A new water treatment plant and accompanying infrastructure for Saint John has been estimated at $220 million. (CBC)

Saint John's former commissioner of municipal operations says he is not in favour of hiring private partners to build and operate a new water treatment plant for the city.

Paul Groody contends the privatization of water is a "fundamentally flawed premise" and spoke publicly on the issue at a forum Wednesday night at the Saint John Arts Centre.

"A P3 does not provide cheap financing, nor does it resolve water governance responsibilities," he said in a statement.

"Such a course of action for drinking water would be a costly, wasteful, avoidable mistake," said Groody, who was in charge of the municipal water and sewage system for 13 years before retiring in 2011.

In March, council voted 7-1 in favour of going the P3 route, beginning with an application to the federal government for funding.

A consulting firm has said the city could save millions of dollars by enlisting a private partner to build and operate a new water treatment plant.

"The P3 would be less expensive than the traditional procurement model by approximately $3.2-million," Johanne Mullen, a representative of PricewaterhouseCoopers has said.

P3 rejected by previous councils

Under the P3 model, Saint John administrators would get the comfort of knowing exactly what the price would be and how long construction would take, according to the consultant's report.

It also suggests the new system could be operating sooner, and the city would be more likely to get funding from the federal and provincial governments.

The water plant itself and some accompanying infrastructure was projected to cost $220-million. Information on exactly how much council expects the upgrades to cost was redacted.

Coun. Bill Farren, who represents Ward 1, was the only member of council to vote against moving to a P3 model.

"I'm just not 100 per cent convinced that it's going to be cheaper for the residents of Saint John at the end of 30 years," he had said.

Previous councils have discussed but rejected the idea of a public-private partnership.