The Gap Road level crossing removal in Sunbury is delivering significant environmental and social outcomes with innovative design improvements and First Nations engagement.
Thanks to an Environment, Social and Governance (ESG)-embedded design approach, the Gap Road level crossing removal, a key part of Rail Projects Victoria’s Sunbury Line Upgrade, will deliver safer, more sustainable, and community-centred outcomes.
The project will replace the Gap Road level crossing with a road-under-rail and a rail bridge design. Working alongside CPB Contractors, John Holland, RPV and Metro Trains Melbourne as part of the Rail Network Alliance (RNA), AECOM provided detailed design services as the lead designer for this key project.
Community-driven design
The structural design, underpinned by principles of crime prevention through environmental design (CPTED), delivered a two-span bridge that improved sightlines, increased lighting and exit points and enabled greater wayfinding. The design is also more aesthetic, with robust cladding and limited flat surfaces to deter vandalism and graffiti.
The change from a four-span bridge to a two-span bridge was initially deemed impossible. However, AECOM, alongside RNA partners, overcame significant technical challenges presented by a two-span bridge design and found ways to achieve design improvements, manage resources efficiently, and reduce the amount of materials used.
The design also incorporated greater landscaping and used high solar reflectance finishing materials in the path to help reduce urban heat and create a more pleasant place for the community on hot days.
Exceeding sustainability objectives
Changing the design to a two-span bridge reduced the bridge length, resulting in reductions in materials and the width of excavation required. These design improvements also reduced the embodied greenhouse gas emissions from the reference design and the emissions associated with excavation works and transport.
AECOM engaged with design team specialists to investigate sustainability initiatives, including the use of glass-fibre reinforcing material to reduce steel consumption, water sensitive urban design, including the improvement of stormwater quality, management of peak stormwater flow and groundwater recharge, and recycled glass sand as bedding material for all drainage piping.
The improved bridge design significantly reduced embodied carbon emissions by 988 tCO2e. The improvements have also considerably reduced the need for concrete (766m3), steel reinforcement (200 tonnes), and the fuel required for construction activities.
Partnering to celebrate First Nations culture
RNA partnered with Indigenous artist Teena Moffatt to celebrate and recognise First Nations culture and heritage. Her artwork, placed on the cladding of the bridge, is a centrepiece of the design.
Teena’s artwork is inspired by the significant geographical, archaeological, and geological sites within Sunbury and its surrounds – some of which date back 400 million years. It depicts the interwoven relationship between plants, animals, and people, with an undulating line running through the middle of the artwork representing the Sunbury Line and its stations and the Manna Gum leaf that, in Wurundjeri tradition, is gifted to travellers - with the bearer then promising only to take that which can be given back from Wurundjeri Country.