Repurposing rainwater runoff 

There are few sights more frustrating than seeing gallons of rainwater run down your roof and into storm drains after a deluge. To combat this, scientists from Flinders University are working on an innovative project transferring this water to at-risk urban trees in Adelaide, South Australia. 

Too much rainwater wasted

The Drywells and Trees Project (a collaboration with the University and Hort Innovation, a not-for profit horticultural research organisation) is attempting to use the untapped potential of rainwater runoff to revitalise backyard trees struggling with drought conditions.

According to Hort Innovation, private residences in Adelaide recycle under 4 per cent of the rainwater collected on their roof catchments. Furthermore, many residences in Adelaide lack sufficient space for rainwater tanks to store runoff, which compounds this waste.

New solutions 

“One possible solution is to integrate urban tree and stormwater management together,” says Professor Huade Guan, lead researcher for this project. “For known vulnerable trees and locations, stormwater harvesting devices can be installed to provide more water for the trees.” 

One such device that the project is developing is a Water Sensitive Urban Design (WSUD) apparatus. The WSUD connects roof catchments with a dry well (a gravel pit that stores rainwater and slowly disperses it into the soil) that links directly to the soil beneath trees in need of water.  

Tree research 

A recent study from Guan and his colleagues sets out a way to define the ability of different tree species to resist the effects of drought. “Knowledge of which trees … do not cope with droughts in Adelaide would be useful for informed urban forest management to keep our city greener and cooler,” Guan says. Understanding the unique properties of each tree equips local councils to combat the effects of drought.

For more information on this project visit: Hort Innovation.

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