Wanaka's $21 million wastewater treatment facility will be brought back on line today several days after mechanical issues resulted in a two-tonne escape of treated solid waste, forcing the plant to close.
Project Pure began its commissioning phase in November and was shut last Saturday after mechanical malfunctions resulted in an escape of treated sewage and wastewater into the plant's dispersal fields.
The Queenstown Lakes District Council took the plant offline and redirected wastewater to the Albert Town and Ballantyne Rd oxidation ponds after initial fears the treated sludge would invade neighbouring properties.
QLDC wastewater project manager Martin O'Malley said several mechanical breakdowns were to blame.
The plant will be brought back to 25% of its operating capacity, by tomorrow, and would be fully operational, by February 9, he said.
He estimated about two tonnes of treated solids had escaped from the system into three paddocks used as dispersal fields, an area of about 4000sq m.
The sludge would be scraped up and run back through the treatment plant, Mr O'Malley said.
Under the terms of an Otago Regional Council resource consent to disperse treated wastewater, Project Pure is allowed to discharge solids to the dispersal fields - during the course of a year.
Mr O'Malley said the sizeable "one-off" discharge, had not exceeded the terms of Project Pure's consent, but had used a "considerable" portion of its allowable volume.
ORC resource management director Dr Selva Selvarajah could not be contacted, yesterday.
While the malfunction was surprising, it was not totally unexpected, Mr O'Malley saidThe commissioning process was a testing period where the plant was run at optimum levels.
It also coincided with an influx of visitors to the region and an associated rise in operating capacity, he said.
The problems had been compounded by a difficulty in sourcing mechanical parts during the holiday period.
Mr O'Malley said a review of the plant's processing capacity, mechanical components, and pipelines was taking place.
Sludge and solids, which were still blocking some pipelines would be cleared to allow normal operations to resume, he said.
Spare parts were being ordered and stockpiled in an attempt to eliminate future supply issues.
A final cost to ratepayers was still to be determined, Mr O'Malley said.
