Montreal didn't know it needed Ottawa's approval to dump sewage into St. Lawrence

The City of Montreal apparently didn't know it needed federal approval for its controversial proposal to dump billions of litres of sewage into the St.Lawrence River — until a month before it planned to do so.

A series of emails obtained by Radio-Canada from the federal government through an access to information request shows there was a misunderstanding over the project that dates back as early as September 2015.

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We are in a situation where a delay in the start date will put the whole project in peril.- Michel Malo, Montreal water treatment services 

An employee for the city wrote on Sept. 28 of that year he was surprised after the federal government, at that time headed by prime minister Stephen Harper, issued a reminder to Montreal that it was mandatory to have federal approval to move forward with the dump.

"I am surprised to receive your request today," wrote Michel Malo, who works for Montreal's water treatment services.

"We are in a situation where a delay in the start date will put the whole project in peril."

In the same email, Malo wrote the city was convinced that approval from the Quebec government was enough to proceed with the sewage dump due to a deal between Ottawa and Quebec.

The city believed a federal decree from March 2015 and Quebec's approval were enough to move forward — except the decree was never adopted.

Eventually, Montreal did receive permission, in November, by Canada's environment and climate change minister to proceed with the controversial dump but it had to meet of a slew of conditions first.

Over the course of four days in November, the city pumped 4.9 billion litres of sewage into the St.Lawrence River. 

The wastewater had to be diverted into the river to fix a 30-kilometre-long southeast interceptor, the city said.

'Extremely frustrating'

The emails reveal the frustration felt by some employees over the oversight just weeks before the sewage dump was slated to start in October.

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"How is it possible that the federal decree ... was never adopted?" wrote Tony Di Fruscia, a city engineer, to a federal counterpart.

He said "it's extremely frustrating" to deal with overlapping and contradictory information.

Montreal had informed Ottawa of its plans as early as 2014 but Environment Canada reached out a year later to remind the city it needed approval.

Emails also show Montreal tried to make the request for approval through an online system but said it didn't work.