Part 2: Information about the condition of the state highway network

2.1
In this Part, we set out our findings about how NZTA:

• assesses the condition of the network;
• gathers information about maintenance, renewal, and capital works;
• stores information about assets;
• ensures that asset information is complete and accurate; and
• certifies consultants and contractors to collect and maintain asset information.

Our overall findings

2.2
NZTA has detailed systems, processes, and procedures for gathering and collecting information about the condition of the network. This includes inventory and condition databases, and requirements to ensure that the asset information that consultants and contractors collect and maintain is complete and accurate.

2.3
Although NZTA generally has detailed information about the condition of the road pavement and road surface, its main asset inventory databases for state highway roads and structural assets, such as bridges and tunnels, contain information that varied in how complete it was. Information about bridges, tunnels, and minor structures (for example, sign gantries, retaining walls, and culverts) was least complete.

2.4
Some of the asset information that NZTA requires consultants and contractors to collect and maintain is not critical for asset management, and some of the information provided by consultants and contractors is not always complete or timely. Some consultants and contractors are not appropriately certified to provide this information.

2.5
NZTA manages the risks caused by incomplete database information by relying on the knowledge, skills, and experience of consultants, contractors, and its staff, and their inspections of assets. It considers that relying on their personal knowledge is a reasonable approach to take when balancing the cost and value of the information it collects.

2.6
In our view, relying on personal knowledge (which depends on retaining skilled and experienced personnel) limits NZTA's ability to carry out accurate long-term planning. NZTA needs to improve how it captures useful and relevant knowledge in its asset inventory and condition databases.

2.7
As NZTA improves its required asset information over time, it needs to ensure that this information is cost-effective to collect and maintain, is as complete and up to date as possible, and remains useful.

2.8
We are pleased that NZTA has started scoping a new system to record asset information for all structures on the network.

2.9
In this Part, we make seven recommendations for improvement.

Assessing the condition of the network

NZTA regularly assesses the general condition of the road pavement and road surface, and regularly inspects structural assets. It needs to do more to record and bring together condition information for all structures on the network. NZTA also needs a more consistent and appropriate approach to tunnel inspections.

Assessing the condition of the road pavement and road surface

2.10
Each year, NZTA assesses and reports on the condition of the network's road pavement and road surface. The entire network is surveyed each year, using a data collection vehicle that assesses a range of condition measures. RAMM rating surveys, which test a sample of the network, are also carried out annually in each region.

2.11
The annual data collection survey and the RAMM rating surveys rate the condition of the road pavement and road surface against NZTA's technical levels of service for road pavement maintenance – for characteristics such as roughness, rutting, skid resistance, surface texture, and the surface condition index.

2.12
In general, the condition of the state highway road pavement and road surface meets current levels of service, but in recent years their condition has shown signs of increased rutting (see Figure 2).

Figure 2
The condition of the state highway network's road pavement and road surface

Assessing the condition of structural assets

2.13
No assessments are carried out of the overall condition of structural assets such as bridges, tunnels, and other structures (for example, large culverts, retaining walls, and sign gantries) on the network. This is because NZTA does not have a specific system for measuring, recording, or rating the overall condition of these assets. Advice we received as part of our audit confirmed NZTA's view that, at present, there is no effective model available for monitoring the deterioration in the condition of bridges and other structural assets because of the uniqueness of each structure in terms of design, construction, location, and use.

2.14
Although there are no assessments of the overall condition of structural assets on the network, experienced regional bridge consultants and contractors regularly inspect these structures. These inspections identify any defects and faults. Consultants record their findings and provide these inspection reports to NZTA. Their inspections are the basis for recommendations for maintenance and repairs or future management. NZTA told us that the consultants apply risk management principles when carrying out the inspections.

2.15
NZTA also told us that it has initial scoping work under way to prepare and put in place a central structures information system for all the structures on the network. Such an information system could collate and record inventory information (such as structural drawings, inspection reports, condition information, and long-term work plans) for more formal condition monitoring of all structures on the network. We are pleased that this scoping work is under way.

Inspecting bridges

2.16
More than half of the 4551 structures on the network are bridges. Figure 3 sets out an overview of bridges on the network. This includes:

• the results of a review of steel bridges on the network;
• the effects on bridges of allowing heavier vehicles to use the network; and
• information about Auckland Harbour Bridge.

Figure 3
Bridges on the state highway network

* The Land Transport Rule: Vehicle Dimensions and Mass Amendment 2010 introduced a permit system for road controlling authorities (like NZTA) to issue permits for vehicles up to 20 metres in length to operate above 44 tonnes on specified routes. The Rule amendment came into effect on 1 May 2010. The Ministry of Transport said that work to analyse the costs of allowing heavier vehicles to operate on specified routes would be part of putting the Rule amendment in place. It expected that some bridges would not be able to carry heavier vehicles and the permit system would exclude the heavier vehicles from these bridges – until and unless the bridges were strengthened or replaced.

2.17
For bridges on the network, NZTA's structures inspection policy sets out responsibilities for, and categories of, inspections, their frequency, and how they will be reported. Network management consultants carry out superficial monthly inspections of bridges on the network, and routine bridge maintenance and component replacement. Regional bridge consultants and contractors carry out general (every two years) and detailed (every six years) inspections of bridges on the network.

2.18
NZTA considers that its bridge inspection activities, and its knowledge of historical cost and activity data, reduce any risk posed by the lack of centralised inventory and condition information for bridges. Advice we received as part of our audit suggests that the scope and frequency of NZTA's inspections of bridges on the network is comparable with that of overseas roading authorities.

Inspecting tunnels

2.19
There are 16 tunnels on the network. The major tunnels are the Johnstones Hill (part of the Northern Gateway extension), Mt Victoria, Terrace, Lyttelton, and Homer tunnels. They range in age from one year (the Johnstones Hill tunnels were completed in 2009) to 79 years (the Mt Victoria Tunnel was built in 1931). A review by NZTA of all tunnels on the network looked at how well those tunnels meet international standards. Figure 4 has more information on the results of that review.

Figure 4
Results of a safety review of tunnels on the state highway network

2.20
NZTA's structures inspection policy treats tunnels on the network as "other structures" (like large culverts, retaining walls, and large sign gantries). For these other structures, the policy includes no detail about the frequency of inspections, or who will carry them out. NZTA told us that the network management consultants or contractors inspect other structures on a routine basis, as required in their contracts.

2.21
However, in practice, tunnels are treated differently to retaining walls and "other structures". NZTA told us that regional bridge consultants inspect tunnels. These inspections occur at a similar frequency to bridge inspections. However, there are regional variations. For example, the Homer tunnel in the Southland area is inspected by a contractor, not the local regional bridge consultant.

2.22
In our view, because the failure of a tunnel could have potentially significant effects on public safety and the functioning of important parts of the network, NZTA, as a priority, needs to review its structures inspection policy. The policy needs to ensure that there is a consistent and appropriate inspection approach to address the specific issues and risks associated with each tunnel.

2.23
Overall, as a priority, NZTA needs to complete the work it has started to introduce a system for collating and recording information about all structural assets and their condition (see paragraph 2.15), and use this information for more formal monitoring of the condition of these assets on a long-term basis, as reliable methods become available. This will enable NZTA to better monitor and address any issues and trends affecting the condition of these structures.

Gathering information about maintenance, renewal, and capital works

Consultants and contractors were not always providing NZTA with complete and, in some instances, timely information about maintenance, renewal, and capital works done on the network. Timeliness was a particular issue for some important information about capital works.

2.24
Network management consultants are responsible for providing NZTA with regular monthly and milestone reports outlining maintenance and renewal activity. Monthly reports provide updated asset information for the RAMM database, and milestone reports (prepared quarterly) provide updated asset information and maintenance expenditure information within their areas. For structural assets such as bridges, regional bridge consultants are responsible for providing NZTA with updated descriptive and structural information resulting from any changes to bridges and other structures within their regions.

2.25
For the five areas, we examined the completeness and timeliness of consultants' monthly and milestone reporting, from June 2008 to June 2009. In general, the reporting was not always complete and, in some instances, it was not timely.

2.26
Table 10 in Appendix 3 sets out our detailed findings for the 48 monthly reports that we checked. Overall, monthly reporting was usually provided to NZTA in a timely way. However, there were some exceptions. One report was missing for the Auckland Motorway area and one for the Southland area. Many reports were not signed by NZTA staff (as they are required to be). In the Northland and Wellington areas, no reports had been signed by NZTA staff.

2.27
Table 11 in Appendix 3 sets out our detailed findings for the 12 milestone reports that we checked. Overall, milestone reports were usually provided to NZTA in a timely way. However, there were some exceptions. All three reports for the Southland area were missing. For the Auckland Motorway area, one report was missing and two were incomplete.

2.28
NZTA told us that it introduced monthly and milestone reporting to keep regional staff informed about whether consultants and contractors were updating information in the RAMM database for their areas in a timely way. NZTA recognises that this reporting is important and wants to see it improve.

2.29
In each area, contractors carrying out capital works are responsible for ensuring that information about the work is complete and reliable. Contractors are usually required to provide NZTA with an "owner's manual". This outlines critical design aspects of the capital works that will require maintenance attention. NZTA requires the contractors to provide a draft version of the owner's manual when the work is physically complete.

2.30
It is the contractor's responsibility to then ensure that the appropriate inspections are carried out and that the RAMM database is updated. The completed information must be provided to NZTA within three months of the date of physical completion.

2.31
We examined how long it was taking NZTA to get asset information from contractors about capital works (for works completed from 2006 to 2009). In general, information about capital works was not provided to NZTA in a timely way. In some instances, it was provided much later than required.

2.32
We reviewed 44 capital works projects carried out in the Northland, Auckland Motorway, Wellington, and Southland areas. For more than half of these projects, the updated asset information had not been provided to NZTA within three months of the end of the project. Furthermore, in about half of these instances, asset information had been missing for more than two years.

2.33
Many of the NZTA staff we spoke to said that not receiving timely, complete, and quality information about capital works from contractors was a concern. This concern was highlighted in some of NZTA's reports. For instance, the 2009 RAMM validation reports (see paragraphs 2.57-2.63) for the Wellington and Auckland Motorway areas note issues with receiving information, or receiving only partial information, about new capital works projects. The Auckland Motorway report noted that most of the information associated with capital works projects that had taken place on that part of the network in the last few years was missing. That same report also noted that no information had been recorded in the RAMM database for a significant number of other recently constructed assets.

2.34
NZTA has made attempts at national and area levels to address the issue. Even so, NZTA staff told us that not receiving information about capital works in a timely way has been an issue for many years. In our view, because this information is important for keeping asset information complete and up to date, NZTA needs to ensure that all consultants and contractors provide complete and timely information about maintenance, renewal, and capital works carried out on the network. More complete and up-to-date information also allows NZTA to reduce its reliance on informal knowledge.

Storing information about assets

NZTA's main asset inventory databases for state highway roads, and for structural assets such as bridges and tunnels, contain information that varies in how complete it is. As NZTA improves its required asset information over time, it needs to ensure that this information is cost-effective to collect and maintain, is as complete and up to date as possible, and remains useful.

2.35
The RAMM database and the BDS database are NZTA's main inventory databases for assets on the network. The RAMM database contains detailed information about the road pavement and other related assets. The BDS contains information about bridges, tunnels, and other structures (for example, large culverts, retaining walls, and sign gantries).

2.36
We examined the completeness of the asset information in the RAMM and BDS databases for the areas we looked at.

Completeness of asset information in the Road Asset and Maintenance Management database

2.37
NZTA collects the information in the RAMM database to inform maintenance and renewal and for research, reporting, and contract management purposes.

2.38
The RAMM database includes information about the carriageway road sections, the carriageway surface, pavement layers and road markings, railings, shoulders, signs, lighting, drainage, minor structures, and retaining walls. It also includes information that is transferred from, and linked to, other systems. For example, it is linked to the Traffic Monitoring System, which monitors traffic to calculate existing and future demand on the network, and the Crash Analysis System, which analyses vehicle crashes on the network.

2.39
We checked the completeness of the information for carriageway road sections and for minor structures (including retaining walls) in the five areas that we looked at. We also checked a sample of the information for road sections in these areas for completeness of the data on the carriageway surface, pavement layers, and shoulders. Our checks covered information that NZTA has designated as "required", meaning that it is information that NZTA considers important and requires its consultants and contractors to collect and maintain.

2.40
Tables 1 to 6 in Appendix 3 set out in detail our findings for the information that we checked in the RAMM database. We found a high degree of variability in the completeness of the information.

2.41
Some information about the road pavement was largely complete – for example, the width and life³ of the carriageway surface, and pavement layer width and thickness. Much of the other information was much less complete – for example, lane and reserve widths, traffic counts and estimates for carriageway road sections, and the technical characteristics of carriageway surfaces. Required information about the dimensions and style of minor structures, including retaining walls, was largely incomplete. Also, details about how the information was provided, such as when it was added, and who had added or changed it, was sometimes missing.

2.42
We also note that, although it is not required by NZTA, there was no condition, risk, or financial value data in the RAMM database and variable information about the age of minor structures.

Completeness of asset information in the Bridge Data System

2.43
NZTA collects the information in the BDS database to inform maintenance and renewal of structures on the network, such as bridges, tunnels, and large culverts.

2.44
The BDS database specifies a set of information for bridges, tunnels, and other structures to help inform NZTA's asset management decisions. This information includes location, type, age, cost, dimensions, owner details, materials, capacity, geometry, and any weight limits.

2.45
NZTA, rather than its regional bridge consultants, maintains the BDS database. We checked how complete the information in the BDS database was for all tunnels on the network and for the bridges and other structures in four of the five areas that we looked at (excluding Auckland Harbour Bridge).

2.46
Tables 7 to 9 in Appendix 3 set out our findings in detail for the bridges, tunnels, and large culverts that we checked in the BDS database. As with the RAMM database, we found a high degree of variability in the completeness of the information in the BDS database.

2.47
Some information was largely complete, such as bridge age, length, and width information for three of the four areas. Other information was much less complete, such as design capacity/loading and vertical clearance information for bridges. For the Northland and Auckland Motorway areas, design capacity/loading information was missing for most bridges. For bridges that crossed the state highway or other local roads, vertical clearance information was missing for a third of the bridges that we checked. Age and dimension information for tunnels and large culverts was also largely incomplete.

2.48
Additionally, we note that there is no central storage of hard-copy information about Auckland Harbour Bridge. The information was held in various locations by several entities. Historical information was held by the NZTA library, the Auckland Harbour Bridge Library, Opus International Consultants Limited, and Archives New Zealand. Current documentary information on the Bridge is primarily held by the specialist structural engineering consultants. NZTA should consider consolidating and centrally storing all relevant hard-copy information about Auckland Harbour Bridge to help effective and efficient long-term, whole-of-life management of this asset.

Significance of the information missing from the Road Asset and Maintenance Management and Bridge Data System databases

2.49
We expected NZTA to have information that was as complete and accurate as practicable, and that was relevant and useful to understanding and managing the assets.

2.50
NZTA told us that its information needs change over time, some of the requirements we checked were recent, and it is sometimes impractical and not cost-effective for NZTA to get all the information it needs immediately. It said that some information is provided over time and can take several years to gather. For example, to get full information on pavement structure in the RAMM database would require digging a test pit in each section of road. Instead, information is collected when the surface and/or pavement of a road is worked on.

2.51
Also, NZTA said that it needs to make priority decisions about what asset information it collects and maintains, based on the risk and value of each asset and the cost of collecting and maintaining that information. For example, NZTA told us that it did not collect and maintain information about all minor structures, such as retaining walls, on the network for this reason.

2.52
NZTA told us that not all information about structures is held in the BDS database. NZTA supplements the information in the BDS database with information from physical inspection of structures and other sources (for example, structural drawings), to inform maintenance and renewal needs and to make assessments such as the load-carrying capabilities of bridges.

2.53
NZTA said that it had the critical information it needed to make informed asset management decisions, and that the incompleteness in the RAMM and BDS databases did not have a significant effect on its asset management processes. NZTA told us that its risk management processes, such as its inspection routines, take into account the information it does not have.

2.54
We recognise that, in deciding what information it requires, NZTA needs to balance the cost of collecting and maintaining the information with the value of such information providing more effective and efficient asset management. In our view, NZTA has not been sufficiently systematic or transparent in making these cost-value trade-offs for its information requirements. Over time, the priority and relevance of some of its information requirements have become unclear, leading to some of the variability in the completeness of its asset inventory information that we found.

2.55
NZTA told us that some of the RAMM database requirements that we checked were not used, and one should not have been a requirement. Also, some of the requirements were, in our view, impractical. For example, the RAMM database requires traffic count and traffic estimate data for carriageway sections, but for most carriageway sections on the network it is possible only to estimate the traffic flow.

2.56
NZTA risks wasting time and resources collecting and maintaining information that is not useful for asset management purposes. Conversely, NZTA risks not carrying out its maintenance and renewal work in a proactive and co-ordinated way if it does not have relevant information readily available, particularly on condition and risk. Information that is useful for maintenance and renewal of roads and all structural assets on a long-term, whole-of-life basis needs to be collected and available. Over time, NZTA needs to improve its asset information ensuring that it is useful, as complete and up to date as possible, and cost effective to collect and maintain.

Ensuring that asset information is complete and accurate

Consultants had a range of quality assurance systems and asset information validation requirements. Some consultants were not required to carry out validation checks.

2.57
In each area, NZTA requires the network management consultants to have their own quality assurance systems. These systems are meant to ensure that the asset information the consultants provide to NZTA is recorded correctly and in a timely way. Network management consultants had a range of formal and informal quality assurance systems and peer review and support processes.

2.58
None of the consultants or contractors in the areas that we looked at had checks to identify and effectively rectify instances of non-compliance with contractual or procedural requirements (for example, late reporting or incomplete compliance with reporting requirements). In our view, NZTA needs to ensure that all the consultants and contractors that it engages have quality assurance systems that include checks to identify and effectively rectify instances of non-compliance.

2.59
Consultants are generally required to carry out annual validation checks to ensure that asset information on the network is accurate. The details of how much and which information consultants are required to validate depends on the type and length of the contract that a consultant has with NZTA.

2.60
There were a range of contractual requirements for the areas that we looked at. In one area, NZTA required the consultant to check 33% of the asset information annually. In two other areas, the consultant was required to check 20% of the asset information annually. In another area, there was no requirement to validate asset inventory information. For the Auckland Harbour Bridge area, the consultant was required to carry out a "baseline" verification of both the condition of the Bridge and the information held about the Bridge.

2.61
We checked to see whether the consultants had carried out the required validation checks since the start of their contracts. We found that the required checks had been carried out. We also examined consultants' reports describing the outcomes of the validation checks. These reports varied in format, layout, level of detail, discussion of methodologies used, and results found. Although an initial baseline verification was carried out for Auckland Harbour Bridge, the information was not checked for accuracy.

2.62
In our view, NZTA needs to ensure that all relevant maintenance and renewal contracts have clear and regular requirements to validate asset information, and to ensure that the results are consistently reported. This will not only improve the quality and integrity of NZTA's asset information, but it will also provide a consistent template for consultants to use when carrying out validation checks. Because it is such an important asset, these requirements are particularly important for Auckland Harbour Bridge.

2.63
For Auckland Harbour Bridge, NZTA needs to carry out a full validation check (to validate the asset information it holds and ensure that it has a full record of the component parts of the Bridge) after the completion of the box girder strengthening project (described in Figure 3). In our view, this will help reduce variability in the quality and integrity of NZTA's information about Auckland Harbour Bridge.

Certifying consultants and contractors to collect and maintain asset information

NZTA's register of consultants and contractors certified to collect, update, and audit RAMM database information was not up to date at the time of our audit. Not all consultants and contractors were appropriately certified.

2.64
Network management consultants and contractors are responsible for gathering, collating, and maintaining information in the RAMM database. Regional bridge consultants are responsible for gathering and collating information, and providing it to NZTA to be entered into the BDS database.

2.65
In each area, RAMM managers (usually a staff member of a designated network management consultant) are responsible for collecting, updating, and auditing information for the RAMM database. Other network management consultants or contractors may also be involved in collecting information for the RAMM database.

2.66
Since 2007, there has been a requirement that all consultants or contractors who collect, update, and audit such information are appropriately trained and certified. NZTA's national office maintains a register of all those who have been trained and certified, including records of their level of certification and when that certification expires.

2.67
This accreditation system was introduced to lift asset information quality, and NZTA believes that the quality of the information has improved. However, we found some matters that need to be addressed. At the time of our audit, NZTA's register had not been updated for training that had taken place nearly three months before our audit. NZTA should keep its register up to date.

2.68
After the register had been updated, we found that one of the RAMM managers for the areas we looked at did not have the required level of certification. In one of the areas, uncertified staff of the contractor were collecting information, and the contractor was unclear about the training required.

2.69
Having appropriately qualified people collecting, updating, and auditing asset information is important for ensuring that asset information collected on NZTA's behalf is accurate and reliable. In our view, to continue improving the quality of its asset information, NZTA needs to ensure that all the consultants and contractors it engages are appropriately certified. This should include NZTA regularly checking the certification of its consultants and contractors.

3: See Appendix 3, Table 2. "Modified life" is the most useful indicator of carriageway surface life.