Local Level Stormwater Harvesting and Reuse: A Practical Solution to the Water Security Challenges Faced by Urban Trees

Abstract

Water Sensitive Urban Design (WSUD) treatment devices are often used to restore natural drainage properties in developed catchments. WSUD can make positive contributions to the restoration of natural ecosystem processes, by supporting trees and habitats in urban areas without taking up limited urban space. This paper reports on the development and testing of a new WSUD device, the Wicking Tank. It is designed to supply sufficient volumes of water to urban trees through periods of drought via synthetic wicks from an underground storage tank to support adequate tree health. Relying on gravity fed stormwater, and the natural capillarity, adhesion, and cohesion properties of water and the process of hydraulic redistribution, water is transferred from the tank and into the rhizosphere of the tree. Water demand is controlled passively by the water potential differential across the root zone. Proof of concept testing of the Wicking Tank has shown the device to successfully draw water into soil to support the ongoing survival of a potted plant for over 20 weeks. Substantial differences are anticipated between this proof of concept test and an in-situ field trial. A field-based demonstration style version of the Wicking Tank is planned for construction and testing in 2015.

Reversible Thermally-Responsive Copolymer Valve for Manipulating Water Wicking

“…Wicking is a ubiquitous dynamic wetting process in which capillary force drives liquid flow in porous systems. , With the development of high technology, such as thermal management materials, − lab-on-a-chip , and electronic devices, , the complex and diverse application environment also puts more demands on the innovation of technology. Since wicking possesses miniaturization ability, simple equipment, and does not require external energy supply, it has been widely utilized in phase change boiling heat transfer, − water harvesting in arid environments, , moisture wicking wearable equipment, − micro biochemical testing platforms, and microfluid manipulation equipment. , In particular, wicking phenomena have become the hot direction of microfluidic manipulation technology development, such as precise one-dimensional fluid manipulation, two-dimensional planes for fluid collection, and dynamic liquid filling and mixing . However, few studies have focused on adjustable wicking with changes in the external environment, which is highly desired in advanced technology.…”