Australian-first StormFLO® trial at North East Link

Demonstrating the suitability of an HDPE twin wall sustainable engineered solution with the inclusion of recycled material, installed under a road pavement in a government infrastructure project.

Project background

North East Link (NEL) is Victoria’s largest road investment and part of the state’s ‘Big Build’ project, addressing crucial gaps in Greater Melbourne’s transport network. The project is designed to connect the Metropolitan Ring Road (M80) and Eastern Freeway (M3) and includes upgrades to the Eastern Freeway, as well as the construction of twin 6.5km tunnels between Watsonia and Bulleen, and new interchanges.

Spark, a multinational consortium, secured the North East Link Primary Package PPP, valued at $11.1 billion.

The challenge

Vinidex partnered with Spark to implement the first trial in Australia of StormFLO® – a PE twin wall drainage system incorporating recycled material, and installed under a trafficable road pavement, aiming to demonstrate the suitability of a sustainable engineered solution for the Department of Transport and Planning (DTP) road network.

Endorsed by NTRO, Ecologiq and PIPA as an Australian-first, StormFLO® is the only Australian‐manufactured twin wall plastic pipe containing post‐consumer recycled (PCR) content certified to AS/NZS 5065¹ and meeting the UCLS testing requirements in PIPA’s Technical Guideline POP208 – Specification and testing guidelines for recycled materials suitable for non‐pressure plastic pipe applications.

Successful completion of this test could lead to approval for DTP assets in future infrastructure projects.

The solution

StormFLO® by Vinidex is a twin-wall corrugated HDPE pipe, specifically designed to incorporate recycled content and engineered to meet the requirements of AS/NZS 5065 and POP208, ensuring a 100-year design life.

Testing involved the installation of StormFLO in a road pavement crossing, on a high volume and heavy load temporary site access road and assessing the performance of the flexible plastic pipes at regular intervals during the trial period. Vinidex was present at the critical part of the installation, providing additional CCTV monitoring during and after the construction of the temporary road.

The trial was regarded as a great success – from StormFLO’s ease of installation, requiring less mechanical movement than traditional options, to the excellent overall performance of the pipe recorded at each inspection.

The 12-month CCTV and laser profile review showed StormFLO performed exactly as predicted and recorded little deflection, measuring only a stable 2.1% deflection of a maximum 5.5% allowable deflection of the mean internal diameter of 363mm.^2,3

The trial demonstrated that a twin-wall pipe containing external recyclate, when manufactured to the Australian Standards, and used in the right application, is a smart and sustainable solution for under-road pavement applications.

1. AS/NZS 5065 – Australian / New Zealand Standard – Polyethylene and polypropylene pipes and fittings for drainage and sewerage applications.

2. The allowable deflection for plastic pipe must not exceed 5.5% of the original diameter as per the requirements of WSA 05-2020 conduit inspection reporting code of Australia.

3. With a manufacturing allowable tolerance of +/- 3mm range of 360mm–366mm.