Work at the Longueuil treatment center could lead to the discharge of 300 million liters of untreated wastewater into the St. Lawrence River in 2022.
Posted at 10:25 a.m.
The city will have to deprive itself of a third of its sanitation capacity for three periods of work: one in the winter and two in the fall.
During each of these periods, the treatment center could lose up to 100 million liters of wastewater, Longueuil estimates. These spills, which will go directly into the river, should only occur in the event of rain or snowmelt.
Longueuil obtained a certificate of authorization from the Ministry of the Environment to proceed with this work despite the risk of spillage. Municipalities and institutions downstream from Île Charron, where the wastewater treatment center is located, have been notified.
Longueuil is already considered a bad student when it comes to wastewater treatment. In 2020, it carried out 1013 spills in the St. Lawrence River.
The maximum spill predicted by Longueuil is much lower than the spill carried out by the City of Montreal in 2015, which caught the attention of the public. At the time, 8 billion liters of untreated sewage had been dumped.