Sustainable logging will safeguard against flood risks: UBC researchers

Dr. Younes Alila and his graduate student Henry Pham found that the “severely and consistently underestimated” impact of forest cover greatly affects B.C. flood risks.

University of British Columbia researchers have issued a call to recognize the power of healthy forests when coping with growing flood risks.

Dr. Younes Alila, a UBC faculty of forestry professor and hydrologist, and his graduate student Henry Pham, have synthesized decades of hydrology studies and found that the “severely and consistently underestimated” impact of forest cover greatly affects global flood risks.

According to Alila, when it comes to determining flood risks the risk is determined by typically looking at narrow and singular factors, instead of multiple interactive factors.

“… the risk of flooding is influenced by many things, such as how much snow is on the ground, whether it’s melting or not, how much rain is falling, and the characteristics of the landscape itself. These factors interact over time in complex ways,” UBC staff wrote in a press release. “Taking them all into account is called a ‘probabilistic’ approach and provides a better overall picture of flood risk.”

Pham said the probabilistic approach is used in other research, such as climate change and is the “most accurate method” for evaluating effects on environments.

Alila said B.C.’s flood risk is elevating due to losing forest cover, due to wildfires and large-scale logging.

“If we want to mitigate the costs of disasters like the 2021 flooding in the Fraser Valley or the 2018 flooding in Grand Forks, we need to change the way we manage our forest cover,” he said. “Regenerative practices such as selective logging, small-patch cutting, and other alternatives to clear-cutting are an important way forward.”