More efficient green urban infrastructure
At a time when climate disruptions are having a noticeable impact on water management, particularly during periods of heavy rainfall, a growing number of towns and cities are installing vegetated systems such as bioretention areas, which form part of a group of solutions known as ‘green infrastructure’. Because of their many benefits, ranging from greening and controlling run-off to filtering contaminants from stormwater, reducing urban heat islands and protecting biodiversity, green infrastructure solutions are emerging as one of the tools that will enable municipalities to better respond to climate challenges over the coming decades.
As these methods have only been introduced relatively recently in Québec, it is important to document their performance, says Professor Françoise Bichai from the Department of Civil, Geological and Mining Engineering at Polytechnique Montréal. Accompanied by graduate students, she has therefore initiated several interdisciplinary collaborations to analyse the contexts in which these systems are most effective.
In collaboration with the City of Trois-Rivières, the researcher and her team were able to collect data for a major project on Rue Saint-Maurice, which incorporates 54 bioretention cells over a 1.3 kilometre stretch of road. For example, students carried out fieldwork to document the performance of certain cells in reducing local runoff and some of the contaminants carried by stormwater. Another student carried out hydraulic and hydrological modelling, factoring in the impact of snow accumulation and melting. These data, rarely included in the scientific literature, are important to consider when assessing runoff and the performance of bioretention systems, as this work has shown.
These highly promising research projects have given Françoise Bichai the opportunity to broaden the scope of her collaboration not only with the municipality of Trois-Rivières, but also with experts from around the world and from a wide range of disciplines, including engineering, social sciences, planning and urban development. Because an interdisciplinary approach is essential if we are to reap the many benefits of green infrastructure and plan its implementation more effectively.
References
Le Cauchois, P., Doucet, S., Bouattour, O., McQuaid, N., Beral, H., Kõiv-Vainik, M., Bichai. F., McCarthy, D., St-Laurent, J., Dagenais, D., Bennekrela, N., Guerra, J., Hachad, M., Kammoun, R. et Dorner, S. (2025) Full-scale characterization of the effects of a bioretention system on water quality and quantity following replacement of a mixed stormwater and combined sewer system. Blue-Green Systems, 7 (1): 43–62: https://doi.org/10.2166/bgs.2025.029
Gougeon, G., Bouattour, O., Formankova, E., St-Laurent, J., Doucet, S., Dorner, S., Lacroix, S., Kuller, M., Dagenais, D. et Bichai, F. (2023) Impact of bioretention cells in cities with a cold climate: modeling snow management based on a case study. Blue-Green Systems, 5(1), p. 1-7. https://doi.org/10.2166/bgs.2023.032
Lacroix, S., Kuller, M., Gougeon, G., Petrucci, J., Lemieux-Chalifour, F., Rioux, A., Dagenais, D. et Bichai, F. (2024) Can we stop reinventing the wheel in blue-green infrastructure planning? Using value-focused thinking to enable transferability of a multicriteria planning support system. Wiley, Landscape and Urban Planning, vol. 252, p. 105188. https://doi.org/10.1016/j.landurbplan.2024.105188