The quaternary formations in the Wielkopolska region consist of glacial and water-glacial deposits formed during three glacial and two interglacial periods. These sediments are located on a much diversified Tertiary surface composed of Upper-Miocene mottled loams. In hydrogeological terms, the region is located in the macro-region of the Polish Lowland, in the sub-region of the Zielona Góra and Leszno upland.

The aquifer used by the HERMES water intake is situated in a direct and indirect protection zone and belongs to a quaternary sub-clay aquifer dating back to the Southern-Polish Glaciation. It has the form of well sorted sandy deposits, and in the top levels fine deposits are found – silts, powdery sands and clays of the Central-Polish Glaciation.

Because of their extensive range, free water table and excellent alimentation, the waters do not require any kind of treatment and their physicochemical and bacteriological composition meets the requirements of Polish and EU law.