A Thunder Bay lawyer leading a class-action lawsuit against the city says the expert report on what happened at the sewage treatment plant during May’s flooding leaves unanswered questions.

Sandy Zaitzeff said the consultant failed to address some key points.

Thunder Bay lawyer Alexander Zaitzeff says a consultant's report about the sewage plant during the May flood fails to address some key points. (CBC)

“They're talking about emergency bypass,” he said.

“Well there is a bypass for that plant, and they didn't talk about how it was used or not used ... and they talked about designing and adding a bypass. That should have been added a long time ago.”

Zaitzeff says the report was presented in a way to make the city look good, "so (city officials) could all pat themselves on the back.”

He said the engineering consultant pointed out some old debris had not been cleared from screens at the sewage treatment plant, but there was no mention in the report of why that maintenance had not been done.

“My take is that these reports were an attempt to … deflect liability,” Zaitzeff said. “Some people might call it a whitewash.”

While Zaitzeff still needs to read the reports presented to council Monday night and get some drawings from the city, the application for a class action seeking $300 million in compensation for damages related to sewer backups in homes is proceeding, he added.

Zaitzeff said a Thunder Bay judge has been appointed to manage the case.

He said he expects meetings will be held early in the New Year to set a schedule for how the case will develop.

A second application for a class action suit, filed by a Toronto law firm, seeks about $500 million in damages from the city of Thunder Bay.