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The Kurikka area in western Finland is an example of the complex groundwater system with an important connection to the fractured bedrock. The leaky confined aquifer system developed in the glacial sediments overlying the bedrock. Location, dimension, and connectivity of bedrock deformation zones constitute a big uncertainty in the 3D geological model. To image sediments and bedrock structures, we acquired 2D multicomponent seismic data using a nodal system and planted 3-C geophones as receivers and an electrically driven seismic vibrator (E-vib) operating in both the P- and S-wave mode as a source. Acquired 6-C data confirm the benefits and complementary nature of the P- and S-wave imaging in such conditions. Seismic interpretation was supported by the P-wave velocity models obtained from first-arrival tomography. Seismic data enabled us to map the bedrock surface with more details, determine the width of the bedrock fracture zones and the thickness of the weathered bedrock zone. New data also prove their utility in mapping glacial sediments, providing both the structural control and lithology distribution through the changes in P-wave velocity. We demonstrate that seismic data can be considered a great asset in 3D modelling of the buried valley’s aquifer system, reducing uncertainties introduced by conceptual models based on borehole data.