The Southland District Council will spend up to $23 million upgrading wastewater treatment systems around the district over the next 10 years.
Higher environmental standards required for wastewater treatment and disposal — paired with the need to upgrade ageing infrastructure — means rural Southland's wastewater infrastructure will be a high ticket item for the district council over the next ten years, according to its recently approved long-term plan.
Upgrades are required in Te Anau, Winton, Riversdale and Manapouri, and the council has also allowed for resource consent costs for all schemes that will need new consents during the period, including these four plus Lumsden, Monowai, Otautau, Oban and Tuatapere. The high cost of the upgrades is one of the reasons the council will be going into a first-time deficit for the next five years.
Southland District mayor Gary Tong said the council anticipated the big price tags, which made for "an exceptional amount of funding" paired with other items such as the Around the Mountains Cycle Trail and roading.
"It's putting ourselves in a place where we need to be, really. It is the first time ever that this council's done that, but it's just to catch up and get everything on an even keel."
Wastewater infrastructure is covered mostly through a district-wide targeted rate. Te Anau is the first of those four schemes to be upgraded. Its new, yet controversial, scheme to dispose of treated wastewater next to the Te Anau-Manapouri Airport is currently estimated to cost $14.5 million.
However council staff expect an updated business case to come out for council review by the end of this month. The updated business case will include a review of a more discreet alternative dispersal method, known as sub-surface irrigation. While the council already has the consent to move forward with aerially spraying the treated wastewater onto the so-called Kepler Block next to the airport, the Fiordland community has generally spoken out against it.
SDC general manager for services and assets Matt Russell said staff expected either method to be feasibly completed before the council's current consent to discharge treated wastewater in the Upukerora River expires in 2020.
He said they interrogated the "worst case" schedule so that time pressures didn't influence the decision the council had to make later this spring.
"As an example, elements like treatment plant storage, the preparation of the site, the establishment of the pipeline, all of these elements need to be completed irrespective of the discharge method," he said.
"We are continuing with those elements of the project in a bid to ensure that, from a timeline perspective, we're not hindering ourselves and keep that stuff off critical path."
Wastewater advocacy group Fiordland Sewerage Options has supported the sub-surface alternative, but spokeswoman Ruth Shaw said the group has felt frustrated by the long wait time for the research.
"Our best option now is that we have sub-surface drip irrigation. That is the best option, and that would be a compromise. A good compromise as far as I'm concerned."
The final business case will go to three council committees for review and comment before going to the Southland District Council for a final decision, which is anticipated to occur this spring.