Harnessing Recycled Water for a Greener Future
Sydney’s western suburbs face extreme heat, with temperatures reaching 48.9°C in 2020. Recycled water can safely irrigate parks and sports fields, reduce water use, and create cooler, more liveable spaces—helping fight extreme heat in Western Sydney.
Working with Macquarie University and Sydney Water, Botanic Gardens of Sydney is part of exciting research that explores using recycled water to enhance urban green spaces. The results will help shape greener, cooler, and more sustainable cities while reducing the reliance on drinking water for non-potable uses.
The Study Site: At the Australian Botanic Garden Mount Annan, you can visit the study site of 600 trees. Half these trees are watered with recycled water and half with potable water, to investigate resulting differences in growth and cooling benefits.
The Project: The project uses new smart technology and monitoring systems on site to measure soil moisture, salinity, micro-climate and plant growth.
15 native tree species were selected to be part of the study. This will provide vital data for urban planning, focusing on which trees thrive when irrigated with recycled water. Planners will be able to optimise green spaces for climate resilience and cooling.
Discover more
Follow the Flow water trail through the Botanic Garden to find out more! Across the garden, 11 locations, including the study site, have been chosen to highlight the importance of water in our landscapes, cities and communities.
Project Partners
The tree plots are monitored weekly. Researchers measure growth rates, chlorophyl levels and soil moisture. 
This infrared image shows how tree cover can dramatically affect air temperature.