More than 25,000 people have signed a new petition demanding the City of Montreal put a stop to its plans to temporarily dump raw sewage into the St. Lawrence River. 

The petition, named "The St. Lawrence is not a garbage," is addressed to Sorel-Tracy, Que., Mayor Serge Péloquin, as well as Montreal Mayor Denis Coderre and city hall opposition leader Luc Ferrandez.

It sprang up after the city announced this week it would have to temporarily divert a sewer interceptor, which would see eight billion litres of wastewater dumped into the river for a week starting Oct. 18.

The work is being done as part of the Bonaventure Expressway rebuilding project.

The announcement was swiftly met with public outcry, and was quickly — albeit temporarily — put on hold when Coderre demanded a second look.

It was restarted on Friday when the city said any other option would be too time-consuming and cost-prohibitive. 

Some experts have said the pressure of the river's current would push the sewage past the city in no time. 

Other experts have said putting sewage in the St. Lawrence would have a significant impact on the plant and animal life living in and along the water. 

Up until the 1980s, it was common to clear Montreal's sewers by emptying them out into the St. Lawrence, but it is no longer considered an acceptable practice. 

It's been six years since the city last dumped raw sewage into the river.