The term Low Impact Development (LID) refers to systems and practices that use or mimic natural processes that result in the infiltration, evapotranspiration or use of stormwater in order to minimise adverse impacts on water quality and associated aquatic habitat. However, LID practices can also have significant positive impacts on urban temperatures and contribute to reducing the Urban Heat Island Effect.
While floods are recognized as the most costly natural disasters in Canada in terms of insured property damage by water, extreme heat is a leading cause of death among climate change-related weather events. The severe implications for health were underscored by the impact of the heat wave in western Canada in the summer of 2021.
The good news is that heat-related illness and death are largely preventable with knowledge, education, and adaptive action. Recent national guidance produced by the Intact Centre on Climate Adaptation, with contributions from over 60 subject matter experts, presents a compendium of 25 practical actions that include green infrastructure solutions that work with nature. Guidance is provided for actions including planting and maintaining urban trees, extending vegetated area and water bodies, installation of green roofs and green facades/walls, which may also be considered LID practices.
It is evident that there are significant “win-win” opportunities that can be achieved by using LID approaches to simultaneously manage urban drainage and reduce extreme heat. This also highlights the need for “multi-risk” thinking in planning climate resilient development.
