Measuring how much Water our Street Trees Use

Have you noticed some of our street trees wrapped in hessian behind tall guards? 

Council, with grant funding from the Adelaide and Mt Lofty Ranges Natural Resources Management Board, is collaborating with Flinders University to see how our street trees might assist how we engineer our stormwater drainage and flood mitigation work. 

Because water evaporates from their leaves, trees work like big, organic, evaporative air conditioners to keep our suburbs cooler. By drawing their water from the ground and by redistributing soil water around their root systems, Council’s trees might also increase the capacity of our stormwater soakage systems. 

Flinders University student Ms Xanthia Gleeson, under supervision of hydrologist Associate Professor Huade Guan, is investigating how much water our street trees use. 

An electrical resistivity tomograph was used to identify active sapwood in the tree’s trunks so sap flow meters could be attached. The sap flow meters will show how much water trees use where stormwater is soaked into the soil compared to others growing in sites where stormwater is drained away. 

This study will give insights into how much our trees benefit from the extra water but also whether the trees increase the amount of stormwater that we can harvest. 

This research might one day lead to trees being valued not only for their environmental and aesthetic benefits but also for their effective contributions to sustainable stormwater management.

Measuring how much water our street trees use April 2019 ERT on treeMeasuring how much water our street trees use April 2019