What you need to know about this project  

When? 

April 2025 to fall 2026 

Where?  

Rue Lighthall, between Boulevard Saint-Laurent and Rue Clark 

What?  

Most of Montréal’s underground wastewater network is a combined network. This means that household wastewater and rainwater flow through the same pipes to the wastewater treatment plant. Entrance buildings are positioned at strategic points in the wastewater collection network. They provide access to underground motorized valves that are remotely controlled by a computer system. These buildings play a key role in controlling wastewater levels in the pipes and preventing overflows. All this equipment needs to be checked and maintained. As part of the project, the valve control equipment that is currently located under Rue Lighthall will be moved aboveground. The equipment also needs to be replaced. It is about 30 years old and has not yet been upgraded. What’s more, the current structure can lead to health and safety issues for workers. Also, moisture in the underground chamber may be harmful to the equipment. 

Why?  

The wastewater control valve is broken and needs to be opened manually. This valve must be repaired to better control water flow and avoid overflows. In addition, to improve worker safety, a new entrance building will be built at this location. For now, the chamber and equipment are underground.