The Hurunui District Council’s South Ward, including Amberley, has experienced a building boom in recent years, but this is not reflected in the latest provisional Census data.
Census data released earlier this year shows Hurunui’s south ward had a population of 5620 in March 2023, an increase of 410 people from the 2018 Census.
This suggests an increase of 1.53 per cent a year over the last five years, much lower than the yearly average increase for the ward of 2.45 per cent since 2001.
But council chief executive Hamish Dobbie said the council’s own data suggests a much larger population increase.
"We would rate the period 2018 to 2023 as a high growth period. You’ve just got to look at the number of houses being built.
"Maybe when they did the Census, people weren’t in their houses and did it somewhere else.
"There is something that doesn’t add up, or maybe it is right and the population was over estimated in 2018."
Over the last five years, the council has issued 373 consents for new houses in the South Ward, mostly for three or four-bedroom houses.
Dobbie did not believe there were lots of empty houses in Amberley.
If Census data is unreliable, it can complicate council planning, he said.
When the council conducted a representation review ahead of next year’s local government election, it had to rely on 2018 Census data as the 2023 data was not available.
A rapidly rising population formed part of the reasoning behind a proposal to establish a community board for the South Ward.
"We do our own numbers for planning for things like water supply," Dobbie said.
"If we utilised growth numbers that come from the Census, we wouldn’t have water available when it is needed."
A Stats NZ spokesperson said the figures for Hurunui’s south ward compared the 2018 Census with "population estimates and projections".
"Estimated population change for an area comes from estimated natural increase (births minus deaths), plus estimated net migration."
Migration is hard to estimate because there is no single ‘‘authoritative data source’’ to measure migration into and out of an area, the spokesperson said.
"Estimates for June 2023 are provisional and subject to revision," the spokesperson said.
Building consents are useful, but not all consents result in completed houses, there is a lag between consent and occupancy, some are for second homes and some are to replace demolished buildings.
A second release of 2023 Census data is due on October 3, while population estimates will be revised next year.
By David Hill, Local Democracy Reporter
LDR is local body journalism cofunded by RNZ and NZ On Air.
