A formal apology has been issued by the Tauranga City Council for failing to decommission the sludge pond at the Te Maunga sewerage treatment works.

Bitterness over the failure to decommission the pond by September 2012 has spilled over in a letter supported by the city's Maori tribes to yesterday's meeting of the wastewater management committee.

Tangata whenua representatives on the committee criticised the lack of action to address their various concerns.

The letter prepared by Tama Hovell (Nga Potiki) said the most appropriate course of action was to review the consents.


Although the biosolids plan was necessary to progress decommissioning the pond, it was not accepted as a substitute for the need to review the consents, he said.

"It does not include any specific measures or actions to understand and mitigate the cultural effects."

Mr Hovell said tangata whenua committee representatives were concerned at the widespread perception they were responsible for the breach and supported the biosolids plan as a substitute for the review of consents. "This is not the case."

Unless the council committed to addressing the cultural issues, the Maori representatives would withdraw their support for the biosolids plan and possibly stop participating in the committee.

Cultural concerns included seepage entering Rangataua Bay. Seepage has spiked to levels close to the maximum allowable after the dredging of sludge pierced the naturally formed crust that normally held back much of the seepage.

Council's chief executive Garry Poole apologised that the action the council had agreed to undertake did not happen.

He assured tangata whenua members that the council understood the level of frustration and gave an undertaking it "would not drop the ball in the future".

Mr Poole said all staff were committed to delivering on the undertaking. However, because the issues in the letter were so significant, he asked for more time to consider the issue.

The committee agreed that decisions on issues raised by its Maori members would be made at a meeting on July 21, preceded by a council briefing on July 11. It brought forward the date for the next committee meeting by nearly six weeks.

Te Maunga Wastewater Treatment Works plans:

• Sludge dewatering and treatment: $8.4 million (2015-18)
• Conversion of ponds to wetlands: $5.87 million (2017-20)
• Proposed changes to future budgets: $9.8 million (mostly spent 2017-18)