Thinking in Systems

How Philippe Van Cappellen’s research through Global Water Futures is changing the way we analyze and manage water quality of freshwater ecosystems.

Water is essential for everything we do as humans – whether it is to produce our food, in industrial processes, or in our homes, says Philippe Van Cappellen. “In turn, everything we do has an impact on water.”

Van Cappellen is the Canada Excellence Research Chair Laureate in Ecohydrology at the University of Waterloo, where his research focuses on the processes and drivers that control water quality, from nutrient enrichment and urbanization to micropollutants and climate change, to name a few topics.

“What motivates my research is how we find ways to address the broad range of risks that threaten water quality. Increasing temperature in a lake, for instance, can escalate harmful algal blooms, while flooding events mobilize contaminants that then make their way into our waterways and, potentially, in our drinking water sources.  A research priority in my group is to assess the vulnerability of our water resources and freshwater ecosystems to these and other mounting pressures to formulate preventive policies and practices.”

Water quality is not always something you can see, Van Cappellen adds, but if we want a sustainable future, we need to protect it. “This is the only way we can keep our waters swimmable, drinkable, and fishable.”

Following the research

Van Cappellen is also active through Global Water Futures (GWF), where he participates as a member of the Strategic Management Committee and as the Faculty Lead for the Water Quality Modelling Core Team. He is also funded through GWF to look at the impact of urbanization on water quality. This led one of his PhD students, Jovana Radosavljvic, to uncover an unexpected impact of road salt on lake water quality.

“We were analyzing historical water quality trends in Lake Wilcox, a kettle lake in Richmond Hill, Ontario, to understand how these trends connect to land use changes and climate impacts,” Van Cappellen explains.

The team observed how the lake’s water quality started changing as farming in the lake’s watershed expanded, and following World Water II, rapidly deteriorated with agricultural intensification. When the region starting to urbanize in the 1980s, agricultural activity decreased, along with the nutrient-rich runoff from farmland. However, algal blooms – which are typically attributed to high nutrient runoff entering a lake – were still observed in the lake.

As the built environment grew and the land use changed, the application of road salts during winter increased. “Since the 1980s, the nutrient loads were slowly declining while the data did not show a significant change in the region’s climate. It turns out that the observed water quality trends were connected to the increased use of road salt that, in turn, was elevating the salinity in the lake,” Van Cappellen says.

Water quality is everyone’s challenge

Water quality impacts of salinization are a global problem, he says. “As humans, we generate a lot of salt contamination. As a result, we are salinizing lakes around the world.”

Being part of Global Water Futures has allowed Van Cappellen and his team to expand their research to include a variety of drivers of water quality changes and offer useful data and tools to the agencies that manage our freshwater resources.

“For decades we’ve thought about eutrophication as mostly a problem connected to phosphorus inputs from agriculture,” he says. “But our research shows that it’s not only about lowering the phosphorus input. Managing water quality requires a holistic approach that considers all the actors and potential trade-offs; we can’t put the burden on farmers alone.”

Working together for healthy lakes

By collaborating with partners, Van Cappellen and his team are putting their findings into action. For instance, they have developed simple metrics for the Canadian and U.S. agencies that manage the Great Lakes so they can evaluate the likelihood that proposed measures to mitigate algal blooms will deliver the expected results. One aspect this work underlines is the importance of thinking of the Great Lakes as a hydrologically interconnected system.

“This is a change in the way that we’ve traditionally managed the Great Lakes,” he says. “As a researcher, I don’t make the policies, but I’m glad to see our science informing these conversations, supporting better decisions, and opening doors for more sustainable water quality management to protect our ecosystems and shared resources.”

The bigger picture

Joining Global Water Futures has had a huge impact for Van Cappellen, he says.

“Being part of the Global Water Futures initiative has broadened my network – I’ve made valuable connections with researchers in other disciplines and across geographies. Working with this community and connecting the dots between our research has challenged me to think differently about my own research and how our team can have a material impact on water security.”

Global Water Futures has also offered new opportunities to Van Cappellen’s students. “They, too, have benefitted from thinking about the bigger picture when it comes to how the world manages water. We need to look at all pieces of the puzzle.”

On a personal level, he adds, the experience has even changed the way he teaches his undergraduate courses. “I talk much more about water quality as part of the greater water cycle,” he says. “This will influence the way we think and how we organize future water research. We can achieve a lot when we work together.”

Importantly, the program has also played a role in putting Canada on the global stage. “We are part of a country where water research is valued,” Van Cappellen says. “That’s exciting!”