Adaptation anticipates and deals with the effects of climate change that are unavoidable, helping to build greater resilience by harnessing innovation and responding to impacts such as rising sea level and coastal hazards or droughts. Most adaptation action takes place at a local and community level (e.g. through land-use planning) but may have implications for the region (e.g. beach amenities, council services, coastal roads).

Mitigation is about taking action to reduce greenhouse gas emissions so that the severity of climate change will be lessened.

Climate change mitigation and adaptation are closely linked: the more we collectively take action to reduce our greenhouse gas emissions, the better the chance we will have less severe impacts to adapt to in the future. Some actions we can take contribute to both areas, for example, planting coastal vegetation which absorbs carbon (mitigation) and protects properties at the same time by stabilising coastlines (adaptation).

Nelson City Council is following the Ministry for the Environment’s Coastal Hazards and Climate Change Guidance for Local Government, using the DAPP framework - Dynamic Adaptive Pathways Planning - an iterative 10-step framework to develop and implement a long-term strategy for areas that may be affected by coastal hazards and climate change effects, such as sea-level rise.

The 10 steps in the DAPP framework are structured around five key questions: what is happening, what matters most, what can we do about it, how can we implement the strategy, and how is it working?

The Council is currently working on the early stages of this process which involves the assessment of coastal hazards, understanding the community values that could be affected by increasing coastal hazards, and developing values-based objectives that can be used to inform adaptation responses.

In June – August 2022, Council will be engaging with the community to find out what our community thinks is important to achieve through our adaptation response (for example, ensuring access to the beach for walking, and for houses to be climate and flood resilient). Following this engagement, Council will develop objectives to help guide coastal adaptation planning, and from 2023 onwards, location-specific adaptation options for Whakatū Nelson will be developed. Council will engage with the community at certain stages throughout the process, so that adaptation options are informed by the community’s views.

Council is initially prioritising coastal adaptation (including the lower Maitai River), however, other rivers, streams and climate change risks will also be assessed and form part of the long-term strategy for preparing for and adapting to the impacts of climate change.

Council has engaged with the community several times in recent years on either coastal or river flooding. Community members have generally found the coastal hazards and flood maps informative although there is a range of perspectives regarding the potential impacts of climate change. Many people have shared their concerns about flooding and told Council that they value their housing, access to the beach and feel that action is required.

Concerns have also been raised about impacts of sea level rise on communities, our city centre, our infrastructure and impacts on insurance.

As part of the DAPP process, we will use what the community has previously told us and the current engagement will build on this to identify community values and desired outcomes.

The possible options for addressing coastal hazards and river flood hazards can be broadly grouped into four categories: accommodate, protect, avoid and retreat. These are depicted below and options under each of these categories can include planning, engineering and building community capacity through increasing awareness and education.

Accommodate: Measures under this category could include minimum ground or floor levels for buildings, temporary barriers to prevent flooding, building setbacks and raising community awareness through mapping and education.

Protect: Protect measures are the only measures that seek to reduce the impact and extent of the hazard. Examples of these include beach nourishment including the restoration of sand dunes, planting, coastal stopbanks and groynes (walls or barriers built out into the sea from a beach), tidal gates, and in limited circumstances, sea walls. For lower Maitai River flooding additional measures could include channel widening, upstream flood detention to reduce river flows, and flood warning systems. It is important to note that many protection measures are likely to have finite durability in the context of climate change, and that there may be an element of residual risk if a protection structure fails during a flood event.

Avoid: Measures under the avoid category include land-use planning restraints to avoid putting people in harm’s way such as limiting housing in a particular zone or area.

Retreat: Measures under the retreat category, though enabling the gradual retreat of people and property to safer ground over time, will depend on the long-term impacts of coastal and river flood hazards. Central government is currently working on a legislative framework for managed retreat through the development of the Natural and Built Environments Bill, National Planning Framework, Strategic Planning Bill, and Climate Adaptation Bill.

The strategy to adapt to ongoing changes climate needs to be dynamic and responsive over the long-term, taking into account the latest science and data as it comes to light and keeping tabs on emerging impacts. Given the nature of climate change risk, the Council wants to develop a climate adaptation response that provides for and supports longer-term city and community resilience. We cannot wait for uncertainties to be reduced (if at all) before making decisions, and we need to adopt a planning approach that can accommodate changes and encourage investment in adaptation without locking in investments that make future adjustments difficult and costly. Key to this is understanding climate change risks and how they affect particular locations, including the people and infrastructure within them. Learning more about community views and preferences is also of critical importance, and it is not until we have all of this information that we can start to properly develop possible solutions for these complex issues.

The costs associated with different adaptation options and solutions also need to be understood, and this may be affected by the resource management reforms that the government is progressing. If these reforms are passed into law, the Climate Adaptation Bill - which is currently being developed - may be important for determining the balance of responsibility between central government, local government, private property owners, and the private sector. There is the potential that this new national-level framework and direction will drive further conversations with the community on specific options and pathways planning for the long-term.

Managed or planned retreat is a proactive approach that enables communities or suburbs to plan (usually over decades) the relocation of homes and other assets, activities and sites of significance away from areas facing higher and more frequent future risks. It is one option we can consider when deciding how to adapt to the impacts of climate change and will need to be informed by: the current and future levels of risk, setting signal and trigger levels for retreating (which may be decades ahead), and community preferences and risk tolerances.

Managed retreat involves a complex and multifaceted set of issues. For example, there will be implications on social equity, community dislocation, cultural impacts, ecological impacts, transportation, council services and accessibility, recreational impacts and economic impacts – among others. These inter-related issues all need to be considered carefully and responded to. However, on the flip side, low-lying coastal areas will experience increasing frequency of damage and disruption, including post-event recovery processes, which need to also be considered,

The complexity surrounding managed retreat is why central government is developing new climate change adaptation legislation, which is expected to create a nationally - consistent framework for addressing these complexities and involve all key stakeholders.

Central government recently consulted on a draft National Adaptation Plan, which is intended to outline the government’s objectives, strategies, polices and proposed actions for addressing climate change risks. The draft National Adaptation Plan contains content on system-wide actions; the natural environment; homes, buildings and places; infrastructure; communities; the economy and financial system; a research strategy; and monitoring and reporting. Council made a submission on this consultation. Our submission can be found here.here.

Central Government also consulted on managed retreat proposals, in order to inform the initial stages of policy development for the Climate Adaptation Bill, which is intended to provide tools and processes to plan and implement managed retreat proposals. Managed retreat is a transformational approach to eliminate exposure to intolerable risk. It includes the idea of strategically relocating assets, activities and sites of cultural significance (to Māori and non-Māori) away from at-risk areas within a planned period of time. Managed retreat might be used in response to any climate change impact or natural hazard, whether or not that hazard is caused or exacerbated by climate change.

The NZSeaRise data (searise.nz) takes into account the local vertical movement of our land as well as the latest sea-level rise projections for the Nelson region derived from the latest assessment report of the Intergovernmental Panel on Climate Change (IPCC).

The data over a period 2003-2011 shows that the urban area of Whakatū Nelson is subsiding (sinking) by an average of around 2 mm per year. This combined with the latest sea-level rise projections, suggests urban areas of Nelson will face between 0.4 - 0.7 metres of relative sea-level rise by 2070 (50 years’ time). Over a longer, 100-year timeframe, by 2120 the projections show a rise in the range 0.8 and 1.7 metres (depending on how effectively global emissions can be reduced). These projections are higher than previous Ministry for the Environment (2017) projections which is largely due to taking into account the rate of land subsidence and also increases globally in sea-level rise projections for all climate scenarios.

Council staff are looking at how the new information affects our adaptation response planning.

Council’s new multi-purpose development, with a library at its heart, has brought conversations about climate change to the fore. This proposed development is part of our city centre, much of which may potentially be impacted by climate change.

Coastal and riverside areas of our city are culturally and economically important to Nelsonians, so it is vital that any decisions we do make to adapt to climate change are well-considered, based on strong data, not rushed, and made in consultation with the community.

Council is committed to this transformative project, and we will continue to evaluate the suitability of the site at key steps through the process. Council staff are looking at how the new NZSeaRise projections could impact the library project and will report back to elected members and the community in due course.

At this stage, the evidence is not telling us to avoid the riverside site. However, flood modelling will continue to be revisited when new evidence arises or there are changes in legislation that may impact the development.

With construction currently 2-3 years away, we have time for our climate change conversations around the future shape of our city, and how it should adapt to climate change, to progress.

More broadly, Council is also considering how the latest NZSeaRise data may affect requirements for ground and floor levels for subdivision and building. It is expected that Council will work with the Tasman District Council to update the Inundation Practice Note (IPN).

In the development of each of these documents, consideration has been given to coastal and river flooding. Reviews of these documents will be able to incorporate new information, as knowledge of the impacts of these hazards continues to increase over time.

The proposed Housing Plan Change (Plan Change no.29) aims to provide more housing opportunities as a response to the demand for housing in Nelson by amending the Nelson Resource Management Plan (NRMP) rules to allow for greater residential intensification. In seeking to find a balance between the need for housing and the potential impacts of coastal flooding in Nelson, Council will consider limiting residential intensification of areas potentially impacted by 1m of sea level rise. Additionally, this plan change will consider how to apply the latest river flood mapping to minimise significant natural hazard risks from new development.

It is anticipated that Council may amend its Resource Management Plan to reflect the outcomes of the DAPP process, and to update natural hazard maps. In addition, it is highly likely that the replacement RMA legislation will require amendments, review or full replacement of the Resource Management Plan over time.

Preparing for climate change requires strong leadership and a whole-of-Council approach through which the community is engaged in discussions on options and solutions. Climate change has been established through the Long Term Plan 2021 – 2031 as “a lens through which all Council work programmes are considered”. Council’s work programme is focussed on both reducing greenhouse gas emissions (mitigation) and preparing for climate change impacts (adaptation).

Our response prioritises working in partnership with iwi, central government, business, schools, community groups, households, and individuals to improve the resilience of the Nelson region. We are partnering with Nelson Tasman Climate Forum and Businesses for Climate Action to support climate change projects.

Council’s climate change work includes:

• Reducing its operational greenhouse gas emissions.
• Supporting and providing leadership on actions to reduce emissions across the community
• Preparing to manage and lower risk by adapting to climate change impacts, especially in relation to sea level rise (and associated coastal hazards) and river flooding.

Key pieces of work we are progressing includes:

• Implementing Te Mahere Mahi a te Āhuarangi Climate Action Plan (nelson.govt.nz/climate-action-plan) approved in November 2021, which includes all the climate change projects that Council is working on.
• Developing a strategic framework for climate change that will set the long-term direction and specific goals to guide climate action in Nelson.
• Developing a comprehensive inventory of Nelson’s greenhouse gas emissions, to enable us to track progress on reducing emissions.

Council has completed the verification of its fourth operational carbon footprint inventory for the financial year 2020/21. The results of this inventory have been published on the Council website, and show a gradual decrease in Nelson City Council’s operational emissions.

Our response to climate change provides an opportunity to come together as a community and determine what is most important to us about where and how we live. Learning to live more with water may also provide opportunities. We will then use this information to help our communities, infrastructure and natural environment to thrive into the future. There is potential to strengthen iwi partnerships by working together on climate solutions, and for Whakatū Nelson to position itself as a climate knowledge hub.

In low lying coastal areas subject to coastal inundation, sea-level rise generally worsens issues associated with other hazards, for instance, stormwater flooding may become more regular and extensive due to higher sea levels. The collective impact is expected to compromise the capacity of stormwater drains.

These coastal inundation areas are also largely within possible liquefaction areas, and sea-level rise is likely to result in higher groundwater tables in the future. Further investigation is needed to assess whether, and by how much, reduced depth to the water table is likely to increase liquefaction risk for Nelson coastal areas.

Council has an obligation under the Local Government and Official Information and Meetings Act 1987 to include in Land Information Memoranda (LIMs) information identifying natural hazards that are known by the Council, but not apparent from its Resource Management Plan.

A LIM generated for a property will include a notation about any natural hazard known to the Council that may affect the property. LIM notations also advise the reader of further information that is available from the Councils website, including technical reports and mapping.

Recently, Council received new and updated information on liquefaction, fault rupture and slope instability. Council sent a letter to landowners whose properties were identified as being potentially susceptible to liquefaction, fault rupture or slope instability where their property did not have an existing LIM notation, advising them of the new information and the new notation on the LIM for their property.

In late 2021, Council wrote to potentially affected property owners advising of updated river flood mapping. As a result of the updated mapping there are some properties that are no longer affected while others are newly affected. Given this, there will be some changes to the LIM notation of some properties. In late 2020, coastal flood mapping was released and LIM notations are now applied to properties affected by up to 1.5 metres of sea-level rise.

We are seeking your feedback on this phase of Nelson Climate Adaptation from 22 June until 14 August 2022. You can share your views via the online survey.

This is a multiyear project and Council will be coming back to the community to seek feedback on specific adaptation options for different locations around the city.

In the survey please tick the box ‘yes I would like to participate in more in-depth discussions’ if you would like to be involved in future engagement on Nelson Climate Adaptation.

We will ensure that any future events are widely advertised, so you have an opportunity to participate and to share your views.

If you have any questions, you can get in touch by emailing submissions@ncc.govt.nz.