Grand Est (Eastern France)
Geological map of Grand Est (Eastern France).
BRGM Grand Est has its regional head office in Nancy, as well as regional delegations in Reims and Strasbourg. The Division has a staff of 20 people working as a network, with 10 people based in the regional head office and a further 5 employees in each delegation.
At the crossroads of Europe
The Grand Est region comprises ten départements (Ardennes, Aube, Marne, Haute-Marne, Meurthe-et-Moselle, Meuse, Moselle, Bas-Rhin, Haut-Rhin, Vosges) and covers 57,000 km², encompassing the former regions of Champagne-Ardenne, Alsace and Lorraine. It is the only region in France that borders four countries (Germany, Belgium, Luxembourg and Switzerland). With a population of 5.5 million inhabitants, the Grand Est region has several major conurbations: Strasbourg Eurométropole (home to the headquarters of several European institutions), Grand-Reims, Troyes-Champagne-Métropole, Mulhouse-Alsace-Conurbation, Grand-Nancy and Metz-Métropole.
The Grand Est region has a highly diversified economy, with numerous competitiveness clusters, laboratories and centres of excellence in the fields of chemistry, materials, eco-technologies and renewable energies, and a vibrant agri-food industry. The region also has a long industrial and mining history, whose legacy needs to be managed today.
The region has set out its spatial-planning and economic objectives in the "Regional Master Plan for Economic Development, Innovation and Internationalisation" (SRDEII) and the "Regional Master Plan for Spatial Planning, Sustainable Development and Territorial Equality" (SRADDET), to which BRGM contributes its expertise in its core areas of specialisation.
Public and private partners
BRGM has extensive experience of both public and private partnerships. We work on projects to help shape public policy, or for public and private research in response to industrial requirements, as well as training projects aimed at every level of spatial planning and decision-making in the region. It conducts its operations within the scope of:
- framework agreements: Rhine-Meuse Water Agency, Strasbourg Eurométropole, University of Lorraine, Greater Reims Urban Community Council;
- partnerships with organisations: GIP GEODERIS (post-mining operations), Scientific interest group on industrial wasteland sites (GISFI), Ecopôle Lorraine Friches Industrielles (ELFI) cluster, HYDREOS competitiveness cluster;
- contractual agreements: decentralised government departments (DDT, DREAL, ARS, Vosges Mountains Spatial Planning Commission), specific agencies (ADEME, French Biodiveristy Agency, Haut-Rhin Tourist Development Agency, Établissement Public Foncier Lorrain (EPFL)), local authorities (Grand Est Regional Council, communities of conurbations of Châlons-en-Champagne, Reims, Troyes, Metz, Mulhouse and Nancy, etc.), trade federations (Alsace water syndicate (SDEA), Mulhouse water syndicate, etc.).
References and projects
Geology and natural hazards: adapting to climate change
Climate change will have an impact on the frequency and intensity of extreme weather events: land movements linked to droughts, river flooding, storms, larger quantities of pollutants released into the natural aquatic environment, etc. For example, an increase in winter rainfall could lead to more frequent and violent storms. Mudslides and flooding due to the run-off of water could become more regular and intense. To help regions become more resilient to extreme weather events, we need to improve our understanding of these phenomena and the vulnerability of different areas.
3D representation of chalk quarries in Châlons-en-Champagne (Marne).
BRGM's involvement and responses
The increasing regularity of extreme phenomena (intense droughts followed by periods of heavy rainfall) could destabilise areas that were previously not particularly vulnerable to land movements. Consequently, prevention programmes and maps need to be constantly reviewed and updated, drawing on the significant progress that has been made in terms of our understanding of various geological phenomena, investigation techniques (LIDAR, satellite interferometry, geophysics) and hazard and risk assessment.
Location of the most significant land movements:
- subsidence and collapse of war-time galleries and tunnels on the 1914-1918 front and in Mulhouse, in the chalk and underground quarries in Champagne-Ardenne and Lorraine and in former beer-brewing cellars in Strasbourg;
- mudslides in Champagne-Ardenne and Alsace;
- landslides affecting scarp slopes (the cuesta of Ile de France in Champagne-Ardenne, and the cuesta of Moselle in Lorraine);
- rockfalls in the Ardennes hills and the Vosges mountain range;
- subsidence and collapse of karstic cavities on the limestone plateaux of Champagne-Ardenne and Lorraine;
- land movements linked to the dissolution of certain characteristic mineral phases of the subsurface (levels of potash or salt);
- more rapid erosion of slopes due to faster run-off rates (for example vineyards);
- land movements linked to certain characteristic mineral phases of the subsurface in Champagne-Ardenne and Lorraine.
In order to ensure balanced regional development, it is also essential to acquire and maintain up-to-date knowledge of the subsurface and disseminate this information to the broadest possible audience. The Cavity and Land Movement databases - accessible via the Géorisques portal - are crucial tools for managing risks, particularly as regards underground cavities, which can be a major threat to people and property if they collapse.
Natural resources: monitoring and protection of groundwater
Agricultural pollution (nitrates and pesticides) is a major problem as regards water quality in Champagne-Ardenne and also in Alsace, where the Rhine water table, which is not very far below the surface, is very vulnerable. Industrial pollution is common in the areas that were heavily involved in the iron and steel industry (Meuse valley in the Ardennes, the Fensch valley in Moselle) or petrochemical production (Alsace plain), as well as in large conurbations with a strong industrial past (Strasbourg, Troyes, etc.).
There are three specific types of pollution in the Grand Est:
- chloride pollution (salt mines in Lorraine and potash mines in Alsace). In Lorraine, this led to a Master Plan for Drinking Water Supply being implemented for Metz, Nancy and Thionville. In Alsace, this type of pollution is monitored by BRGM;
- sulphate pollution in the water reservoirs of old mines (a resource which is accessible and which replenishes itself, representing around 500 million cubic metres of water) in the iron-ore basin. BRGM monitors and models changes in sulphate levels;
- pollution linked to the First World War. Recent studies have highlighted pollution (perchlorates, arsenic, etc.) along the front line and near shell destruction sites.
We can also note the increasing level of micro-pollutants (drug residues, nano-particles, heavy metals, solvents) from several different economic activities, which need to be monitored so as to track developments and trends in the coming years.
As regards quality, despite a general abundance of groundwater, certain valleys in the upper section of the basin (Vosges massif, etc.) suffered from a lack of drinking water during the droughts of 2003, 2011 and 2012. BRGM, the Rhine-Meuse Water Agency, the Grand Est Region, the Vosges Mountains Spatial Planning Commission and several university laboratories are currently working together on a comprehensive survey to establish a more accurate picture of the water resources in the Vosges mountain range and assess the impact climate change may have on these resources.
Water is also extracted on the limestone plateaux (chalky Champagne area, Brie, etc.) and this can sometimes lead to water courses drying up across larger areas and for longer periods. It is therefore important to have a better understanding of the relationships between rivers and water tables to improve the state of the region's water masses.
Conceptual model of water table rises in the Troyes conurbation (Aube).
BRGM's involvement and responses
BRGM manages the piezometric observation networks for all the aquifers, except for the Rhine aquifer, and publishes information about their state on two websites (Rhine-Meuse basin: SIGES Rhine Meuse; Rhine aquifer: SIGES Rhine Aquifer), with real-time data incorporated from the end of 2018.
The water-quality studies cover various sources of pollution: agricultural, industrial and emerging pollutants.
As regards agricultural pollution, the studies aim to characterise nitrate and pesticide pollution (in terms of concentrations and how they are transferred from the soil to the water resources) and to understand exactly where these compounds come from.
Due to the presence of several types of industry in the area, and the vulnerability of the Rhine water table, industrial pollution is a real problem in Alsace. The main pollutants are chlorinated solvents and hydrocarbons.
The emerging pollutants studied are drug-related substances and pollutants from firearms/explosives (perchlorates) linked to the First and Second World Wars.
The sector-based studies carried out by BRGM aim to characterise the extent of the pollution and to determine its possible (or proven) origins.
Hydrogeological models are used to predict changes (quantity and quality) in the groundwater:
- model of the Lower Triassic Sandstone (LTS) aquifer at regional and local levels (changes in the LTS aquifer in the Vittel region and resource management scenarios);
- hydrological and chemical simulator of reservoirs in flooded mines in the Lorraine iron basin (changes in water quality, and particularly sulphate content).
Renewable energy and energy transition: geothermal energy
The policies of the Grand Est region aim to increase the share of renewable energies in the energy mix.
The geothermal potential of the Rhine Graben (Alsace) has been known for a long time and is being exploited experimentally for electricity production at the EGS (Enhanced Geothermal Systems) site in Soultz-sous-Forêts.
Elsewhere in the region, the main aquifers have great potential for producing very low-enthalpy (< 30°C) or even low-enthalpy (< 100°C) geothermal energy.
Moreover, the production of solar and wind power (which are intermittent in nature) requires the development of underground storage technologies.
EGS pilot geothermal plant at Soultz-Sous-Forêts (Bas-Rhin).
© BRGM - Albert Genter
BRGM's involvement and responses
Assessment of deep reservoirs: several research projects – such as CLASTIQ2, GEFRAC, TECITUR, or GEORG – aim to improve our knowledge of the geothermal resources and how the deep geothermal reservoirs function in the Rhine Graben and in the deep aquifers of Western Champagne-Ardenne. The research draws on mechanical, hydrogeological and thermal modelling, in particular.
Assessment of geothermal potential and energy storage: several studies into the thermo-hydrochemical behaviour of reservoirs in flooded coal or iron mines are being conducted to assess their geothermal storage potential.
Risk management: the development of geothermal projects also requires good risk management. BRGM has mapped the region's high-risk areas in terms of minimum-impact geothermal applications and aims to develop detailed maps for certain conurbations. It is also important to provide decision making tools to help manage and assess the impact of developing very low-enthalpy geothermal energy, particularly on the Alsace water table in the vicinity of Strasbourg Eurométropole.
Eco-technologies and sustainable urban planning: management of polluted sites and land
The closure of mining, steel and chemical plants has left large areas of land in a poor state. Today, it is important to reclaim this land in order to limit the need to develop new areas. Original, multi-level and multi-disciplinary approaches are needed to develop strategies to manage and clean up soil and groundwater pollution:
- laboratory analyses to characterise and quantify the bio-geochemical processes responsible for transforming and transporting the pollutants;
- development of site-specific strategies based on our understanding of these processes.
Reducing the presence of micro-pollutants requires an approach that focuses on the specific setting (impact studies) rather than just the type of waste (emission standards).
3D mapping of the chemical quality of soils at the Micheville site (Lorraine).
BRGM's involvement and responses
To manage industrial wasteland effectively, you need to know a site's industrial past. BRGM has produced historical inventories of former industrial sites and service activities (IHR) for each département, which can be consulted in the BASIAS database.
For Strasbourg, Metz, Nancy and Reims, these will be supplemented by historical urban inventories (IHU), on a plot-by-plot scale.
Several projects are in progress:
- definition of a method to prioritise wasteland for development in Alsace. This approach will then be extended to the entire Grand Est region;
- application of the national TERRASS methodology for the responsible reuse of excavated earth in Lorraine (on steel-industry and mining wasteland);
- assessment of the state of the area and risks, the transport of pollutants, the physico-chemical decontamination processes, as well as the requalification of polluted sites and soils (Scientific interest group on industrial wasteland sites/GISFI);
- deployment of innovative decontamination solutions on the site of a former coke plant in Moselle (BIOXYVAL project, Écopôle Lorraine Friches Industrielles (ELFI) cluster);
- identification and analysis of the sources and behaviour of munitions compounds (such as perchlorates) in the groundwater of the Champagne chalk area: research project in collaboration with the University of Reims, the Seine-Normandy Water Agency and the Regional Health Agency.