Increased Safety and Capacity on the Gold Coast

With a fast-growing population, the $3.02 billion Coomera Connector Stage 1 project will increase safety and capacity by providing a new travel route for local traffic between Gold Coast communities, relieving pressure on the nearby Pacific Motorway (M1).

HDR and BG&E formed a design joint venture to provide engineering design services for the Stage 1 South section of the project. Our team delivered value engineering, preliminary and detailed design phase services (including traffic analysis, hydraulic analysis, road design, pavement design and structural design), facilitation of a construction contractor Early Tenderer Involvement (ETI) process, development of an Early Works package and more.

New Motorway, Including New Bridges

The Stage 1 South section of the Coomera Connector project will be constructed from Smith Street Motorway in Molendinar to Nerang-Broadbeach Road in Nerang, which is about four kilometres in total. The section requires three new bridges, including a large bridge crossing the Nerang River.

The new road will be constructed in a predominantly greenfield corridor as a four-lane road, with key interchanges, bridges, and other components designed to accommodate future upgrades. A shared-use path has also been designed along the entire length of the new road supporting active transport. 

Key challenges include soft soils in the floodplain, very hard rock in a 20-metre cutting, hydraulic sensitivities at Nerang River, and working within a corridor constrained by nearby rail lines, waterways, protected environmental areas, and private properties. As one portion of a larger project, our team also had to work closely with the team designing the Stage 1 Central section to ensure a coordinated interface.

Environmental & Sustainability Focused Solutions

The team developed the design in accordance with the approvals obtained from the Australian federal government under the Environment Protection and Biodiversity Conservation (EPBC) Act and documented in the Public Environmental Report (PER) and offset area management plan. During the design development, the requirements of the PER, including project boundary, were assessed and modified as necessary to meet the project requirements and confirm constructability of the solution. Supplementary environmental investigations, surveys and documentation were completed to support the design and implementation of approval requirements. Planning approvals under Queensland state legislation were also sought, with engineering and environmental justification, for temporary and permanent waterway barrier works and marine plant removal.

The design met Transport and Main Road’s sustainability commitment through careful choice of materials, reduction in material usage and recycling onsite or offsite, along with seeking to incorporate sustainable construction techniques and other initiatives. This was documented in our submission to the Infrastructure Sustainability Council (ISC) with a goal to achieve an Excellent rating. 

The design also considered resilience through consideration of climate change in flood modelling and material usage to achieve desired design lives, as well as selection and use of landscaping and shading to reduce heat island effects.

Design of the main works package has been completed and the contract for the main construction was awarded in late March 2025.