The new Riverwalk on Brisbane River, from the City Reach Boardwalk to Bunya Walk in the Botanic Gardens, is an accessible thoroughfare that enhances the journey for commuters. The previous connection was a conflict point: it was narrow and unable to cater for cyclist and pedestrian traffic.
The two-way segregated thorough fare enables commuters and visitors to enjoy Brisbane River during peak times. The Riverwalk design, including wayfinding signage and landscaped paths, accommodates pedestrians of all ages and abilities and give cyclists a designated lane.
There is also a river access point for a range of vessels.
Arup’s teams provided a highly detailed visualisation to assist Brisbane City Council engage with stakeholders and the community about the Riverwalk project.
187m Long pathway
Animation brings the Riverwalk to life
Our digital specialists generated a range of outputs: a photomontage, an animation, a digital project tour and a virtual reality experience for Brisbane City Council.
Our visualisation team first created the photomontage (detailed images of the new Riverwalk), followed by a media-quality animation showcasing the Riverwalk and River Hub which highlights key design features including the proposed structures, civil design, landscaping, street furniture, signage and feature lighting.
The digital project tour (viewed in a secure web-browser on desktop and mobile devices) allows users to experience the proposed design by navigating to predetermined points for closer inspection.
The virtual reality experience allowed designers, engineers and our client to navigate through, interact with and explore the proposed design in a fully immersive environment.
Using digital solutions to bring our projects to life allows our design teams, clients and the community to experience the projects before they are built which helps to facilitate improved project outcomes and community benefits. ”Bob Donker Senior Technician
Brisbane City Council released the animation to the community through its media channels, bringing to life the proposed development that will position this section of the Brisbane River and the greater metropolis as a safe, must-visit destination.
The animation reveals an aerial view of the city, then descends towards Brisbane River, with identified landmarks orienting the viewer. The animation then dips and hovers just above the City Botanic Gardens, Bunya Walk and Gardens Point Boat Harbour.
The viewer then sees the Riverwalk and its surrounds from various locations, reflecting real-world dimensions. One segment depicts a foreshore walk under the proposed elevated bridge section, offering views of the city. Another has the view of Storey Bridge from the Bunya Walk, placing the viewer within a true-to-life setting.
We included a night time lighting design for the Riverwalk, showing how the new infrastructure could be used in the late evening.
To produce the animation, the new structures and civil design models were combined with existing contextual structures in a specialised animation software application. These models were then textured and animated, and finally rendered and composed in video editing software.
An accessible design to make full use of the river foreshore
Our engineering team designed the Riverwalk to be accessible by people with differing mobilities while also meeting key infrastructure points.
Our detailed designs were in keeping with the character of the area, with a minimal design aesthetic for the Riverwalk which would not detract from the surrounding vista of the City Botanic Gardens. We ensured our design would also align with future planning and development in the area.
The Riverwalk provides seamless connectivity between two recreational and commuter shared paths of the City Botanic Gardens and City Reach Boardwalk. In the future, it will become an urban hub for active and river transport. ”Eliza Howell Queensland Civil Structures Leader
Design for constructability, enhanced durability and reduced
Design considerations include flood risk management, sediment levels, risks of damaging under-water infrastructure and the durability of existing infrastructure.
The underside of the bridge deck is in the salt-water tidal zone, posing a problem with traditional forms of precast construction which would typically require bearings.
Replacing bearings in this zone is difficult due to the shallow height under the bridge and the limited accessibility due to the tides. In addition, the bearings would be subject to continued wetting and drying in the tidal zone – substantially reducing their operational life.
We designed an ‘integral bridge’ structure, that would still enable the use of standard and widely available precast elements for the bridge deck. This design eliminated the use of bearings, greatly reducing maintenance costs on the bridge’s 100-year design life.
Our integral bridge design has driven steel piles with a reinforced concrete shaft – instead of bored piles with a rock socket. This pile type allows the construction barge to sit further away from site in deeper water, substantially increasing construction productivity (as piling operations are no longer restricted by falling tides).
Designing an elevated walkway in the shallow waters of Brisbane River required analysis of underground pipelines and potential conflict points. Our design ensured that bearing piles would not interfere with the telecommunications conduit (that services the CBD) or pose a risk of damaging under-water pipelines.
The impact of flow on the Riverwalk
The Riverwalk runs parallel to the foreshore and is consequently labelled a non-traditional structure. No current industry guidance exists for hydraulic modelling of structures of this form.
The existing process for modelling traditional bridges (aligned perpendicular across a waterway) could not be easily modified for the Riverwalk structure, as there are no design variation guidelines to follow. The current broad application of hydraulic loss coefficients therefore failed to accurately describe the interaction between the bridge and flows.
Our engineers applied a new hydraulic engineering process using software algorithms to assess hydraulic losses for this structure. This allowed us to simulate changes to flow velocity and turbulence for a non-traditional structure aligned parallel to the direction of flow.
The process relied on sensitivity testing and consultation with bridge hydraulic specialists to develop the most appropriate solution for the Riverwalk to optimise the bridge, pier designs and geometries for trial bridge designs.
Our feasible solution aligning the project’s cost, constructability and flood impact (upstream and downstream) was approved by Brisbane City Council.