Twenty-first International Conference on Environmental, Cultural, Economic & Social Sustainability

Abstract

A rapidly increasing population, together with climatic variability and climate change are contributing to severe water scarcity in Australia. One promising development in stormwater management is the kerb-side inlet system, which is designed to harvest stormwater runoff from residential streets and arterial roads for the irrigation of street trees and first flush. These systems efficiently capture the initial surge of stormwater, thereby mitigating and bioremediating pollutants and nutrients that could otherwise impact receiving waters through toxicity or algal blooms. This research examines the performance of kerb-side stormwater harvesting devices situated within the root zones of street trees. Field observations have measured high infiltration rates, with some locations registering up to 5 kilolitres of harvested stormwater annually. This was achieved with low maintenance requirements – essentially routine street sweeping. Importantly, this implementation had no discernible impact on seasonal ground movement. A regular survey of kerb elevations along research site, measuring ground movement linked to enhancing soil moisture. We collected data between 2014 and 2016 regarding ground movement in response to stormwater harvesting through kerb-side inlets at the case study site. A total of 160 survey points were strategically placed at the inlet locations, midway between them, and in the asphalt road surface 2m from the kerb. The current research project has demonstrated that stormwater harvesting and infiltration through kerb-side inlets has multiple beneficial effects. This includes increased growth of diameter of saplings by 77%, enhanced transpiration in both saplings and mature street trees by 17% and 21% respectively.