A review into how major train disruptions in Wellington earlier this year were handled has identified poor safety monitoring procedures and warns more government funding is urgently needed to bring rail infrastructure up to scratch in both the capital and Auckland.
Thousands of passengers were affected in May after KiwiRail's only track evaluation car (TEC) for the country broke down.
The rapid review into KiwiRail's performance in managing the metropolitan rail networks in Auckland and Wellington and the New Zealand rail system as a whole, was initiated by government ministers in response.
The report said safety standards and procedures were not keeping up with growing metro networks.
It said Waka Kotahi, as the safety regulator, was becoming more proactive but was still considered to take a 'light touch' approach.
The reviewers also said more central government funding was needed ahead of the opening of the Auckland Rail Link and to protect Wellington's tracks from slips and weather events.
Transport Minister David Parker said KiwiRail had already fixed specific failings that led to the commuter chaos in Wellington and the government wanted to see action on the other recommendations.
"The government has set a clear expectation with KiwiRail that it reports on its progress towards implementing each of the review's recommendations, to ensure it learns from the findings."
KiwiRail's chief executive Peter Reidy said the company took full responsibility for what had happened in Wellington in May and it was committed to providing a safe and reliable rail network for all commuters in both Wellington and Auckland.
"Commuter rail is very important to New Zealand, particularly as the country seeks to reduce its carbon footprint," he said.
"KiwiRail is focussed on supporting Metlink, Auckland Transport and the two metro rail operators (Transdev Wellington and Auckland One Rail) to run efficient services for commuters which will encourage more people off the roads and onto trains."
Reidy said the track evaluation car had been working for 41 years and the Wellington breakdown was the first time there had been a problem of this nature, but no safety problems were found.
"It was the equivalent of a Warrant of Fitness expiring. As a result, a 70km/h speed restriction had to be put in place on the line, which had consequences for how Metlink operated commuter services across the Wellington metro network," he said.
"It was primarily an issue scheduling the TEC inspection, and we have now rectified that issue."
Reidy said KiwiRail was looking forward to working through all the recommendations in the report with the Greater Wellington Regional Council and Auckland Transport.
"We have already made a number of changes within our business. These directly address specific failings that led to the TEC being unable to complete its required assessments of the Kāpiti Line in time and will help ensure its reliability in the years ahead."
General manager metros Jon Knight said KiwiRail was working hard to deliver on the government's investment.
"We recognise the importance of managing the commuter networks that enable nearly 22 million commuter journeys to take place each year," he said.
"We're replacing ageing track foundations across Auckland through our rail network rebuild; building a third main line to ease congestion on the busiest stretch of the network; extending the electrified section south to Pukekohe and building three new train stations in the growing, southern part of Auckland."
KiwiRail had also begun implementing a new, more proactive, infrastructure maintenance approach in the Auckland network and Knight said the company intended to extend that approach to Wellington.
An $800 million programme of works for the Wellington Region was also "designed to build a more reliable, modern and resilient railway which will allow for longer passenger trains and more of them", he said.