Proposed changes to drinking water regulations could cost the Dunedin City Council tens of thousands of dollars.
Such a spend would be needed to update software and compliance monitoring, the council has signalled.
It is poised to recommend the national water services authority Taumata Arowai pick up at least some of the bill.
On Thursday, the council is set to discuss its draft submission to the authority about proposed changes to drinking water quality assurance rules for large supplies.
Taumata Arowai has described proposed changes as being aimed at establishing clear, consistent approaches to give water suppliers certainty about what is expected.
Some reporting would be made "easier", rules about chemicals would be standardised and treatment levels would match source water risk, the regulator said in a discussion document.
The proposed rules apply to supplies serving more than 500 people.
The Dunedin City Council has three of those — Dunedin City, Outram and Waikouaiti.
A fourth, West Taieri, serves about 450 people, but the council has also chosen to apply the requirements there, as it includes Dunedin Airport.
In its draft submission, the council said it supported most of the proposed changes.
"The DCC expects improved clarity and consistent implementation of the rules will contribute to improved compliance and — ultimately — to improved drinking water safety."
It also commented on cost implications.
"The DCC estimates the costs of modifying its electronic compliance monitoring and reporting system to address all rule changes covered by this proposal — including minor changes such as revisions to the rule numbering system that are administrative in nature and are unlikely to have a material impact on drinking water safety outcomes for consumers — is likely to be in the tens of thousands of dollars."
Its draft submission recommended Taumata Arowai "considers how it can offset the up-front costs for suppliers".
Taumata Arowai commented on cost implications in its discussion document.
The proposed changes "aim to minimise compliance costs where possible, while ensuring suppliers provide good-quality drinking water".
The authority said there would be some unavoidable "back-office" costs from the changes, as they would require updated or new recording and reporting systems.
Preliminary discussion with two data service providers indicated costs related to reporting changes "could vary from a few thousand to tens of thousands, depending on the number of supplies each supplier operates and the approach the supplier takes to reporting".
