BRGM Guadeloupe is located in Petit-Bourg, where, in addition to offices, it has an archive area open to the public and an instrumentation facility. The Division has a staff of about ten people including specialists in geology and its applications, natural hazards (volcanic, seismic, geotechnical, coastal), groundwater resources (quantity and quality) and the environment (waste management, circular economy).

In addition to the Guadeloupe region, BRGM's activities cover the French Overseas Communities (COM) of Saint-Martin and Saint-Barthélemy, as well as the archipelago of Saint-Pierre-et-Miquelon.

Public and private partners

BRGM has extensive experience of both public and private partnerships. It works 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: Prefecture, DEAL, DAAF, Regional or Departmental Councils, Water Office, ADEME, AFB, Agence des 50 pas Géométriques (Coastal Urban Planning Agency), University of the Antilles, CIRAD, INRA, ONF

Météo-France, OVSG, Guadeloupe Nature Park, ARS, Synergile competitiveness cluster, Géothermie Bouillante, Port Caraïbe, Communities of Communes, etc.

BRGM also occasionally works with private companies to develop methodologies for Research, Development and Innovation aimed at supporting their various fields of activity.

The challenges

Because of its geological origins and location in the Lesser Antilles volcanic arc, Guadeloupe is exposed to several risks. Due to its position along the subduction zone between the Atlantic and Caribbean plates, the area is exposed to the risks of volcanic eruptions, earthquakes and tsunamis. 

The mountain terrain that covers a large part of Guadeloupe is subject to major ground movements linked to episodes of heavy rainfall, among other things.

The islands' coastlines are exposed to swells coming from the north, to cyclones and tropical storm surges, as well as rising sea levels due to climate change, and are therefore extremely vulnerable to coastal flooding and erosion, which can seriously harm the natural environments and coastal infrastructures.

BRGM's involvement and responses

BRGM is involved in the C3AF Programme - in conjunction with the University of the Antilles, Météo-France and the University of Montpellier - which aims to measure the consequences of climate change on the French Antilles.

It is conducting several studies to improve knowledge about the different hazards linked to climate change and the geodynamic context.

BRGM helps draw up risk prevention documents (risk prevention plan, seismic microzoning, information maps, awareness raising campaigns, etc.), and is involved in crisis management activities (support for crisis units in the event of cyclones; RICHTER exercises: earthquake simulation; CARIBWAVE: tsunami prevention; ORSEC Volcano plan, including the development of pre-operational tools).

Since 2016, it has been running a coastline monitoring network whose aim is to document the changes to the coastline (historical data and updated data, with field measurements). The project initially concerned eight sites, but will eventually incorporate all the coastal front in the archipelago. It is laying the groundwork for development of a strategy for the responsible management of the Guadeloupe coastline.

Finally, the "CaribCoast" project, set up with English and Spanish-speaking partners in the Caribbean, aims to establish an international strategy for dealing with coastal risks.

And also:

• Audits and analyses in crisis situations.

The challenges

The islands in the Guadeloupe region do not all have the same availability of groundwater resources. The drinking water supply is mainly taken from rivers (70%) and springs (20%) located on the Basse Terre island. The remaining 10% comes from boreholes that exploit the groundwater resources on the islands of Grande Terre and Marie-Galante. The northern islands (St. Martin and St. Barthélemy) are considered to be "dry" islands. Currently, the drinking water there is produced by desalinating sea water.

Since the region is made up of islands, saltwater intrusion into the aquifers represents a major risk that could damage the quality of the resource. This means it is necessary to monitor the conductivity of the water in the various water masses of the archipelago on a daily basis.

Finally, the resources are significantly affected by historical pollution due to pesticides, such as chlordecone, particularly in the banana producing area (southern part of Basse-Terre). Since the residues of these products remain in the environment, finding alternative aquifers is now a priority for the region.

BRGM's involvement and responses

BRGM carries out piezometric monitoring of groundwater and publishes a bimonthly Hydrogeological Situation Report (BSH).  In accordance with the Water Framework Directive (WFD), it also monitors the chemical status of the groundwater masses in the Guadeloupe catchment basin.

BRGM is managing a comprehensive programme to increase knowledge of the aquifers and has already produced a hydrodynamic model of the Grande Terre aquifer. In recent years, an increasing number of surveys have been conducted on the volcanic island of Basse Terre, for which only a limited amount of hydrogeological information is available.

On Saint-Martin, BRGM has launched a major exploration project to find new underground resources.

Actions are also being implemented to better understand the interactions between groundwater, rivers and wetlands.

And also:

• A research programme studying agricultural pollution (organochlorine pesticides, in particular).

The challenges

Waste recycling is a major issue, particularly in island environments.

Today, the management of polluted sites and soils (due to widespread agricultural pollution) is a priority, notably through the "Chlordecone Plan". Past and present industrial activity has also resulted in significant risks in terms of the quality of the environment.

BRGM's involvement and responses

The major urban renovation programme launched in Pointe-à-Pitre has produced massive amounts of demolition waste, as well as a high demand for construction aggregates.

To encourage the recycling of this waste, BRGM has drafted a Guide to recycling and using inert waste in the construction industry.

With regard to environmental pollution (in particular due to organochlorine pesticides), BRGM has implemented several measures:

• the creation of an Observatory of Agricultural Pollution in the Antilles (OPALE) in conjunction with research teams from CIRAD, INRA and IRD;
• the ERDF RIVAGE project, in partnership with CIRAD, INRA and the University of the Antilles, whose objective is to set up a system for assessing and supporting innovations in agriculture in order to improve the quality of the environment and agricultural products; 
•  an inventory of more than 600 potentially polluted sites in peri-urban areas. The aim is to map the chlordecone contained in the soils around the archipelago and create a database that can be used for future projects (rehabilitation, restoration, new developments, etc.).

And also:

• Contribution to the Regional Health and Environment Plan
• Emergency responses to accidental pollution (e.g. oil pollution in the municipality of Goyave, including tracking the origin/Water Police)

The challenges

Improving geological knowledge is a major priority for BRGM.

Indeed, the establishment of a comprehensive set of basic data is essential for research work as well as for applications linked to mineral resources (quarries), geothermal energy, the natural geological heritage, but also to geological risks (ground movements, earthquakes) and groundwater resources.

BRGM's involvement and responses

A recent airborne geophysical survey (GUADEM) that covered the entire archipelago area has made it possible to develop a regional data infrastructure that can identify potential mineral resource zones (aggregate quarries in Guadeloupe), map saltwater intrusions (Marie-Galante) and identify areas that could be subject to land movements.

For the purposes of the French Geological Reference Platform (RGF), BRGM is currently updating the geological map of Basse Terre at a scale of 1: 50,000 (that can be used by all the different stakeholders).

BRGM is also involved in setting up the Geothermal Energy Centre of Excellence (notably by creating a training course in geothermal energy technology and techniques). The Caribbean has significant potential in terms of high-enthalpy geothermal energy, with the possibility of building power plants in the region, particularly in Dominica.

And also:

• Prospecting for rock deposits; work on unregistered quarries; preparation of a Regional Quarry Plan.
• Involvement in the future Antilles Geological Reference Platform (RGF).