Dispersal field for Queenstown's treated sewage needs $77.6m fix

The council is earmarking $77.6 million to fix a Queenstown wastewater dispersal field that is underperforming, despite being only six years old.

The purpose of the field is to dispose treated effluent into the underlying gravels of the Shotover flood plain - but it has been failing to do the job it was designed to do for years.

Queenstown Lakes District Council infrastructure boss Tony Avery told a meeting of the council's Audit, Finance and Risk committee on Tuesday the council had received an abatement notice from the Otago Regional Council as early as 2021.

Crux understands the regional council issued a further abatement notice in recent months - and has asked for confirmation of this - when there were operational issues with the Shotover Wastewater Treatment Plant itself that exacerbated the problems at the dispersal field.

The dispersal field was commissioned in July 2018, at a cost of $5.3 million, with reports at the time calling its design "innovative" and cost effective - another earlier solution, a low pressure disposal field, would have cost $21 million more.

Mr Avery says the "failure" of the dispersal field is an "ongoing operational issue" that has been "known about for some time".

He says funding has been included in the draft Long Term Plan - due out for community consultation later this month - for a fix, design work for which is underway.

Mr Avery's comments came in response to councillor Niki Gladding querying why the underperformance of the dispersal field had not been reported to the committee in terms of the level of risk it presented to the council.

It is her view the new line in the draft LTP for $77.6 million shows the level of risk has changed, as the situation with the dispersal field and multiple abatement notices have gone from "being solvable to no longer being solvable".

"This has risk across a number of departments as I see it, from finance to strategy to growth planning, and I'd like to see that being managed, and I have not seen that so far."

Councillor Gladding says she has heard talk of the council using a fast-tracked consenting process to address the issue.

"This is significant."

Councillors were presented with an update on the issue at the dispersal field in a workshop in April, but Councillor Gladding says this did not come "proactively" and only happened because she "pushed for it".

Acting council chief executive Michelle Morss attempted to reassure Councillor Gladding in the meeting, saying the situation is being managed by staff across multiple departments in a "disciplined" way.

It is her view her risk team's conclusion issues related to the dispersal field present no change to the council's risk profile is accurate, though she noted what she called Councillor Gladding's "high interest" in it.

"I would suggest that your perceptions around the way this is being managed are not necessarily accurate in this occasion, and I have been having this conversation over the past couple of days because of the concerns you have raised and can very much assure you that the management of this across a number of divisions is actually extremely well coordinated, and that is not something we can always put our hands up to."

However Councillor Gladding replied that while she could "appreciate all of that", it was her view the acting chief executive appeared to be missing "the governance piece" of the puzzle.

"It may be being handled, but we need to see it being handled, is the point, because otherwise it creates concern."

The wastewater disposal field services the Whakatipu Basin communities of Queenstown, Arthurs Point, Frankton, Kelvin Heights, Quail Rise, Shotover Country, Lake Hayes Estate, Lake Hayes, and Arrowtown.

It is located beside the problem-plagued Shotover Wastewater Treatment Plant, currently also being upgraded to boost capacity to cater for growth.

Whakatipu councillor and infrastructure committee chair Gavin Bartlett tells Crux treated wastewater has been ponding at the dispersal field rather than draining away.

"My understanding is that the issue relates to soakage rates...which haven't been able to meet the rates that were assumed in the design of the field.

"Consultants have been engaged to consider options for alternative long-term solutions to meet future demands, also keeping in mind that regulations around disposal of treated wastewater may be subject to change."

He says action has been taken to ensure that excess treated wastewater is contained within the site perimeter.