The CRL will be a game changer, allowing more frequent trains and enabling the whole network’s capacity to double.
On day one it will increase the number of passengers who can travel into the CBD from 14,000 an hour to 27,000, with the potential for that to eventually hit 54,000.
That adds the equivalent of 16 lanes of traffic into the city centre at peak.
However, the CRL will only deliver these benefits if the rest of the network is transformed so it can keep pace.
The programme goes far beyond the usual maintenance we carry out over summer.
Work of this scale, which essentially involves removing and replacing a rail line, requires significant planning, design and scheduling.
We have already been replacing worn rail and sleepers, and now we’re tackling the foundations under sections of the tracks where it is too weak. We will be digging out and rebuilding the formation (a layer of compacted rock underneath the tracks) and replacing the ballast (the stones that the rail and sleepers rest on).
By the time it wraps up, we will have renewed 18.5km of rail, 50km of sleepers, 26km of formation, 59.6km of ballast, and improved the drainage for 48.4km of track.
That programme is the equivalent of building 26km of new railway, and we’re going to do it inside an operational network.
Alongside other upgrade works - such as constructing a third main line and electrifying the network from Papakura to Pukekohe - the project represents a significant investment in Auckland’s future.
There have been a number of rail improvement projects in Auckland over the past few decades - such as double tracking the Western Line, construction of the Onehunga and Manukau Lines, station rebuilds, new signalling, electrifying the network and new trains. Some sections of track have already been rebuilt from the formation up and we don’t need to touch those.
However, carrying on at the pace we have been on to date is not an option.
Without this work, the current commuter timetables – much less the expanded services the CRL will make possible – will become unsustainable as more temporary speed restrictions need to be put in place to maintain safety, meaning longer journey times.
Once the CRL opens, there will be more frequent trains and fewer time slots available for ongoing routine maintenance.
The Rail Network Rebuild will raise the base standard of the network and concurrently we’re adopting new maintenance practices, which will allow that standard to be maintained in the shorter access windows.
Without being at this base standard in time for CRL, routine maintenance would not be able to keep pace with wear and tear, resulting in network performance deteriorating.
If KiwiRail was to undertake the work in its existing maintenance windows – evenings, weekends and holiday periods – the Rail Network Rebuild could take until 2041 to complete.
After considering the options, a staged approach was chosen.
Shutting down sections as they are worked on still allows the rest of the network to continue to operate, while still allowing most of the work to be finished before the CRL opens.
The approach we have taken is in line with what is done overseas. As an example, a stretch of Melbourne’s Upfield line was shut to commuters for three months as part of a major project in 2020.
People have asked why we cannot close one track at a time, keeping the other open and the commuter services running. Doing that would stretch out the timeline for the project and would not deliver what is needed to take advantage of the CRL going live.
It is also not a safe solution. The equipment we use cannot operate safely around 25,000 volt overhead electrical lines used to power the commuter units while they are live.
On top of that, the space available on the ground would be too narrow and restricted to allow machinery to operate safely alongside people, with trains whizzing by.
The tight space is also the reason why another suggestion – to use bigger machines, and many more workers – is not an option.
We are already planning to use technological innovations to improve productivity.
These include lifting and slewing the overhead power lines, allowing us to use larger machines to dig out the existing formation. Using panel lifters allows us to remove and reinstate track faster, meaning more time to work on what is under the track. Large stabilisers and tampers will ensure the track, as a whole, will provide the best ride possible for Auckland’s commuters.
More than 130 people will be working on the Rail Network Rebuild - consisting of about 60 per cent KiwiRail staff and 40 per cent civil and specialist contractors.
KiwiRail has doubled the number of its track teams in Auckland and has secured additional plant and staff from around the country to support them.
It’s going to be a huge effort and we acknowledge that it will be disruptive.
However, we’re working hard to make sure we are able, over time, to deliver a rail network that provides a reliable, more-frequent, lower-emission transport solution for Auckland.
- David Gordon is the Chief Operating Officer - Capital Projects and Asset Development, for KiwiRail.
