Raymond Desgagnés said garbage has been washing up on the shore of his property since he bought it in 1996. He said he's concerned about the safety of his grandchildren.
"It's terrible for the skin. I don't want my granddaughters to walk along the banks barefoot, that's for sure," he said. "Anything that you flush down a toilet ends up here."
The city of Montreal said the problem is caused by cross-connected pipes.
Concordia University engineering professor Adel Hanna said cross-connected pipes can cause sewage to be pumped into the river, along with rain water, during a storm.
Pointe-aux-Trembles councillor Caroline Bourgeois said the pipes are the city's responsibility.
"We are waiting for the report from the City of Montreal administration. It will give us indication about how to resolve this problem," she said.
In a statement, the city said it has completed an investigation into the situation and will release a report to the borough in the coming weeks