Part 2: Transport

1.1 The DCC's strategic priorities for transport network infrastructure

The DCC is still guided by its Integrated Transport Strategy (ITS) of 2013. Until recently, the strategic principles between that document and the Government Policy Statement (GPS) were reasonably aligned. Under the new GPS (GPS 2024), the strategic principles are not aligned.

Local Government is reliant on co-funding from NZTA for the transport network. In order to obtain that co-funding its work has to align with the current GPS.

The challenge then lies in aligning with the recent GPS 2024 and the ITS. The two sets of strategic objectives are set side by side below for comparison:

Table 1: Legislative and planning framework impacting Transport

Without an aligned approach to infrastructure management, a 30 year infrastructure strategy will constantly change as the GPS changes because of its intrinsic link to co-funding and the minimization of burden on the ratepayer.

The key strategic priorities for the transport part of this Infrastructure Strategy are drawn from commonalities and agreed Council Zero Carbon goals, the Future Development Strategy (FDS) and subsequent growth and the principles of good asset management.

• Maintaining and renewing existing assets
• Providing travel choices
• Supporting economic productivity
• Resilience - ensuring the ongoing resilience of Dunedin's transport system and key infrastructure
• Growth - planning for and responding to growth.

1.1.1 Safety

There has been a slight downward trend in deaths and serious injuries on the network over recent years, however crash numbers involving death or serious injury (DSI) has not reduced significantly. In fact, these numbers were the highest since 2019. Of particular concern is that vulnerable road users (VRU’s) are over-represented in crash statistics, for example nearly a quarter (24%) of the DSI crashes involve pedestrians. Road factors are reported as being a causal factor in a significant number (10%) of crashes.

Infrastructure interventions to help address this were co-funded through the Low Cost Low Risk work programme. The interventions were typically intersection upgrades or roundabouts to improve intersection driver behaviors (to name but a few). The investment was driven on road classification (which assists in determining risk profile) and death and serious injury statistics. Low Cost Low Risk interventions such as these are no longer co-funded by NZTA, nor are they supported by the Government Policy Statement on Land Transport (GPS). Should interventions such as these be favored by the DCC, they will be at full cost to the ratepayer for at least the next three years.

Figure 1: Map showing vulnerable fatal, serious and minor road user crashes for the period 2017-2021, orange - red being the most intensive crash areas (Source: NZTA, Safer Journeys Risk Assessment Waka Kotahi, MegaMaps RtZ Edition 2)

1.1.2 Resilience

There are ongoing responses to managing resilience in the transport corridor across the city, but significant investment is required. As weather events become more frequent consideration will need to be given to whether assumptions and designs for existing assets need to be reconsidered. As an example, should consideration be given to increasing the design assumptions behind road culverts? Do we need to increase their capacity to accommodate more frequent flooding events in the future?

Through Lifelines, agencies work together to plan alternative routes and develop strategies to respond to weather events and other natural disasters. However, these strategies largely focus on the existing asset, and its capability, not on what the asset should look like in the future.

Dunedin would need significant investment on its routes into and out of the city (both north and south) as it has limited redundancy from a linear infrastructure perspective (as road and rail largely follow one another into, and out of, the city in both directions). The limited alternative routes are constrained in their ability to take heavy vehicles (and indeed, are themselves prone to flooding and slip risk). This is key to the supply of fast-moving imported consumer goods which predominantly come via road from the Port of Lyttleton.

There is limited investment in the 9 Year plan to address resilience issues, the investment through Crown Infrastructure Resilience Programme is primarily around areas such as the Peninsula and South Dunedin. The investment profile is small and is only committed for the 2024-2027 National Land Transport Plan (NLTP).

1.1.3 National Policy Statement for Urban Development

The Dunedin City District Plan controls what people can do on their land and how it can be developed to achieve sustainable management of natural and physical resources. This includes managing the use and development of natural and physical resources, in a way that enables people and communities to provide for their social, economic, and cultural wellbeing and for their health and safety.

The National Policy Statement for Urban Development (NPS-UD) 2020 sets out the objectives and policies for planning for well-functioning urban environments under the Resource Management Act 1991. To support growth in the area, a transport assessment of the infrastructure needs for the identified growth areas has been completed. This has been translated into the Future Development Strategy FDS and informs a $20M investment profile for the next ten years.  Growth assumptions are reviewed regularly, and the investment profile for the following 20 years will be reassessed in 2034.

1.2 The current state of Dunedin's transport network infrastructure

Investment in renewals has been fiscally constrained over the past five years. Subsequently, there is a catch-up element to the renewal of the existing infrastructure.  Design standards for infrastructure such as road culverts are generally to accommodate 1:20 year flood events.

The network for cycling and walking has developed over the past 20 years with separated shared paths from the city either side of the Peninsula and along the one-way pairs (SH1) that now provide an “off road” network.  A gap still remains between Portobello School and Ōtākou  in terms of a shared path (the continuation of the Peninsula Connection). There are no connections between the SH88 shared path and the cycleway on SH1 and no off road opportunities for cyclists/walkers from a network coming in from the south which is Dunedin’s largest commuting population.

Figure 2: Pineapple Rock on the Otago peninsula

1.3 Significant transport infrastructure opportunities, issues and options for Dunedin

1.3.1 Replacing and renewing Dunedin's ageing transport infrastructure

The DCC will increase renewals investment by 29% over the first two years of the 9 Year Plan and it plans to retain that momentum into the remainder of the 9 Year Plan and beyond. The renewals investment is based on asset lifespan and condition rating. This, of course, will rely on continued co-funding from NZTA.  Without this investment, the condition of the network will continue to deteriorate with levels of service reductions, and future work will need more expensive interventions.

In the past the DCC has relied more on heavy maintenance to address asset failures versus an optimal programme of renewals which placed a heavy reliance on operating costs, rather than capital.

1.3.2 Responding to changing needs for transport infrastructure

The DCC is responding to the demand for increased travel options across the city. The DCC will continue to invest in infrastructure to support and enable all transport modes across the city where funding allows, and where co-investment is supported through alignment with the GPS. Cycle infrastructure in the CBD continues to be plagued by "gaps" joining up the network, and one of the challenges for the review of the walking and cycling network (Strategic Walking and Cycling review) is to address this.

Figure 3: Cycle counts

Daily average cycle count past available counters (total annual counts / total available counting days across all counters)

In March 2019, the city established the central city bus hub and in 2020 there was the implementation of a cheaper and simpler fare and card system with the introduction of the Bee card. Both initiatives appear to have encouraged further uptake of public transport with bus patronage steadily increasing in the city.

Between July and September 2023, more than 850,000 passengers took the bus in Dunedin. This was a 31% rise in passenger numbers compared with the same period pre-Covid.

In comparison to last year, Dunedin recorded a 28% increase in public transport use in 2023.

Figure 4: Annual bus patronage

The DCC works with Otago Regional Council (ORC) to provide shelter and facilities to support bus users and bus drivers. This is funded directly from ORC, and maintenance and upkeep of these facilities is managed under the maintenance contract. If changes to the bus services occur, the DCC works with ORC to change these facilities (if needed).

1.3.3 Public health and environmental outcomes

The provision of a safe and reliable transport network supports the use of active transport modes which directly affects public health through reduced road trauma and connected communities that are fit and healthy. It contributes to the DCC’s Zero Carbon goals by providing transport choice across the network.

1.3.4 Resilience to natural hazards

Natural hazards pose a lesser risk when infrastructure networks are resilient. Flooding, drought, catchment fire, landslides, rising groundwater, and liquefaction in the event of an earthquake pose the most significant risks to Dunedin's infrastructure. The DCC is working to improve its understanding of natural hazards and to develop options for resilient infrastructure networks into the future, including route resilience.

Sea level rise, flooding, and storms are predicted to intensify over the next 30 years along with increased slips and erosion, increasing the risk to communities and transport networks. South Dunedin, the most densely populated part of the city, is particularly at risk of sea level rise and rising groundwater levels.

As weather events become more frequent and severe, the network's ability to recover is put under pressure particularly for communities on vulnerable routes with limited alternative access options. Such examples include:

• The coastal community of Aramoana (260 residents) is only accessible via one coastal road prone to coastal erosion and regular flooding during king tides
• Northern coastal roads from Seacliff through to Waikouaiti suffer from land instability (both road and rail) and slips are common
• Flood waters inundating the Taieri plains where there have been significant downpours in the Strath Taieri area
• Strath Taieri area (where alluvial fan flooding can occur)
• Port Otago at Port Chalmers - heavy freight and cruise ship passengers access the Port via State Highway 88. Blueskin Road is the only alternative route; however, it is frequently compromised during severe weather and not suitable for heavy vehicles.

All routes have been subject to unplanned road closure following significant weather events which have cut off communities and compromised freight routes.

Renewing ageing infrastructure in flood-prone and coastal erosion areas will reduce some risks arising from natural hazards; however, it will not solve it.

Alpine Fault Quake Resilience and Lifelines resilience projects will also help to improve the Transport networks’ response to an event.

In 2024, the Lifelines vulnerability and interdependency study identified a range of strategic initiatives to create a more resilient infrastructure network, as follows:

• Continuing design and planning work to identify and prioritise responses to natural hazards in high-risk areas – this includes working with communities to identify plans for when to defend, accommodate, or retreat
• Better understanding routes that provide critical connections, the conditions of these, the pressures, and the level of investment needed to address impacts – this includes identifying priorities for network resilience
• Engaging in local planning processes to avoid infrastructure and development in areas at risk of natural hazards and climate change
• Seeking continuous improvement in network resilience through maintenance, renewals, and ‘low cost/low risk’ investments
• Improving operational responses to events to support quick recovery following disruption to the land transport system
• Shifting to more adaptable ‘scenarios-based’ planning
• Improving personal security for people using the region’s transport system.

1.3.5 Planned increases or decreases in levels of service

The DCC sets levels of service in consultation with its community as part of the 9 Year Plan process. The standards at which the DCC delivers its management and maintenance of the network are a requirement of the Local Government Act 2002. They consist of a service statement, a measure, and a target. The result is transparency for the public and other stakeholders that the network can support lifestyle and business needs, and confidence in the DCC's management of the network.

As part of the 2024/34 9 Year Plan process the DCC reviewed its levels of service. The only change is that the parking levels of service focus on the use of parking in the city, rather than the more subjective approach of residents’ satisfaction.

In our last 10 year plan, the DCC acknowledged that Dunedin’s infrastructure networks including transport services, have been neglected in the past. Over many years there has been insufficient investment in their maintenance and renewals, and as a result, the DCC has found itself in catch up mode, where significant work is needed to ensure reliability of its basic infrastructure.

Since 2021, the DCC has increased its maintenance and renewals spend on these networks, not to increase levels of services, but to maintain existing levels of service. The Transport team will, within is available budget, continually look for ways to ensure maintenance of its levels of service, along with concentrating on delivering a safe network.

1.3.6 Urban Growth Agenda

The 2017-2023 Labour Government developed an Urban Growth Agenda that aimed to remove barriers to the supply of land and infrastructure and make room for cities to grow up and out. It has five interconnected focus areas:

• Infrastructure funding and financing
• Urban planning
• Spatial planning
• Transport pricing
• Legislative reform.

As a result of this Agenda, all councils were required to develop a Future Development Strategy (FDS). The FDS for transport has been developed and forms part of the 9 Year Plan. The growth areas identified have been assessed for the need for transport infrastructure to support the predicted growth. The type of infrastructure identified consists of traffic signals, roundabouts, new and extended footpaths, and kerb build outs (to name but a few). This infrastructure helps support growth by enabling travel options, managing safety, and reducing congestion. However, in light of the GPS 2024, that infrastructure is unlikely to be currently co-funded by NZTA.

1.3.7 Government Policy Statement on Land Transport

The Government has four strategic priorities which GPS (2024) will deliver against:

• Economic Growth and Productivity
• Increased Maintenance and Resilience
• Safety
• Value for Money.

The Economic Growth and Productivity strategic priority is the overarching strategic priority for the direction of this GPS. Increased maintenance and resilience, safety and value for money are all equally weighted and important priorities that collectively support the delivery of a transport system that drives economic growth and productivity.

1.3.8 Zero Carbon 2030 target

In June 2019, DCC declared a climate emergency. The 'Zero Carbon 2030' target seeks to achieve city-wide net carbon neutrality (excluding biogenic methane) by 2030. The transport sector is Dunedin's most significant, and fastest growing, source of emissions. On-road transport generates 56% of transport sector emissions. Cars generate almost half of all on-road emissions. Many more trips are taken by car than by commercial vehicles (e.g. light trucks, SUVs), but petrol (used by most cars) is less carbon intensive than diesel (used by most commercial vehicles).

A further third of emissions is generated by trips taken in light commercial vehicles. Trips by heavy vehicles and buses make up the remainder.

Emissions from this sector are closely linked to urban form, which in turn is greatly influenced by the provision of transport and 3 Waters network infrastructure. Trends suggest that with increasing investment in infrastructure to improve the levels of service for active and public transport modes, there is a slow increase in uptake, and with increasing intensification of urban form, these trends are likely to continue.

Overall, intensification enabled by the 2GP, Dunedin's District Plan, is likely to continue to promote shorter commutes and greater use of public and active modes. However, enabling density in planning frameworks doesn't mean it will happen. Development needs to be attractive and there needs to be supporting services like water and transport networks.

The DCC is also taking account of Zero Carbon targets in its spatial planning for the city, including the need for density close to centres and public transport. The key themes in the Zero Carbon plan to support carbon neutral by 2030 from a transport perspective are:

• Developing convenient and attractive walking and cycling networks and public transport services.
• Boosting travel demand management to support use of active and public transport modes.
• Shifting freight to low emissions.
• Decarbonisation of the Heavy Vehicle fleet.

1.4 The plan to address Dunedin's network infrastructure issues over the next 30 years

In developing the Infrastructure Strategy for the DCC, the focus has shifted to renewal of the existing asset to align with GPS 2024 and subsequent NZTA co-funding. However, regardless of Government policy, asset management and renewals are a known need that is not subject to change as the Government changes. Consistent investment in renewals over the 30 year period will ensure two things, the first that it meets the expectations of the city in terms of provision of existing infrastructure, the second that it ensures the city is not faced with a bow wave of renewals capital in the future associated with deferring asset management driven renewal activities.

The overarching strategic premise of the Infrastructure Strategy is to address deferrals in a way that maintains existing service levels and minimises disruption. Sustainability for the contracting market is also another consideration, and costs have been prepared with market capacity in mind forecasting stepped increases to allow for growth to deliver a sustainable volume of renewals.

The Infrastructure Strategy therefore proposes sustained renewal investment.

The level of investment in transport renewals across the city aims to maintain existing levels of service. It focusses on replacing existing assets based on asset management principles of age and conditions. Overall, in the mid to long term, budgets are set with the aim of retaining an asset management driven approach to renewals based on age and condition.

Sea walls, retaining walls and drainage work programmes continue to be assessed considering changing weather patterns however, significant investment to mitigate the impact from seal level rise in the transport corridor is unlikely.

Long-term investment in the transport network will need to focus on resilience to natural hazards (e.g. St Clair sea wall) and consider efficiency and movement of freight and people on the transport corridor.

Continued investment in transport options (where co-funding allows) will need future consideration, as may alternative forms of public transport to support growth and the growing demand for end-to-end public transport journeys.

The DCC has included other projects in the Regional Land Transport Plan, and as the NLTP has been recently released, it is clear funding for walking, cycling and safety interventions (such as pedestrian crossings, kerb build outs) are not a priority of GPS 2024 and will not be co-funded at least for the next three years. However, given the DCC’s commitment to Zero Carbon 2030, Council has chosen to signal investment in walking and cycling infrastructure in Year 3 of the 9Y plan, in anticipation of co-funding for this type of activity to return in the future.

However, the community expects safety interventions in the transport corridor to support the liveability of their communities. These interventions are part of the 9 Year Plan but will need to be wholly DCC funded. These interventions do not align with GPS 2024. Recognizing the likelihood of the need to catch up on this investment, larger allowances have been made in year 5 of the 9 Year Plan for this activity.

Economic development is another area of focus for the Infrastructure Strategy. Ensuring our networks support supply chains that support and grow our economic activity will be important for the future.

Transport infrastructure connects Dunedin to other regions and countries through state highways, the South Island main trunk railway line, Port of Otago and Dunedin Airport. Ongoing investment in land transport (road and rail) is important to enable the export sector to maintain (if not grow) and reflects the importance of the freight task to gross domestic product.

Port of Otago is New Zealand's second only deep-water port and highest export port (in $/commodity value). Southland export products such as meat and dairy are almost exclusively exported through Port of Otago (and is predominantly transported to Dunedin by rail).

Port of Otago will be moving part of their operation to Mosgiel and is in the process of establishing an inland Port (to the west end of Mosgiel). This inland Port will prove much needed capacity for the Port’s operations. The DCC supports the citing of the inland Port and is working with developers to assess the impact on traffic volume from this location to Port of Otago. It is unlikely that the transport corridor around Mosgiel will see any significant increase in heavy vehicle movement for the first five years of the inland Port’s operations there, or that there will be a reliance on rail transport from Mosgiel to the Port. The DCC will work with developers to establish what impact (if any) the operation has on the transport corridor and will include any recommendations for additional infrastructure in future RLTP’s.

The forestry sector is growing in and around the Otago/Southland area, and approximately 100 log trucks traverse the highways and roads of Dunedin to Port of Otago every day to serve this market. The DCC is currently investigating whether this product could transfer to rail, via an inland port south of the Dunedin area (Clutha District). Mode choice for freight is largely a commercial choice so understanding what interventions local and central government can make in this industry is complex. DCC does however, recognize that Gordon Road (the main street through Mosgiel, and a state highway) plays home to many of these logging trucks passing through from their origin to their destination, and the impact this has on liveability, retail, and amenity.

A transport plan for Mosgiel is due to be completed in 2024-2027. The outcomes of this transport plan are to establish the next level of transport investment required for the Mosgiel area over the next ten years, identifying issues and opportunities in the transport network, and noting that the DCC is already working with other parties to support the citing of Port of Otago’s inland port west of Mosgiel.

1.5 Why is our infrastructure important?

1.5.1 Purpose of the transport network

The role of the transport network is to provide safe access to move people and goods to destinations. To support that the DCC manages the following assets.

• 1,076km of sealed roads
• 681km of unsealed roads
• 983km of footpaths and cycleways
• 251 bridges
• 42km of seawalls
• Shelters 369 (please note these are owned by DCC, but their renewal and maintenance is 100% funded by ORC)
• 8,760 catch pits (chambers/mudtanks) (3% increase from 2021-2031 Long Term Plan)
• 5,780 culverts (pipes)
• Parking management system that ensures the community has access to businesses and services
• Streetlights.

Figure 5: Diagram of transport infrastructure

1.6 How does the DCC assess the condition of transport assets?

The Transport team uses a rolling programme of condition assessments and age profiles to inform renewals decisions. For co-funding from NZTA Waka Kotahi, an Asset Management Plan is required. The level of confidence in the knowledge of the DCC's transport assets is high.

All assets have a finite lifespan, but they differ in terms of their use. Many things influence how an asset performs against that lifespan. Exposure to environmental conditions, different material composition, use (both in weight and frequency) are but a few of the contributors to asset condition. Sometimes assets can be extended beyond their predicted lifespan, but other times those contributors to asset condition will create a situation where the asset needs to be replaced at end of life, or before.

Overall fiscal constraints in previous years have meant DCC has not met its asset management driven targets for renewals. Since 2021, the gap between asset management driven replacement and available funding has been 2021 (-15%), 2022 (-13%) and 2023 (-9%). As a result, renewals values have increased by 29% from the 2022/23 financial year.

Assets are not all installed or renewed at the same time, and, as such, the asset management driven spend on renewals is not linear. Equally, the contributors to asset condition (discussed above) can speed up asset management replacement needs and subsequently change the overall investment profile.

To manage asset needs and fiscal constraints, strategies have been employed to increase the assets’ longevity. In some cases, however, these strategies only last so long. For example, the maximum number of seal layers you can add to a road is six, after that a full rehabilitation should take place. Failing to do that (and adding additional layers) will add to the crown of the road and exacerbate drainage issues. Six percent of the current network has six or more seal layers.

Figure 6: Seal layers

Deferral is a strategy to manage fiscal constraints associated with asset management. This approach is illustrated in our kerb and channel condition rating. A high percentage of this asset is rated poor or very poor in terms of condition so it will take a number of years to address the backlog in their asset renewal.

The higher costs across the construction sector post Covid have compounded the fiscal constraints with asset renewals. Footpath renewals (although flatlined from an asset replacement value) are opening up in cost differential in comparison to previous years (i.e. prices are higher), so renewals values reflect increased costs for this asset renewal.

1.6.1 Summary of transport assets

1.7 How the infrastructure strategy contributes to Dunedin's community outcomes

Investing in Dunedin's transport infrastructure will contribute to achieving the city's community outcomes and the vision of making Dunedin one of the world's great small cities. This table shows how key projects link to Dunedin's community outcomes.

1.8 Where are we now? Dunedin's transport infrastructure

Resilience in the transport network infrastructure is under increasing pressure as many assets are becoming more at risk from flooding, erosion and king tides. Generally, the network has sufficient capacity with congestion only experienced in short morning and afternoon commuter peaks.

In the main urban areas, a small number of key intersections have safety or capacity issues. Mosgiel has capacity and safety issues at the Gordon Road/Gladstone Road intersection, including the rail crossing and the intersection of Quarry Road and SH1, which can cause traffic to back up onto the southern motorway at peak times.

Portobello Road along the Otago Peninsula and State Highway 88 to Port Chalmers have good provision for cycling and walking between suburbs and into the city centre. In the case of Portobello Road, the road does not allow for safe access to the shared path or public transport on the harbour side of the road (in some areas). In some places, the width of the road makes it either very costly or impossible to provide safe crossing points to the harbour shared pathway or locate bus stops appropriately.

The intersection between North Road and Opoho Road has safety, capacity and resilience issues, and the intersection between Great King Street and State Highway 1 remains a safety concern. The bottleneck at the North Road and Opoho Road intersection remains a challenge as it is physically constrained.

Other parts of the network experience congestion for short periods at peak times, but traffic volumes ease quickly, and this is not considered a constraint on future urban development.

Heavy vehicle movements continue to put pressure on road pavements and deterioration of roading assets is being observed. This is particularly evident on roads from the south to the Port and the inner harbour.

Over the past few years investment in renewals has not kept pace with depreciation and if not addressed will begin to impact levels of service, growth opportunities and future economic development.

The detail below presents the deferral of renewals in the past.

Kerb and Channel (network percentage completed)

• 2021/2022 0.8% completed vs target of 1.25%
• 2022/2023 0.7% completed vs target of 1.25%
• 2023/2024 0.7% completed vs target of 1.25%

Resealing (network percentage completed)

• 2021/2022 4.4% completed vs target of 6%
• 2022/2023 6% completed vs target of 6%
• 2023/2024 5.1% completed vs target of 6%

Footpaths (network percentage completed)

• 2021/2022 2.8% completed vs target of 4%
• 2022/2023 3.4% completed vs target of 4%
• 2023/2024 3.3% completed vs target of 4%

Dunedin's transport network is made up of $2.4 billion worth of assets (2024 replacement value). 50% of Dunedin's sealed pavements are aged 60 years or over (theoretical asset life ranges from 60 to 100 years).

Road surfaces in Dunedin have an age range of 9-25 years, and 6% of these surfaces are aged 20 years. 42% of these surfaces reach the end of their asset lifespan in years 10-20. The graphs below illustrate the age profile of various assets across the transport portfolio. These graphs indicate the complexity when planning from a budget perspective for asset renewal and illustrate how budget profiles for asset renewals are very rarely (if ever) linear.

Figure 7: Age profile of sealed pavements

Figure 7: Age profile of sealed road surfaces

Dunedin's roads have been built up over many years overlaying surfaces with a new seal. This has resulted in the crown of the road being higher than the kerb height in areas and reducing the capacity of the road to hold water during heavy rain events, as well as introducing issues for mobility users. The maximum number of seals should be six layers and 6% of the network currently has six or more seal layers with 16.9% facing a last seal (illustrated below).

Figure 8: Number of seal layers

Stormwater assets (kerb and channel, culverts and catch pits) represent 18% of the total value of the asset portfolio. The expected age for kerb and channel is between 60 and 100 years and approximately 31% of the assets are over 60 years (note labelled surface water channels in graph below). Kerb and channel condition ratings show signs of decline with 12% of the network in poor to very poor condition.

Figure 9: Age profile of water channels and kerb & channels

Figure 9: Condition of water channels and kerb & channels

Catch pits (mudtanks) have an expected life of 80 years. 72.6% of total catchpits are over 70 years old. Asset management of catchpits is normally through inspection, and they are graded according to their serviceability. Adequately maintained catchpits would be expected to live well beyond their expected (asset) life.

Figure 10: Age profile of catch pits

The asset life of a culvert is 80 years. 43% of these assets are over 70 years. Culverts are regularly inspected for condition and only a small number of culverts are rated in a poor condition. Culverts, however, are subject to influences outside of the asset more than most. Changes in weather patterns and surrounding vegetation can impact culvert performance significantly.

Figure 11: Age profile of culverts

Dunedin has 249 bridges, 728m2 of retaining walls and 101,969m2 of sea walls. Many of Dunedin's bridges are made of stone, wrought iron and steel with some early examples of reinforced concrete. Many other parts of New Zealand have a large component of timber bridges (which have shorter lifespans). In Dunedin, if bridges are suitably maintained there is no requirement for any major bridge replacements in the next ten years.

Figure 12: Age profile of bridge structures

Most of Dunedin's sea walls are made of stacked rock or stone. They have no estimated replacement date and are expected to last if they are fit for purpose (maintenance of these walls involves restacking the stone when required). The St Clair sea wall has design deficiencies so is regularly monitored and maintained and is currently structurally sound.

Most of Dunedin's retaining walls are masonry walls or concrete slope facings rather than structural retaining walls. A theoretical life of a retaining wall is 80 years,79% of current retaining walls are past their asset life.

Figure 13: Age profile of retaining walls

Dunedin's 989kms of footpath are predominantly made of asphalt (85%), the remaining are concrete, metal and slurry. Asphalt has a life expediency of 25-30 years; slurry has 10 years and concrete has 60 years. 23% of the asphalt footpaths are near the end of their asset life. In terms of condition, a reasonably high proportion of footpaths are in poor to very poor condition. In the past three years, footpaths rated poor or very poor represented 18% of the total footpath asset.

Figure 14: Age profile of footpaths

Figure 14: Condition profile of footpaths

The Smooth Travel Exposure survey (below) illustrates that the roughness of Dunedin's roads is increasing. In comparison to other local authorities, Dunedin performs poorly. Smooth Travel Exposure for urban roads has sat below the target measure for the past 11 years (a Department of Internal Affairs measure).

Figure 15: Percentage of travel on roads smoother than threshold

The graph below outlines renewal spend vs actual spend vs depreciation (in the past). Depreciation acts as an indicator for asset consumption, and it shows consistent and material under-investment in the past.

Figure 16: Depreciation vs renewals

Renewal quantities for the past six years are presented in the graphs below for reseals, footpaths and kerb and channel and show they have consistently been below asset management targets. This has led to a corresponding decline in asset condition and levels of service, and an increase in deferred renewals.

The 2024 Asset Management Plan and this Infrastructure Strategy propose sustained renewal investment. In 2024-27 this represents a 52% cost increase on the NZTA approved programme for 2021-24 and a 29% cost increase on the DCC’s 2021-24 forecasted spend.

1.9 Managing Dunedin's transport infrastructure

Asset renewal across the city continues to evolve in terms of determining the impact changes in the climate have on the existing asset. Dunedin is not alone in developing the capability to determine where weather events are having an impact on asset condition. Asset renewal capability is robust, but the impact climate change has on those assumptions, is still evolving.

Dunedin's public transport (bus) network performs well in terms of patronage compared to New Zealand cities of a similar size, but there have been criticisms by bus users at times about the reliability, frequency, and travel times. Dunedin's cycling network still suffers from gaps linking the city, although longer separated cycleways (shared paths) have been reasonably well catered for in the past ten years.

Several factors are considered when managing Dunedin's transport infrastructure:

• Asset age, condition, and performance
• Changes to population and land use
• Changes to Government Policy Statement on Land Transport
• Climate change
• Maintenance to repair defects and preserve remaining asset life.

The Dunedin Integrated Transport Strategy 2013 is an overarching strategy covering the whole of Dunedin's transport system and is designed to enable the DCC to review its investment priorities and ensure they are relevant to the current and future needs of Dunedin. It identifies and outlines areas of focus developed from several transport challenges and issues that Dunedin faces. The strategy focuses on transport choice whilst maintaining the levels of service for transport corridor users. The corresponding Asset Management Plan determines a condition-based asset renewal programme that sets the level of investment required to maintain the existing transport infrastructure across Dunedin City.

1.10 Renewing and replacing assets

Transport asset risk management is undertaken using a rolling programme of condition assessments to inform renewals decisions.

Condition is the main indicator used to understand if and how transport assets are deteriorating. The DCC's asset management planning is increasingly focused on asset condition coupled with age profiles and risk assessments. From time to time however, fiscal constraints need to be considered in asset renewal strategies.

1.10.1 Principal options and implications of replacing and renewing ageing infrastructure.

The option that the DCC has decided to take in bold.

1.11 Responses to growth or decline in demand

Factors such as population growth, the rate and type of economic growth, the rate of growth in dwellings and where future housing developments occur will have an impact on the demand for infrastructure.

In terms of growth, the 2023 Housing Capacity report states that growth peaked at 1.4% for the year to June 2016 and then dropped to 0.5% for the year to June 2020 (mostly due to COVID restrictions). Recently, population growth is increasing again (between 2022-2023), with a 1.1% increase in 2023 from the previous year. Population is expected to grow at a relatively high rate between 2025 – 2034 before slowing between 2034-2055. However, there is a relatively slow rate of growth between 2024-2027 (short-term). This offers an opportunity to respond to the FDS post 2027, noting most of the FDS related transport infrastructure investments will not be co-funded in the short-term. The dwelling growth strategy is centred around intensification of existing urban areas. The following graph has been extrapolated from the growth and economic significant forecasting assumptions for the 9 year plan 2025-34 .

Figure 17: Dwelling growth

In 2023, primarily to inform the FDS, an update to the 2021 assessment was undertaken. The update considered recent changes to population growth and development trends, and updated the demand for dwellings, supply of development capacity, and the sufficiency of development capacity to meet demand. To respond to this, an infrastructure programme has been developed which indicates the transport requirements to accommodate areas of growth to support a safe, connected transport network providing transport choices. Congestion does need to be considered, and where possible infrastructure has been planned into areas where congestion (through additional dwellings) might occur. DCC cannot provide for infrastructure for the State Highway to support that growth, however DCC will work with Waka Kotahi NZTA to develop any plans that require changes to the State Highway to accommodate growth.

Key constraint areas such as Mosgiel will be investigated further in 2025/2026 through transport modelling, and there is work underway to investigate freight movements in/and around the Mosgiel/Taieri area to support the inland Port on Dukes Road and to support economic development and carbon zero goals.

The changing composition and rate of growth in the economy may impact demand for network infrastructure. For example, the Port of Otago at Port Chalmers is New Zealand's fifth largest port (by commodity value) and a key link in New Zealand's international supply chain as a regional hub for the export of high value products including meat, dairy, timber, fish, horticulture, and other agriculturally based products.

1.11.1 Principal options and implications

1.2 Public Health and environmental outcomes

The transport network provides important public health and safety benefits to the community and delivers transport choice helping contribute to zero carbon (environmental) outcomes. The ability to be able to move around easily across a variety of modes is linked to health, social and economic benefits. A goal of the Integrated Transport Strategy is to increase the percentage of people who walk, cycle, and take public transport to work from 16 percent to 40 percent by 2024. Committing to the goal of increasing transport choices will also contribute to the city's environmental commitments of being net carbon zero by 2030.

Death and serious injuries on the transport corridor contribute negatively to public health outcomes both socially and economically.

An analysis of crash statistics indicates factors which contribute to Dunedin's safety record are;

• Intersections
• Young drivers
• Older drivers
• Pedestrians and cyclists.

Dunedin also has a diverse network ranging from busy urban roads through to quiet rural roads. In some cases, the transition between urban and rural is very abrupt. The central city is also compact and needs to cater for a wide range of user groups, such as cyclists, pedestrians, cars and heavy freight vehicles.

State Highway 1 runs through the University of Otago, Otago Polytechnic and the CBD, State Highway 87 runs through the Mosgiel centre, and State Highway 88 runs through the Ravensbourne and Port Chalmers communities; they all carry a high number of heavy vehicles.

Heavy vehicles also service the CBD and industrial areas such as South Dunedin. This sometimes creates conflict with users of the transport corridor at peak times (whether for school or work). Revising the roading bylaw to determine the best times for heavy vehicle deliveries to these centres is a workstream the DCC's Transport team are undertaking in 2024/25.

Improving network safety is an issue to be addressed through specific safety improvement programmes (where it is cost effective to do so).

Safety interventions undertaken by the transport group include:

• Upgrading infrastructure around schools to calm traffic
• Upgrading pedestrian facilities
• Using fixed safety cameras at intersections and other high-risk areas (where funding is available)
• Implementing a prioritized programme of safety engineering projects.

1.12.1 Principal options and implications for responding to public health and environmental concerns

The option that the DCC has decided to take is shown in bold.

1.13 Resilience to natural hazards

1.13.1 Environmental impacts

Flooding, landslides, drought, catchment fire, rising groundwater, and the risk of liquefaction in the event of an earthquake pose the most significant risks to Dunedin's infrastructure. It is anticipated these risks will increase over time as a result of climate change. Resilience funding from central government has been made available in 2024, however this is specific to areas identified in the application (namely Andersons Bay and Portobello Road).

The biggest issue to Dunedin from an environmental, climate change and natural disaster perspective is its network to the north, south and west. As evidenced in the October 2024 flood event, it is not unusual for all routes to be severed into and out of the city.

1.13.2 Climate Change

Climate change impacts include more extreme rainfall events, causing increased frequency and severity of flood events. Rising groundwater as a result of sea level rise in low-lying areas is the one of the most significant risks facing Dunedin from climate change. High groundwater and increased rainfall can contribute to asset renewal acceleration, and recent examples on accelerated asset failure (water levels have reduced reseal longevity) from flood events, can be seen as a result of Cyclone Gabrielle.

1.13.3 Earthquakes

Seismic activity can cause widespread damage to network infrastructure. Destruction of critical built infrastructure can impact the transport network. Dunedin has several areas with moderate to high likelihood of liquefaction in an earthquake. Seismic activity could also cause isolation across the transport network if certain areas are cut off due to rubble, slips, liquefaction, or land displacement. frequently

Figure 18: Akatore fault MMI intensity classes

Estimated ground shaking expressed in MMI intensity classes for a magnitude 7 earthquake centres on the Akatore fault. Intensities of VII and VIII would be expected to be in coastal sectors of much of the Dunedin district and would be likely to generate liquefaction in susceptible locations.

1.13.4 Building resilience to natural hazards

The Peninsula Connection project is an example of building a more resilient asset by raising the road to allow for predicted sea level rise while widening the transport corridor (for safety purposes) and creating a shared path (for mode choice purposes). The remaining section of this corridor between Portobello and Ōtākou remains at risk from a resilience perspective, and the section of corridor at Fisheries Wharf before Ōtākou is frequently flooded in weather events and high tides.

As part of building resilience to natural hazards, DCC (as part of the Climate Adaptation work) will be investigating whether existing assets (such as road culverts) need to be reconsidered in terms of their design standards. Building culverts for 1:70 year events, and raising the transport corridor (where it is vulnerable to sea level rise) are expensive responses to adaptation. However, over the next three years consideration will need to be given to the existing infrastructure and its resilience to the increasing number of events and their increased severity.

Planning is underway to look at the resilience of the transport network in the case of a seismic event, specifically around the supply chain and getting goods to and from Dunedin. Planning is also underway for any Alpine Fault activity. In a seismic event involving the Alpine Fault, Dunedin may be the least affected so may have to become a recovery hub for the lower South Island.

The GPS 2024 response to resilience is in addressing the existing maintenance and renewals task. This is one of the GPS sites as “increased maintenance and resilience”. That resilience is achieved through increased expenditure on potholes, resealing and rehabilitation. Apart from the small about of funding discussed earlier ($1.5M over 2024-2027 NLTP) there is no co-funding for raising the height of the transport corridor or increasing the size of road culverts etc. A more strategic response to this will be considered as part of the climate adaptation strategy underway.

Central Government response to Cyclone Gabrielle and responding the communities at risk in terms of exposure to natural hazards will determine the strategic approach taken over the next ten years for the transport network.

1.13.5 Principal options and implications for building resilience to natural hazards

The option that the DCC has decided to take is shown in bold.

1.14 Planned increase or decrease in levels of service

The priority service levels for the transport network are:

• Asset Management - the transport network is renewed in accordance with asset age and condition.
• Cost efficiency - The relative costs and efficiency of the network compared with other networks.
• Economic Productivity – The network supports ongoing economic productivity in the city including supporting economic productivity of the supply chain to and from other regions.

There are projects in the capital programme that aim to respond to levels of service across the city in light of the hospital rebuild and growth in the city, detailed below:

• Harbour arterial improvements - the harbour arterial route would run along Wharf St and Thomas Burns St to provide an alternative route bypassing the city centre, avoiding the new hospital during and after construction
• Park and Ride facilities at Mosgiel and Burnside - parking areas, where people can leave their car and catch a city-bound express bus service
• Central city parking management - implementation of a plan to improve the parking experience, wayfinding of parking, and a review of the pricing structure of parking, to encourage better parking options for the CBD which will contribute to economic development
• Bus priority measures and safety improvements - providing infrastructure to prioritise buses and safety improvements for pedestrians in and around the CBD
• The Tunnels Trail – cycleway connection between Mosgiel and Dunedin.
• Cycling and Walking infrastructure that assists in meeting Zero Carbon goals and provides greater network connectivity for this mode across the City.

1.14.1 Principal options and implications for increasing or decreasing levels of service

The option that the DCC has decided to take is shown in bold.

There is only one change to existing service levels reflected in the parking metric below.

1.15 What we need to do - Dunedin's most likely transport infrastructure scenario and approach to delivering new capital and renewals

The Infrastructure Strategy is closely linked to the Financial Strategy. The Financial Strategy considers affordability for ratepayers and the DCC as a whole. The DCC has attempted to balance the competing tensions of affordability, maintaining assets and investing for the future, while addressing the financial challenges of increasing costs, delivering large capital projects and increasing network renewals. The Financial Strategy provides strategic financial limits for rates and debt and discusses other funding sources.

1.16 Major projects and decisions

The Future Development Strategy (FDS) capital is split separately to remaining capital for the purposes of this document.

1.17 Approach to delivering the new capital and renewals

The DCC plans to maintain internal capacity and reduce external (consultant) capacity to deliver the capital programme

• Using existing staff to project manage new capital projects and reducing external consultant assistance
• Continuing to deliver the renewals programme internally including continuing to grow capability of internal delivery i.e. engineers' representative and engineers to the contract
• Continuing to seek opportunities to package works with other large organisations such as Waka Kotahi and ORC to enjoy economies of scale and minimise community impact.

Figure 19: Transport capital expenditure by type 2025-2034

Figure 20: Projected Transport capital renewal expenditure by type in 5 year bands for the 1 to 30 year period

Figure 21: Projected Transport capital capital renewal and operating expenditure in 5 year bands for the 11 to 30 year period.

1.18 The 30 year plan for transport infrastructure

The DCC's Transport team will remain focused on maintaining the transport corridor to the appropriate levels of service. Smaller safety interventions will continue as long as Low Cost Low Risk funding is maintained. Council has considered funding the strategic walking and cycling network and has agreed to add capital into Year 3 of the 9Y plan. As these projects are planned, the co-funding environment may change. This will become clearer at the time of the next 10Y plan.

Delivering the planned renewal and new capital programme is achievable within the capacity of existing external contractors.

Longer term investments will require further planning and investigation, taking into account climate goals, economic influences and the geo-political world situation. A focus towards a whole of network outcome (i.e. getting through Dunedin, through Mosgiel, to the Port of Otago) will need to be the priority for the next ten years whilst maintaining safety, considering resilience, and supporting economic development.