Climate Resilience and Flood Risk Assessment
As part of its 2025 Sustainable Development Plan, a major public infrastructure owner in Montreal engaged Lasalle | NHC to assess the vulnerability of its assets to heavy, short-duration rainfall that could overwhelm underground drainage systems, leading to surface water accumulation and increased flood risk.
Confidential
Climate & Watersheds
Montréal, Québec
Using high-resolution topographic data, Lasalle | NHC developed 14 hydraulic models in HEC-RAS 2D to simulate flood behaviour across the study areas. The models replicated surface water flow during extreme rainfall capturing how runoff moves across the landscape based on existing site topography. The results were validated against documented flooding events to ensure a reliable representation of real-world conditions. Extreme water levels resulting from 25-year and 100-year storm events were then assessed against critical infrastructure thresholds to identify vulnerabilities and support informed climate adaptation planning.
Provided a deep understanding of flood risk under current climate conditions using modelling, enabling proactive infrastructure planning, targeted resilience investments, and improved protection of critical public assets.
