Suburban Rail Loop (SRL) is the biggest public transport project in Australia. It aims to build a 90 km loop linking every major rail line from the Frankston to the Werribee line via the airport, better connecting Victorians to jobs, retail, education, health services and each other.

The project will be executed in three stages with $2.2 billion already allocated to kickstart construction. Stage 1 of the SRL aims to connect six stations from Cheltenham to Box Hill.


Middleton Group had the opportunity of being involved in Victoria’s largest-ever infrastructure project providing power advisory services and electromagnetic compatibility advisory services.

Our responsibilities included optioneering and developing optimal power solutions for the traction network as well as verifying traction power modelling, earthing, bonding and electromagnetic compatibility.


To deliver on our promises, we established a team of subject matter experts to manage the power supply for the tunnel boring machines, oversee the HV supplies for the traction substations, perform optioneering to power the trains and review traction power modelling results. In terms of electromagnetic compatibility, our team reviewed the approach taken to identify sensitive receiver along the rail alignment and provided expertise advise into the stakeholder engagement process.


Through working collaboratively with our client, contractors and relevant stakeholders, we endeavoured to provide the best outcomes for this project. We ensured all traction power, distribution power and connections options were assessed to arrive at the optimal solution. Our reviews ensured design solutions were fit for purpose, safe, reliable, maintainable and provided the best value for money for the state. Our subject matter experts also validated the sensitive receivers identified and ensured that stakeholders were appropriately managed throughout the different stages of the project.