"No one knew that the sludge had built up and that it was going to tip over."
She could not give a cost to remove the sludge.
She told the protesters that in the meantime the council was suppressing the smell with lime, which caused howls of discontent from some that the smell still wafted over their suburbs.
Ms Main apologised and empathised with the protesters.
"Our quality of life is being affected and people have the right to say money should be spent wisely."
She said there was $2 million in the budget over the next two years to work toward a solution.
Another disgruntled protester said the stink had caused her to vomit.
Ms Main quoted the Medical Officer of Health, who says that anyone who thinks they are suffering should go to their doctor.
That was small comfort to the woman who said she would have to pay and the remedy would not eliminate the cause.
Ms Main said they all felt let down, as did she.
She said those who designed the plant in 2005 thought it was the right decision at the time.
It was built in 2006 and opened in 2007. Only four years ago, Wanganui's wastewater was still going into the Tasman Sea.
Ms Main said all of this was before she took office, but she was not going on a witch hunt and looking to blame anyone.
"It was always going to fail ... it should have been built bigger, but sometimes the evidence is not so clear."
Ms Main said whatever was done next had to be right
Another protester asked why the council did not dump the wastewater into the sea.
Ms Main replied that the council was looking to see whether it could do this.
"It is a very very complex problem,"she said.
Monette Robinson was interested to come and listen to what was being said, and suggested that, for everyone to be part of the solution, Portacoms should be placed in all the suburbs.
"We are all complaining, but we are all putting the sewage there."
Another solution, she said, was to copy the Swedish biological system of biobeds and worms to sanitise the sludge.
On February 19, the Wanganui District Council's infrastructure and property committee heard first-hand from consultants Cardno BTO about the condition of the ponds and efforts to stop the stench.
Mike McCoy, business unit manager for the Wellington firm, said while short-term measures were having an effect on the odour, it would only be fixed with a long-term solution.
Mr McCoy said his team was investigating long-term options and a report to the council should be ready within two months.
Adding lime slurry and pre-treating waste at Beach Rd before it got to the ponds were short-term solutions, while using aerators to oxygenate the ponds was a medium-term option.
