Regional Economic Development Minister Shane Jones marks the announcement of funding for the North Auckland Line
The New Zealand government’s decision to invest $94.8 million to improve the rail line between Swanson and Whangarei in Northland underlines the clear vision it has for rail in New Zealand.
Announcing the funding in September, Regional Economic Development Minister Shane Jones described rail as a crucial part of building a modern transport system, connecting people and regions, efficiently moving freight around the country and helping to take trucks off the roads.
However, he added, rail has been left to languish over the decades, receiving only a fraction of the investment needed to deliver an efficient and reliable network.
The North Auckland Line is a prime example of that. It is worn and prone to flooding, and the infrastructure will fall apart in the near future without proper maintenance. As a result, there are speed restrictions on many parts of the line, so trains have to travel slowly, and freight services are too easily stopped by weather events and derailments.
Tunnel 2, the one closest to Helensville, has already had steel ribs installed to ensure it stays safe in the short term. Without this work the North Auckland Line would have had to be closed within one or two years.
A long history
Rail has a long history in Northland. What became the North Auckland Line was built in sections from the 1870s, with the link between Helensville and Whangarei being built progressively between the 1880s and 1920s. The line north of Kauri (north of Whangarei) to Otiria (near Kawakawa) and the Dargaville branch line are currently mothballed.
The line now running between Swanson and Whangarei is approximately 181 km long and includes 13 tunnels, 88 bridges and 950 culverts. Used predominantly to transport freight, trains have carried logs and woodchips, china clay, dairy products, coal, cement, limestone, fertiliser, livestock, and general freight. Commuter services have never proved sustainable in the long term, and now run only between Auckland and Swanson.
In 2000 almost a million tonnes of freight a year was transported in the region by rail, marking the highest point of its popularity. With the move of Whangarei Port to Marsden Point in 2007, however, this dropped away significantly, and had fallen to 300,000 tonnes by 2008.
Other factors affecting usage include the poor condition of the rail line, resulting in slower trains and delays. Now, only 116,000 tonnes of freight is currently carried on the North Auckland Line a year.
KiwiRail runs one freight service to and from Whangarei each week day, carrying processed dairy products from Fonterra’s Kauri plant to MetroPort and on to Port of Tauranga; a small volume of high-value china clay between Whangarei and Metro- Port; and woodchip from Whangarei to Kawerau.
However, even this reduced tonnage is still equivalent to more than 8000 truck trips avoided each year. This means that if the line closed, Northland would see increased congestion, higher road maintenance costs, and higher transport emissions.
The investment announced by Minister Jones will allow us to offer more reliable and timely freight services and work to grow freight volumes, which will give Northland businesses/exporters more options to move their produce, and help take more trucks off the road.
Planned improvements
While this work is about maintaining what is already there, we are also looking at improvements to the line. Principal among them is lowering the existing tunnels so that hi-cube containers – which are an industry standard for export goods – can be carried on the line.
As part of the strengthening work on the tunnels, KiwiRail will be investigating what would be needed to lower the tunnels (to take hi-cube containers) in preparation for this work to be done later. For most of the tunnels, the works are expected to be relatively straightforward, but lowering Tunnel 2, which has been a problem almost from the day it opened, presents some challenging engineering problems to resolve.
The Ministry of Transport has completed the North Auckland Line Business Case for rail in Northland, and an Upper North Island Supply Chain Strategy study is underway which will focus on the respective roles, opportunities and options for Northport, Ports of Auckland and Port of Tauranga. An improved and extended North Auckland Line and Marsden Spur could play a key role in that, opening the way for freight to flow to and from Northport by rail.
KiwiRail has held a designation for a 20 km Marsden Point rail spur for several years, and we have investigated the design and potential construction methods for the link, as well as costs and timeframes. However, the government is yet to make a decision on a rail line to the port.
The entrance to Tunnel 2, the Makarau tunnel, north of Helensville – the tunnel is one of the longest on the North Auckland Line
Reinforcing ribs inside Tunnel 2 now support the tunnel lining – KiwiRail has nearly completed the work to strengthen Tunnel 2
Detailed works
The work KiwiRail has currently been funded to undertake on the North Auckland Line includes the following.
Track, sleepers and ballast ($40–$50 million)
Works will target improving track resilience and reducing wear on track and rolling stock. Approximately 30% (54 km) of the network will be either upgraded or replaced, particularly worn areas where there are bends, turnouts and steep grades. This equates to around 80 linear kilometres of new rail. Approximately 80,000 sleepers are expected to be replaced and 50,000 cu m of ballast added.
Replacing five of the 88 bridges on the line ($15–$20 million)
These mostly wooden bridges will be replaced with concrete structures due to their deteriorating structural condition.
Repairs to 13 tunnels ($7–$10 million)
KiwiRail has nearly completed the work to strengthen Tunnel 2, north of Helensville, one of the longest on the North Auckland Line. This has included installing steel ribs to support the tunnel lining in an area of deformation. Work will also be done on the other 12 tunnels, including plaster repairs, crack filling and drainage improvements.
As part of the maintenance work on all the tunnels, below-ground conditions will be investigated in preparation for later work to lower the ground level in the tunnels (to fit the larger, modern hi-cube shipping containers).
Clearing drains and culverts ($7–$10 million)
Trackside drains along the 181 km stretch of line will need to be cleared. A quarter (237) of the 950 culverts (drainage pipes) on the line are in poor condition and will be remediated as required. Maintaining the drains and culverts is crucial for ensuring the stability of the rail line and managing flood waters during weather events. Many have not been looked at for decades.
Culvert and drainage work will protect the track condition, reducing clay and mud build-up in the track ballast, which makes the track more susceptible to movement.
Work stabilising the slopes on nine embankments ($3–$5 million)
This work will include drainage improvements and widening the embankments. There will be ongoing monitoring of the embankments to determine if further civil engineering work is required over the longer term.
Vegetation control along the rail line ($1 million)
In recent years, vegetation clearance has been limited to removing fallen trees and branches from the track. A significant amount of vegetation needs to be cleared from the sides of the track, which will protect the track and rolling stock, as well as improving access to worksites.
Review and make improvements to the Whangarei Rail Yard ($2–$3 million)
Changes will be made to improve safety and make freight handling and storage more efficient. For example, disused track that used to go to Whangarei Port could be removed.
A huge project
We are excited by the changes this will bring to our abilities to offer Northland businesses a better deal. We will be able to lift some of the speed restrictions, reducing the rail freight journey time to Auckland by approximately 1.5 hours. And we will be able to make rail services more resilient and reliable, reducing the number of line outages.
Where possible, KiwiRail will be using Northland-based contractors and sourcing materials from Northland. This will see millions of dollars going into Northland’s economy and help boost the region. If KiwiRail takes on any more permanent staff, we will look to Northland first.
This huge project will be structured into a mix of larger and smaller jobs making up the overall programme of works, and we have taken steps to ensure the local industry is aware of the opportunities, not just for large companies, but also for smallerscale contractors. Recently, in Whangarei, we held a briefing for about 40 contractors about future work opportunities. We have ensured that where possible the work is broken into bite-sized pieces suitable for smaller contractors.
We are delighted that the work is already underway, with the majority of it targeted for completion by September 2020. The investment is the first step in setting up the line to deliver for KiwiRail, for the region and for the country.
David Gordon is KiwiRail’s chief operating officer – capital projects and asset development; he oversees KiwiRail’s strategic capital projects and leads KiwiRail’s collaboration with the government, its agencies and local government on transport policy and investment issues