Five million litres of raw sewage leaked into the Red River in Winnipeg over the course of nine days this month.
City officials were alerted to a strong sewage smell near St. John's Park on the morning of Jan. 19.
A city crew found lumber partially blocking a sewage line leading to a diversion station, which caused untreated waste to overflow into the river.
The lumber was removed and the sewage flow returned to normal by Tuesday afternoon.
Officials said the blockage may have been in place since Jan. 10.
The incident has been reported to Manitoba Conservation.
With a report from CTV Winnipeg
