Australian Botanic Gardens Shepparton Bridge

Australian Botanic Gardens Shepparton Bridge.


Client	Greater Shepparton City Council
State	Victoria

Community connection ‘blooms’ at Australian Botanic Gardens.

Since opening in 2011, the 22.5-hectare Australian Botanic Gardens has become a much-loved regional tourist destination in the Goulburn Valley in north-eastern Victoria.

Following an open tender, Greater Shepparton City Council appointed Fleetwood as lead contractor to design and deliver a custom 55-metre suspension bridge across the Broken River, supported by a series of boardwalks connecting the Botanic Gardens to the Shepparton town centre.

Despite numerous challenges – including unstable embankments, repeated flooding, Covid-19 border closures and even a magnitude 6.0 earthquake! – all structures were successfully delivered as envisioned, with the main bridge officially opening to the public in November 2021.

Our involvement.

Fleetwood was appointed in June 2020 following an open tender which included detailed concept drawings for the new bridge.

As the lead contractor we were responsible for overseeing the full design and construct process, collaborating closely with Greater Shepparton City Council throughout.

Our involvement included early site investigations and geotech studies, as well as all engineering, shop detailing, material specification (including sourcing specialised cables from Europe with 32-week lead times), manufacturing, transportation, pre-assembly and installation for each of the structures.

We were also responsible for managing approvals with the local water authority. The main suspension bridge was completed in December 2021 with the full project opening in January 2022.

How does this project inspire people to love the outdoors?

Enjoying the Australian Botanic Gardens has never been easier or more inviting. Thousands of Shepparton residents and visitors are already using the new bridge and boardwalks every week for both relaxation and exercise.

The structures also provide a direct connection between the homes on the other side of the Botanic Gardens and the Shepparton town centre, creating a convenient new community thoroughfare.

Design Challenge

Historical flood data indicated the new bridge needed to sit high above the river level, at 13 metres, requiring a significant 55-metre single span. This presented numerous design challenges, particularly in minimising the environmental impact of such a large structure.

To preserve the established gum trees on the riverbanks and approaches, the bridge needed to be designed in a way that would allow for efficient installation (despite limited access), while the finished form also needed to blend in comfortably with the existing tree canopy.
Construction Challenge

Site conditions were difficult, and often treacherous, along the Broken River with significant rain and flooding experienced during the bridge’s construction. To minimise disruptions to the Australian Botanic Gardens – which remained open at all times – the bulk of work was completed from the township side.

A particular challenge was safely maneuvering the 250-tonne crane necessary to install the bridge cables, without striking or damaging the surrounding gum trees – a task made even trickier when the site was shaken by an earthquake mid-install with the 70m fly boom fully extended on 27 September 2021.

Another complication was resourcing, with Covid-19 border closures limiting the availability of specialised installation and rigging crews certified to work at the required heights.
Innovations

Suspension bridges typically require adjusting throughout their life. To make this process as simple as possible, we adopted an innovative design where the bearer and balustrade column were one assembly. This allowed for adjustments to be made at hand-height, rather than having to reach through the bearer.

Another innovation was the use of a custom connection/slip joint with one long cable that delivered cost savings to the project.
Features
- 55-metre custom suspension bridge
- Twin galvanized steel towers
- Imported 107-metre galfan galvanized tower cables
- Childproof galvanized balustrade panels
- 50-metre custom approach boardwalks x2
- 96-metre MARS™ boardwalk
- 300 metres of asphalt paths
Safety & Risk Considerations

This was a complex project with many inherent risks. Site instability and river levels were constantly monitored, especially given persistent wet weather.

Careful attention was paid to the location of the surrounding gumtrees (and their canopies) to avoid equipment strikes, accidents and habitat damage.

With crews working at heights of up to 13 metres, installation also required highly specialised rigging and harnessing techniques, which were refined by conducting on-site lift and assembly studies.
Sustainability Considerations

With its abundance of native flora and fauna, it was essential for the new bridge and boardwalks to sit comfortably within the existing habitat of the Australian Botanic Gardens, both visually and structurally. This required minimally-invasive designs and durable materials that would deliver long operational life (50+ years) while requiring low ongoing maintenance, little more than general visual checks and occasional adjustments.