Planes at risk of bird strike from wastewater plant

A problematic wastewater treatment plant in Queenstown has got another issue — the threat of bird strike.

At a workshop this week, Queenstown Lakes District Council (QLDC) councillors were provided with an update on the organisation’s ongoing response to issues with the performance of the disposal field at the Shotover wastewater treatment plant.

One of the issues raised was the increase in waterfowl landing in the disposal field, which is a few hundred metres from the Queenstown Airport’s runway — leading to potential bird strike.

Queenstown Airport chief operating officer Todd Grace said he was aware of the concerns.

"Wildlife management is an ongoing safety priority for airports and airlines globally, and always has been.

"Queenstown Airport has a comprehensive wildlife management plan, particularly focused on birds, and we take an active management approach in this regard."

Mr Grace said it had been working with a local consultant ecologist who had expertise in the patterns and behaviours of birds in the region and in the areas near the airfield, including the Shotover Delta.

"Most airfields have species that are resident or migratory, so we closely observe to understand the behaviour and activity of birds and we adapt our response and mitigation activity seasonally."

There were a "range of tactics" to manage the risks associated with birds and bird strike, including bird-scaring, such as light flashes and sound to disperse and deter birds.

"Before each flight, our airport emergency services team completes airfield checks. We also actively share knowledge across the airport community, which enables us to manage risk in real time.

"Ponding water is attractive to birds, so leads to an increased risk.

"The risk associated with the ponding at the Shotover wastewater treatment plant has been highlighted to the council, as the owner of the treatment plant.”

In June last year, a Virgin Australia Boeing 737 diverted to Invercargill after a suspected bird strike when it left Queenstown Airport.

The incident occurred less than a month after an Air New Zealand flight from Queenstown to Christchurch failed to take off twice after a suspected bird strike and "unrelated warning light".

Queenstown Lakes District Mayor Glyn Lewers said it did not surprise him bird strike was an issue.

"If you have a look at the history of the wastewater treatment facility on the delta, in the early 2010s, the removal of the oxidation ponds and standing water was one of the aims and outcomes to try and remove the attractiveness of the delta to birds.

"That's always been the end goal from a strategic point of view for the council."

The Otago Regional Council has taken the QLDC to the Environment Court for an enforcement order due to consent breaches at the disposal field, which included surface ponding of wastewater and the discharge of effluent outside the consented disposal field area.

Council property and infrastructure general manager Tony Avery said the treatment of wastewater at the plant remained effective.

The Shotover wastewater treatment plant "continues to produce highly treated water at the end of multiple processes which are all working well”, he said.

"The plant’s performance is monitored daily, and results from both on-site monitoring and external laboratory tests demonstrate that the treatment standard is consistent with the plant’s resource consent conditions."

Mr Avery said the disposal field was separate to the treatment plant and was not relied on as part of the wastewater treatment process.

"This means that water flowing into the disposal field is treated to a standard appropriate for the downstream receiving environment, in this case the Shotover and Kawarau rivers.”

The council will host a media standup on Wednesday "to provide a detailed update on its proposed next steps".