Which practice is considered best for flood mitigation?

Encouraging stormwater infiltration is recognized as a best practice for flood mitigation because it allows rainwater to percolate into the ground rather than running off quickly into drainage systems or water bodies. This natural process helps to reduce surface runoff, which can overwhelm urban drainage systems and lead to flooding. By promoting the infiltration of stormwater through techniques like permeable pavements, green roofs, and bioretention areas, sites can manage rainwater more effectively. Infiltration enhances groundwater recharge, improves water quality by filtering pollutants, and can help manage the volume and timing of stormwater discharge, thereby reducing the likelihood of flooding.

In contrast, increasing impervious surfaces tends to exacerbate flood conditions by preventing water from soaking into the ground, resulting in increased runoff. While hard engineering solutions, such as levees or concrete channels, can temporarily manage water levels, they often do not address the root causes of flooding and can lead to habitat loss and other environmental issues. Relying only on concrete drainage methods may provide quick fixes but neglects the importance of sustainable practices that work in harmony with nature to manage stormwater effectively.