Infometrics senior economist Nick Brunsdon says the population of cities and towns are constantly changing in response to shifting age structures, fluctuations in net migration, the economic prospects of key industries, and intangible attractiveness.
To understand how each of these areas are projected to grow, Infometrics used Stats NZ’s 2022 subnational population projections for Statistical Area 2 (SA2) areas – a useful resource which reflects historical trends, demographic drivers, and limited input from territorial authorities.
Hamilton to overtake Wellington
Brunsdon says almost all areas are expected to see growth in population over the next few decades, but the pace varies.
Among the seven major urban centres, the population rankings are relatively stable, reflecting the inertia of large populations and fairly widespread growth.
Dunedin is a notable exception to this widespread growth, projected to grow a total of 6% between 2018 and 2048, lagging the other major urbans with between 10% and 34% growth.
Auckland urban area will remain in a class of its own, with its 21% growth adding 297,100 people by 2048 – the equivalent of adding Hamilton and Lower Hutt combined, and Christchurch will remain the second largest major urban area.
But the bronze medal seems likely to shift, Brunsdon says. “At present, Wellington is New Zealand’s third largest major urban area. Wellington’s projected growth of 11% by 2048 translates to a solid 23,900 gain in population, but this increase will still see it knocked off the perch and out of medal contention.”
Hamilton is set to steal the bronze crown, with the area projected to grow 34%, adding 60,600 residents, and moving into third place in 2048.
Rotorua, Nelson and Invercargill leapfrogged
Focusing on large urban areas, Brunsdon sees more leapfrogging of rankings. The Rotorua urban area (including Ngongotaha) is projected to grow by a modest 3%, which would see it overtaken by the urban area of Porirua, growing 14% and Hibiscus Coast in northern Auckland, growing 10%. Strong growth of 12% projected for Hastings would see it overtake Nelson at 5%.
Among the medium urban areas, he sees some bigger ranking shifts than the large or major urban areas. Most notable shifts come with Pukekohe growing 43% and Rolleston 41%, which both overtake Blenheim 7%, Paraparaumu 6% and Timaru 2% in the rankings.
Rolleston remains town of the future, not city
Rolleston has been the fastest growing urban area, expanding by 17 times its original size between 1996 and 2022. Rolleston’s growth has been aided along the way by exodus from Christchurch after the 2010-11 earthquakes and to the work from home phenomenon during the Covid-19 pandemic.
By 2048, the town’s population is projected to total 39,400, likely graduating from a small urban area to a medium urban area, and overtaking Gisborne in the process. However, this growth still wouldn’t qualify Rolleston as a city – that takes a population of 50,000 within a contiguous urban area. Rolleston’s main prospect for city status will be expansion to the east.
Could Rollicoln be New Zealand’s next city?
To the east of Rolleston is Lincoln, another fast-growing Selwyn District town, with less than five kilometres of rurally-zoned land in-between. Most of the land is used for agriculture and lifestyle blocks, a status maintained by Selwyn District Plan and backed up by National Policy Statement for Highly Productive Land (NPS-HPL).
However, over decades, these rules can change, Brunsdon says. “If the rural buffer area were to be developed, then the combined Rolleston-Lincoln urban area would have a population of 53,900 in 2048, likely qualifying as a city. Rollincoln (name to be confirmed) would overtake the Whanganui, Upper Hutt, Invercargill, and Nelson urban areas for a place in the top 20.”
Ageing population slows outlook
New Zealand’s population growth is slowing overall, with an annual average increase of 1.3% between 2000 and 2022, easing to a projected 0.7% between 2022 and 2048.
The population growth slowdown is driven by the ageing population, with a strongly rising number of deaths catching up with modestly growing births. The difference between births and deaths, termed natural increase, is a key driver of population growth.
As natural increase eases, net migration becomes increasingly important to prevent population decline.
Given the projected slowdown in national population growth, it is noteworthy that none of the major, large, or medium urban areas are projected to experience population declines between 2022 and 2048, although several face near-negligible growth. Brunsdon says.
The next step down in Stats NZ’s urban-rural area classification is the 146 small urban areas, ranging from Kaitaia to Bluff. Stats NZ projects that 26 of these centres will experience an outright decline in their population between 2022 and 2048.