Turning plastic waste into railway infrastructure: How SEPA solved a soil challenge

The South Eastern Program Alliance (SEPA), a partnership between Level Crossing Removal Project (LXRP), Laing O'Rourke, Jacobs, Metro Trains Melbourne and V/Line, delivers major rail infrastructure upgrades across Melbourne, removing dangerous level crossings and enhancing train services. As part of this work, SEPA is upgrading the South Dynon Train Maintenance Facility in West Melbourne: a critical hub for servicing Victoria's growing regional train fleet.

When our SEPA team needed to install critical cables across areas of contaminated land at South Dynon, we faced a potentially costly problem. Traditional methods would mean digging up thousands of cubic metres of contaminated soil. This approach would be expensive, time-consuming, and damaging for the environment.

Instead, we found a game-changing solution: TufDuct, a cable protection system made entirely from recycled plastic waste that requires minimal excavation compared to traditional buried conduits.

A Smarter Solution from Waste

The South Dynon Train Maintenance Facility upgrade required extensive cable networks to power signals, communications, and electrical systems. SEPA installed 550 metres of TufDuct across the site, delivering significant cost savings compared to traditional trenching methods while dramatically reducing disruption to existing rail operations.

The TufDuct system also performs better than traditional concrete alternatives. Our TufDuct 300 Series units provide three times more cable space (52,500mm²) than standard buried conduits, while the larger 430 Series units (114,750mm²) replace conventional cable pits entirely. Each lightweight unit (just 24-27kg) sits directly on railway ballast, with workers able to walk safely across the sealed lids during installation and maintenance.

Better for Everyone

TufDuct delivered practical benefits beyond cost and environmental gains. The lightweight units (just 24-27kg) install quickly without heavy machinery, making sites safer for workers. The system's durability matches traditional materials while offering superior longevity, and it reduced disruption to yard facilities by limiting excavation around existing tracks and minimised the need for rework when Stage 2 construction begins.

The system required rigorous testing before Australian rail authorities would approve it for permanent use. SEPA successfully proved TufDuct meets all safety and performance standards, demonstrating that sustainable solutions can exceed traditional requirements.

This pioneering work proves environmental innovation drives better outcomes: reduced costs, faster construction, improved safety, and massive environmental benefits. Sometimes the best solutions come from thinking differently about what others see as waste.