Goomboorian is a rural locality 20km north-east of Gympie on Queensland’s Sunshine Coast. Bordering Goomboorian’s east is the Great Sandy National Park, home to hiking trails and the last known coastal emu. For many residents and motorists alike, the Stephan Road Bridge has been a popular staple with generations of locals using the bridge to communicate to and from Gympie.
In March 2020 the Gympie Regional Council aimed to refurbish and rejuvenate the tired bridge, setting an ambitious 8-week timeframe to complete works.
“It’s incredibly important our infrastructure not only functions well, but is also cost effective,” said Mayor of the Gympie region, Glen Hartwig. “Our rural residents rely on safe timber bridges during their daily commutes or to access properties.
“It’s vital they are safe and made from material that is long lasting,” he said.
The bridge itself measures 11.2m x 4.4m in total span and crosses the Tagigan Creek. For the Gympie Regional Council, one of a growing number of Australian local governments that have embraced Wood Encouragement Policies, the selection of a structurally durable, termite proof timber system was an important consideration.
According to Peter Robinson PNG Forest Products General Manager of Strategy and Development, the bridge was erected in two lifts, allowing for works to be delivered on time with minimal disturbance to residents.
“The use of a modular system accelerated the construction and installation of the timber structure, while the employment of ACQ (Alkaline Copper Quaternary) veneer makes the bridge structurally durable, protected from rotting and termite infestation, whilst able to support heavy duty transport.
“The Engineered Wood product modular structure was placed by a mobile crane, locked together in place and bolted to pre-prepared abutments.
“The use of ACQ treatment is an important feature, with the veneer treated prior to fabrication into final design; this ensures 100% protection. ACQ treatment is light brown in colour without the chromium and arsenic that is found in CCA (Copper Chromium Arsenic),” Mr. Robinson said.
The peak body for the timber industry in Queensland has welcomed this project as a demonstration of the versatility and innovation of using engineered wood products in bridge construction.
The CEO of Timber Queensland, Mick Stephens, said: “Using prefabricated timber systems in bridges is gaining greater market recognition due to their inherent strength, light weight and low carbon emissions footprint compared to other construction materials. We have been working with many local councils and the State Government on promoting the economic and environmental benefits of timber, and the Gympie Council is to be commended for putting into action this project with a direct link to its Wood Encouragement Policy”.