The sewage came from the town's beleaguered Project Pure wastewater system near the Cardrona River.
Residents yesterday demanded answers about potential waterway contamination, while the Queenstown Lakes District Council insisted there was no risk posed, despite some "seeping" at the site for up to a year.
Several people contacted the Otago Daily Times yesterday worried about the steady flow of raw effluent coming from a pipeline alongside State Highway 6, between Morris and Riverbank Rds. It was pooling in a large temporary reservoir in a paddock below, about 50m east of the Cardrona River.
The spill was initially seen gushing several metres into the air yesterday morning before United Water workers reduced the pipeline pressure.
QLDC Three Waters manager Gerry Essenberg said a faulty air valve had caused "seeping" from the pipeline for about a year, which had steadily worsened.
A routine repair had been scheduled for this week. But the leak had become bigger and trucks were brought in to pump the effluent out, he said.
"It's taken such a long time [to fix] because it was not a simple job to do; it needed a lot of planning," Mr Essenberg said.
About 160cu m of effluent inside the pipe had to be removed. Pumping continued at the site yesterday and Wanaka's wastewater was diverted to Albert Town's emergency overflow pond. Mr Essenberg expected the repair job to be completed today.
He said the spill was "contained" and there was no risk of it reaching the Cardrona River.
However, Black Peak Rd resident Nick Busse, who had observed the "rather large flow of raw effluent" since Sunday evening, believed the council was "downplaying" the situation.
"I'm a bit surprised [no contamination will occur] given the alluvial quality of the ground there," Mr Busse said.
A spokesman from the Halliday Rd water group - about 12 residents who draw water from a bore about 300m away from the pool of effluent - was also concerned about contamination.
The spill made a "mockery" of Project Pure, the spokesman, who asked not to be named, said.
He supported Mr Busse's call for council accountability.
Otago Regional Council environmental services manager Martin King said it did not look as if discharge had gone into the river, but an investigation into the spill would be carried out.
