All five Otago councils were identified as non-compliant to varying degrees during a recent Otago Regional Council investigation, but Clutha is the most severely affected - all 11 of its plants, covered by 12 consents, were found to be "significantly" non-compliant.
The full results will be presented to ORC during its regulatory services meeting in Dunedin tomorrow morning.
Contacted by the Otago Daily Times yesterday afternoon, Clutha Mayor Bryan Cadogan issued an apology to residents for the "embarrassing and unacceptable" situation.
"The ... ORC report regarding the unacceptable failings at all our sewerage plants has uncovered a labyrinth of issues and concerns that we are still working through.
"But what is obvious is that the standards the public can rightfully expect have not been upheld and, on behalf of council, I apologise," he said.
The issues first came to light following a resident’s complaint last December.
A subsequent inspection by Clutha staff revealed a range of non-compliance issues at its BioFiltro plants in Lawrence, Owaka, Kaka Point, Sterling and Tapanui.
The extent of the issues led ORC to begin a wider assessment of the region’s facilities, during which all 11 Clutha plants were found to be deficient.
Central Otago and Queenstown Lakes district councils also fared poorly, registering six and two instances of significant non-compliance respectively.
Clutha chief executive Steve Hill said deficiencies in the district ranged from non-compliant discharge sampling results to failure to report and provide records, discharge overflows and lack of maintenance.
Overflows included occasions where "unscreened sewage [was] discharged" into waterways, including "floatables" such as rags and toilet paper, he said.
To address the situation, the council was taking a range of immediate and longer-term actions, and had allocated additional staff.
So far, "just under" $1 million had been allocated to remediation, Mr Hill said.
He would not comment in detail on reasons for the failings, citing a separate internal investigation yet to be completed.
However, Mr Cadogan described the underlying issues as "prolonged and incremental".
It was not clear whether the ORC would initiate punitive proceedings as a result of regional councils’ widespread non-compliance.
ORC regulatory general manager Richard Saunders said he could not comment while investigations continued.
"Any instance of non-compliance is assessed on a case-by-case basis to determine the appropriate enforcement response."
