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

The City of Montreal apparently didn't knowit needed federal approval for its controversial proposalto dumpbillions of litres of sewage into the St.LawrenceRiver until a month before it planned to do so.

A series of emails obtained by Radio-Canada from the federal governmentthrough 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.- MichelMalo, Montrealwater treatment services

An employee for the citywrote on Sept. 28 of that yearhe was surprised after the federal government, at that time headed by prime minister Stephen Harper,issued a reminder to Montrealthat 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'swater treatment services.

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

In the sameemail,Malo wrotethe city was convinced that approval from the Quebec government was enough to proceed with the sewage dump due to a dealbetween Ottawa and Quebec.

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

Eventually,Montrealdid receivepermission, in November,byCanada'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 bediverted into the river to fix a30-kilometre-longsoutheast interceptor, the city said.

'Extremely frustrating'

The emails reveal the frustrationfelt by some employees over the oversightjust 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'sextremely 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.