Infrastructure resilience work - bridges

Project: Replacing timber bridges with more resilient structures

Funding:

  • $7.1m from the NSW Government’s Fixing Country Bridges Program
  • $900,000 from the Australian Government's Bridges Renewal Program

Timeframe: 2021 to 2023

Last updated: December 2022

Details

We are working to: replace eight timber bridges:

  • five along Narooma’s Wagonga Scenic Drive
  • the Tilba Tilba Creek, Potato Point and Silo Farm bridges.

Benefits to the community:

  • The replacements will feature steel and concrete, making them more capable of withstanding natural disasters.
  • They will also carry higher loads, improving safety and resilience for our road network.

With recent natural disasters taking such a heavy toll across the Eurobodalla, we are now more than ever determined to increase the resilience of our infrastructure. We are taking a proactive approach with a goal to future-proof our rural road network to help keep communities safe and linked together.

On top off the 18 fire and flood damaged bridge rebuilds we will also replace a further eight timber bridges: five along Narooma’s Wagonga Scenic Drive, and the Tilba Tilba Creek, Potato Point and Silo Farm bridges.

We’ll use the innovative InQuik modular bridging systems that have featured heavily in the recent rebuilds. Large, prefabricated components will be manufactured off-site, substantially reducing construction times. Where possible, we will use regional contractors for the installation work.

Our planning works included assessing the position and alignment of each bridge before construction. We have considered land ownership, local heritage, environmental assessments, ease of access for long vehicles and continued access during construction. Most bridges will be rebuilt alongside the existing ones, meaning the roads will remain open during construction. Where road closures cannot be avoided, we will advertise details via electronic roadside signs and on our website.

To attract the funding for the work, we joined with our colleagues from adjoining shires to develop an innovative memorandum-of-understanding that delivered many bridges across our region. It’s a first for regional NSW, and a model that has since been taken up by other local government partnerships across NSW. We’re also hoping to secure funding for more bridge replacements under round two of the program.

Check out the details and see where we are up to with each bridge.

Narooma’s Wagonga Scenic Drive winds its way through rural residential areas, agricultural land and state forest. The road is also a popular tourist route providing access to the upper waters of Wagonga Inlet. The road features five timber bridges, all at risk of fire and flood.

Replacing the bridges with more resilient structures will allow for safer and more reliable crossings for residents, tourists, delivery services, emergency services and maintenance staff. The likelihood of residents being trapped in or away from their homes will be significantly reduced as will the need for long detours.

We are building the new Clarksons Bridge upstream of the existing bridge. Cobra and Punkalla bridges will be located to the downstream side, positioned parallel to the existing bridges.

Land ownership and heritage constraints determined that the alignment of Grumleys Bridge could not be changed. Therefore, a full road closure was needed to build the new bridge in the same position.

The large, prefabricated components have been delivered to all sites. We are off to a good start with construction underway at Cowdroys, Cobra, Grumleys and Clarksons bridges. Once construction is complete, the road will be realigned to tie in with the new bridges and the old bridges will be demolished.

A construction site shows aluminum bridge abutments in place.
Cowdroys Bridge: under construction in March 2022

A concrete bridge is under constructin next to a smaller, timber bridge.
Cobra Bridge:
Underway in May 2022

The Tilba Tilba Creek Bridge is located on Corkhill Drive; a major tourist route providing access to the historic Tilba villages and district as well as Gulaga National Park. We have identified the bridge replacement as a priority due to its declining condition and high volume of traffic.

We have completed design for a new concrete bridge that will result in safer, quieter, and more reliable access for residents, tourists, and school buses. The bridge will be stronger, longer, and wider and include a shared pathway to provide a safe crossing area for pedestrians and cyclists.

We are in the process of consulting with the Tilba community and expect to order the bridge components shortly. The new bridge will be installed once the old bridge is removed, minimising impact on the surrounding area by maintaining the current road alignment. Consequently, through traffic will not be possible for the duration of the project.

We expect the work to take approximately two months to complete. Once we have locked in dates we will inform the community and provide directional signage.

A sealed road with a bridge leads through a forested area
Tilba Tilba Creek Bridge: Located 600m from the Princes Highway, just before Foxglove Gardens and the turnoff to the sports grounds

The Potato Point Bridge is located on a road providing the only two-wheel drive access to a popular beach and holiday park.

Our contractors have replaced the timber bridge using concrete with a stainless-steel shell to provide protection against the harsh saltwater environment. We chose to use the innovative technique in order to significantly increase the life of the asset.

A short timber bridge leads over a coastal creek
Potato Point Bridge: The old timber bridge crosses a coastal creek

A temporary bridge spans across a creek
Temporary crossing: Contractors demolished the old bridge and provided a temporary structure to retain access to the holiday park

Silo Farm Bridge crosses the Tuross River and is an integral part of the access route for two dairy farms west of Bodalla. The bridge is typically submerged several times per year due to high river flows during wet weather. Not only are residents and emergency services unable to get in or out of the area, but milk trucks cannot access the dairy farms. The milk cannot be stored on-site for more than two days, and farmers are left with no choice but to dump thousands of litres of milk. The result is a loss of income for the farmers, loss of milk supply for the community and adverse impacts on the local environment.

We will replace Silo Farm Bridge with a higher structure capable of providing improved access during future floods. During the February/March 2022 flood the dairy farmers dumped 107,097L of milk due to a lack of access. If the same event were to occur with the new bridge in place, the farmers would be able to store their milk for the brief time until the bridge was again trafficable.

The design for this new bridge is complete and construction is set to occur in 2023.

A long low timber bridge crosses a river
Silo Farm Bridge:
The  low-lying timber bridge often goes underwater when it rains

More info

For more information about replacing the timber bridges, please contact the Project Engineer, Lew Oldfield: