Climate change: interim guidance for adaptation and mitigation


Climate change mitigation and adaptation are key considerations when optioneering.

Note: This is the most up-to-date information available. This page will be updated when emission targets and adaptation plans are in place.

Key questions

Key questions to ask when considering greenhouse gas (GHG) emissions are:

  • Is this alternative or option, on its own or as part of a package or programme, likely to increase, have no impact or reduce demand for travel by car, now or in the future?
  • If the alternative or option, on its own or as part of a package or programme, is likely to increase or have no impact on demand by car:
    • Are there climate-friendly alternatives or options that could reduce demand for travel by car (and therefore emissions)?
    • Consider complementary activities to mitigate the potential increase in emissions (either within the same package or programme, or forming part of another package or programme).
  • Is the activity, on its own or as part of a package or programme, likely to reduce reliance on travel by car, now or in the future? If so:
    • What is the potential scale of the reduced demand? (eg reducing vehicle kilometres travelled (VKT) or increased mode share for public transport/active modes)
    • What supporting interventions may be needed to optimise emission reductions (eg incentives, parking management or workplace travel planning)
  • On balance, is the regional land transport plan (RLTP) (for major urban areas) likely to increase demand, make no difference to demand, or reduce demand for travel by car? If the RLTP is likely to increase or have no impact on demand, then mitigation of emissions arising from travel by car is expected.


Investment in ‘climate friendly’ activities does not automatically mean that transport emissions will reduce. Research tells us that for emissions to reduce, integrated packages of interventions must be specifically designed and optimised to reduce emissions through avoiding or reducing reliance on travel by car, and/or shifting to other more energy-efficient modes. This means taking account of things like land use, provision of and proximity to shared and/or active modes, how efficient the movement of shared/active modes is (eg bus prioritisation lanes), and what demand management interventions are in place to support lasting behaviour change (eg parking management, reduced public transport fares, etc). Standalone climate-friendly activities are unlikely to achieve sustained reductions in emissions.

Adaptation: addressing the impact of climate change

Land transport infrastructure is exposed to the effects of climate change, including sea-level rise, inundation, temperature changes (eg affecting pavement surfaces), extreme weather and changing weather patterns, eg lower snowlines. Waka Kotahi NZ Transport Agency has a key role in preparing for climate change through its investment function.

For the land transport sector, climate change adaptation is focused on reducing the vulnerability of the land transport system and its users to the impacts of climate change by building adaptive capacity and resilience. Effective climate change adaptation will require the analysis of current and future climate change scenarios:

  • assessing climate vulnerabilities and identifying adaptation options
  • reviewing and appraising adaptation options
  • integrating climate change adaptation into land transport planning and decision making.

New Zealand’s approach to addressing climate change adaptation will be set out in a National Adaptation Plan (NAP) to be developed by the Ministry for the Environment (MfE) and informed by the National Climate Change Risk Assessment (NCCRA).

The NAP will take a cross-government approach to address climate risk in a more comprehensive manner and set out expectations for central government, Crown entities and agencies. The NAP will provide a high-level strategic framework (including performance metrics) that will serve as an umbrella for sector-specific strategies.

Waka Kotahi is required to show it is integrating climate change adaptation into its planning, investment and decision-making. Projects should identify how climate change adaptation has been considered and planned. A national direction and assessment framework being developed by central government will provide national direction and high-level guidance on expected responses. More detailed guidance on assessing climate change adaptation and incorporating it into planning, design, operation, maintenance and replacement will evolve. The guidance here will be updated as this work progresses. In the meantime, Waka Kotahi’s National Resilience Programme Business Case (PBC) and Coastal Inundation Report provide an evidence base for identifying areas that are subject to extreme or high risk from natural hazards and climate change. Initial considerations should include:

  • risk of rail and pavement heat stress
  • positive effects, eg mode share and lower requirements to build hard infrastructure
  • coastal inundation risk
  • inland flood risk
  • risk from rockfall and land slips induced by changing weather patterns.

Mitigation: addressing one of the causes of climate change – transport greenhouse gas emissions

Land transport greenhouse gas emissions (GHGs) are concentrated in our fastest growing cities and they are driven primarily by the light vehicle fleet. The impact of alternatives and options on land transport GHG emissions for the moment therefore applies to light vehicle travel in major urban areas.

Until transport GHG emission budgets and associated emission reduction plans are confirmed by the Climate Change Commission and the government, we do not expect emissions impacts to be expressed in traditional terms of tonnes of CO2e. It is also important to note that impacts of interventions on GHGs are best assessed at a programme level. With these two matters in mind, this interim guidance identifies climate-friendly activities with greater potential to reduce emissions.

Climate-friendly activities with potential to reduce GHG emissions

When considering transport interventions that reduce transport GHG emissions, the Avoid – Shift – Reduce Model is useful:

  • Avoid/Reduce interventions aim to avoid or reduce the need to travel, or the time or distance travelled by car, while improving accessibility (eg integrated land use and transport planning for urban form supporting better proximity to services and employment and better access to shared/active modes).
  • Shift/Maintain interventions focus on mode shift from travel by car to travel by more energy-efficient shared and/or active modes such as public transport, walking, cycling or micro-mobility vehicles.
  • Improve interventions focus on improving the energy efficiency of the vehicle fleet (eg by supporting increased uptake of electric vehicles).

This interim guidance relates primarily to Avoid/Reduce interventions and Shift/Maintain Interventions.

Activities that enable people, business or communities to avoid or reduce the need to travel (particularly by car), and/or shift to energy efficient modes such as public transport, walking and cycling, are considered ‘climate friendly’. These are generally low or no-carbon activities, with the potential to reduce overall GHG emissions if designed for that purpose and delivered at scale.

The table below shows some examples of climate-friendly transport and land use activities and their relative potential to reduce transport GHG emissions, if designed for that outcome:

Activity Potential for GHG emission reduction
Integrated land use and transport planning that helps people to avoid or reduce their need to travel (eg intensification around existing transport nodes; transit-focused greenfield development)  M - H
Public transport infrastructure and services, including activities to encourage greater use of public transport (including passenger rail, bus transit, light rail, rapid transit)  M-H
Walking and cycling improvements, including activities to encourage greater use of active modes (eg safer, more attractive, promotional activities)  M-H
State highway/local road improvements and maintenance: Focus on network optimisation and management, eg traffic management to minimise emissions generation, reprioritisation for shared/active/low-carbon modes, footpath maintenance, traffic calming etc.  L-M
Demand management, including mode shift education, promotion, parking management, road pricing, school/workplace travel planning, freight logistics planning, etc. Focused on helping people, business and communities avoid or reduce their need to travel and/or shift from travel by car to travel by shared and/or active modes.  L-H
depending on scale and ambition

Activities that may not be as climate friendly include investment in additional road capacity for cars or interventions designed to maximise the throughput of vehicles on an existing network, without any mitigating activities such as provision for bus or high-occupancy lanes. Both types of activities may increase or induce demand for (and the ease of) travel by car. When such activities cannot reasonably be avoided, the question to then consider is how any potential increase in emissions from increased demand can be mitigated through a programme of climate-friendly activities. It’s also important to keep in mind that increasing road capacity or vehicle throughput isn’t necessarily contrary to reducing emissions, for example if it accommodates high-occupancy vehicles or low/no carbon vehicles.