius of the tunnel alignment when we are approaching your area, about 2 - 6 weeks prior to when we expect to start tunnelling.

The project also sends an email to all subscribed residents every Friday with the latest tunnelling progress. This is the best way to keep track of the excavation under or near your property.

You can subscribe to these updates on the Contact Us page.

Tunnelling noise is dependent on the depth of the tunnel. The deeper the tunnel the less impact experienced by a property. You may hear some sound while we are tunnelling.

Roadheader excavation sounds like a refrigerator humming and can occur 24/7. Rock bolting creates a temporary drilling noise which will occur 24/7. As this drilling noise stops and starts, it can be more noticeable to residents.

The tunnels will be dug by a machine called a roadheader. A roadheader is an electrically powered excavation machine that has a rotating, rock-cutting head on the front, mounted to a boom. Roadheaders have been chosen because they are best suited to digging road tunnels as their arm can create the arched roof shape and a flat base, suitable for road construction to support the completed excavation, a rockbolting machine is used to install rockbolts into the tunnel roof. When the underground rock is cut using a roadheader, a loading device typically transfers the rock onto a conveyor belt which runs the spoil onto haulage trucks.

Rockbolts range in length depending on the ground conditions and excavation size. Rockbolts are drilled, tensioned and injected with grout to increase the strength of the tunnel roof Shotcrete is then applied to keep the tunnel roof and sides in place. The amount of shotcrete applied depends on the ground conditions and the excavation size Moxie’s are specialized dump trucks used to transport spoil inside the tunnels to the acoustic shed. The spoil is then loaded onto large trucks with trailers and taken off site to approved spoil tip sites. Receiver sites for spoil for the Western Harbour Tunnel Stage 1 are located mainly out west and include future developments.

What is the benefit of using road headers?

The roadheader tunnelling method has been the preferred construction technique for almost all major motorway tunnels in Sydney. This method will be used to tunnel the majority of the Western Harbour Tunnel, except for the section beneath the Sydney Harbour seabed, as planned.

Using roadheaders to tunnel north and south of the Harbour is the preferred method largely because of the suitable ground conditions and flexibility these machines provide in excavating different tunnel shapes.

The size of the tunnel will determine the length of time and number of times the roadheader will need to pass under a property. People may notice when the first phase of tunnelling excavation occurs, which is the excavation of the roof. This can take between 2-4 weeks.

The second phase may be noticeable for one week. If we’re excavating a wider section of tunnel, we could be in the area for up to three months.

The project has approval to carry out tunnelling activities 24 hours per day, seven days a week. This schedule is provided for two reasons, it:

·         significantly reduce the overall timeframe taken to excavate the tunnels and reduce the impact to residents

·         allows ground support to be immediately applied following excavation (safety requirement).

Tunnelling for Stage 1 will mostly take place between 6am Monday and 6pm Saturday (24 hours a day), giving residents a 2-night respite on weekends. As needed, tunnelling activities may take place inside the tunnels from 6pm Saturday to 6am Monday but we will notify before this occurs.

Ground material (spoil) will be loaded into trucks inside the tunnel, limiting noise impacts to nearby residents. Trucks will drive out of the WHT portal onto City West Link heading to tip sites primarily out west.

There is no spoil haulage planned on Victoria Road and through the Birchgrove peninsula. Spoil haulage and concrete deliveries are required to happen at night for ground support to be installed immediately after excavation.

Typically for complex major infrastructure projects, the design and construction approach presented in the Environmental Impact Statement (EIS) is at planning stage and is indicative only. The design presented in the EIS is subject to refinement once the Contractor delivering the project has been appointed and is able to carry out further investigations, engineering analysis and construction planning.

In February 2022, we carried out geotechnical and groundwater monitoring in the Rozelle, Balmain and Birchgrove area. Information gathered during this stage was used to help finalise the detailed design of the tunnel alignment and location of supporting structures for the project.

The final tunnel alignment shifted from what was presented in the EIS, following this detailed design process, in some locations, by up to 70 metres. This was to take advantage of better ground conditions for tunnelling and to provide a straighter route, making it easier and safer to drive. While the location and depth of some of these tunnels has changed, the overarching impacts assessed under the EIS, are expected to be the same. The location of the final detailed design compared to the EIS reference design is captured in this map.

No additional temporary construction sites are required. Now that a TBM delivery methodology is being proposed to tunnel under Sydney Harbour there are significant benefits for the people of NSW. In fact, the adoption of the TBM methodology for tunnelling under Sydney Harbour will mean that we have reduced the total number of temporary construction sites needed by four. The two sites on Sydney Harbour, and the sites at Berrys Bay, Waverton, and Yurulbin Point, Birchgrove, will no longer be required for construction.

Change in methodology means we no longer require a temporary construction site at or cofferdam at Yurulbin Point. As a result, there will be no above ground Western Harbour Tunnel tunnelling site at this location impacting local residents, meaning we can avoid the temporary impacts of an above-ground tunnelling site, such as noise, dust, vehicle haulage, visual amenity and loss of open space.

 There will be no impact to Birchgrove Wharf, and its ferry operations.

Transport and its contractor, Acciona Construction Australia, will be carrying out further planning and detailed design work on the project which will consider further opportunities to deliver improved community outcomes. This will also refine the tunnel alignment and depth as part of detailed design.

A Place Design and Landscape Plan (PDLP) is an important stage of a project illustrating, in more detail than the Environmental Impact Statement (EIS), what a project will look like, how it contributes to places, what the buildings, bridges, and tunnels look like, what the landscape is like, where the paths and cycleways are, and how it all comes together with the road infrastructure. It is the opportunity for the community to have a final look at the design before it is built. 

During the tender process for Stage 2 of the project, different designs and methodology were considered to ensure the best design and outcomes are considered for the project, community and environment. Acciona submitted an alternative methodology of using a Tunnel Boring Machine (TBM) to tunnel beneath the Sydney Harbour seabed. This design was assessed and selected as it provides the best overall value for the people of NSW and minimises impacts on the local community and environment.

The specialised TBMs will each tunnel for about 1.5km from Birchgrove to Waverton including under the Sydney Harbour seabed, connecting the northern and southern ends of the project. Using TBM methodology means we no longer require temporary construction sites at Yurulbin Point or Berrys Bay, and cofferdams are no longer required at Yurulbin Point or Balls Head. This also means that no dredging will be required and there will be no impacts to Birchgrove Wharf.

Transport has determined the TBM methodology to be the best overall solution to deliver Stage 2 tunnelling beneath Sydney Harbour.

A design using a TBM was originally considered as part of the EIS. At the time, an Immersed Tube Tunnel approach was assessed as being the most suitable option due to the nature of the project as well as the local ground conditions beneath Sydney’s Harbour.

Since the development of the concept design in 2017 and the proposed reference design in 2018 for the project, technology and the market have evolved. Other projects have recently proven the efficiency and success of using a TBM to tunnel beneath Sydney’s Harbour.

As this methodology was not fully assessed and approved during the EIS, the project sought approval to use the TBM methodology through a modification, which the community was consulted on in 2023. This is a standard process when making changes to an approved major project.

The Department for Planning, Housing and Infrastructure (DPHI) approved the Modification to the Western Harbour Tunnel project in January 2024.

Since the development of the concept design in 2017 and the proposed reference design in 2018 for the project, technology and the market have evolved. Sydney Metro has recently proven the efficiency and success of using a TBM to tunnel in varying ground conditions beneath Sydney’s Harbour.

A tunnel boring machine, often referred to as a TBM, is a machine used to excavate tunnels.

At the front of the TBM is a cutter head which excavates the ground. As the tunnel advances, precast concrete segments are installed to support and permanently line the tunnel.

The excavated material is mixed with slurry and transported to a Slurry Treatment Plant. The excavated material is separated from the slurry and prepared for recycling or disposal.

TBMs are used worldwide and in NSW as a tunnelling solution. Using a TBM significantly reduces our surface impacts. By launching the TBM completely underground, it removes the need for construction sites and cofferdams at Birchgrove and Waverton. It also removes the need for dredging in Sydney Harbour.

TBM will be used for a 1.5km section of the tunnel beneath Sydney Harbour and will lead to improved environmental and community outcomes including:

•       reduced number of temporary construction sites (Berrys Bay, Yurulbin Point, Sydney Harbour sites no longer required)

•       with no tunnelling works from Berrys Bay, the Berrys Bay master plan will be delivered earlier

•       no dredging of Sydney Harbour

•       no removal of Sydney Harbour sediment near Balls Head

•       no impact to existing harbour operations (HMAS Waterhen, VIVA Energy, ferries, recreational watercraft)

•       Birchgrove Ferry Wharf no longer impacted

•       no cofferdams at Yurulbin Point or Balls Head

•       no temporary relocation of MV Cape Don

•       temporary relocation of moorings at Berrys Bay no longer required

•       upgrade and utilisation of moorings at Snails Bay no longer required

The TBMs will be assembled in an underground launch cavern that will be excavated in Birchgrove. No additional dive or launch sites are required for the TBMs.

Each piece of the machine will be transported on a truck to the Western Harbour Tunnel entry, which is already excavated as part of the Rozelle Interchange and driven to the underground launch cavern.

This is an area underground, where the TBMs are assembled to start tunnelling under Birchgrove towards Waverton. This will likely be located underground in Birchgrove, near the harbour. The final depth of the excavation tunnel will be known through detailed design.

The majority of the launch cavern used to assemble and launch the TBMs, does not get filled in and instead becomes part of the operational and permanent road tunnel.

Consistent with complex major infrastructure projects progressing through an environmental planning and assessment process, the design and construction approach presented in the Environmental Impact Statement (EIS) was at planning stage and indicative only. Further refinement as part of detailed design is now underway and we are working to develop the design and construction methodologies. This includes tunnel alignment, depth and supporting infrastructure.

As the TBM methodology was not fully assessed and approved during the EIS, the project sought further approval from the NSW Minister for Planning through a modification. We consulted communities across the lower north shore, inner west and Emu Plains about the Modification in July and August 2023, and we will continue to engage with these communities as we work to deliver the Western Harbour Tunnel.

The Department for Planning, Housing and Infrastructure (DPHI) approved the Modification to the Western Harbour Tunnel project in January 2024.

About the Modification
The Modification Report was submitted in July 2023, proposing to amend the Western Harbour Tunnel project granted planning approval in January 2021.

The approved Modification means that we are changing the construction methodology for tunnelling under the Sydney Harbour between Birchgrove and Waverton from an Immersed Tube Tunnel to using Tunnel Boring Machines (TBMs).  This change will reduce construction impacts on the community and environment by:

• not dredging in Sydney Harbour

• reducing the overall number of construction support sites by removing the need for construction support sites at Yurulbin Point, Berrys Bay, White Bay North and Victoria Road

• removing the need for cofferdams in Sydney Harbour at Birchgrove and Balls Head

• removing impacts to Birchgrove Ferry Wharf and ferry services

• reducing impacts to ferries and boats on Sydney Harbour.

Approval of the Modification also means there will be a new construction support site at Emu Plains and changes to our existing support sites at the City West Link Portal, Glebe Island and Ridge Street, North Sydney.

All other construction activities and elements of the approved project not included in the Modification Report will continue to proceed as planned.

As with any major infrastructure project of this scale, the approved changes are subject to the Minister’s Conditions of Approval. You can learn more about these  conditions and view the full Modification Report here on the Department of Planning and Environment’s Major Projects portal.

Click here to view the project’s original Environmental Impact Statement and Minister’s Conditions of Approval.

A Tunnel Boring Machine (TBM) has the capacity to tunnel through the rock bed and marine clay, beneath the harbour as opposed to dredging. This removes the need to manage harbour sediment and subsequent disposal to landfill or offshore.

Transport has determined the TBM methodology to be the best overall solution to deliver Stage 2 tunnelling beneath Sydney Harbour. Transport remains committed to minimising impacts to the community and the environment.

Dredging is a relatively common activity within New South Wales ports and coastal waters, with specialised contractors and equipment designed to meet project and environmental requirements in a variety of conditions. What we were planning is similar to previous work already carried out on many projects within Sydney Harbour, including at Garden Island in 2019.

ACCIONA submitted an alternative methodology of using a Tunnel Boring Machine (TBM) to tunnel beneath the Sydney Harbour seabed. This design was assessed and selected, as part of their overall solution, which provides the best value for the people of NSW, and further minimises impacts on the local community and environment.

Following a rigorous assessment of the local ground conditions, a slurry TBM has been selected as the most appropriate type of TBM for the Western Harbour Tunnel.

Excess material or material that cannot be reused on the project will be taken to an approved location that can receive the material. Some material may be suitable for use on other projects.

It is currently proposed that the Slurry Treatment Plant will be located in the underground ventilation cavern. This section of the tunnel will be excavated as part of Stage 1 in Rozelle.

There will be two TBMs used to tunnel the southbound and northbound road tunnels. They will not bore alongside each other simultaneously. It is standard practice that the TBMs are spaced out meaning one will start first and bore at a distance ahead of the other.

The TBMs used for the Western Harbour Tunnel are some of the biggest in the world. The TBMs are expected to each be about 16.4m in diameter, however, the final width may be reduced through the detailed design process. The TBMs are about 120m in length.

Our specialised TBM machines will each tunnel for about 1.5km from Birchgrove to Waverton including under the Sydney Harbour seabed, connecting the northern and southern ends of the project.

Our specialised TBM machines will tunnel for about 1.5km under from Birchgrove to Waverton including under the Sydney Harbour seabed, connecting the northern and southern ends of the project. The TBM methodology has been adopted as an alternative to using the originally planned Immersed Tube Tunnel construction method. With the expected geology under Sydney Harbour, the TBM method is efficient and has a reduced impact on the environment and community.

The majority of the Western Harbour Tunnel will be excavated using electrically powered machines known as roadheaders, as planned. Roadheaders were found to be less suited to tunnelling beneath the harbour, as opposed to under land.

The contractor is still undertaking the procurement process to source the machines. More information about where the TBMs will come from will be known once the contractor has completed this process.

Transport and the awarded contractor for Stage 2, ACCIONA are committed to creating opportunity for local businesses and suppliers on this major project. In collaboration with industry, the delivery of Western Harbour Tunnel will include the development and implementation of a business capability program to increase the capability and capacity of ANZ Small and Medium Enterprises and social enterprises.

Transport for NSW is confident our work can be completed without posing significant risk to the marine environment or users of the harbour.

The Western Harbour Tunnel and Warringah Freeway Upgrade Environmental Impact Statement (EIS) is based on expert peer-reviewed advice, past experience and world’s best practice.

We understand Dawn Fraser Baths is an important swimming location for the community.

The Baths will remain open throughout construction, and there will be no direct impacts on the Dawn Fraser Baths while we build the Western Harbour Tunnel.

TBM machines can only move in one direction. Once we have completed tunnelling the TBM section of the project, the TBMs will be driven into a ‘receiving chamber’. We will salvage as much of the machine as possible, removing it in pieces back through the entrance to the tunnel at Rozelle.

The cutterhead and shield of the TBMs cannot be safely salvaged and will be buried underground and encapsulated in the receiving chamber. This is a normal process when tunnelling using the TBM methodology, and all safety and environmental measures will be carried out to ensure it is safely buried. Burying the cutterhead and shield of the TBMs mean we do not need to create an above-ground construction site to remove them, which would have significant impacts on the local community.

Consistent with complex major infrastructure projects progressing through an environmental planning and assessment process, the design and construction approach presented in the Environmental Impact Statement (EIS) was at planning stage and indicative only.

Further refinement as part of detailed design is now underway and we are working to develop the design and construction methodologies. The detailed design phase will take approximately 12 to 18 months to complete and will be progressively incorporated into the planning and delivery of construction work.

As the TBM methodology was not fully assessed and approved during the EIS, we sought further approval from the NSW Minister for Planning to modify the Conditions of Approval (CoA), in accordance with the requirements of Division 5.2 of the Environmental Planning and Assessment Act 1979.

From 19 July to 15 August 2023, we invited the community to have their say on proposed changes to the way we build the Western Harbour Tunnel under Sydney Harbour.

We displayed the Modification Report which outlined a modification to the approved Western Harbour Tunnel project to change the construction methodology for crossing under Sydney Harbour between Birchgrove and Waverton from the approved Immersed Tube Tunnel (IMT) method to Tunnel Boring Machines (TBMs).

The Department for Planning, Housing and Infrastructure (DPHI) approved the Modification to the Western Harbour Tunnel project in January 2024.

About the Modification
The Modification Report was submitted in July 2023, proposing to amend the Western Harbour Tunnel project granted planning approval in January 2021.

The approved Modification means that we are changing the construction methodology for tunnelling under the Sydney Harbour between Birchgrove and Waverton from an Immersed Tube Tunnel to using Tunnel Boring Machines (TBMs).  This change will reduce construction impacts on the community and environment by:

• not dredging in Sydney Harbour

• reducing the overall number of construction support sites by removing the need for construction support sites at Yurulbin Point, Berrys Bay, White Bay North and Victoria Road

• removing the need for cofferdams in Sydney Harbour at Birchgrove and Balls Head

• removing impacts to Birchgrove Ferry Wharf and ferry services

• reducing impacts to ferries and boats on Sydney Harbour.

Approval of the Modification also means there will be a new construction support site at Emu Plains and changes to our existing support sites at the City West Link Portal, Glebe Island and Ridge Street, North Sydney.

All other construction activities and elements of the approved project not included in the Modification Report will continue to proceed as planned.

As with any major infrastructure project of this scale, the approved changes are subject to the Minister’s Conditions of Approval. You can learn more about these  conditions and view the full Modification Report here on the Department for Planning, Housing and Infrastructure (DPHI)’s Major Projects portal.

Click here to view the project’s original Environmental Impact Statement and Minister’s Conditions of Approval.

There will be future opportunities to provide input to the Western Harbour Tunnel project. We will work with councils, communities and stakeholders to ensure the best possible use of this space once we have finished our work and will be seeking your valuable input to help design these legacy projects.

There will be a Place, Design and Landscape Plan (PDLP) carried out as part of main work activities. As per E178 in the Conditions of Approval (CoA), the PDLP must be prepared by a suitably qualified and experienced team, in consultation with relevant councils, the community and affected landowners and businesses.

The proposed change in methodology means we no longer require a construction site at Berrys Bay. As a result, there will be no Western Harbour Tunnel construction work activities at this location, meaning we can avoid the temporary impacts of an above-ground tunnelling site, such as noise, dust, vehicle haulage, visual amenity and loss of open space. There will be no impact to harbour operations or the Coal Loader Sustainability Centre and no temporary relocation required for the MV Cape Don.

Our objective is to ensure there are no buildings at risk of damage from vibration and settlement impacts while we are carrying out our work.

The new TBM method does not pose additional risk to properties from vibration.

As is the standard process for tunnelling, we will offer eligible properties in close proximity to the tunnel alignment and any settlement or vibration-intensive works a free property condition survey. While we are building, we will monitor noise and vibration to make sure it meets the appropriate guidelines.

Despite no longer needing to use Berrys Bay temporarily for Western Harbour Tunnel construction, the NSW Government is committed to returning the space to the community as foreshore parklands and public spaces. Without the construction site at Berrys Bay, work to revitalise Berrys Bay in Waverton can start much sooner than initially expected.

Following community consultation in 2022, Transport released the final master plan for Berrys Bay in February 2023.

Early work for Stage 2 commenced on 22 May 2023 and includes further geotechnical investigations, archaeological investigations and more. For more information, view the notifications for work both north and south of the Harbour here.

The project reached a major milestone with the start of roadheader tunnel excavation on the north side of the Harbour from late November 2023 at Cammeray. Read our Start of Tunnelling notification for more information. To learn more about our construction activities and how we manage any potential impacts from our tunnelling activities, please refer to our Stage 2 fact sheets.

We will contact residents before any work starts in their area. Community information sessions will be scheduled before tunnelling starts in each suburb along the alignment.

We understand there is concern about the potential for vibration and settlement impacts from tunnelling works. Ground movement does not necessarily result in property damage, in fact it is highly unlikely. Buildings experience ground movement naturally through environmental changes such as seasonal climate variations, vegetation (tree roots), structural effects (different building types of age of construction) or ground effects (reactivity to soil).

Properties above the final tunnel alignment (and within 50 metres of the alignment, in line with planning approvals) will be offered a Property Condition Survey. Even though it is highly unlikely for any damage to occur from our tunnelling, Transport encourages anyone who is eligible for a Property Condition Survey to take up this offer following confirmation of the final alignment.

If your property is located within 50 metres of the tunnels you will be offered a property condition survey (PCS) before and after construction. The survey is free and will ensure there is a clear record of your property’s condition. In the unlikely event damage is caused by our construction work, it will be repaired at no cost to you.

Construction of these tunnels will continue to follow well-established methods used on other major tunnelling projects in the Sydney region. They will be built safely, and in line with the project’s planning approvals.

For Stage 1 all properties within 50 metres of the tunnel are eligible for a PCS both before and after construction of the tunnels. The project strongly recommends property owners accept the offer to have one completed. The PCS is free to residents, and will provide a photographic baseline for comparison if you have concerns about property damage that you believe was caused by construction activity. In the unlikely event that any damage is caused by our construction work, rest assured it will be repaired at no cost to you.

You may have already undergone a PCS or received several offers from other projects in the area, we strongly urge you to accept this offer for each individual project. Accepting these offers ensures that your property is documented in the construction phase for each project.

Stage 2 is currently undergoing detailed design, once this is finalised, and the final alignment of the tunnel known, eligible residents will be contacted with offers for a PCS.

Property Condition Surveys involve a visual inspection of the interior and exterior of a property to document its condition before construction work takes place nearby, in accordance with the Australian Standard 4349.1 Inspection of Buildings.

Property Condition Surveys are completed at no cost to you, and at a date and time that is convenient to you. The property owner (or nominee) will need to be present to grant access to the property.

Inspections typically take around two to three hours to assess and photograph the internal and external condition of the building/s, depending on the size and features of your property. The outcomes of the inspection will be detailed in a property condition report, and you will be supplied with a copy. Transport and ACCIONA will also keep a copy.

The report will also include photographs to provide an accurate record of the current condition of the property and will record any noticeable defects. Inspections are scheduled to take place during daylight hours to accurately record the condition of the property’s exterior.

Property Condition Surveys (PCS) will be offered to properties close to the construction area for the Western Harbour Tunnel as a precautionary measure and offer peace of mind to property owners during construction.

If your property is located within 50 metres of the outer edge of the tunnels you will be offered a PCS before construction starts near your property. The survey is free of charge and will ensure there is a clear record of your property’s condition.

We will make three attempts via letter to offer a PCS. If you’ve subscribed to our email distribution list the project will attempt to also contact you via email.

We recognise there are multiple projects working in the Inner West and North Sydney areas and you may have organized a property condition survey for another project previously. We strongly encourage you to accept a Property Condition Survey offer for each individual project you are offered. Accepting these offers ensures that your property is documented in the construction phase for each project.

Western Harbour Tunnel Stage is a separate project from others in the area and is being carried out by a different construction contractor.

It is important that a new property condition survey is completed just prior to Western Harbour Tunnel construction commencing in your area so that in the unlikely event of any damage to your property we can determine the timeframe this occurred.

You should contact the project team as soon as possible to begin the process of filing a property damage claim. You do not have to wait until the post-construction Property Condition Survey (PCS) is complete to file a claim for property damage.

The property damage team will then contact you and walk you through the property damage process.

If you’re not satisfied with the project's decision on your damage claim, you can request your claim be reviewed by an Independent Property Impact Assessment Panel (IPIAP) through Transport for NSW. The panel is made up of independent geotechnical and engineering specialists who have been approved by the Department of Planning and Environment (DPE).

Transport and ACCIONA will carry out further planning and detailed design work over the coming 12 months, and this includes progressively refining the required tunnel depth and alignment. The latest tunnel alignment is available to view here: Environmental Impact Statement map.

Transport will be contacting those properties closest to the tunnel alignment once this is confirmed through the detailed design process through letterbox notifications and doorknocking.

The Western Harbour Tunnel Stage 1 is mostly being constructed through Hawkesbury sandstone. This is a robust and consistent rock structure that is ideal for tunnelling due to its uniform strength.

This is the same ground conditions that the Rozelle Interchange JHCPB team had when excavating under Leichhardt, Rozelle and Lilyfield.

Settlement is the movement of the ground, generally caused by changes in stresses within the earth. Excavation of tunnels will almost always cause some settlement. Tunnel-induced settlement is the result of the ground relaxing around newly excavated area and occurs at the time of excavation and the weeks proceeding. Groundwater drawdown is when groundwater flows into the tunnel causing ground at the surface to lose volume. This form of settlement typically occurs very slowly over the lifetime of the project. Ground movement does not necessarily result in property damage. Buildings generally experience ground movement naturally through environmental changes such as seasonal climate variations, vegetation (tree roots), structural effects (different building types of age of construction) or ground effects (reactivity to soil).

The Department of Planning and Environment (DPE) has provided acceptable limits for settlement. These limits permit maximum of 30mm ground movement for two story buildings and less, 20mm ground movement for three story buildings and more. There are also settlement limits provided for parks and roads.

During the design development phase, a geotechnical model is created to understand the ground and hydrogeological conditions along the tunnel alignment. The report informs the design to ensure that settlement levels remain within these thresholds. In most instance the tunnels are designed to have settlement limits much lower than the acceptable limits.

During excavation, the team uses a conservative trigger (green, amber, red) system to address changing ground movement levels. Geotechnical engineers map the tunnel rockface at every excavation advance to measure any settlement and this information is incorporated into a daily planning meeting with construction teams.

Monitoring occurs on the surface and inside the tunnel throughout excavation, as shown in the image below. Residents may notice prism markers being installed on roads and footpaths by our survey team ahead of tunnelling in an area.

These prisms are used to monitor potential ground movement throughout excavation. We will monitor these prisms on a daily basis at the location of our tunnelling activities.

Generally, noise and vibration impact from tunnelling is most noticeable when we are closest to a property, increasing on approach and reducing as we move away. The deeper the tunnel the less likely you are to hear excavation (generally from below 30 metres is low noise impact), so 60-70 metres will be barely audible. The sounds you may hear during tunnelling include:

·    First phase:roadheader excavation sounds like an old refrigerator humming which will occur 24/7 and rock bolting which creates a temporary drilling noise. As this drilling noise stops and starts, it can be more noticeable to residents.

·     Second phase: daytime rock hammering will create a repetitive tapping sound varying in impact depending on your property's location to the work. Tunnel support activities: including rock bolting and drilling create a temporary drilling noise. As this drilling noise stops and starts, it can be more noticeable to residents.

Ground-borne noise (GBN) is the conversion of ground-borne vibration (GBV) which passes through the ground and into a built structure, resulting in audible noise levels. When assessing GBN, there is a correlation between ground borne noise and ground borne vibration.

We measure noise in decibels. Noise is measured, predicted, and assessed in accordance with the relevant legislative guidelines. Our noise modelling considers the local ground conditions and construction methodologies.

If we predict you may experience noise levels over the guidelines, we will implement additional mitigation measures and monitor noise levels. Our assessments are conservative and always assess the worst-case scenario. We often find when we are working the noise generated is less than we predicted. For information about noise see our managing noise page on our portal.

While we are building, we will monitor noise and vibration to make sure it meets the appropriate guidelines. Throughout construction we regularly monitor noise at different times of the day and night to ensure noise is within our predicted noise levels. This monitoring lets us know if we need to change our construction methods, adjust our mitigation measures, or adjust the noise model.

All our work will be carried out in line with the project’ Conditions of Approval, Environment Protection Licence and Construction Environmental Management Plan which are overseen by the Department of Planning and Environment (DPE) and NSW Environment Protection Authority (EPA).

In line with project approvals, respite is provided if a property is predicted to have noise levels exceeding 45 decibels for more than two consecutive nights.

Due to the tunnels being so deep, there are currently no properties along the WHT Stage 1 alignment that are expected to reach noise levels of 45 decibels.

If noise modelling indicates your property meets these criteria, the project will proactively contact you to discuss the available options ahead of the work starting.

The Environmental Protection Authority (EPA) and Transport for NSW have informed, consulted, and have approved these limits and respite thresholds. Therefore, the project strictly adheres to the above criteria to avoid inequity amongst properties along the tunnel alignment.

If your property is above an underground tunnel, you will not hear any operational noise from vehicles using the tunnel. For more information about how we manage operational noise can be found at the bottom of the page of our managing noise page.

The Rozelle Interchange project scope included the construction of one WHT ventilation outlet for the project. This ventilation outlet is one of three-cylinder structures on the Rozelle Rail Yard site (sitting above City West Link) that serve as part of a ventilation facility for the WHT, M4 and M5 tunnel portals at the Rozelle Interchange.

The second ventilation outlet for WHT will be located in the Warrigah Freeway corridor to the north of Ernest Street in Cammeray and is yet to be built.

Tunnel ventilation systems generally work most efficiently and effectively when the ventilation outlet is positioned near the exit ramp. This is why the ventilation outlets for modern tunnels are located near to tunnel exit ramps.

The ventilation outlet for the Western Harbour Tunnel will not be filtered.

The Western Harbour Tunnel ventilation system will be built to meet strict air quality standards using state-of-the-art ventilation and tunnel design.

In NSW we have an Advisory Committee on Tunnel Air Quality, chaired by the NSW Chief Scientist and Engineer, which consists of a range of experts in fields related to road tunnels, air quality and human health. This includes the NSW Chief Health Officer and an independent, international air quality expert.

The Committee has released a report in relation to road tunnel air quality which found emissions from well-designed road tunnels cause a negligible change to surrounding air quality, and as such, there is no discernible health benefit for surrounding communities in installing filtration and air treatment systems in such tunnels.

Filtration does not remove all pollutants from tunnel exhaust, therefore Transport for NSW will still need to operate a ventilation system, complete with inlets and outlets to protect the local air quality and tunnel users. The ventilation systems we use in NSW in our road tunnels are built to meet strict air quality standards and use state-of-the-art ventilation and tunnel design.

Sydney’s motorway tunnel ventilation outlets, including those for Western Harbour Tunnel, are designed to propel tunnel air high into the atmosphere. Once in the atmosphere, the ejected tunnel air is diluted hundreds of times, resulting in little, if any, change to the quality of the air people breathe.

You can learn more about ventilation systems, filtration and air treatment systems by visiting chiefscientist.nsw.gov.au or nswroads.work/airquality.

Our commitment is that the tunnels will be built to meet strict air quality standards using state-of-the-art ventilation and tunnel design.

Our assessments have shown emissions from the ventilation outlets for the project will have a negligible contribution to surrounding air quality and will be generally undetectable. The ventilation outlets will be continuously monitored, and the EPA will regulate the ventilation outlets to ensure they meet air quality limits.

You may be interested to know that you will experience an improvement in air quality along the Western Distributor, Sydney Harbour Bridge and Warringah Freeway as the result of more vehicles using the Western Harbour Tunnel, reducing traffic on surface roads.

Independent reviews of 2 years of post-operational air quality monitoring data have been conducted for NorthConnex, WestConnex M8 and the M4 tunnels. These reviews found that emissions from the NorthConnex, WestConnex M8 and the M4 ventilation outlets have no detectable impact on local air quality.

The reviews for NorthConnex and the M4 tunnels found significant improvements in local air quality due to projects removing traffic from surface roads. Communities along these corridors stand to benefit from the removal of thousands of vehicles from local surface roads.

Air quality assessments were undertaken as part of the Environmental Impact Statement (EIS) for the Western Harbour Tunnel is available on our interactive portal.

The EIS has been prepared by a team of qualified professionals, including technical specialists, and was reviewed by subject matter experts from Transport for NSW to provide a balanced, merit-based EIS in accordance with the Environmental Planning and Assessment Act 1979, the Secretary’s environmental assessment requirements and applicable NSW assessment policies.

As part of the preparation of the air quality impact assessment for the project, Appendix H (Technical working paper: Air quality) was issued to the Office of the Chief Scientist and Engineer and the Advisory Committee on Tunnel Air Quality (ACTAQ) to carry out a scientific review of the environmental impact assessments relating to ventilation outlets. To maintain independence and robustness of the review process, two independent reviewers were engaged by the Office of the NSW Chief Scientist and Engineer.

The Western Harbour Tunnel and associated ventilation systems would be built and operated in compliance with conditions of approval set by the Department for Planning, Housing and Infrastructure (DPHI). Further, the monitoring of ventilation outlet emissions during operation would be regulated under an Environment Protection Licence issued under the Protection of the Environment Operations Act 1997 (NSW).

Air quality would be continuously monitored within the ventilation outlets and tunnel 24 hours a day during operation and real-time data would be used to ensure compliance with strict air quality criteria. Air quality data would be made publicly available as close to real time as possible on a dedicated webpage.

Ambient air quality monitoring would be carried out for 12 months before, and a set period of time, likely at least 24 months, after the tunnel opened to verify everything was performing as expected and confirm compliance with air quality goals.

The location of these monitoring stations and duration of monitoring will be informed by the Air Quality Community Consultative Committee (AQCCC), which will comprise of representatives from the tunnel operator, local council and local community. The location of the monitoring stations will be verified by the Air Quality Independent Reviewer (AQIR), with consideration of advice form the EPA. Air quality information will also be available on the tunnel operator’s website.

The AQCCC will be independently chaired by a chairperson appointed in consultation with the DPE.

We have a number of resources available on our Western Harbour Tunnel portal, including the Air quality fact sheet, Interactive map, Guide to the EIS, and Chapter 12 of the Environmental Impact Statement: Air quality. The Department of Planning and Environment has also published the Independent Peer Review – Air quality on the Western Harbour Tunnel planning portal.

In addition to the above resources, you may be interested to know that Transport for NSW has a dedicated Air quality portal for all your questions on being located near ventilation outlets, how the ventilation outlets work, road tunnels, vehicle emissions and more. On this portal you can find a video series from the experts addressing air quality concerns, FAQs, and additional resources. Visit the dedicated Air quality portal at nswroads.work/airquality

Transport for NSW manages all property acquisitions for the project and will need to compulsorily acquire ‘subsurface’ land to create a path for the tunnel. This includes some land passing directly under properties. The surface area and any dwellings or other structures on your land will not be affected by subsurface acquisition.

Read our Property acquisition of subsurface land fact sheet for more information.

We will contact relevant property owners well before construction in their area starts to provide key information about subsurface acquisition. This will include a link to our online tunnel tool so you can see where the tunnels pass in relation to your property, how deep and how far away they are, and how to contact the team if you have any questions.

Following our initial letter, an official Property Acquisition Notice (PAN) is sent out.

The subsurface acquisition process will move progressively along the tunnel alignment in groups. Transport for NSW will contact you if the project needs to acquire any land under your property as this information becomes available.

All properties impacted by subsurface acquisition for Stage 1 have been contacted.

Yes. In the majority of cases, underground land acquisition will not affect the future use of your property. We will write to you advising of the proposed acquisition and will include a sketch which indicates the land or easement below the surface which needs to be acquired.

As the land is being acquired unilaterally by Transport for NSW, with the assistance of NSW Land Registry Services, there is no requirement for any landowner or mortgagee to provide any documentation.

The Land Acquisition (Just Terms Compensation) Act 1991 (NSW) explains that property owners are not eligible for compensation for subsurface land unless specific circumstances apply.

The health and safety of our workers, the community and the environment is our priority. A comprehensive health impact assessment was carried out as part of the Environmental Impact Statement (EIS) for the Western Harbour Tunnel and Warringah Freeway Upgrade project. This assessment can be found in Appendix I – Health assessment. A health impact assessment is a way of determining what the consequences to health (both positive and negative) of the project may be.

The human health assessment for the project has focused on health-related impacts associated with key air quality, noise and vibration and social aspects. The report includes a detailed review of what impacts may occur, who may be exposed to these impacts and mitigation measures. An overview of the findings can be found in EIS Chapter 13 – Human Health.

We acknowledge some areas experience an overlap with impacts from more than one project or experience projects that are in construction consecutively over extended periods of time. Cumulative impacts have been assessed in EIS Chapter 27 – Cumulative Impacts.

Construction fatigue is recognised as an important issue for communities in the vicinity of large construction projects that overlap in time or space. We will work with other projects in the area to mitigate impacts where possible and further opportunities to manage construction fatigue will be considered during the detailed design and construction of the project.

The Planning Minister reviewed the Human Health and Cumulative Impact assessments and approved the Western Harbour Tunnel being aware of this cumulative impact. The assessments were prepared to meet the Secretary’s environmental assessment requirements and in accordance with national and international guidance endorsed or accepted by Australian health and environmental authorities.

We have been collaborating with relevant teams on nearby projects to align our work and minimise impact on you. We continue to work closely throughout the planning and delivery of our projects to achieve this outcome.

Transport for NSW acknowledge a project of this scale will change the local community during construction and operation. We are committed to being the best neighbour we can and ensuring the safety of the community and our workers. The community will continue to be kept updated throughout all phases of the project.

We will use a variety of consultation tools and activities to inform and engage the community, stakeholders and our customers about our work as it progresses, including weekly portal updates, Community Updates, Fact Sheets, email updates, letterbox and online notifications and more. Following positive feedback, we will continue to offer online information sessions as a regular way of engaging with the community.

Depending on health advice, we may not always be able to door knock residents who live close to our work sites, we may carry out any face-to-face engagement as appropriate. For more information about how we work with the local community, please refer to the Community Communications Strategy (CCS).

We are continuing to build our knowledge of your community and surrounding local businesses to help us identify further ways to minimise impacts during construction. We would like to invite you to participate in a short survey so we have a greater understanding of you and your circumstances. To complete the survey, please visit: nswroads.work/whtcommunitysurvey

We will continue to work with key stakeholders and the local community to identify issues and opportunities to reduce the impact of our work wherever possible.

Please complete this form if you would like to subscribe to suburb specific updates and stay up to date with the latest information on the Western Harbour Tunnel project.

Projects in your area

We recognise there are other major infrastructure projects in this area and are working closely with other projects in the area. We are working closely with the Rozelle Interchange and Sydney Metro project teams to manage the cumulative impact as much as possible.

Getting in touch

If you have any questions or would like more information, please contact the Western Harbour Tunnel project team:

Phone: 1800 931 189

Email: whtbl@transport.nsw.gov.au