The West Coast Regional Council has been left with egg on its face in a "potential error" over the way its rates bills have been calculated.
It is being described as a human error and "a fricken embarrassment" by officials, but affected residents may not see a refund until next year.
The issue comes after some ratepayers across the region, including in Greymouth, were shocked last week to open bills with increases of up to 100 percent.
Bills started landing with ratepayers after council in June approved a nearly 17 percent general rates rise in 2023-24.
Instead, the reality was a much higher increase than the 16.9 percent general rates rise - for some.
The other fixed charges incorporated in rates invoices - including for civil defence and the Te Tai o Poutini Plan - also contributed to rises this year.
Risk and Assurance chairperson Frank Dooley said the capital valuation figures used to calculate the rates, in at least the Greymouth area, were incorrect.
"The calculations are wrong."
Dooley said after being notified on Monday, he looked at rate demands from three Greymouth properties and saw the base calculation in each case had been incorrectly done.
"It's a fricken embarrassment … the wrong capital values have been used and it's got to be corrected," he said.
Earlier in the morning, chief executive Darryl Lew issued a statement apologising "for the confusion".
The issue with wrong rates invoices was not just confined to regional council ratepayers in the Grey District.
"It appears that the potential error has occurred across the region and is not limited to Grey District ratepayers."
Lew described the issue as a "potential error" in the way rates invoices were calculated.
"It appears that the confusion is in the way the calculations have been made as part of new QV valuations," he said.
"We are working hard to get to the bottom of this and resolve it."
Asked about the extent of any overcharging, Lew replied it was still being worked through.
"It is not clear to us yet the direction of the potential error," he said.
He also acknowledged a difference between the capital values available on the council website rating base and that on printed invoices people had received. Council was looking into that discrepancy.
Lew said ratepayers who might have been overcharged may be paid back via a remittance or refund when the second rates instalment was due in April-May. In the meantime, ratepayers were encouraged to still pay the first instalment of their invoice now, he said.
A remittance, or refund, would be then made against the second instalment "potentially at a lesser amount".
"I apologise for the inconvenience caused to our ratepayers and ask that they are patient with our staff as we work through these issues."
It was good council had found the "potential error" and it was trying to resolve it, he said.
"Further information will be forthcoming on this matter as we work through the situation."
Dooley said he did not foresee finding a resolution as too major. At this point council would work through line by line to determine the scale of the mistake across the rating base.
"We don't know what we don't know until we do a full audit."
However, Dooley said back-of-house resources at council continued to be a factor.
"We're onto it, we've identified the issue, we just need to work through a resolution … it's just a human error," he said.
Meanwhile, the council was still without a permanent corporate services manager for that area.
Lew said it had been endeavouring to recruit qualified people into varying positions for corporate services.
"It has been challenging to recruit to the West Coast. This is not unique to WCRC, other organisations are also facing difficulties in recruiting professional staff for many years."
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