South Wairarapa District Council wants a detailed breakdown from Wellington Water showing how much ratepayers have been overcharged for projects and services.
The request was made by deputy mayor Melissa Sadler-Futter at an extraordinary Wellington Water Committee on Monday.
She said each of the shareholding councils deserved a report detailing any potential overspend after reports commissioned by Wellington Water showed its unplanned maintenance spending was far higher than four other comparative councils, and that it had not managed contractors well and had poor financial oversight.
But Wellington Water chief executive Pat Dougherty would not commit to the request, instead suggesting a high-level discussion could take place with each of the six shareholding councils about "the current situation and where we think we are getting value for money and where we have suspicions".
He said if Wellington Water committed to doing a "historical review and detailed reports on what has gone on" for each council, that he "may as well just turn the lights off and not do anything for the next three months" because of the workload that would entail.
He said it was also unclear what the market rates for the region's jobs would have been without going out for tender on similar work.
His "off-the-cuff opinion" was that South Wairarapa District Council was "probably getting the best deal of any of the councils in terms of value for money".
Sadler-Futter pushed back on this and said there was already an indication in South Wairarapa that ratepayers were paying more than they should for water projects and services.
"Before a job is put to market, we already have an indication in South Wairarapa that several of our major jobs, if put to local contractors, could be delivered significantly cheaper than through Wellington Water," she said.
She said her council's trust in Wellington Water was "broken" and that South Wairarapa ratepayers needed to know "that we are spending their money in the best possible way and getting value for money for them".
"At this point, I certainly can't put my hand on my heart and say that we are."
Ros Connelly, who chaired the committee meeting, requested Dougherty come back to the committee on Friday with an idea on how to strike a balance between satisfying councils and ratepayers with detailed information "without being onerously burdensome on the organisation".
"If you can, have a think about what kind of council-by-council analysis would be appropriate to assure our ratepayers and assure the [councils] that their services have been delivered for a market value or what the quantification of an overcharge might have been."
A press release from Wellington Water last week said an independent review had found that in most cases, "we are consistently more expensive than other comparable councils, particularly for drinking water and wastewater assets".
"These higher costs are likely to be a symptom of our contractual set up with suppliers and our lack of oversight, assurance and financial controls and processes.
"It is now abundantly obvious that we have not been delivering value for money for our shareholding councils. This is as unacceptable to the board, as it is to councils and ratepayers.
"It's important to note that these issues are the same ones that staff and some of our councils have been raising for a while now. We apologise for not listening previously. We are listening now and acting.
"We unreservedly apologise to our shareholding councils and the ratepayers of the Wellington region for these issues. Everyone expects and deserves better."
While these investigations were underway, Wellington Water had already implemented some improvements including a reset of its contractual set-up.
Wellington Water's shareholding councils Wellington City, Greater Wellington, Porirua, Hutt City, Upper Hutt and South Wairarapa make up the Wellington Water Committee.
The committee will meet again on Friday.
LDR is local body journalism co-funded by RNZ and NZ On Air.