The City of Montreal has decided to go ahead with a controversial plan to flush 8 billion liters of raw residential and industrial sewage into the St. Lawrence River.
The mayor had suspended the decision and ordered a review earlier this week amid backlash from local politicians and residents. But at a press conference on Friday, officials announced that the original plan is a go.
Starting Oct. 18, and for roughly seven days, the equivalent of 2,600 Olympic-sized pools of sewage from Montreal boroughs of LaSalle, Verdun, and Notre-Dame-de-Grace will gush into the St. Lawrence River, which is the gateway from the Atlantic Ocean to the Great Lakes. The city says it has to do it because it has to close a major sewer interceptor while constructing the Bonaventure Expressway.
"All possible alternatives to the spill have been considered and it is the only option, " Pierre Desrochers, president of the city's executive committee, said in a statement. He called the work "essential maintenance" and said that improving the interceptor will result in fewer overflow episodes on the south side of the island of Montreal.
The city says the sewage represents less than 1 percent of the average volume handled by the main water treatment plant in the area.
Real Ménard, who is the head of sustainable development, the environment, large parks and green spaces at the city, said the municipality has taken all possible precautions to limit the impact of the spill, including picking a time of year outside of aquatic breeding season in the river.
The volume of waste water is lower and the temperature of the water is 13 degrees on average, which limits the growth of bacteria, noted Ménard.
"Following a detailed analysis of the situation, we now have the belief that our decision is right. Montrealers understand that this decision would not have been authorized without us having the certainty that all measures have been taken to limit the negative impacts of a spill," Desrochers added.
In an earlier interview, a civil engineer told VICE News that although not ideal, there is likely no other option for Montreal given the circumstances.
The only long-term problem Ronald Gehr, a professor at McGill University whose research includes wastewater treatment processes, foresaw is the accumulation of sediments.
As for the drinking water, Gehr says towns that are downstream "might have to be more careful with their disinfection. They might see a slight increase in E. coli, but it would be quite small."
Tamara Khandaker contributed to this report.
Photo via Flickr Creative Commons user Doug Kerr