Rotorua Lakes Council admits delay in reporting wastewater leak to regional council

A sign warning the public of the wastewater leak in Ngongotahā. Photo / Andrew Warner

Rotorua Lakes Council blames "human error" for delays in notifying the regional council about a wastewater spill into Lake Rotorua.

A public health warning was issued Tuesday and the council estimated up to 20 cubic metres of wastewater may have reached the lake over three hours.

The council learned of the overflowing maintenance hole, near Arnold St and Waiteti Rd in Ngongotahā, on Monday about 7pm.

Rotorua Lakes Council three waters services manager Eric Cawte said once the overflow was stopped the relevant authorities were "notified immediately", with Toi Te Ora Public Health contacted during the response.

"Contact with [the] regional council was delayed until the following day. This was due to human error and is not usual practice."

He said the overflow was stopped by 7.33pm on Monday, the area around the overflow disinfected and signs installed at 7am on Tuesday.

"Once more information was able to be gathered, a public health warning was issued across [the] council's digital channels as soon as possible."

It did not produce a media release warning of the spill, instead posting updates to its website and Facebook page.

Cawte said the council was comfortable the response had adequately protected the health and safety of the community, but it would use it as an opportunity to improve the notification process with Trility.

On Tuesday, Te Arawa Lakes Trust chief executive Karen Vercoe said she was concerned about the timing of notification to the trust, and would expect "more timely reporting especially to us as the Te Tiriti partner".

Cawte said Te Arawa Lakes Trust – kaitiaki and owners of the lake bed – and hāpu were notified on Tuesday morning before public notification "as per our usual process for after-hours events".

"It is important that, when we are notifying our partners, that we try to provide them with as much detail as possible rather than just a simple alert."

He said it was safe to enter the water on the other side of the lake, but it was "difficult to determine" because of wind and water currents.

"It is unlikely high levels of contamination spread further than 500 metres each side of the spill."

He said test results show the levels of contamination reduced significantly in the first 12 hours.

On Tuesday evening the council said the fault was because of a computer error at the pump station and the council was trying to determine if it was due to a power cut. The computer issue had been addressed and a level sensor for a backup alarm system had been replaced.

The council was asked if it was confident the problem would not happen again.

"We would like to reiterate that, with 80 pump stations, 500 kilometres of sewer main and 8000 manholes there is always a risk [of] a fault," Cawte said.

Te Tatau o Te Arawa chairman and Bay of Plenty regional councillor for Ōkurei Te Taru White said he wanted the district council to act as fast as it could to fix the problem and let people know as soon as possible.

Te Tatau o Te Arawa chairman and Bay of Plenty Regional councillor Te Taru White. Photo / File

"There might have been a bit of a lapse of time in this case."

White said in Māoritanga anything that diminished the quality of the lake was unacceptable as water was sacred and a life-giver.

"There's a history there. I was witness to it. We've had a horror story already – that lake was our rubbish dump.

"Any leakage is not tolerable, but accidents will happen and we [Te Arawa] expect to get notified very quickly, but also for it to be dealt with quickly, and preventions put in place so it doesn't happen again."

He said there was further context of late as the council had found itself, in his opinion, in a "tight spot with the landfill".

White was referring to a district court case in which the council had pleaded guilty to one count of discharging a contaminant - namely stormwater contaminated with leachate – on to or into land in circumstances where it may enter water at its landfill in south Rotorua.

The leachate was described in the case's summary of facts as having levels of bacteria equivalent to raw sewage.

White doubted there would be a rāhui on the lake, but believed the ultimate call may be up to the mana whenua nearest the spill.

On Wednesday, Bay of Plenty Regional Council compliance manager Stephen Mellor said the regional council had begun an investigation into the leak, which would determine its compliance and enforcement actions.

He said the regional council could not comment further until the investigation was completed.

Vercoe was unavailable for comment yesterday.