As we learn more about the how our road network holds up to possible unexpected disruptions and other unexpected disruptions, we better understand where we need to invest - both to increase its resilience and to provide better indicators and predictors of potential disruption.
This page provides nationally consistent information on the risks of high impact low frequency events (such as earthquakes). It also provides a range of tools and tips in a business case context to help develop interventions and agreed responses to improve the resilience of networks. It also provides nationally consistent information on the risks of high impact low frequency events (such as earthquakes).
These tools help us and our suppliers identify and evaluate resilience risks and issues, and their likely impacts as well as prioritise potential responses.
Resilience evaluation process
This process map will help assess the resilience issues on a network. It contains links to various tools and resources that will help you build a business case for investment.
These tools are aligned to the business case process. Depending on the scale and nature of your problem a minor improvement (less than $300k), or enhanced resilience (more than $300k) may be a more appropriate response. Funding application forms for these can be found on the resources and information page.
Please note that this page, and the guidance and tools it contains, will be updated regularly in the coming months. If you have any questions or need further information, please contact resilience-infrastructureplanning@nzta.govt.nz .
Resilience in the strategic business case
This note gives examples and insights using a resilience lens on the planning process and can be used by anyone developing a strategic case to incorporate resilience into their assessments.
Hazard exposure scan
The maps section of our site provides an assessment of key natural hazards focussing on low frequency, high impact events (such as earthquakes) that may impact the availability of the network, and includes an assessment of the extent and duration of the outage.
Identify detour routes
Our alternative routes tool is still in development (expected mid 2017), but you can access the pilot tool .
You can get further information from the relevant Network Outcomes Contract (NOC) Emergency Procedures and Preparedness Plans. These can be found by NZTA staff on InfoHub. External users should contact their regional NZTA office.
Note that alternative routes with start and finish points are also a useful method for breaking a long corridor into segments for a more accurate assessment of the resilience risks to a particular area.
When a section of our roading network becomes unexpectedly out of action we need suitable detour routes to ensure people can finish their journeys.
We have built interactive detour maps that with a handful of clicks will identify the agreed alternate routes, comparative distance and travel times, which vehicle types each route is suitable for, and other key pieces of information.
One Network Road Classification assessment
The One Network Road Classification (ONRC) provides guidance for the resilience customer level of service that is expected for each road category (national, regional).
The gap assessment provides a simple table for documenting your assessment against the ONRC. This assessment will help in determining the scale of the problem, and will also help in assessing the strategic fit of the project.
Resilience risk priority
With an understanding of the natural hazards, the expected customer level of service on the route and the availability of alternative routes you will have sufficient information to determine whether there is a significant resilience problem and the justification to proceed to a programme business case. Guidance for this assessment will be provided soon.
Resilience in the programme business case
The insights report gives examples and insights using a resilience lens on the planning process and can be used by anyone developing a programme business case to incorporate resilience into their assessments.
Detailed data collection
The programme business case stage requires that a more thorough data collection and analysis is undertaken.
Low probability high impacts event: This guide builds on the national hazard exposure scan methodology, aligning with the expectation that a more thorough assessment of the problems is explored in the programme business case. The guide steps you through the process of a more thorough assessment at the regional/corridor level, focusing on the natural hazards which are generally low frequency, high impact events (such as a large earthquake).
High probability low impact events: An assessment of the high probability, low impacts events must also be undertaken. This information can be requested from the TREIS database via our regional operational staff (including NOCs and other contractors).
This template will help collate and represent the data from TREIS in a simple way, and can be copied into a report.
Assess the level of service gap
A more thorough assessment of the customer level of service is expected in the programme business case, than the strategic case.
This framework takes a closer look at the profile of event outage durations and frequency and recommends a process response type taking the ONRC category into consideration. This will help inform the development and assessment of your programmes.
The criticality framework is to help refine the importance of your corridor, looking wider than just traffic volumes, by considering access to lifelines utilities and essential service needs. Your local civil defence group might be a good starting point for collecting this information. You can find contact details on the civil defence website .
This is a different approach to assessment against the ONRC. This approach considers whether the ONRC classification makes sense from a resilience point of view, and whether the corridor should be treated as either a higher or lower category. In this situation you may need to revisit the evidence base in your strategic case to ensure that it still aligns with the ONRC category.
Develop and assess programme of options
If you identify a gap in the level of service your network provides, you need to develop and test a range of approaches to address this.
The programme business case will guide you through the process of developing these programmes, including a social and economic impact assessment.
Economic assessment: You need to assess the economic impact of your proposed programmes. The Modelling the economics of resilient infrastructure tool (MERIT), which supplements the standard economic evaluation manual-based benefit-cost analysis, assesses the economic impact of a potential (or actual) network outage. The tool and related supporting resources can be found under the 'Economic assessment' heading . Work has been done to test the MERIT tool in action, on the SH3 Manawatu Gorge 2011-12 outage .
Social assessment: Similarly you should consider the impact on society if your link becomes inaccessible. We will shortly provide a framework that will help you assess the potential social impacts for communities of particular network outages.
Once you have selected your preferred intervention it is worth reassessing it against the level of service framework to ensure that your invention will close the gap in level of service.
If you have any questions or need further information, please contact resilience-infrastructureplanning@nzta.govt.nz .