Mayor Gerald Tremblay fended off attacks on his credibility as he debated mayoral rival Louise Harel on French television Wednesday morning.

Harel, a former Parti Quebecois minister, had the upper hand at the start as she grilled Tremblay about the scandal-ridden water-meter contract that will be cancelled amid cost overruns and mismanagement.

She rejected Tremblay's assertions that he did not know the projected costs of the program had nearly doubled to upwards of $600 million.

She suggested the mayor had lost control of his administration, which has been rocked by a series of scandals in recent months.

Tremblay, who is fighting for re-election on Nov. 1, was able to turn around the debate, broadcast on the TVA network.

He reminded Harel about her divisive stint as municipal affairs minister under onetime premier Bernard Landry in the 1990s.

Harel masterminded the forced mergers of Quebec's largest cities that led to lawsuits and the eventual demerger of mainly-English-speaking towns on the island of Montreal.

Vague

Harel spent much of the debate on the attack but appeared unable to give specifics about her plans for economic development, public-transit improvements and a proposed centralization of the city's administration.

"Today Madame Harel has clearly indicated and proved that she has a superficial knowledge of the problems of the city of Montreal," Tremblay told reporters after the debate.

"I know the problems of the city of Montreal and I'm doing everything that is possible to solve the problems."

Harel, meanwhile, said Tremblay was evasive and that voters would take notice.

"Don't forget November 1st, it will be his administration that will be severely judged by the population," she said.

Project Montreal

Project Montreal Leader Richard Bergeron, who runs the city's green-focused third party, did not take part in the debate.

He'll join the other two leaders for a more formal televised debate next month.