Published reports to date include:
Before beginning detailed work on the Avondale–Southdown Project, KiwiRail conducted a high-level analysis of the proposed route and transport mode, using a framework aligned with NZ Transport Agency guidelines. This early screening step was designed to inform current workstreams and support the development of a future business case.
In parallel, the team has been hosting local community leaders and stakeholders on tours of the Avondale–Southdown rail corridor. These tours aim to build understanding of the potential line, its benefits, and the process we're following to advance the project.
During these engagements, a small number of individuals asked whether the existing designation remains the best route, whether heavy rail is the most suitable mode and what other options have been thought about.
This report outlines the analysis process, presents the results, and demonstrates that alternatives have been properly considered.
The results in short: the analysis found heavy rail as the preferred mode, and the existing designation as the preferred route – as they deliver the strongest overall benefits across multiple criteria.
Read the full report: Avondale–Southdown: Multi Criteria Analysis Assessment Report
KiwiRail commissioned engineering consulting firm WSP to undertake a dedicated study of network resilience. It was created to understand the operational benefits right across the isthmus that this strategic link could deliver, under both normal and degraded conditions of the Auckland metro rail network. This workstream forms part of KiwiRail’s broader programme to protect the existing Avondale-Southdown designation and develop a robust case for future investment.
The study focuses on the corridor’s potential to improve network resiliency, capacity, and flexibility, particularly in the context of Auckland’s growing metro, freight, and interregional rail demands.
The report evaluates how AS could enhance service reliability, support higher train frequencies, and provide alternative routing options during planned maintenance or unplanned disruptions. It outlines the methodology applied, key assumptions, and the results of technical assessments, including capacity modelling and scenario testing.
Most importantly, it demonstrates the extent to which AS strengthens Auckland’s rail network performance and underpins long term transport objectives.
The results in short: The incorporation of the Avondale-Southdown rail corridor to Auckland’s isthmus rail network would unlock up to 32% extra capacity on the inner network – an increase that could otherwise only be achieved via substantial investment in widening those inner network corridors. It would improve network reliability (which will otherwise come under pressure due to sustained periods of demand at or in excess of available capacity), and would transform network performance during disruptions by providing alternative routings and faster recovery options.
Read the full report: Avondale–Southdown: Network Resilience Study Output Report