Kaimai Junction: a stable population with a falling school roll
Kaimai Junction is a rural service town of 4,200 people. At the last census, 22% of residents were aged 65 and over, compared with about 15% nationally, and the median age was 47. The high school roll has fallen from 310 to 240 in eight years, and the maternity unit closed in 2021. Each year about 60 people aged 15-24 leave for Auckland or Hamilton, and about 25 people arrive or return, mostly aged 30-45. Natural increase is now close to zero. The council is choosing between two strategies. Strategy A: zone 40 low-cost sections and fund a childcare centre to attract young families. Strategy B: approve a 30-unit retirement village and a medical hub. Ratepayers are split. The town's only supermarket says its viability depends on keeping at least 3,500 residents within a 10 km radius.
1. Use population concepts to explain how the town's total population can stay about the same while its school roll falls.
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Age structure is the key. A stable total hides a changing composition. Three processes are working at once:
- Net migration by age. About 60 people aged 15-24 leave each year and about 25 arrive, mostly aged 30-45. The leavers are the group who would become parents in the next decade, so every year of loss removes future births as well as present workers.
- Natural increase near zero. With 22% of the population aged 65+ and few women in their 20s and 30s, births roughly equal deaths. A school roll depends on births five to thirteen years earlier, so the fall in the roll is the delayed result of migration decisions made a decade ago.
- Ageing in place. Older residents stay, so the population total holds up even as the number of children falls. Thirty-five fewer high school students out of a population of 4,200 is only 0.8% of the population, which is easily masked by the arrival of 25 adults.
So the town is not shrinking; it is restructuring. The dependency ratio is rising and the child cohort is thinning, which is why services for children close while the total population looks stable.
2. Evaluate which strategy is more likely to keep the school and the supermarket viable.
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Strategy A (young families) targets the cause of the falling roll. It affects the school directly, but slowly: a family arriving now produces a five-year-old in five years and a high school student in thirteen. Forty sections might attract 30-40 households, perhaps 50-70 children at full occupancy, which is the scale needed. The risk is jobs. Cheap sections alone do not hold families; the 15-24 year olds leave because of work and study, and without employment the in-migration will be a one-off, not a trend. The childcare centre helps mainly by making the town workable for the 30-45 age group.
Strategy B (retirement village) does not add to the school roll at all and may even reduce it slightly. But it does support the supermarket and the medical hub: retirees are consumers with steady incomes, and a medical hub serves everyone. It also generates some employment in care work.
Judgement: B is the more reliable short-term fix for service viability and A is the only option that addresses the roll, but A only works combined with employment. The strongest answer is B plus a jobs plan, with A funded only once work is secured. Choose A alone and you may build 40 sections that stay empty.
3. The council assumes low-cost sections will attract young families. What evidence would you collect to test that assumption?
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The assumption links a housing price to a migration decision, and it can be tested rather than assumed. Useful evidence:
- Where recent arrivals came from and why. Interview or survey the 25 people who arrived last year. If most came for a job, a family connection or a lifestyle change, cheap land is not the driver and Strategy A will underperform.
- Why leavers left. Survey the 15-24 age group. If the answer is tertiary study and employment, the town cannot compete on sections alone; it needs work or better transport links.
- National and regional trends. Are young families moving to small towns generally, or is this town an exception? Regional migration data would show whether the plan goes with or against the flow.
- Waitlist evidence. Ask the local housing provider how many families are on a waiting list for affordable rentals in the town. A long list supports the plan; no list undermines it.
- Price comparison. Compare section prices with nearby towns. If Kaimai Junction is already the cheapest, price is clearly not the barrier.
If the evidence shows work is the barrier, the $X on sections would be better spent on employment infrastructure or transport, and the assumption fails.