Article written by Matthew Stuart – Service Leader – Rail Engineering

The Lower North Island Integrated Mobility Project (LNIRIM) is a major investment programme aimed at improving freight and passenger rail performance, safety, and operational resilience across the lower North Island. The Yards Package forms a critical component of the programme, supporting the introduction of the new fleet of Tuhono Battery Electrical Multiple Units (BEMUs) to allow for increased stabling capacity, charging, maintenance, and futureproofing of rail yard infrastructure.

Vitruvius and Beca are engaged to support the planning, design development, and technical assurance of the Masterton and Palmerston Noth rail yards within the LNIRIM programme. Working with several major stakeholders, including, KiwiRail, Greater Wellington Regional Council, Masterton District Council, Palmerston North District Council, Alstom and Transdev to name a few.

The purpose of our engagement is to provide specialist rail and civil engineering design expertise and provide solutions to complex upgrades of existing rail yards requiring coordinated multidiscipline design. The project involves interfaces with third party landowners, a new maintenance depot D&C Contractor, council assets, GWRC leased land and integration with an existing freight yard and signalling upgrades.

Through the optioneering and detailed design stages, we are tasked with ensuring solutions are:

• Operationally robust
• Compliant with KiwiRail standards
• Practical to construct and stage
• Aligned with programme budget and delivery constraints.

Our exceptional team are delivering the track, civil and geotechnical design, integrated with signal designs and working with our stakeholders to ensure seamless integration with all design, delivery, maintenance and operational requirements. We are excited to work with Beca to showcase excellence in the digital delivery space and ensure this complex multidiscipline design is integrated into one federated model accessible to all stakeholders.

Our team of specialists bring a depth of experience working in live rail yards and other complex operational environments, combined with a strong, practical understanding of KiwiRail standards and assurance processes. Our integrated approach, bringing together civil, track, and constructability considerations, enables us to develop solutions that are not only technically robust, but practical to deliver. This, together with our pragmatic, solutions focused mindset, meant we are well placed to support the yards package and add value throughout the design and delivery process.

The LNIRIM yards package reflects Vitruvius’ role as a trusted rail partner, adding value through integrated design, early risk management, and solutions that support network performance, safety, and long term resilience of the Wellington Metro.

Article written by Simon Cave – Sector Lead – Rail and Senior Principal – Project Management

The Ferry Replacement Programme (FRP) is one of New Zealand’s most significant transport infrastructure initiatives, supporting the introduction of a new fleet of interisland ferries and the long-term resilience of the national freight and passenger network. The Programme comprises several major stakeholders including Ferry Holdings Limited, Centreport, Port Marlborough and KiwiRail/Interislander. The KiwiRail led elements of the programme involves complex upgrades to rail yards, port interfaces, and associated infrastructure in Wellington and Picton to ensure seamless integration with new ferry assets while maintaining continuous interisland operations.

Vitruvius is proud to be playing a key role in FRP, providing specialist rail engineering, track and civil design, digital engineering, and project controls expertise to KiwiRail. Our team is embedded within the programme delivery environment, supporting the planning, design, staging, and assurance of critical rail infrastructure works at each terminals and adjoining networks, all with the target of bringing the new ferries into service in 2029.

Drawing on our experience delivering complex, operationally constrained rail projects across New Zealand, Vitruvius brings a strong focus on constructability, interface management, and safety in design. Our involvement spans early optioneering through to detailed and IFC design, helping KiwiRail manage risk, maintain operations, and prepare the network for future demands.

The Ferry Replacement Programme reflects Vitruvius’ commitment to delivering technically excellent, collaborative solutions on nationally significant infrastructure projects.

Article written by: Nigel Holman – Service Leader Road Engineering

Vitruvius is proud to be supporting the delivery of the Putauaki Kawerau Container Terminal (PKCT). This is a landmark infrastructure project that will establish a new rail freight hub for the Eastern Bay of Plenty and unlock long‑term economic benefits for the region.

We are currently assisting PKCT by overseeing construction supervision and providing surveying set-out services for a complex and tightly scheduled build. Our role spans end‑to‑end engineering and planning services, including rail design, stormwater assessment, traffic impact assessment, civil and roading design, integrated stormwater management, and working closely with Engeo to undertake the specialist geotechnical investigations and design.

Supported by the Provincial Growth Fund, this initiative represents over five years of planning and serves as a pivotal driver for enhancing regional supply chains and supporting local industry within the Eastern Bay of Plenty.

Once operational, PKCT is expected to remove up to approximately 18,000 heavy truck movements from surrounding roads each year, reducing congestion, improving safety, and delivering meaningful reductions in CO₂ emissions.

The project is now well into its construction phase. Over the Christmas break, Vitruvius worked closely with the Contractor and the Principal to deliver the important first stage of the programme, setting the project up for a strong start. Taking advantage of the Christmas block of line, we reinstated more than 200 metres of existing track.

As the project progresses toward its planned opening in mid‑2026, our team will continue working alongside the contractor and PKCT to deliver:

• a new 750 metre long loading platform
• approximately 1.2 kilometres of new heavy duty rail track
• more than one hectare of new container storage area
• around 100,000 cubic metres of earthworks and imported fill
• new stormwater storage and road access infrastructure.

The PKCT project reflects Vitruvius’ broader capability to deliver complex infrastructure projects that will make a real difference to the region and local community. We are proud of the progress achieved to date and look forward to continuing our contribution as this important project reaches its next milestones.

Tunnel 21, which is located between Kaikoura and Blenheim on KiwiRail’s Main North Line, had to be upgraded to achieve minimum clearance standards, improve line speed and importantly, increase the overall network resilience of the line following the North Canterbury Transport Infrastructure Recovery (NCTIR) project. 

Vitruvius was brought into the project based on our expertise in spatial survey and design, road design, rail geometric design and digital engineering. We surveyed the track alignment and inside of the tunnel using laser scanning technology to produce a 3D model for the track design. Using KiwiRail rolling stock data, a full spatial assessment of the tunnel was completed based on the types of rail vehicles in use on the main north line. 

Following that survey work, a thorough optioneering exercise was undertaken in partnership with KiwiRail and other specialist consultants, to explore how we would make the tunnel more resilient and improve the line speed with an efficient and effective solution. The preferred solution, which has now been delivered, involved a new offline rail alignment through a 500,000m³ cutting, and a new road over rail crossing structure. The state highway also required an online re-alignment to accommodate the works. 

This project was complex due to a number of factors: the state highway crosses over the railway lines; geometry; safety and cost for scale of earth and structural works; environmental considerations of sensitive wetlands; and private access routes.

We managed the digital model and interface to provide information from the contractor through BIM delivery.

Article written by Selwyn Blackmore – Business Leader and Sector Lead – Transport, and Graeme Corin – Senior Transport Engineer

Vitruvius was engaged by KiwiRail to support the reopening of the Dublin Street/Auckland Street intersection and the adjacent road and rail level crossing in Picton. The intersection and crossing had been closed for over 12 months to accommodate access changes associated with the former IREX project. Following the Government’s decision to discontinue IREX, the reinstatement of this key connection was prioritised and has since been completed.

Vitruvius delivered an end‑to‑end design and delivery support package for KiwiRail to enable the reopening. Our role included leading the detailed road and rail design, civil design inputs, project management, construction supervision, and contract administration to NZS 3910. The project also involved close coordination with Marlborough District Council, Marlborough Roads, and NZTA to ensure the works were delivered efficiently and safely.

The reopening resolved a prolonged disruption to traffic movements and reinstated an important road and rail interface following an extended period of closure.

Article written by Henry Watson – Senior Rail Project Engineer

Vitruvius is proud to have supported Auckland Transport (AT) in delivering the Wiri Depot upgrade project which went into use in November 2024.

The 550m depot is the main maintenance and stabling facility for Auckland Transports new Electric Multiple Units (EMUs) trains. The project features 10 brand-new stabling roads built by John Holland between October 2023 – November 2024, where Neil Mason acted as the Engineer to Contract, with Henry Watson managing the day-to-day as the Engineer’s Representative.

The entire depot was built up from scratch, covering a number of disciplines containing earthworks, drainage, track, Overhead Line Equipment (OLE), lighting, signalling, Communications, Signalling and Rail systems (CSR), Electrical and Bulding services (E&B).

The depot is a crucial part of infrastructure for AT, serving as the hub for the new fleet for the City Rail Link (CRL). Each train visits the depot at least once a month for maintenance, undergoing minor inspections every 1,000 kilometres. As mileage increases, the inspections become progressively more comprehensive, ensuring the fleet remains in peak condition.

Wiri also marked the starting point of the Third Main Line, with a section of the new line completed in 2025 as part of a staged delivery programme. The additional track allows freight trains to operate independently of commuter services, reducing congestion and improving network efficiency.

It was an incredible project to be a part of, being able to watch the depot being built from the ground up.

Article written by Simon Cave – Sector Lead – Rail & Senior Principal – Project Management

KiwiRail engaged Vitruvius to lead the Digital Integration workstream for its European Train Control System (ETCS) Level 2 Programme in Wellington. This programme represents New Zealand’s first ETCS Level 2 installation and is a major step forward for the Wellington metro network, enabling increased service capacity through the removal of lineside signals and reduced train headways.

Vitruvius was appointed based on several key strengths, including our established working relationship with KiwiRail’s Digital Engineering team and deep understanding of their digital requirements, our long‑standing knowledge of the Wellington metro area developed through more than 15 years of work in the region, and our collaborative, relationship‑based delivery model. This approach ensures close integration with client teams and supports the detailed design of complex rail features such as turnouts and points of switch (POS), track alignment changes, level crossings, platforms and axle counters.

The ETCS Level 2 Programme spans the entire Wellington Electrified Area (WEA), covering approximately 105 kilometres of rail corridor. Vitruvius’ involvement has focused on early‑stage digital integration to de‑risk design, cost estimation and construction by developing a comprehensive digital twin of the network. This work has been critical in preparing the programme for downstream delivery as procurement and system design activities progress.

The ETCS system requires the installation of extensive lineside infrastructure across the network, including new Combined Services Route (CSR) ducting, balises, cabling and radio network upgrades to support GSM‑R communications. Delivering these works requires access to almost every part of the rail corridor. Establishing a detailed, accurate digital representation of KiwiRail’s existing infrastructure has enabled early identification and mitigation of key risks, clearer definition of scope, and greater certainty ahead of construction.

A core requirement of ETCS Level 2 is a precise understanding of the location and configuration of critical rail assets. Vitruvius’ digital integration work has focused on capturing, validating and digitising this information so it can be reliably used by the ETCS system supplier during detailed design.

The digital twin programme commenced with the establishment of a master survey control network across the WEA, followed by targeted surveying to fill gaps where point cloud data was not previously available. With full corridor coverage achieved, the focus has shifted to extracting key model features and associated asset data to support both the ETCS programme and broader network needs.

Beyond ETCS, the value of this digital dataset for long‑term asset management is significant. The work undertaken through this programme has created a strong digital foundation for future planning, maintenance and operational decision‑making across the Wellington metro network.

Article written by Albert Ho – Service Leader – Civil & Water Engineering

The Lillington Emergency Response project for Auckland Council, Healthy Waters puts Vitruvius on the map of the Auckland Water sector. The high priority project, with stakeholders reaching as high as the Auckland Mayor, was entrusted to us based on our relationship with KiwiRail, engineering expertise and commitment to respond. The project addresses the risk of disruption to Auckland’s busiest train line, as a result of a stormwater pipe collapse.

This project showcases Vitruvius’ ability to pull Healthy Waters and KiwiRail together in a rapid, collaborative response to cross sector/discipline risk.  Overall, Vitruvius facilitated contributions from three major public infrastructure organisations, including NZTA Waka Kotahi, and multiple contractor entities, towards a swift and pragmatic solution in mitigating the risks presented in this high-profile project.

A 400mm brick culvert, built in 1946 and spanning 20m, lies beneath the Auckland Rail Network Southern Line and shoulder of the SH1 Southern Motorway, about 500m north of the Greenlane roundabout. The brick pipe asset was deformed, and likely the cause of rail ballast soft spots and sleeper movement directly above. Risk of pipe collapse was mitigated with slip-lining of the old brick asset with a 225mm uPVC pipe, secured with grouting to reinstate the structural integrity of the asset.

The final project outcome is a de-risked stormwater asset that functions as designed, with its lifecycle increased by an additional 50+ years, and the above rail network operating at its full capacity without limitations. The project was completed with praise from the highest level at Healthy Waters. This milestone project showcases Vitruvius’ ability to bridge disciplines and sectors, demonstrating our commitment to Auckland’s critical infrastructure, and further strengthens the relationship with our strategic key clients.

KiwiRail initiated the Rail Network Rebuild (RNR) programme to prepare the rail network for increased service frequency and operational demand associated with the opening of the City Rail Link (CRL).

Vitruvius provided strategic advisory support during the early development of RNR, led by senior principals including Neil Mason and Terry Hodder. This work focused on establishing a robust framework to support network readiness and resilience under constrained access conditions.

The RNR involvement initially commenced under field engineering and asset management support, which subsequently transitioned into targeted technical delivery roles. This led to Vitruvius undertaking discrete rail infrastructure design packages, including:

• Drainage design for operational rail corridors
• Track design within constrained brownfield environments
• Complex turnout design, including works at Quay Park

Through this evolution, Vitruvius supported KiwiRail in addressing specific network constraints and asset upgrade requirements, contributing to improved network performance and constructability outcomes ahead of CRL commissioning.

Supporting one of KiwiRail and Greater Wellington Regional Council’s critical and high risk renewal projects in delivery and design.

Vitruvius supported KiwiRail’s Wellington Metro Upgrade Programme (WMUP) management team by delivering a range of critical roles across the WMUP III Wairarapa Tunnels Renewals Project. What commenced as drainage design, delivery support and MSQA services, led by Matt Stuart, evolved as the project progressed to include Engineer’s Representative services for the drainage contract, Project Director leadership provided by Neil Mason, and additional project engineering and project management support to enable successful delivery of the works within a complex operational environment.

The Remutaka Tunnel (renamed from Rimutaka in 2017), is an 8.8km single bore Railway tunnel constructed from 1951 to 1954 and opened in November 1955, replacing the Rimutaka Incline railway that had made its way over the Remutaka Hills since 1878 (now known as the Rail Trail to local hikers and bikers). The tunnel runs through New Zealand’s Remutaka Range and is the second longest railway tunnel in the country. The location of this tunnel and the regular use for freight and passenger services makes maintenance periods difficult to come by.

The majority of the components within this tunnel have not been replaced since the track was first constructed in the 1950s and the windows for renewals are particularly short given the amount of drainage and track that is to be renewed throughout, requiring an innovative and collaborative approach to construction. The hard deadlines for construction require designers, contractors, project managers, programmers, construction managers and commercial teams to work closely together to provide a proactive and safe plan of attack. The success of this project will come down to each stakeholder feeling a part of the team and buying into the project goals.

Drainage Design and Delivery

Designing a drainage system in a tunnel environment that is able to be safely removed, recycled at the next renewal and takes into account productivity/available track time is no easy feat. Vitruvius led the drainage design for both tunnels, responding to a number of complex principal requirements. A key consideration was designing a system capable of withstanding loads from track panel lifters used during track relay works through the tunnels. The solution also had to convey an unknown flow rate through the short circa 650m Maoribank and the significantly longer circa 8.8km Remutaka tunnel. Following initial site investigations, remote flow rate monitoring was installed to aid in the design of the drainage system and water samples were collected to test for the presence of contaminants and iron.

An initial concept design was produced for the internal tunnel drainage only with a number of recommendations to the client to ensure a whole system approach to upgrading the drainage had been considered. In order to progress to detailed design, Vitruvius requested further surveys be undertaken of the external tunnel drainage to identify the asset condition, location and outfalls. This meant a full system design could be provided to prevent downstream defects causing an overflow of the tunnel drainage.

The detailed design offered two solutions for differing scenarios within the tunnel, the more complex of the two for higher flow rates comprised of a Megaflo system throughout the tunnel with a layer of drainage metal, a filter layer of sand and geofabric working in unison to increase the design life of the solution and a walkway that provided adequate underfoot conditions for maintenance. For increased efficiency within the tunnel a second option for lower flow rates was also proposed that allowed for the removal of the Megaflo and sand from areas of the tunnel where the flow rate was considered lower than 0.2l per s.

The design underwent review, during which the construction team requested amendments to enable faster installation within the available work windows. Rapid turnaround of design reviews and approvals allowed these changes to be incorporated efficiently, resulting in a solution that was well‑suited to the tunnel environment and could be installed by the contractor within the permitted timeframes. The value of having a strong design manager and early contractor involvement, working collaboratively with the client, was clearly demonstrated in the lead‑up to site commencement.

Civil and Laydowns

On short notice, Vitruvius was engaged to act as Principal’s Project Manager and Engineer’s Representative for the newly awarded NZS 3915 contract to construct three laydown areas as part of the enabling works. With commencement deadlines looming and several critical risks unresolved, a proactive and collaborative approach was required to mitigate potential impacts to programme.

Through coordinated stakeholder engagement, legal and planning reviews, and the development of strong working relationships across multiple risk areas, these risks were effectively managed. This enabled the critical laydown works to commence and be completed without disruption to the project’s critical path drainage works. Vitruvius is proud to have supported the project team in navigating these challenges and delivering outcomes aligned to a shared project goal.

Project Director

Neil Mason, who was Managing Director of Vitruvius at the time, stepped in as Project Director for the Wairarapa Tunnels 1 and 2 delivery to support best practice long tunnel project delivery. Having worked on all of Aotearoa New Zealand’s long rail tunnels in some capacity, Neil brought a wealth of experience in the safe and practical delivery of complex tunnel projects. This depth of experience supported the WMUP team in delivering the programme of works within a highly complex safety and stakeholder environment – the kind of complexity Vitruvius thrives in.

Vitruvius initially began on the project in February 2023 with support and advisory requirements increasing over time. We were grateful to have joined our valued client on this project delivery journey and bring not just our rail knowledge, but our project delivery expertise as well in support of their project goals to safely deliver these critical works to programme. So far so good!

Vitruvius would like to acknowledge all of the fantastic people that are involved in delivering this project and their companies – Our Client and Partner KiwiRail, consultants Tonkin & Taylor, WSP and Aurecon, Track and Drainage construction – Titan Contracting Group, Civil and Laydowns – Mills Albert, Tunnel Ventilation – BEST Engineering, and the vast network of sub-contractors and suppliers that make a project of this scale a success.