An assistant professor from the University of Prince Edward Island (UPEI) has proposed a new way to project the risk of urban flooding caused by heavy precipitation.
Xander Wang of the UPEI school of climate change and adaption released his findings in a paper titled Urban Flood Prediction Under Heavy Precipitation, which was published in the Journal of Hydrology.
"We are seeing more frequent flood events, especially in cities around the world," Wang said. "In the context of global warming, we are seeing more water coming from the ocean, to the air, and to land surface. Under global warming, this has intensified significantly.”
Wang told CBC News that it is typically challenging to create flooding models for urban settings. Unlike natural watershed models, urban areas are made by human hands and modified by human activity, which means more variables affect the way flooding behaves in cities and the like.
"It's very complicated systems so we need to use a new model to deal with that," the professor remarked.
According to Wang, his mathematics-based model provides a real-time prediction of flooding. This allows urban communities to closely follow flood developments as they occur in real-time, and immediately respond to the situation. The model can also be used to predict potential flooding in advance.
Wang’s model proposes dividing an irregular urban area into grid cells. The model reflects the frequent inflow and/or outflow interactions among grid cells while capturing the rapid generation of surface runoff in urban areas during heavy rainfall. The model also accounts for urban area features, such as large-scale impermeable surfaces and urban drainage systems, to better simulate the floods.
The researcher tested his model by reproducing the 2016 flood in Lafayette Parish in Louisiana; Wang noted that the model performed well in simulating the scenario.
"We can set up different global warming scenarios and then [look] for patterns and then you can see where it's going to be flooded for the future," the assistant professor mentioned.
Wang has suggested that his model can be used to predict PEI’s future flooding, which can help plan for infrastructure development.