What measures need to be taken to optimise the Auckland rail network?

Auckland’s transport network is the most congested of any New Zealand city, with cars accounting for 67 percent of CBD travel and motorway trip lengths up 10 percent over the last four years.

The city’s rail network is also congested, comprising a mix of metro, passenger, and freight trains – some stopping frequently and puncturing the otherwise continuous flow of faster moving trains. With 28 level crossings, the network also interferes significantly with traffic flow.

Kiwi Rail and Auckland Transport are confronting these challenges with a business case that explores how rail investment can be optimised over a thirty-year horizon.

Chief Planning & Asset Development Officer, David Gordon, says the aim is not to compare rail with other modalities; rather to set out a pathway for governments who intend to use rail at the core of their rapid transit and decarbonisation objectives.

“Essentially, it is a way for us to identify inefficiencies in the network and discuss, at a political level, where capital needs to go,” he said ahead of the NZ Rail Conference.

So, what are the key takeaways from his research?

Segregation of different trains

With two tracks and three types of train on each, the first objective is to segregate the Auckland rail network to the greatest extent possible.

“This will allow nonstop trains to fulfil their intended function. They won’t be at the mercy of slower moving metro or passenger trains,” David said.

The key enablers of this segregation effort are widening the existing southern corridor with two additional tracks and a proposed cross town corridor around the Auckland Isthmus.

“Building this will allow freight to run outside the inner-city area and give metro trains 100 percent occupancy of the congested inner network.”

A secondary benefit of segregating freight is the heightened attractiveness it will give to freight rail. Over time, this could help minimise the need for articulated trucks, freeing up road space and improving the city’s emissions profile.

“Rail is inherently less carbon intensive than road, so a system that removes the need for articulated trucks is advantageous on that front alone.

“Add to that the improvements in congestion we will see from having fewer trucks on the road and you can see why it makes sense to make these provisions from freight rail. Trucks can take up five to six car slots and move painfully slowly around corners,” David said.

Segregation from the road network

With 28 level crossings, the Auckland rail corridor is highly permeable with significant congestion often seen near barriers. This breeds conflict between rail and road users and inflates the already lengthy commute times of motorists.

A long-term view of the network reveals the need for road closures and greater separations, David argued.

“This would have safety implications and free up traffic that would otherwise be sitting at lights for extended periods.”

New cross-town connectivity

Whilst a key benefit of the new cross-town corridor is freeing up the busy inner network, the new corridor is not only a freight route. Metro trains will also provide services and passengers will benefit from new East-West cross isthmus connectivity options.

No longer just a central spine, the new outer loop will create a more developed network enabling easier travel around the city, not just to/from its centre.

“The new corridor is key to increasing capacity, resilience and reliability right across the network” said David.

“It will create new travel options for Aucklanders and enable more people to go more places via fast, convenient, low-emission rail transport.”

Optimising existing capacity

Re-signalling parts of the network and extending platforms could allow trains to work closer together and add greater passenger volume onto the track.

David notes that, in the long-term, trains could increase in size from the current three or six carriages to up to nine cars.

“This would allow fifty percent more passengers to be carried on same train path,” he said.

However, such a move would also need to factor in the greater power requirements for large trains.

“Provisions will no doubt need to be made for this and, as work is undertaken on building new tracks, we would ensure that we future proof for longer trains.

“This will help to ensure that improvements planned now can be built upon as Auckland continues to grow.”

New rolling stock and depots

New or upgraded trains and infrastructure would allow for a speedier service, catering for greater passenger volumes and efficiency.

“More services mean more trains and places to stable and maintain them,” David said.

Improved stations and platforms

In a similar vein, station upgrades are important for enabling grater access to the network, as well as improvements to service. Both of these will help a mode shift to rail.

“These measures will be needed progressively as patronage increases on the network,” David added.

Improved maintenance and access regime

Defined access slots for Kiwi Rail throughout the year could enable continuous maintenance and vastly reduce the need for regular shutdowns, especially once the additional tracks needed for segregating traffic have been built.

“At any one stage you could isolate a small portion of the network and maintain normal service,” David said.

“Ultimately, if you don’t have a reliable and maintainable network, it is not possible to run reliable, frequent, and fast services so looking after what we have built, and what we will build, is fundamental.”

Further advice

While objectives may vary between rail networks, David says the underlying principle is the same.

“It’s all about setting out a clear vision of what is needed and not being knocked off your stride. You need to maintain a consistent view of what the network can or cannot do,” he said.

Talking more about the business case and what it means for Auckland, David Gordon will present at the upcoming New Zealand Rail Conference, hosted by Informa Connect.

This year’s event will be held 29-30 November 2023 at the Hilton Auckland.

Learn more and register your place here.

About David Gordon

David joined KiwiRail in 2007 and has held a variety of project, property, RMA and operational portfolios. His current role is overseeing KiwiRail’s strategic capital projects.