The Nowra Bridge project will provide 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 will improve traffic flow and ease congestion on a major section of the Princes Highway and deliver safer, more reliable journeys within the Nowra-Bomaderry area.
The project’s need is based on the replacement of the existing southbound bridge which is in poor condition, has substantial maintenance costs, restrictions on overheight and overmass vehicles and can only carry highway traffic for a limited time.
Fulton Hogan Construction was awarded the design and construction contract for the project and work started in 2020.
Major work started in June 2020 and has included site establishment, vegetation removal, utility relocations, putting in place pedestrian and cycle detours, building the temporary rock platform, implementing traffic changes on the Princes highway to establish work areas and starting earthworks for the new local road connecting to Lyrebird Drive.
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.
The project is expected to be complete by mid 2024, weather permitting.
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. However work outside standard hours including night work will be required to minimise disruption to traffic flow throughout the life of the project.
We will notify all 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 motorists of traffic changes related to the project, especially those affecting the Princes Highway.
Community members and residents can also register to be added to our email distribution list by sending an email with your details to NowraBridgeProject@fultonhogan.com.au
During the project there will be a number of changes to footpaths as we create work areas and carry out roadworks. These are required for the safety of pedestrians and cyclists and we will advise the community prior to any changes.
Footpath signs will be in place advising of closed paths and detour routes.
The new four lane concrete bridge will be around 360 metres long and is located upstream (west) of the existing bridges. The new concrete bridge will carry northbound traffic and the existing concrete bridge (opened in 1981) will be used for southbound traffic.
The new bridge will require 39 steel piles driven into the river bed and will have nine piers across the river to match the existing bridges. 19 concrete double-T deck segments will be cast at the Scenic Drive compound and will be incrementally launched across the river until the northern foreshore is reached.
Due to the varying depth of water across the Shoalhaven River at this location, different construction methodologies will be used.
Across the southern half of the river where water is shallow, a temporary rock platform provides a working area for bridge piling and foundation works. The rock platform extends into the river for approximately 130m and will be up to 45m wide.
A silt curtain will be installed and become operational before any rocks are 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 will occur by working off barges and boats.
A clearly marked marine safety exclusion zone is in place around 200 metres west (upstream) of the new bridge and 30m east (downstream) of the existing truss bridge.
The river is too shallow on the southern side to allow the use of a large barge for piling works. The temporary platform will allow 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 will be restricted, the main channel and deep water will be unobstructed by the rock platform, so there will be minimal effect on river and tidal flows. The temporary rock platform will be removed after bridge construction and some of the material will be reused elsewhere on the project. All piling on the northern side of the river will be done using large barges where the deeper water and channel makes this possible.
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 will be constructed using bored piles filled with concrete. This method is used as the depth to rock is around 10 metres. Driven piles will be 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 will be vibrated into the sediment and then driven by a hammer into the rock deep below the riverbed. This piling method is noisy and vibration will be felt in the surrounding area. We will make every effort to minimise during the work.
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 are daily heavy vehicle movements in the area.
When 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 will also shift 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.
A marine safety exclusion zone has been established around 200 metres west (upstream) of the new bridge and 30 metres east (downstream) of the truss bridge.
Water-based activities associated with work on the new bridge may require the restriction of watercraft movements for short periods. However, the navigational channel of the Shoalhaven River will be maintained during construction.
North Nowra Rotary Park on Illaroo Road will be closed to the public during project construction. In addition, sections of Greys Beach Reserve may be closed at times during construction.
Off-street parking will also be closed at several locations during construction, including the southern foreshore at Scenic Drive, parking spaces on Illaroo Road and part of the informal parking area at the Shoalhaven Entertainment Centre and Visitors Centre.
During construction of the Nowra Bridge project, work will be carried out in a way that it minimises delay and disruption to local and through traffic, including pedestrians and cyclists.
The Princes Highway and local roads such as Bolong Road, Illaroo Road and Bridge Road will generally remain open. However, there will be times when temporary lane closures and detours will be required.
During construction, there may be temporary increases to travel times for vehicles, cyclists and pedestrians due to temporary speed limit restrictions, detours and increases in the number of construction vehicles. The community will be notified in advance of any temporary local road changes and detours.
Pedestrian and cycle detours will also be in place to ensure work areas are safe. These detours will be signposted and the community will be notified in advance.
Removal of vegetation at Moorhouse Park, Scenic Drive and other areas is required to make space for temporary work compounds and storage areas. Vegetation removal will also occur 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 earlier this year to offset impacts from vegetation loss.
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 be 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.
There will be an increase in noise to some nearby properties while the bridge is being built. Every effort will be made to minimise noise during construction by:
- scheduling works to consider less sensitive time periods
- operate and maintain plant and equipment in an efficient and proper manner
- choosing lower noise construction techniques
- choosing lower noise plant and equipment
- site awareness and being considerate on work sites, such as avoiding dropping or dragging equipment and materials.
A Noise and Vibration Management Plan has been prepared as a part of the project’s Environmental Management Plan. This includes:
- noise and vibration monitoring and reporting
- arrangements for consultation
- construction scheduling to minimise noise impacts
- identification of controls to be adopted during construction
- contingency measures to be put in place in the event of unexpected noise issues during construction.
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 will also roll 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
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 June-August 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.
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.
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.
The urban design and landscape plan shows how the new bridge connects with its wider environment. We have considered the existing natural landscape, Nowra's future strategic river and CBD plans and the old Nowra Bridge.
We have been engaging and consulting with the community on the development of the Nowra Bridge Project since 2013.
The REF was publically 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.
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 current proposal would not preclude the future planning of a bypass if and when traffic demand arises.
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.
The existing southbound bridge is nearing the end of its serviceable life and can only carry highway traffic for a limited time, 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 old bridge following project completion to ensure it fits with council’s broader plans for the foreshore. Further investigations and studies into the repair work required will be carried out once traffic is removed from the existing bridge. The community will be consulted during this process.