Montreal Mayor Denis Coderre went 35 metres underground on Thursday, to inspect sewer repair work on day two of the city's raw sewage dump.

Sewers in the Montreal area began diverting wastewater into the St. Lawrence River on Wednesday, so city crews can complete work on the aging infrastructure and relocate a snow chute.

Coderre said the dump, which will see eight billion litres of untreated wastewater discharged into the waterway, will last one week. 

Hours after the sewage dump began on Wednesday, city workers were on the water with nets, plucking larger debris from the surface.

Nearby residents were quick to complain of an odour coming from the water, but Coderre said that's normal.

“Of course, when you first open it, you have some odour," he told reporters in Montreal on Wednesday. "But it dissipated pretty fast."

Sewage dump sparks protests

For the second consecutive night a group of protesters blocked access to a Montreal bridge to show their opposition to the sewage dump.

Organizers were hoping 200 people would attend the demonstration Wednesday night, in order to completely shut down the Mercier Bridge, but only approximately two dozen protesters showed up.

With files from CTV Montreal