Stormwater management is no longer optional

Urban growth, climate change, and combined sewer systems have led Montréal to strengthen its regulations. Since 2020, rainwater collected on any property with an impermeable surface of more than 1,000 m² must now be managed or retained on-site to reduce sewer system overload and help limit overflows into the Saint Lawrence River at the J-R Marcotte treatment plant.

For civil engineers, excavation contractors, and builders, this requirement adds complexity and uncertainty.