Use of Hydromedia Low Compactability Pervious Concrete Sidewalks for Efficient Stormwater Control to Regulate Rainwater Access to Tree Roots - A Toronto Case Study

摘要

As the nature of urban growth relies on the increasing development of impervious surfaces, the need for more effective on-site management of the water cycle is apparent. Without sufficient access to rainwater and soil space, trees and their roots are unable to properly sustain themselves in the urban jungle. Providing a cost-effective, and efficient, on-site solution toward allowing direct access for stormwater to tree roots, while maintaining proper soil conditions for natural root growth, is thus necessary. This paper focuses on the successful implementation of the Hydromedia Low-Compactability Pervious Concrete (LCPC) system, as a replacement for conventional impervious concrete sidewalk boulevards, in order to address this demand. Long-term performance monitoring of the system is ongoing for Toronto-based testing strips. By replacing the impervious space, the LCPC system becomes an effective and efficient solution exceeding the typical minimum design standards. Due to its high porosity content of up to 35% (relative to the minimum 15% specification for pervious concrete), LCPC is able to provide drainage up to 1000 L/min/m~2 in order to effectively infiltrate most rain events directly into the soil below, far surpassing the minimum criterion set out by most municipalities. The system aims at effectively replenishing the water table, and providing sufficient rainwater drainage and quality, to sustain a tree root system, all while effectively meeting the functional requirements of the average sidewalk or other pedestrian surfaces.