The EU-funded Franco-German project is investigating groundwater development in the central and southern Upper Rhine Rift Valley in the past, present, and future. Under the auspices of the French authority BRGM (Bureau de Recherche Géologique et Minière) and with significant participation from LUBW (Landesanstalt für Umwelt Baden-Württemberg), the project focuses on modeling groundwater volumes and water levels. 
Furthermore, in the “Biodiversity” project module on the German side, KIT-IfGG is working on the question of how groundwater developments affect habitats. This question is being investigated in parallel in Alsace by the University of Strasbourg (Laboratoire LIVE). In Baden, the focus is on long-term changes in wetlands and water bodies on the lower terrace. These are likely to be particularly affected by changes in the regional landscape water balance and are not influenced by the supraregional groundwater influence of the Rhine.

Indicators of changes in habitats include groundwater levels, which were measured at the sites using groundwater pressure probes.

The actual effects are particularly evident in the composition of the flora of wetland habitats, for which comparative studies are being conducted over as long a period as possible. The project began with a complex search for reliable historical vegetation data (1950s to 1980s).

The areas were re-examined as repeat surveys in 2024 and 2025, as close as possible to these locations, in order to be able to analyze the changes over the decades in a direct comparison.

Natural sites without further human influence could rarely be documented with historical photographs, but some alder swamp forests still exhibit very natural conditions today.

By far the most data points were found and recorded in damp and wet grasslands. These habitats have become much rarer today due to the intensification of agricultural use and urban development, and are often only found in nature reserves. Plants are good indicators of ecological changes in locations: their so-called indicator values and other species-specific characteristics are used to draw conclusions about the causes of change in locations using statistical evaluations. The factor of groundwater is central to this, but other factors, especially those related to land use, have also significantly changed the sites. Groundwater depletion due to drainage is one cause, but significant changes have also been found even where groundwater levels have remained constant. These changes may be due, for example, to greater nutrient availability (nitrogen fertilization), intensification of land use, or even abandonment of land use.

The project is funded by the Baden-Württemberg Ministry of the Environment via the Karlsruhe Regional Council, Ref. 52.

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