January 2021 update
Work is well and truly underway with the bridge foundations completed in late December. These foundations involve the drilling of large circular holes within the underlying rock and the installation of reinforced concrete columns called piles.
The construction of above ground columns and the abutments will commence in 2021. The heavy rain experienced in late December raised the level of the Namoi River just above the central working platform. This was expected and the worksite prepared for the ingress of water. A few days are required this week to clean-up the site but there has been minimal interruption.
The road work recommenced this week and subsoil drains are currently being installed along the pavement from the bridge to Charles Street with sub-base and base granular pavement material being installed thereafter.
Works will progress into Rowan Street within the next few weeks. Once the road is completed in Rowan Street and sealed, traffic on Manilla Road will be diverted down Rowan Street and across on Charles Street to allow the intersection of Barraba Street and Manilla Road to be upgraded.
Roadworks are expected to be largely complete in March. Bridgeworks are expected to be completed in June with the opening of the new crossing..
The new bridge and road approaches have been modelled by a specialist hydrology consultant for storm events up to a 2000 year event.
The 100 year flood level has reduced significantly since the construction of Split Rock Dam.
The modelling has shown that the bridge has a negligible impact on the increase in 100 year flood levels in the surrounding areas.
The bridge and road approaches have been found to be trafficable for the 100 year flood event. This is the reason for the project name having been changed from the Manilla Low Level Crossing.
Similarly to flooding, the impact to residents along the new road alignment, when the road is completed and open to traffic, has been modelled by a specialist consultant – a specialist in acoustics and noise modelling for infrastructure projects.
A computer model was created by the consultant to identify the existing and predicted future noise levels along the new route. Noise loggers were used at several locations to verify and validate the model accurately predicts the existing noise levels to give confidence in the future noise level predictions.
The criteria used for the assessment of whether homes required noise mitigation measures is the NSW Road Noise Policy (EPA, 2011). The modelling has identified several properties that require noise mitigation works under the At Home Noise Treatment program.
Properties not part of this program have been shown to not require noise mitigation as per the NSW Road Noise Policy (EPA, 2011).
To assess the environmental impact of the project, a Review of Environmental Factors (REF) has been prepared by a group of specialist consultants.
The preparation of an REF is in accordance with Part 5 of the Environmental Planning & Assessment Act 1979.
The REF makes an assessment of the ecological, cultural, planning, legislative, and noise impacts of the project, with control measures nominated for implementation as required.
No major environmental constraints were identified within the REF.
A 60km/hr speed limit has been nominated for the new road between the new bridge and Charles Street. Other sections of the road will be at 50km/hr. A markup of these areas is provided below.
Appropriate speed limits are determined as per the NSW Speed Zoning Guidelines (Transport for NSW, 2011) and are ultimately selected by Transport for NSW.
The new Manilla Bridge and road upgrade will follow a route using Arthur Street and Rowan Street.
A route suggested by community members using Langworthys Lane and River Street was also reviewed but it had several design issues, explained in the conversation comments below, which meant it was not a feasible option.
Now the preferred route has been announced the detailed design can start. It will take about six months and include:
- Completion of Topographical survey;
- Completion of the flood modelling;
- Geotechnical investigations for the road and bridge foundations;
- Review of Environmental Factors (REF) report; and
- Road and bridge detailed design.
Improving our Road Network
About the Project
Tamworth Regional Council has prioritised the need for a low level crossing in Manilla and has recently secured significant state government funding for this key piece of infrastructure.
The existing heritage listed Manilla Bridge which crosses the Namoi River in Manilla presents a challenge for all vehicles. The length of the bridge (approximately 300m) means it is not always easy or safe to prepare for on-coming traffic. Heavy vehicles are currently required to give way to passenger vehicles and the length of the bridge makes it very difficult for heavy vehicles to determine when it is safe to cross. Upon completion of the project RMS will retain ownership of the bridge.
The proposed Namoi River Crossing will be four metres wider than the existing bridge. It is a necessary piece of infrastructure which will improve the road network, enabling future economic development and improving the safety for the community and tourists to the region.
The crossing will improve efficiencies for local, regional and interstate transport companies, as well as the agricultural sector that are reliant on the transport industry.
Design and Location
The project will alleviate the volume of heavy traffic from the existing Manilla Bridge and the detour through local roads, directing it to the proposed low level Bridge which will run parallel to the existing bridge in Arthur Street and align with Manilla Road (MR63) to the South.
The design for the bridge is in the early stages.
The preferred route is via Arthur and Rowan Street. This route offers significant safety improvements and reduces possible noise impacts compared to the other route options because heavy vehicles in particular won’t need to come to a stop to turn the corners. Roads and Maritime Services (RMS) has indicated this road will become Main Road 63 (or Fossickers Way) upon completion of construction.
Arthur Street, Rowan Street and other local roads will need some modification to suit the geometry of the preferred route and these modifications are also shown in the image below.
- In 1880 there was a petition sent to Government requesting a high-level bridge over the Namoi River at Manilla.
- The Minister for Public Works is met by Manilla deputation requesting go-ahead in traffic bridge in 1881.
- 1884 GH Royce & Co begins construction of the Manilla bridge.
- 1886 Namoi River bridge work completed linking North and South Manilla.
The Manilla Bridge was built in 1886, designed and constructed to the traffic conditions at the time, which is thought to be a 16 Tonne traction engine. Since the 1800’s, vehicle loading and safety standards have changed significantly.
Baiada Poultry received development approval in 2016 for the development of a large scale broiler farm near Manilla which includes 70 sheds across five farms. Baiada faced great difficulty with their development application due to the limitations of local road infrastructure being able to cope with the level of activity this organisation draws.
Questions and Answers
Residents of Manilla have told us through our Annual Operational Plan community consultations over the last 10 years about how the current bridge does not meet the community’s needs. Council has looked for ways to address the issue. When an opportunity for State Government funding became available, Council submitted an application.
Council regularly applies for funding and applications are not always successful. However, once an application is successful Council works with the funding partner to announce the news as soon as possible.
There have been preliminary investigations to find suitable sites for a second river crossing in Manilla, but Council was not able to start work to take the bridge concept to a detailed design until funding was secured. The site of the bridge is based on providing the shortest route for through traffic to reduce the construction cost. Longer routes would cost significantly more and we would not have received the funding.
It was always planned that once some route options for the road tie in’s were identified, Council would discuss with the local community. A final decision on the preferred alignment will be made following this meeting and once the remaining constraints have been resolved.
It is expected the bridge will cross the Namoi River parallel to but in the vicinity upstream of the existing Manilla Bridge in the Arthur Street road reserve. The bridge will be approximately 140 metres long and will transition to a road either side to tie in with the existing road network
There are several aspects of the design that need to be resolved before detailed design and can be finalised. Discussions are ongoing between Council and Roads and Maritime Services and the final decision on the road alignment will be made by TRC and RMS after consideration of the constraints and impacts of each option. The community will also be involved through both direct one-on-one consultation (where applicable) and events like the March 6 Community Information Session at Manilla’s Small Town Hall.
Manilla Road (Main Road 63) and is owned and maintained by Road and Maritime Services (RMS). The new road and bridge will become part of that road network and also be owned and maintained by RMS.
The existing bridge will remain in use for local traffic. As the bridge is on the RMS Heritage Bridge register, RMS will remain as the owner of the existing bridge.
The preferred route is via Arthur Street and Rowan Street. This route offers significant safety improvements and reduces possible noise impacts compared to the four other route options considered in the concept design.
It is not expected that traffic travelling through Manilla will dramatically increase as a result of having a second river crossing. However, one of the reasons for constructing the bridge is to provide better connectivity within the Region to allow future economic growth which will see the majority of heavy vehicles using this route rather than the existing detour via Rangari Road.
The Manilla community has identified weight limitations and the narrow width of the existing Manilla Bridge as an impediment to development. Residents and road users are also concerned about safety issues related to heavy vehicles using the existing bridge or detouring through the local road network. The lack of adequate road infrastructure is also impacting on the road transport industry and deterring agricultural investment and expansion in the Region.
It is to be expected traffic volumes will increase into the future as the Region and Manilla itself grows, but the new proposed crossing will create a safer route for all road users.
Noise levels can be managed through design methods and through additional controls. A Review of Environmental Factors Report will assess the current noise levels, and determine the predicted noise levels once the road is opened. Although the level of noise will be increased compared to the current situation, the preference will be to keep the predicted noise levels below the allowable threshold. Where this is possible, no additional noise mitigation measures will be adopted. If required, we will investigate noise mitigation measures will the affected residents.
The noise can also be mitigated through the detailed design stage. The steeper the road, the louder the noise from heavy vehicles as they accelerate or decelerate. The design will consider as flat a grade as possible.
Residents will always be able to access their property both during and after construction. Impacts during construction will be communicated with the residents closer to the commencement of construction.
Council will continue to update residents about the project as it proceeds. We have already written letters to Manilla residents and we held a community information session at the Manilla Small Town Hall on March 6, 2019. Our efforts to keep the community informed will continue.
Please check back to this page for any project updates.