Engineering innovation to close our roads

In Auckland, an innovative trailer is quietly changing motorway safety, earning Auckland System Management (ASM) well-deserved accolades at the Transportation Group’s 2024 conference.

A practical answer to a serious problem

Managing road closures on Auckland’s motorway network is no small task. Every night, crews set up closures to create safe work zones, but breaches into these zones are dangerously frequent. Whether accidental due to confusion or inattention, or deliberate – the worst are those involving an attempt to evade police – the risks to workers are significant and potentially fatal. Traditional traffic management solutions like attenuator trucks and cones can be effective in some situations but haven't always been enough.

The Road Closure Trailer developed by ASM offers an innovative solution. Auckland’s motorways are managed under the ASM model, an alliance between Waka Kotahi NZ Transport Agency, HEB Construction and Fulton Hogan. The trailer provides a self-contained, easily deployable physical barrier to secure road closures. It’s towed into position, deployed in minutes by one person and forms a highly visible barricade that deters breaches.

From concept to reality

The idea for the trailer had been in the works for years. Initial designs involving complex telescoping structures and other technical hurdles prevented practical implementation. The breakthrough came when an airport gate system inspired a folding barrier design that could be mounted on a trailer. The result? A lightweight and durable aluminium gate system that unfolds to cover up to six lanes and the shoulder, with built-in solar-powered lights, batteries, remote monitoring and an anti-tamper alarm.

Critically, the system is simple enough for crews to use without specialised training or equipment: an impact driver is all that’s needed (to raise and lower the jockey wheel) and even that is optional. Weighing approximately 1.2 tonnes, a standard ute can tow it and deployment requires no heavy lifting or complicated setup – making it faster, safer and more efficient than traditional methods.

Proven success on the road

The true measure of the trailer’s success wasn’t winning the thoroughly deserved Matrix Innovation Award – that was just the icing on the cake. Rather, project leader Jim Bernhard was most fulfilled by the overwhelmingly positive user endorsements.

According to those in the field, the trailer has made a noticeable difference – and there’s proof: motorway cameras capturing Road Closure Trailer installations have shown vehicles approaching, hesitating and turning back, exactly as intended. Since its deployment, no vehicles have breached a closure where a trailer has been in place.

This success has prompted ASM to expand its fleet, with more trailers in production and potential for other roading managers across Aotearoa to add trailers to their fleets.

Celebrating innovation

The Matrix Innovation Award, presented at the Transportation Group’s annual conference, recognises outstanding advancements in transport safety, technology and engineering. Winning projects like the Road Closure Trailer demonstrate the power of using smart engineering to make a real impact.

Entries will open in late 2025 ahead of the Transportation Group 2026 Conference to be held in Wellington in March. The Transportation Group encourages anyone with a groundbreaking project to apply. Beyond the accolades, the conference awards celebrate ingenuity and progress – driving the future of transportation forward.

The Transportation Group is one of Engineering New Zealand’s Technical and Special Interest Groups. Over 1,100 Transportation Group members collaborate, network and learn to advance the knowledge, planning and management of transport in New Zealand.

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The Matrix Innovation Award is proudly sponsored by Matrix Traffic and Transport Data.