Local crews install the flat‑pack bridge at Rowlands Creek, a design that speeds up construction at remote sites
Tweed Shire Council is right now installing an innovative bridge at Rowlands Creek that's the longest of its type for the Tweed Shire — a flat-pack design that cuts construction time in half and keeps jobs local.
Helping to protect threatened species near a national park boundary, the bridge is engineered to withstand the kind of floodwaters that destroyed the previous culvert crossing.
The 13.7 metre bridge arrives on site ready to assemble. The abutments go in first, anchored deep into the bedrock on each bank. Once they're secure, the steel spans are lifted into place by crane. After that, the concrete truck rolls in to pour the deck and the structure is completed. Work started in February and completion is due in June, weather permitting.
At a remote site like Rowlands Creek, constructing a bridge would normally take several months. Using a prefabricated flat‑pack design has cut the overall construction time in half, with the bridge span itself completed in just two weeks.
Precision fabrication takes place in a controlled yard rather than on a remote creek bank, meaning the structure arrives on site ready to install, without sacrificing quality. The remaining construction time is focused on essential site works such as foundations, bank protection and approach works needed to support the bridge and prepare it for future floods.
Mullumbimby-based Ireland Civil is doing the installation as part of a $2.1 million contract, covering 3 bridge replacements across the Shire. Because the complex fabrication is handled off-site by Inquik Bridging Systems, local crews can take on the build without specialist equipment. The knowledge stays in the prefab yard. The construction jobs stay in the Tweed.
The open‑span bridge at Rowlands Creek allows natural water flow, improving movement for fish and other native species beneath the structure.
"Roads and bridges, people drive past them every day and don't give them a second thought," said Kurt Heidecker, Tweed Shire Council's Project Director of Flood Restoration.
"But when you get into the detail of how they work, every one of these projects has something in it. This one has prefabrication that changes what's possible in remote locations, is engineered to withstand floods that can strip a landscape bare, while not affecting native species. There's more going on here than most people realise," he said.
The Rowlands Creek site borders a national park, adding an extra layer of environmental responsibility to the project. The bridge has been designed and built to protect the Giant Barred Frog and the Southern Purple Spotted Gudgeon fish, vulnerable and threatened species found at this crossing.
The previous flow through culvert pipes created a narrow, fast channel that small fish and amphibians couldn't swim against. This new open bridge span preserves natural water flow, allowing species to move freely through the waterway.
The bridge is replacing a structure that didn't survive the floods, and the site tells the story. Cleanup workers arriving on site after the 2022 flood described a landscape stripped of all vegetation by floodwaters that were unbelievably deep, fast and high velocity.
This new bridge is designed for that. The abutments are drilled into rock. Massive boulders line the banks for scour protection. And when floodwater rises, the bridge goes under with it —protected by galvanised steel formwork that absorbs and spreads the impact when debris strikes, rather than damaging the concrete bridge abutments.
"It's a really neat solution," Mr Heidecker said.
"The fish can travel as they need to. The structure is built to handle what this creek throws at it. And we've got a local company doing the work."
