The Saxon State Office for the Environment, Agriculture and Geology publishes a wide variety of hydrological data such as groundwater levels and flood data.
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If the data or data derived from these data are used for presentation, information or publication purposes, the origin of the data must be indicated in a clearly visible place in every presentation and on every representation, such as: "Presentation based on data from the Saxon State Office for the Environment, Agriculture and Geology". Any liability for damages of any kind resulting from the transfer, use and further processing of the data is excluded. The LfULG assumes no liability or guarantee for the accuracy or completeness of the information provided.
See https://www.wasser.sachsen.de/karten-und-gis-daten-4456.html#article6047 and https://www.smul.sachsen.de/rechtliche-hinweise-5266.html