Why green roofs have the power to reduce flooding in cities Rachel Schoutsen Monday, April 26th 2021, 6:00 am - If more Canadians commit to green roofs, we could collectively reduce the harm caused by catastrophic flooding. Imagine a garden on your roof: plants growing, trees thriving, and, most importantly, excess water absorbed by nature rather than inundating your basement. The concept of a “green roof” has come to life in many cities across North America. Not only are they a stunning scene but also a solution to urban flooding. “A green roof is a system that you apply to a waterproof roof which allows you to safely and securely grow plants,” explained Steven Peck, Founder of Green Roofs for Healthy Cities.