Designing urban systems tailored to climatic conditions

Climate change is expected to bring more intense and severe rainfall events, significantly increasing the risk of urban flooding. In his doctoral thesis at Luleå University of Technology, Iván Mantilla evaluates how soil-related factors—particularly the trade-off between soil moisture and soil permeability—influence the performance of two infiltration-based stormwater control facilities, a bioretention cell and a grass swale, in retaining runoff.

“Urban flooding is becoming more frequent and severe, and we need to rethink how we design and maintain our drainage systems,” says Mantilla, who recently defended his doctoral thesis in Urban Water Engineering at Luleå University of Technology.

Learning from modeling and experimentation

In his thesis, Hydrological Processes in Small Stormwater Infiltration Facilities, Mantilla combines modelling and field experiments to understand how infiltration systems behave under different conditions—from dry summers to snowmelt and heavy downpours. By studying how water moves through soil and vegetation, he identifies the factors that determine how much stormwater can be absorbed and delayed before it reaches the sewer system.

The research shows that design alone is not enough. Local conditions—such as soil type, vegetation, and seasonal moisture—strongly influence performance. By analyzing sites in different climates, Mantilla provides practical design implications to help urban planners create facilities that will perform under more variable future weather patterns.

“Understanding the physical processes behind infiltration helps us design systems that actually work—not just in theory, but during real rainfall events,” he explains.

Building resilient green infrastructure

His findings underline the importance of flexible, nature-based solutions in urban water management. Small, distributed systems can complement traditional drainage networks and reduce the burden on underground pipes.

“This kind of research brings science closer to practice,” says Mantilla. “If we integrate green infrastructure into our cities in a smart way, we not only prevent floods but also create more sustainable and liveable environments.”