Growth in transport demand is tied to population growth. A growing population will mean an increased number of trips to access employment, services and amenities. There will also be an increase in the number of freight and business trips required to service the increasing population.
By 2045, we expect another 1.2 million people to live in New Zealand. This increase will not be evenly spread across our country. Much of this growth will be in the Upper North Island, with 60 percent occurring in Auckland.
Auckland’s growth projection over the next 30 years will place considerable pressure on an already congested road network, and there will be demand for transport infrastructure to service new houses in whole new communities. Achieving an effective and efficient transport system for Auckland is central to improving the city’s contribution to the national economy.
In contrast to Auckland and other growing urban areas, some areas of New Zealand are forecast to experience slow, low or negative population growth. By 2043, 25 of New Zealand’s 67 territorial authorities are projected to have fewer residents than they did in 2013. Regions projecting decreases are primarily rural areas that do not contain a main urban centre. Rotorua, Whanganui and Hutt City are less common examples of major urban centres that are forecast to experience a declining population.
In these areas, the land transport system is likely to play an even more critical role in supporting the economic and social well-being of people, business and communities. But there will be challenges. A declining population means a reducing rates base, making it more difficult for regions to pay their ‘local share’ of necessary transport investment. At the same time, the nature of transport demand in these areas is likely to shift, particularly as local populations age and the shape of local economies evolves. We have an important role to play in understanding the changing nature of transport demand in these areas, and ensuring that the land transport system can respond appropriately.
New Zealand’s population is also ageing due to declining birth rates and better health care, leading to people living longer lives. The median age is projected to increase from 32.8 years in 1996 to 42.7 years in 2043. Again, this increase will not be distributed evenly.
In a number of territorial authorities the percentage of population aged over 65 is projected to be over 35% by 2043. These include Kāpiti Coast, Thames–Coromandel, Horowhenua, Tasman and Central Hawke’s Bay. Conversely, the percentage of the population over 65 in some of our larger centres including Auckland, Hamilton and Wellington is projected to remain below 20 percent.
An ageing population is likely to result in more households on fixed incomes. Over time this may impact on some councils’ ability to raise revenue required to maintain infrastructure and services, particularly in areas where an ageing population is forecast to coincide with an overall decrease in population. Councils will need to continue to work to manage the impacts of de-population and aging populations over the medium to long term.
Our research tells us that there is a significant decrease in overall travel at age 65 as travel to work declines (both in terms of time spent travelling and kilometres travelled). There is a further sharp decrease in overall travel (time and distance) for those aged over 75. Many of the communities experiencing an ageing population are within small territorial authorities with limited scope for alternative transport services.
There are trends that might be expected to change the current travel patterns of those age groups over 65. With the population remaining healthier for longer, there is a growing number of people in the 65-74 age bracket who are choosing to continue working. The arrival of new, affordable and more flexible mobility services (such as autonomous vehicles) could also result in an increase in travel demand for those older age groups.
The economy is both shaped by, and a shaper of, our transport system. Economic fluctuations impact wages, consumer demand, and the prices of raw materials. Higher income growth usually signals higher consumer spending, leading to increased business spending which results in increased demand for goods and services. This, in turn, increases demands on the transport system. Equally, reductions in the performance of the transport system can impact on the efficiency with which businesses are able to bring goods and services to market.
New Zealand’s economic performance is dominated by the increasing contribution of the service sector (particularly business and financial services). The service sector accounted for around 63 percent of GDP in 2013. This is forecast to continue to grow.
In geographic terms, the service sector is closely tied to the main urban areas, and it is these areas that are expected to perform most strongly in terms of GDP growth over the coming decades. In comparison, growth in mining, manufacturing and primary industries is currently flat and is forecast to remain so.
Current economic growth is being driven by historically high levels of immigration (and corresponding lower emigration rates) and strong tourist numbers. Both of these trends are forecast to continue.
In relation to immigration, more people create a need for more housing and a demand for more and better services. As a result, the majority of economic growth is currently in the construction industry (including the Christchurch rebuild) and the businesses that service this sector. Because immigrants tend to be drawn to the larger urban centres, particularly Auckland, economic growth (in the short term at least) is expected to be focused in these areas. Growth in employment trips, business trips and freight movement is therefore expected to be strongest in these areas.
Tourism is also forecast to grow strongly over the short to medium term. International visitor numbers are forecast to increase from 3.1 million (2015) to 4.5 million (2022). The tourism sector has very direct links to transport demand due to the requirement to move people to and from key entry points and between the major visitor centres and attractions. This will create increased demand on networks within and between the main tourist centres such as Queenstown, Rotorua, and the key overseas entry points of Auckland and Christchurch.
We have seen a shift in how tourists get around as well as increases in numbers. More tourists are choosing to drive themselves, and when they do so, they are using both the state highway and many local roads.
National and regional initiatives to create or highlight a wider range of tourism experiences to spread the visits spatially and more evenly across seasons also influence tourist flows and economic activity. There are implications for how the road network is funded as these trends continue, and demand increases.
Looking at the shape of our economy, exports contribute around 30 percent of New Zealand’s GDP, driven largely by the production and export of primary commodities. Ensuring efficient access to our key import and export ports is critical to support export trade and the wider economy.
Globally there is a trend of using larger ships to move international freight. That trend is emerging in New Zealand and is expected to continue, potentially changing patterns of port use around the country as import/export freight functions (particularly containerised freight) are consolidated in fewer ports.
The impact that this trend will have on the freight system is that some types of export freight will need to move longer distances and concentrate on fewer destinations, namely larger consolidation centres and major container ports.
The majority of imports come into the country via the three northern most ports. This is expected to continue given these ports are closest to our trading partners, while our largest domestic markets are also in the upper North Island.
In provincial areas where primary industry makes up a large proportion of the economy, economic performance will continue to be closely tied to international commodity prices. While these regions can be expected to experience improvements in economic performance as commodity prices rise, the overall shift in the economy towards the service sector will continue.
Large areas of New Zealand are forecast to experience flat or negative population growth (often reflecting the modest economic performance of these areas). While this is likely to result in modest (if any) growth in travel demand, transport investment will still have a significant role to play in supporting efforts to improve the economic performance of these areas.
We are on the verge of a major paradigm shift in transport technology. New digital tools and participants in the transport system create new interactions and connections between all parts of the transport system. They realise new opportunities for transport and mobility services, and new tools for managing and regulating the system and getting the most out of it. There is a real opportunity to leverage emerging technologies to help address some of our biggest transport challenges and significantly improve the performance of the transport system for customers.
We have already seen that relatively small scale initiatives, such as improved traffic light phasing and ramp metering, have led to measurable improvements in traffic flows, for example on the Auckland network. Other initiatives, such as integrated ticketing, the greater use of Global Positioning Systems and smartphones are improving customer access to real-time travel information.
Looking ahead, emerging technologies will influence the transport system in ways that we cannot imagine and at a scale and pace that is difficult to predict. Technology presents both challenges and opportunities.
There are a number of disruptive trends for transport that offer significant potential advances, as follows:
Our natural and physical environment directly influences the accessibility and availability of our transport system. Our natural and physical environment is also a major attraction for our international guests, and we need to understand that our transport system has impacts on that environment. New Zealanders and visitors expect a transport experience that is safe and reliable and increasingly resilient to hazards. They also expect that the impacts of the transport system on our environment will be mitigated and managed. Meeting these expectations as our physical environment continues to experience disruption related to climate change or other natural phenomena will present many challenges.
Most New Zealanders live no more than a few kilometres from the coast. Houses, roads and other infrastructure connecting communities have been built in coastal areas with an understanding of the reach of the tides and the recognition that storms will occasionally combine with high tides to cause flooding. With rising seas, tides, waves and storm surges will reach further inland than previously. This will cause more frequent and extensive flooding. Along some coasts, erosion will increase and shorelines will recede.
The extent of the sea level rise in the long term will vary depending on how successful the world is at reducing greenhouse gas emissions. What is clear is that action taken to reduce greenhouse gas emissions will make little difference to the rate of sea level rise for several decades. We are locked in to a sea level rise of approximately 20 centimetres by 2040. Beyond that the sea level rise is difficult to predict and could be in the range of 40-75 centimetres by 2100 depending on how much greenhouse gas emissions might reduce by.
There has been some analysis (Figure 03) looking at how different areas of New Zealand might be impacted by different levels of sea level rise. This analysis is not complete, but does give some indication of the scale of potential impacts.
The vulnerability of different coastal areas to rising seas depends on many factors. Height above sea level is one obvious factor, but it is not the only one. The shape of the coastline, the topography of the land and the seabed, proximity to the sea, the presence of barriers such as sand dunes, and other local characteristics will affect what happens in different coastal areas. It can therefore be difficult to predict which locations are most vulnerable.
In addition to sea level rise, the warming climate will also influence weather patterns in coming decades. As the atmosphere warms, it can hold more moisture – about 7 percent for every 1°C increase in temperature. As the climate changes, both the distribution of rainfall across New Zealand and its intensity are likely to change. Rainfall is projected to increase in the west of both islands and in the south of the South Island. Northland and eastern regions of both islands are projected to become drier. It is also projected that heavy downpours will become more extreme.
Increases in the amount and intensity of rainfall in some catchments raise the risk of river flooding. Areas close to river mouths can experience heightened flows coinciding with the sea pushing its way upriver at high tide. As high tides become higher because of sea level rise, such floods will become more likely.
The duration and intensity of winds drives the power of waves. As circulation patterns in the atmosphere change, westerly winds will become more prolonged and intense, especially in winter. Increased winds will lead to larger waves breaking on the shores of the west coasts of both islands.
As the atmosphere warms, storm patterns are also likely to change. The impact of storm surges will be increased by sea level rise. It is projected that cyclones that form south of New Zealand in winter will become more intense, leading to stronger winds and larger waves on shores exposed to the south. It is also projected that the intensity of cyclones elsewhere in the country will decrease.
We are already seeing increasing pressure on the transport system from shifting weather patterns and trends related to climate change. The trend for increasing expenditure on emergency maintenance and repair work is expected to continue.
We need to increase the ability of the transport system to adapt to the adverse impacts of climate change and foster climate resilience. We need to focus on ensuring the resilience, and quickly restoring access to the transport system, in the face of unplanned events. These two dimensions – increasing the robustness of the transport system and decreasing the recovery time when things go wrong – are equally important. Both depend on having a clear understanding of those locations that are most vulnerable and then executing a plan to mitigate the risk.
Transport also has a role to play in mitigating global temperature rise and supporting public health by reducing emissions. The major contributors will be: