Water wise

Nature-lover Sally Thompson has devoted an esteemed engineering career to the changing role of water in human and natural systems.

The passion that continues to shape Associate Professor Sally Thompson’s career in environmental engineering was seeded at a tender age. Enchanted by Gerald Durrell’s much-loved children’s book The Fantastic Flying Journey, as a seven-year-old she became both a lover of the natural world and someone with a prescient sense of the forces that threaten it.

“Even as a little tacker, I was worried about environmental problems,” Associate Professor Thompson recalls, “because you could see them, you know. If you went for a drive in the Wheatbelt in the 80s, you couldn’t escape the salt lakes. You could see the salinisation. I became more and more aware that much of what I could see — the environmental threats that were beginning to mount — were a product of misplaced land management and that many of the potential solutions were about engineering in the landscape.”

Armed with an undergraduate degree from UWA, Associate Professor Thompson soon found herself swept away from her beloved home state, completing a PhD at Duke University in the US and then working as a postdoctoral scholar at Princeton and Purdue universities. From there she was appointed Assistant Professor of Surface Hydrology at the University of California Berkeley, ultimately promoted to Associate Professor with tenure in 2017. While her years abroad delivered many unique research experiences — from studying wave modelling in Lombok to hunting for missing rivers in India — Associate Professor Thompson jumped at the opportunity to return to UWA in 2019.

“One of the really positive things for me about coming back to WA is that from a research perspective, we do have these very close ties with industry and with government who are a joy to work with,” Associate Professor Thompson says. “They tend to be focused, forward-looking people who genuinely listen.”

One of the projects her research team is currently working on with the WA Department of Water and Environmental Regulation involves monitoring groundwater recharge — the replenishment of the water table from rainfall. “Here in the city we get about 40 per cent of our drinking water from our groundwater. Groundwater also supplies most irrigation water for market gardens and Perth backyards. It keeps our wetlands wet and is also used by industry.

“While there has been a lot of monitoring of groundwater levels, we haven’t done much monitoring of what recharge is doing: how it’s changing between wet years and dry years or between places with deeper or shallower groundwater levels. The big question is what will recharge do in a changing climate, because we are going to be increasingly dependent upon groundwater as the climate dries.”

In the agricultural research space, Associate Professor Thompson’s research team has been working at UWA Farm Ridgefield to install a ‘Critical Zone Observatory’. It’s a blue-sky project that aims to track and measure the complete vertical journey of water from sky through the soil — pulling together all the processes and elements that are traditionally studied in isolation by different areas of expertise. It’s a national project led by Associate Professor Thompson, with four other sites being developed in South Australia, New South Wales and Queensland.

Her team is also working with Associate Professor Nik Callow, from UWA’s School of Agriculture and the Environment, on a project called ‘Smart Dams’. A response to the fact that dams are becoming increasingly less effective in insulating WA farmers from water shortages, Smart Dams is exploring technological and geological solutions to evaporation suppression and to enhancing the amount of run-off that can enter dams.

Associate Professor Thompson says: “Smart Dams is working with four regional grower groups in a genuine partnership — university researchers working closely with people on the ground.”

Read the full issue of the Winter 2023 edition of Uniview [PDF 2.7Mb]. The Uniview accessible [PDF 2.9Mb] version is also available.