Nowra Bridge project - Princes Highway upgrade

Reviewed

Project overview

The Nowra Bridge project will provide a new four lane bridge over the Shoalhaven River, upgraded intersections and additional lanes on the Princes Highway.

The $342 million project is jointly funded by the NSW and Australian Governments. Major work started in mid-2020 and the project is expected to be complete by mid-2024.

Latest news

November 2023 – Major work comes to an end

Work to place the final layer of asphalt and permanent line marking is now complete which marks the end of major work on the Nowra Bridge project. Minor work will continue across the project in 2024 as we complete landscaping, small pavement and footpath work, and restore the project compounds and ancillary sites.

Project information

Background

The heritage listed Nowra Bridge crosses the Shoalhaven River and is an unofficial gateway to the South Coast. The historic bridge opened in 1881 and is a rare example of a pin-jointed Whipple truss bridge.

The Nowra Bridge project provides a new four lane bridge over the Shoalhaven River, and upgrades to over 1.7Km of the Princes Highway, including improved intersections and additional lanes.

The $342 million project improves traffic flow and eases congestion on a major section of the Princes Highway and delivers safer, more reliable journeys within the Nowra-Bomaderry area.

The project's need is based on the replacement of the existing historic southbound bridge which is in poor condition, has substantial maintenance costs, restrictions on overheight and overmass vehicles and has reached the end of its serviceable life. 

In February 2023, the new Nowra Bridge opened to traffic and the historic bridge was retired from road traffic. View the Historic Nowra Bridge repurposing page to find out more about the future of the historic bridge.

Detailed design

In 2017, the community was asked for feedback on the concept design for the Nowra Bridge project. This feedback was complied into a submissions report and was released in 2018.

Following a review of community feedback, the project team made minor changes to the final design to improve safety and amenity.

Key changes include:

  • a new roundabout on Illaroo Road at the Fairway Drive intersection to provide safe access to and from the northern foreshore
  • improved design of the area at the southern end of the bridge at Scenic Drive to maximise open space
  • closure of the intersection of Scenic Drive and Bridge Road to improve pedestrian safety and connectivity
  • providing a left turn lane from the Princes Highway into Pleasant Way
  • providing signalised pedestrian activated crossings at Illaroo and Bridge Roads to improve pedestrian and cyclist safety.

The detailed design overview map as well as more detailed designs for the northern and southern (5.51Mb) sides of the project are available to view in project documents.

Overview imageView a larger version of the map.

Urban design and landscape plan

The urban design and landscape plan shows how the new bridge connects with its wider environment. We have considered the existing natural landscape, strategic plans for the Shoalhaven River foreshore and Nowra CBD, and the historic Nowra Bridge.

Community information

Frequently asked questions

What is the Nowra Bridge Project?

The Nowra Bridge project provides a new four lane bridge over the Shoalhaven River and upgrades to over 1.7 kilometres of the Princes Highway, including improved intersections and additional lanes.

The $342 million project improves traffic flow and eases congestion on a major section of the Princes Highway and delivers safer, more reliable journeys within the Nowra-Bomaderry area.

The project’s need is based on the replacement of the existing historic southbound bridge which is in poor condition, has substantial maintenance costs, restrictions on overheight and overmass vehicles and has reached the end of its serviceable life.

Where is the project up to?

Fulton Hogan Construction was awarded the design and construction contract for the project and work started in 2020.

The new bridge was officially opened on 23 February 2023 and at this time, the historic bridge was retired from road traffic. 

In November 2023, work to place the final layer of asphalt and permanent line marking was completed which marked the end of major work on the Nowra Bridge project.

Minor work is continuing as we complete landscaping, small pavement and footpath work, and restore the project compounds and ancillary sites. 

The project is on track to be complete by mid 2024.

What is the cost of the project?

The $342 million Nowra Bridge project is jointly funded by the Australian and NSW Governments.

The NSW and Australian Governments have each committed $155 million towards construction, which is separate to funding provided for project planning, property acquisition and rehabilitation of the existing wrought iron truss bridge, which are all included as part of the full project cost.

How long will the project take to build?

The project is expected to be complete by mid 2024, weather permitting.

Construction

What are the construction hours?

Standard construction hours for the Nowra Bridge project are:

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

The majority of the bridge construction work will be done during standard construction hours. Work outside standard hours, including night work, will be required at times to minimise disruption to traffic flow throughout the life of the project.

We will notify road users and residents in advance of traffic changes and out-of-hours work. Electronic messaging signs and traffic alerts will be used to inform road users of traffic changes related to the project, especially those affecting the Princes Highway.

Community members and residents can also sign up to receive email updates on the Nowra Bridge.

How was the new bridge built?

The new four lane concrete bridge is around 360 metres long and is located upstream (west) of the existing bridges. The new concrete bridge carries northbound traffic and the existing concrete bridge (opened in 1981) is now used for southbound traffic.

Thirty-nine steel piles were driven into the river bed and the new bridge has nine piers across the river to match the existing bridges. Nineteen concrete double-T deck segments were cast at the Scenic Drive compound and were incrementally launched across the river until they reached the northern foreshore.

Due to the varying depth of water across the Shoalhaven River at this location, different construction methodologies were used.

Across the southern half of the river where water is shallow, a temporary rock platform provided a working area for bridge piling and foundation works. The rock platform extended into the river for approximately 130m and is about 45m wide.

A silt curtain was installed in the area and became operational before any rocks were placed in the waterway.

Across the northern half of the river, where the depth increases to around nine metres, works to install the piled foundation occurred by working off barges and boats.

What was the temporary rock platform required for?

The river is too shallow on the southern side to allow the use of a large barge for piling works. The temporary platform allowed the piling rig, crawler cranes and other heavy plant and equipment to operate safely to build the new bridge.

Although a large part of the river’s width was restricted, the main channel and deep water was unobstructed by the rock platform, so there was minimal effect on river and tidal flows. The temporary rock platform has been removed from the river now that bridge construction is complete and some of the material was reused elsewhere on the project.

What is piling and why is it required?

Piles create a strong foundation for the bridge by connecting the piers to a layer of soil or rock. The piling method used depends on the soil or rock type and the load the pile will support.

The northern-most pier was constructed using bored piles filled with concrete. This method is used as the depth to rock is around 10 metres. Driven piles were required at all other piers across the river where the depth to rock is up to 60 metres.

Driven piles are built by driving tubular steel cases into the ground using a large hammer on a piling rig. The piles are vibrated into the sediment and then driven by a hammer into the rock deep below the riverbed.

Why has the intersection of Scenic Drive and Bridge Road been closed to motorists?

The intersection of Scenic Drive and Bridge Road was closed in September 2020 to provide a safer working area during construction. The main bridge compound is located on Scenic Drive and there were daily heavy vehicle movements in the area.

Now major work on the project is complete, the intersection will remain closed and become a cul-de-sac. This was included in the detailed design for safety reasons.

With the new bridge being built on the western side of the existing bridges, the highway has also shifted west. If retained, the Scenic Drive and Bridge Road intersection would be too close to the new pedestrian crossing on Bridge Road. Vehicles turning left out of Scenic Drive would have limited sight and stopping distance to pedestrians. The right turn into Scenic Drive must also be removed due to insufficient queuing area on Bridge Road which would cause traffic and safety issues on the Princes Highway.

For more information view the Scenic Drive animation.

How will the community be impacted during construction?

With major work complete, the impacts and disruption to local and through traffic, including pedestrians and cyclists, is minimal.

While we aim to carry out work in a way that minimises delay and disruption, the community may experience some impacts as we complete the project.

Temporary lane closures may impact motorists as we complete finishing works in the road corridor, and temporary changes to shared paths while we complete concreting and footpath work may impact pedestrians and cyclists.

The community will be notified in advance of any temporary local road changes and detours.

Why is vegetation removal required?

Removal of vegetation at Moorhouse Park, Scenic Drive and other areas was required to make space for temporary work compounds and storage areas. Vegetation removal also occurred where power, water or other services are to be relocated. The project aims to minimise vegetation loss and reuse material across the project where possible.

The project team installed some habitat boxes for animals and birds in neighbouring Nowra woodland in 2020 to offset impacts from vegetation loss.

Will water quality in the Shoalhaven River be affected?

Water quality has been assessed for the Nowra Bridge project and water quality controls have been outlined for the construction and operation of the project.

A Soil and Water Management Plan has been prepared and included in the project’s Environmental Management Plan addressing construction risks such as soil erosion and resulting sedimentation of the Shoalhaven River and Bomaderry Creek, as well as fuel and other chemical leaks from plant and equipment.

The design includes water quality basins to treat stormwater runoff from the new northbound bridge.

Stormwater from the local road improvement works would be directed into the existing stormwater system.

Will you use local employment and businesses?

All expressions of interest for employment on the Nowra Bridge project are considered on a case-by-case and as-needs basis, with a number of local sub-contractors and suppliers from the Shoalhaven region already engaged. A competitive tendering process applies to all packages of work as is standard practice with large projects.

For certain aspects of work, subcontractors may need to be pre-qualified or registered under Transport for NSW systems. Fulton Hogan has also rolled out an Aboriginal workforce-training program modelled on the successful Infrastructure Skills Legacy Program in place on Transport for NSW construction projects.

Detailed design and urban design

What is the final design of the project?

The project team has used the recommendations from the submissions report of 2019 to help shape the final design.

The detailed design was displayed for community feedback in 2020. There were a number of design changes made since concept to improve safety, amenity and access.

Key features of the final design include:

  • upgrades to over 1.7 kilometres of the Princes highway to provide at least three lanes in each direction from Mattes Way to Moss Street.
  • a new four lane bridge for motorists travelling north, with the existing northbound bridge reconfigured to provide three lanes for motorists travelling south.
  • two right turn lanes into Illaroo Road from the Princes Highway and three lanes turning right and one dedicated left turn lane onto the highway.
  • two longer lanes for motorists turning right into Bridge Road and retention of the dedicated left turn lane from Bridge Road to the Princes Highway to travel north.
  • left turn only into Pleasant Way and a new local road built further south to connect the Princes Highway to Lyrebird Drive permitting left in and left out access.
  • a new roundabout on Illaroo Road at the Fairway Drive intersection to provide safe access to and from the northern foreshore
  • closure of the intersection of Scenic Drive and Bridge Road to improve pedestrian safety and connectivity
  • improved pedestrian and cyclist connectivity across the project including a new 3.5m shared path on the new bridge.

How will the Nowra Bridge project improve traffic flow?

All traffic lights will be coordinated and optimised in the project area and further south through Nowra. Bolong Road, Illaroo Road and Bridge Road intersections will allow for all traffic movements to improve traffic efficiency on the Princes Highway.

We recognise the community is interested in peak holiday season traffic volumes. Overall, the additional lanes, improved intersections and optimised traffic lights will improve capacity and reduce congestion on the highway and surrounding local roads.

The traffic modelling for the project has considered traffic growth up to the year 2046.

How will the project improve pedestrian and cyclist access?

There will be improved pedestrian and cyclist access across the project. A three and a half metre wide shared path on the western side of the new northbound bridge will connect to two and a half metre wide paths elsewhere across the project.

The project also improves east-west connections across the Princes Highway for pedestrians and cyclists by providing additional signalised crossings at the Bolong Road intersection as well as shared path underpasses at the southern foreshore, and a pedestrian stairway and path under the bridges on the northern side of the river.

What is the urban design and landscape plan?

The urban design and landscape plan shows how the new bridge connects with its wider environment. We have considered the existing natural landscape, strategic plans for the Shoalhaven River foreshore and Nowra CBD, and the historic Nowra Bridge.

Consultation

How has the community been involved in the development of the project?

We have been engaging and consulting with the community on the development of the Nowra Bridge project since 2013.

The Review of Environmental Factors (REF) was publicly displayed in 2018 and 109 responses were received during the display period. Most submissions were received from the community, including individuals, businesses and community groups. Submissions were also received from Shoalhaven City Council, Department of Primary Industries (Fisheries), NSW Environment Protection Authority, Office of Environment and Heritage, and Natural Resources Access Regulator.

In response to submissions from the community and following further design development since the display of the REF, changes to the REF and detailed design have occurred. A report detailing the submissions received was published in 2019.

Was a bypass of Nowra considered?

An additional four-lane bridge on the Princes Highway over the Shoalhaven River has been determined as the most effective way to improve traffic efficiency and reduce traffic delays on the stretch of the Princes Highway between Nowra and Bomaderry.

The project team carried out a wide range of detailed investigations to identify how to achieve this, including a bypass. However, traffic studies identified that about 85 per cent of the current trips travelling across the bridge have their origin and destination in the Nowra or Bomaderry area and would not use a bypass.

Construction of the new four-lane bridge would not preclude the future planning of a bypass if and when traffic demand arises.

Was a flyover or underpass considered at the Illaroo Road or Bridge Road intersections?

Grade-separated intersections have been assessed extensively during the development of the design. This included assessing how grade-separated intersections would impact on traffic flow on the Princes Highway and the local road network as well as the environmental impact.

An assessment of 11 grade-separated options was carried out for the proposal. The traffic modelling identified that many combinations of grade-separated intersection options on the northern and southern sides introduced inefficient and unsafe weave, merge and queuing issues that do not presently exist on the network.

While these would provide benefits to the local road network, they had the highest level of congestion on the Princes Highway compared to the other network options that were modelled.

What will happen to the old Nowra Bridge?

The historic southbound bridge is nearing the end of its serviceable life, has substantial maintenance costs and restrictions on over mass and over height vehicles.

Transport for NSW will work together with Shoalhaven City Council to repurpose the historic bridge following project completion to ensure it fits with council's broader plans for the foreshore.

Investigations and planning are currently under way for the rehabilitation of the historic bridge. 

 Project documents

Media releases

 

Contact us

For further information about this project, please contact:

Phone: 1800 331 713

Email:NowraBridgeProject@fultonhogan.com.au

Mail: Nowra Bridge project, PO Box 477 Wollongong NSW 2520