Rail Network Rebuild
Through the final stages of the Rail Network Rebuild (RNR) – beginning in December this year - we are delivering critical rail network upgrades before City Rail Link opens in 2026. These will support cuts in journey times, fewer delays and trains every 4-5 minutes at peak.
The rebuild replaces old foundations under tracks and upgrades drainage, allowing more reliable train journeys and helps prepare the network for City Rail Link.
The work involves removing the existing tracks and digging down up to a metre to replace the aging rock foundations under the tracks, replacing ballast and upgrading drainage to improve rail’s resilience to flooding.
The final stages of RNR complete our upgrade of the priority areas across the network, enabling an efficient rail network that can accommodate the increased level of services that comes with CRL.
Additional funding provided by the Government in the latest Budget ($159.2m) has allowed us to move forwards with certainty to plan and deliver much-needed upgrades on the rail network. These are essential to enable the faster, more frequent journeys that CRL and the other major projects we are delivering will bring.
We also received a further $48.8 million for upgrades to the Auckland network. These two funding pots are being wrapped into one delivery programme under RNR – to ensure the most effective, efficient delivery.
How the work will be delivered
The majority of the next and final stages of the Rail Network Rebuild will be delivered in extensions to the usual closures when all services are suspended during major holidays so our teams can safely work on the tracks and inside tunnels. This will include four weeks over Christmas 2024, and a couple of extended blocks around Easter 2025 and Christmas 2025 with some shorter periods of single line running. A full network closure may not be needed for all those blocks, but this is the maximum time needed. There is also some contingency allowed throughout the programme for unexpected events.
We know it’s vital to get the most out of this time period. That’s why we will be working 24-7 wherever possible. The hard work being achieved through Rail Network Rebuild is delivering a decade’s worth of work over 18 months - ultimately this will enable more efficient and faster train services. We thank commuters, passengers and freight customers for their patience with these disruptions as we safely deliver the huge amount of work.
This approach means relatively short sharp closures and less ongoing disruption when passengers and freight suppliers need the network most.
Keeping trains running
We are working hard with Auckland Transport to retain weekday peak services so Aucklanders can still rely on the train for their weekday routines. This means, wherever possible, outside major holiday periods, rail line closures will be at weekends or late evenings and have school holidays as planned contingency periods to support the programme being delivered on-time.
Our focus with AT, as we planned how to deliver this work, has been on working as effectively and efficiently as possible to reduce disruption to customers - we are trying to keep trains running for as many people and goods as possible, as often as we can, but sometimes we must close the network for safety and to get work done more quickly.
To find out more about public transport options during these works, customers can visit AT’s Journey Planner or to the AT Mobile app.
Customers can also view the train line status page on the AT website.
Find out where our teams are working and what we are doing here.
Without suspending frequent commuter services, it would be impossible to safely use much of this time-saving technology.
Rail Network Rebuild related documents proactively released under the Official Information Act.
KiwiRail Key Auckland Upgrade Projects
Current work: stage 4 - Papakura to Pukekohe
From 19 May to mid-January 2025, full upgrade and renewals works while the line remains closed for electrification. By delaying reopening the line to trains for a short time, major disruption at a later date is avoided.
Find out where we are currently working here.
Work will be carried out in phases with drainage upgrades until late July, followed by foundation replacements from August.
Night works
Much of this work needs to happen at night and on long weekends. Working at night gives our construction teams the longest possible window to work, getting more done in a shorter period.
Carrying out significant work like this on a 24/7 live network is extremely difficult. Although no commuter passenger trains are running between Papakura and Pukekohe, freight and long distance passenger trains still use this part of the rail network.
Because the project involves digging up tracks to replace foundations, working during the day would mean cancelling freight trains or working in shorter periods that are regularly interrupted – getting less done. This would extend the length of the project
by months and delay the return of passenger trains.
Our teams will be mindful of working near to residential properties and aim to get the job done as quickly and quietly as possible to minimise disruption.
Complete: Stage 3a Western Line and 3b Southern Line
Stage 3a: Major upgrades to the Western Line between New Lynn and Newmarket, including replacing aging foundations and upgrading drainage. Trains have returned to their normal frequency. Essential track work, including de-stressing rails, is being completed overnight during coming weeks.
Stage 3b: More minor track drainage-focused work on the Southern Line between Papakura and Puhinui, to improve resilience and the performance of the rail foundations in this low-lying part of the network. The RNR team will return to this part of the Southern Line to carry out foundation replacements when funding is approved.
What we are doing
The Rail Network Rebuild is challenging:
- Rail lines, sleepers and turnouts (which allow trains to switch between tracks) lifted away;
- Existing formation (compacted gravel that forms the base of the rail line) and ballast (the rocks the tracks sit on) dug out;
- New formation brought in and compacted to form a firm and resilient base;
- New ballast brought in and compacted
- New drainage to prevent future deterioration of the formation;
- The rails, sleepers and turnouts put back, aligned for safe and smooth train running.
This video shows how we replace the foundations under rail tracks.
Wherever possible we’ll also do proactive maintenance – such as replacing sleepers and trimming vegetation that would otherwise need to be dealt with in the coming years – and using the line closures to complete other rail related projects.
All railways require ongoing maintenance but we are thinking ahead and trying to avoid the need to come back and cause further disruption in the years ahead.
These photos illustrate some of the different types of work that go into the Rail Network Rebuild (RNR) .
Rail Network Rebuild work involves removing track and digging out the original formation (foundation), adding stabilizing mesh, putting in and compacting new formation, then replacing the rails and sleepers and then re-ballasting. This example at Sylvia Park includes adding a new crossover, which will improve flexibility on the network.
Using technology to get the job done quickly
To renew formation quickly, KiwiRail is using a range of specialist machines and technology. These include:
Panel lifter
The panel lifter can pick up and put down up to 75 metres of straight sections of track and sleepers at a time.
Stabiliser
Stabilisers shake and consolidate the track formation, to ensure new formation is stable.
Tamper
Tamper machines measure the track placement, lift it, and pack the ballast underneath to hold it in place. It helps create a smoother ride for passengers and freight.
Rail grinder
Rail grinders smooth irregularities in the tracks and restore their profile, so they last longer. It also helps to improve the ride for passenger and freight services.
