The right weigh

If you’re driving on one of New Zealand’s busy highways in the coming months, you may come across a sign you haven’t seen before – one that lets you know you’re approaching a Commercial Vehicle Safety Centre.

It’s the kind of thing most of us will never take the time to think about and, unless you’re a truck driver, you won’t need to. But behind the scenes, there is some impressive technology at play, and an excellent example of how technology can be used to improve the transport system.

Commercial Vehicle Safety Centres, or CVSCs, are basically weigh stations and are part of the New Zealand Transport Agency’s (NZTA) new Weigh Right programme, designed to reduce the number of overweight trucks on our roads.

Why is the overloading of heavy vehicles such a concern?

NZTA estimates that about 10% of trucks are carrying more weight than they are allowed to. 
On the one hand, that’s dangerous – from reduced brake performance, to tipping over – many things can go badly wrong for an overweight truck.

On the other, it’s unfair. Truck operators whose vehicles exceed the permitted weight aren’t paying their share in Road User Charges (RUC), to reflect the wear and tear they cause on the road. That means they’re able to undercut other companies that are doing the right thing, and gain a commercial advantage.

Under the current system, what usually happens is that at varying times of day an electronic sign instructs trucks to pull over at an upcoming weigh station. Police then spend between 10 and 40 minutes inspecting and weighing each of the trucks that have been pulled over.

As most of the trucks are following the rules, that makes for a lot of wasted time for truck operators, and lost productivity. Weigh Right reduces the number of unnecessary stops for truck operators by using technology to determine in advance which trucks are likely to be overweight – and therefore need to be tested – and which aren’t.

As trucks approach a CVSC, they pass over scales built into the road surface that measure the weight of the truck and its load. At the same time, an automatic number plate recognition camera captures the truck’s details and feeds them into the central system to determine the weight that the truck is allowed to carry.

The two pieces of data are checked against each other and, if it all points to the truck being overweight, the truck’s licence plate number is displayed on a roadside electronic sign further ahead, instructing the driver to stop at the CVSC. The weight of the truck is then officially measured on the weigh bridge.

When the CVSCs are unattended, the in-road scales and the cameras continue to gather data, to understand compliance and to allow follow-up with non-compliant operators.

On-Road Vehicle Compliance Programme Manager at NZTA, Dylan Hunt, says that the Weigh Right Programme is about improving road safety and increasing productivity.

“By using innovative new technology to decrease the number of unsafe, heavy vehicles on our roads, the Weigh Right Programme significantly contributes to the Road to Zero fatalities vision. It is improving the safety performance of vehicles, ensuring that businesses and other organisations treat road safety as a critical health and safety issue, and encourages safer choices and safer behaviour on our roads.”

So far, there is one CVSC in operation at Glasnevin in north Canterbury; another is due to be made operational this year at Paengaroa in the Bay of Plenty.

The programme will establish a total of 12 CSVCs on state highways around the country by the end of 2021. The sites are close to major centres, ports or highway junctions, and have been chosen because they are on routes that account for just under half of all freight travel in
New Zealand.

Dylan says that, by the end of this year, the plan is to expand the programme so that it can also check for compliance with heavy vehicle registrations, Certificates of Fitness and RUC.

Further ahead, the NZTA is looking at developing a range of second-tier CVSCs on less critical routes, which would be smaller and less frequently manned by Police.