Auditor-General's overview

New Zealand Transport Agency: Information and planning for maintaining and renewing the state highway network.

The state highway network (the network) – made up of roads and their associated structures such as bridges and tunnels – is one of the country's major infrastructural assets. It carries about half of New Zealand's annual road traffic and is valued at almost $29 billion. The network is vital to New Zealand's economic growth and productivity, and the Government plans to invest significantly in it during the next 10 years.

Because of its importance, the network needs to be safe for users and in a reliable condition. In 2009/10, the New Zealand Transport Agency (NZTA) spent about $514 million on maintaining and operating the network.

NZTA produced its latest report on the condition of the network in 2009. The report showed that the condition of the network met the expected levels of service – but it also concluded that some levels of service were just holding steady over time and that, nationally, the network continued to show signs of deterioration caused by rutting.

How NZTA maintains and renews the network is the focus of two performance audits by my staff. This report outlines the findings of our first audit, looking at how well NZTA gathers and uses information about the condition of the network to plan for maintenance and renewal work. We intend to publish a second report next year, looking at how well NZTA carries out that maintenance and renewal work.

Our overall findings

NZTA had good descriptive and condition information about the state highway roads, and it had a planning framework that enabled it to use this information for day-to-day maintenance and renewal of the road network. However, not all of its information was complete, especially for structures such as bridges and tunnels. Its long-term planning was also incomplete at the time of our audit. NZTA is aware of these issues and has been working to address them.

In my view, to more effectively plan and prioritise maintenance and renewal work, especially in the long term, and to better meet the expectations of road users, NZTA needs to:

  • improve the quality and completeness of its asset information, particularly for structural assets such as bridges, tunnels, and retaining walls; and
  • more systematically focus planning for maintenance and renewal work on the most important areas.

Improving the quality and completeness of asset information

NZTA assesses the condition of the state highway roads annually through a data collection survey and other means. For structural assets, NZTA relies on the knowledge, skills, and experience of consultants, contractors, and its staff. By regular inspections, they assess the condition of these assets and identify faults requiring repair. We understand that NZTA, along with overseas roading authorities, does not yet have an effective model available for monitoring deterioration in the condition of bridges and other structural assets. But relying on personal knowledge (which depends on retaining skilled and experienced personnel) restricts NZTA's ability to accurately plan for the longer term, because there is a risk that important knowledge is lost when people move on.

NZTA's main asset inventory databases for state highway roads and structural assets contain information that varied in how complete it was. Information about structural assets – such as bridges, tunnels, and minor structures (for example, small culverts and retaining walls) – was least complete.

Relevant and useful information about the whole network enables effective planning for maintenance and renewal work. Not all of the information that NZTA required consultants and contractors to collect was critical for asset management. Consultants and contractors were not always providing NZTA with important and timely information.

It is important that NZTA has the asset information that it needs to make sensible and informed investment decisions about the whole network. NZTA needs to clarify which information is critical for asset management purposes, and make sure that consultants and contractors collect and maintain critical information in a timely way.

NZTA needs to refine its information over time, ensuring that the information it requires remains useful and cost-effective to collect and maintain, and that the information is as complete and up to date as possible.

When reliable methods become available to monitor the condition of structural assets such as bridges, NZTA needs to establish more formal monitoring of the condition of these assets. This should lead to more cost-effective maintenance and renewal of bridges and other structural assets in the long term.

More systematic and focused planning for maintenance and renewal work

NZTA, like its predecessor organisations, plans maintenance and renewal work to meet levels of service (for example, keeping roughness below certain levels and maintaining levels of skid resistance). These levels of service have been in place for many years. NZTA plans the level of maintenance and renewal, and prioritises work, based on what has been spent in the past and the information it has on the condition of the roads, with the aim of preserving the condition of the network and maintaining safety.

NZTA is making efforts to embed more formal and consistent asset management planning across the network. NZTA needs to complete, continually review, and improve its asset management plans and make sure that they are closely aligned with operational plans. This will help to focus maintenance and renewal work, long term, on the most important areas.

NZTA's overarching levels of service for maintaining road pavement (in relation to roughness, rutting, skid resistance, and surface texture) are comparable with those of similar overseas roading authorities. But, in our view, its underlying levels of service for pavement maintenance (for example, response time for filling potholes) and for corridor maintenance need to be better informed by the needs of road users to ensure that the service levels are well aligned with road users' expectations.

NZTA needs to clarify how it determines levels of service, and it needs to continue to actively engage with road users and work with its Board. This will help the Board make well-informed decisions about allocating and investing funding from the National Land Transport Fund.

The New Zealand Transport Agency's response to our findings

NZTA was aware of the need for the improvements we have recommended and, during the course of our audit, had started, or was planning, to work on them – and to work on better informing the decision-making of its Board.

NZTA is committed to preparing and implementing a national asset management plan for all activities and this will include annual feedback from road users. NZTA has told us that all our audit findings can be incorporated into its current work programme.

Our recommendations

I have made 10 recommendations to support and enhance the improvements NZTA is making. This report also suggests several matters for NZTA to consider. My staff will be following up on NZTA's progress with the recommendations and the suggestions.

I thank the NZTA staff involved for their help and co-operation during this audit.

Signature - LP

Lyn Provost
Controller and Auditor-General

6 September 2010

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