Groundwater Levels in Brandenburg, Germany: Interpolated Weekly Data from 217 Monitoring Wells

This dataset contains processed weekly groundwater level (GWL) time series from 217 monitoring wells across Brandenburg, Germany, covering the period 1991–2024. Original data was downloaded from the LfU Brandenburg Auskunftsplattform Wasser and interpolated using Piecewise Cubic Hermite Polynomials (PCHIP) (Fritsch and Butland, 1984; Virtanen et al., 2020) to create continuous time series for research applications. These files are used in the associated GitHub repository: https://github.com/marie202/GWL_and_Soil_Moisture. For detailed information, please refer to the provided README file. Key Information Data Source: Landesamt für Umwelt Brandenburg (LfU) (2025), Auskunftsplattform Wasser. Grundwasserstand (gesamt) [dataset], https://apw.brandenburg.de Temporal Coverage: 1991–2024 (22–35 years per well), weekly Data Format: CSV files ({WellID}_weeklyData_GW.csv) Columns: Date (YYYY-MM-DD), GWL (m a.s.l.) License: Data licence Germany – attribution – version 2.0 (dl-de/by-2-0) Contributor: Marie-Christin Eckert ([e-mail], ORCID: https://orcid.org/0009-0005-4003-6416) References Fritsch, F. N., & Butland, J. (1984). A method for constructing local monotone piecewise cubic interpolants. SIAM Journal on Scientific and Statistical Computing, 5(2), 300-304. Virtanen, P., Gommers, R., Oliphant, T. E., et al. (2020). SciPy 1.0: fundamental algorithms for scientific computing in Python. Nature Methods, 17(3), 261-272. Acknowledgments We acknowledge the Landesamt für Umwelt Brandenburg (LfU) for providing open access to groundwater monitoring data through their Auskunftsplattform Wasser portal.