CHARMANT

The use of the subsurface is becoming increasingly important due to national energy policy goals and technological developments. In addition to traditional uses such as mining and groundwater extraction are being joined by new forms such as geothermal energy use and CO2 storage. This gives rise to a wide variety of conflict areas in urban areas between groundwater use and protection. The federal and state governments have recognized the need for underground spatial planning and have created some legal foundations for this. However, the practical relevance has not yet been investigated.

Although the EU Water Framework Directive formulates ambitious goals with regard to groundwater protection, the aspect of the thermal, chemical and ecological status of groundwater in urban areas has so far been insufficiently incorporated into spatial and urban planning.
A comprehensive assessment and prognosis of the ecological consequences of thermal and chemical changes in urban groundwater is hampered by the lack of appropriate modeling approaches. In addition, the extent to which existing planning instruments are suitable for incorporating groundwater status into urban planning and what regulatory obstacles exist hast to be examined.

In the supra-regional joint project CHARMANT, this problem is being addressed through interdisciplinary cooperation from the perspective of spatial planning, approval practice including their respective legal foundations and groundwater research for the first time.

The aim of the project is to develop a procedure for integrative groundwater management and the planning of groundwater use in complex urban areas, taking into account in particular the thermal influences on the groundwater ecosystem.

As case studies, the conditions in the cities of Berlin as Germany's most populous and largest city, and Karlsruhe as a typical German city in terms of area and population will be investigated.

As a result recommendations for action for groundwater management in these two cities, which should also be transferable to other urban areas are expected. Through environmental communication measures are intended to raise public awareness of groundwater protection and conflicts of use as a basis for greater involvement in planning processes and increasing the acceptance of administrative decisions.

The focus of the collaborative partners from the fields of geosciences, hydrology, ecology and engineering sciences is the development of ecological assessment approaches with the development of an automated monitoring concept for the dynamic conditions in urban groundwater.

The IOER is involved via the legal sciences and supports the project from a planning law and environmental law perspectives. Groundwater use and protection primarily raise questions of underground spatial planning, coordination with terrestrial spatial planning, urban land-use planning and specialist water law planning. Here the objectives of groundwater protection must be reconciled with traditional and new forms of the use of groundwater and the entire subsurface as well as climate adaptation requirements.

The aim of the legal sub-project is to provide concrete recommendations for the administration for the design of spatial and urban land-use plans within the framework of the existing legal possibilities.

Furthermore, it will be examined whether the legal framework meet the requirements for the compatibility of groundwater protection and underground uses are sufficient.