On this week's CarAdvice podcast, we spoke to the Director of Network Operations and Planning for the NSW Transport Management Centre, Craig Moran. You can find the audio at the bottom of this article.
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How do you monitor traffic flow?

We manage it through our traffic signal control system, which has detectors that are pieces of wire embedded into the road. They can measure the presence of vehicles, and the density and spacing of them.

We do have lots of cameras, in the thousands, around the road network in Sydney. They're largely used for concern when an incident has happened on the road, to confirm what the impact is.

Why do we sometimes get a bad run of red lights?

That can happen on occasion. Every set of traffic lights is trying to accommodate a range of movements - people driving on the main road or coming from the side streets, and of course pedestrians.

The traffic vehicle system is trying to balance all of those demands, and everybody is expecting a certain level of service, so we are trying to get the system to meet that service as best as possible.


What are the most difficult situations to manage?

It's when something unusual has happened on the road networks. Let's say there's an incident on one of our major motorways, and it gets closed, then we need to think about how do we manage that demand of traffic through the residual roads.

Quite often the system won't be able to respond fast enough, and that's when we manually intervene.

We see a lot of traffic lights out of sync these days. If we're concerned about emissions and traffic flow, surely things can be improved on technology?

The technology we have in Sydney was developed in NSW back in the '70s, and it's now quite advanced. It's used in 150 cities around the world.

The whole idea there is to try and get the best-coordinated traffic movement through the network or try and get as many green lights running together as we possibly can.

How many people are running these systems?

There are a few groups of people. We have a team of around ten people who are the brains of the system. They're the people that have done the mathematical equations and developed the software that makes the system work.

We have another group of about 20 people, who are located at the Transport Management Centre, and they're the operators that do the fine-tuning and adjust the system if there is a problem with its operation.

And then we have a couple of hundred people throughout the state who do the maintenance, who go out and fix things, because inevitably something breaks down, so we need them to fix it rapidly.

There are sensors in every traffic lane at every set of traffic lights. We know what the traffic is doing in every lane of the 4000 sets of traffic signals throughout NSW.


What's the biggest event you've had to manage?

The biggest one that I was personally involved in was the 2000 Sydney Olympics. It was a huge effort, and I think it was a huge success for Sydney.

How we managed the movement of people, and the operation of traffic signals, was key to moving people around Sydney at that time.

What creates the biggest problem that can set off the panic alarm?

When we get one of the major motorway tunnels closed due to a major incident, and there have been some instances where we've had some major accidents on the Sydney Harbour Bridge.

It's those big incidents that create those heart-stopping moments about how we're going to manage this and how we have as minimal impact on road users as possible.

Have you seen a noticeable increase in traffic volume and flow over the years you've been working there?

Traffic flow is increasing in Sydney, as they are in every capital city in Australia and throughout the world.

Think back 20 years, the peak period was probably between 7am, and 9am. That's now stretched to between 6am, and 10am, and it's different in various parts of Sydney.

But we're seeing peak periods extending in some of our major corridors, where we do have lots of traffic signals, like Parramatta Road and Victoria Road in Sydney.

The peak periods are also starting to extend into weekends. That's a straight reflection of population growth and nothing else.

The main difference is, that particularly Monday to Friday we do have other measures in place, like clearways. In some limited situations in Sydney, we have put some clear ways in on the weekend to deal with some of our major pinch points, and they're things we are constantly looking at.


What sort of planning is happening right now for the advent of autonomous cars?

The system that controls our traffic lights, SCATS (Sydney Coordinated Adaptive Traffic System), are already starting to plan for when vehicles become smarter. Such as the vehicle becomes the detector itself, rather than the piece of metal we have in the road (sensors), and how can we accommodate the automated vehicles.

We've also got a project underway where we're doing a trial with some trucks, where it allows the truck to talk to the traffic signal. In turn, it can extend a green light to let the truck through, because we all know trucks take longer to stop and are slower to get started.

If we can minimise the number of time trucks have to stop at traffic lights, then we can have a flow-on effect to other users and reduce the level of congestion on those corridors.