In the heart of Budapest, where the Danube River’s mighty flow meets the city’s urban landscape, a fascinating interplay between groundwater and surface water is unfolding. This dynamic relationship, crucial for municipal areas, is being scrutinized by researchers, particularly in light of recent floods. The study, led by Wagner Flóra from the Department of Hydraulic and Water Resources Engineering at the Budapest University of Technology and Economics, sheds light on how construction activities might be altering these natural processes, with significant implications for the energy sector.
The Lágymányos area in Budapest serves as a living laboratory for this research. Here, the groundwater level is deeply influenced by the Danube, a relationship that becomes particularly evident during floods. “The interaction between groundwater and surface water is a complex dance,” explains Flóra. “Buildings with underground structures can obstruct this dance, and we’re seeing how this obstruction changes over time.”
The study focuses on two riverside buildings constructed between the floods of 2010-2013 and the recent floods of 2023-2024. By frequently monitoring groundwater levels and comparing them to the Danube’s water level, Flóra and her team have computed the specific groundwater discharge. The results are visualized through loop rating curves, which are then approached with ellipses for estimation. “When buildings obstruct the groundwater flow, the parameters of these ellipses change,” Flóra notes. “This change is a clear indicator of how construction activities can alter the natural flow regime.”
The implications of this research extend beyond Budapest. In municipal areas worldwide, understanding the interaction between groundwater and surface water is crucial for sustainable urban planning and infrastructure development. For the energy sector, this knowledge is particularly relevant. Groundwater flow regimes can significantly impact geothermal energy projects, which rely on stable groundwater levels for efficient heat exchange. Moreover, changes in groundwater flow can affect the stability and longevity of underground energy infrastructure.
The study also highlights the importance of long-term monitoring. By comparing data from wells with and without nearby underground structures, Flóra and her team have shown that construction activities can have a measurable impact on groundwater flow. “Further investigations could lead to an easier quantifying of the specific groundwater discharge,” Flóra suggests, pointing towards future research directions.
Published in the Slovak Journal of Civil Engineering, known in English as the “Slovak Journal of Civil Engineering,” this research provides a valuable contribution to the field. As cities continue to grow and develop, understanding and managing the interaction between groundwater and surface water will be key to ensuring sustainable and resilient urban environments. For the energy sector, this research underscores the need for careful planning and consideration of groundwater flow regimes in the development of underground infrastructure. As Flóra’s work shows, the dance between groundwater and surface water is a delicate one, and one that we ignore at our peril.