West Africa faces major challenges in water resources management. In this region, marked by extreme climate variations and increasing pressure on the water tables, sustainable groundwater management has become a must.

The Senegal-Mauritania Aquifer System (SMAS), one of the largest transboundary aquifers in Africa, constitutes a strategic resource for the populations of Senegal, Mauritania, Gambia, and Guinea-Bissau.

Faced with threats related to overexploitation, pollution, and climate change, these countries have embarked on an innovative approach to transboundary cooperation for the preservation and sustainable management of this vital resource. The SMAS project, led by the Sahara and Sahel Observatory (OSS) and funded by the Global Environment Facility (GEF) and the United Nations Environment Program (UNEP), is being implemented within the framework of such an approach. 

It aims to provide countries with a framework for consultation on aquifer management, through the improvement of knowledge, a Transboundary Diagnostic Analysis (TDA) and a Strategic Action Program (SAP).

The Regional Working Group (RWG): A key body for shared governance

Created to foster dialogue between the countries and ensure coordination of the SMAS project activities, the Regional Working Group (RWG) that includes representatives from the ministries of water, hydrogeological experts, and river basin Organizations such as OMVS and OMVG, is a key component of this dynamic.

The RWG's primary mission is to align water management strategies and promote joint governance of the SMAS water resources. It provides a consultation framework where countries share their knowledge and experiences and define joint actions for sustainable aquifer exploitation.

" Water knows no boundaries. We need to ensure a sustainable future for our people, we must think and act together "

A training and consultation session was held in Mauritania from February 17 to 21, 2025, bringing together members of the RWG, hydrogeological experts, and technical partners. This workshop provided an opportunity to share information on ongoing and planned initiatives in the Aquifer Basin, build country capacities, and lay the foundations for a shared vision for the future of the SMAS. 

Transboundary Diagnostic Analysis: A Tool for anticipation and action

One of the key outcomes of this cooperation is building the stakeholders' capacities in Transboundary Diagnostic Analysis and the formulation of the Strategic Action Program, a GEF process for international water management. This TDA/SAP tool aims to identify major issues affecting the aquifer, such as:

• Overexploitation of groundwater, threatening its natural renewal;

• Pollution risks due to industrial and agricultural activity;

• The impacts of climate change on aquifer recharge;

• The vulnerability of the populations who rely on this resource.

The TDA provides the scientific and technical basis for developing the Strategic Action Program, a planning document that will define concrete actions for the preservation and sustainable management of the SMAS

A dynamic of strengthened cooperation

Here follow some of the major advances from the RWG efforts and the SMAS project: i) A strengthened institutional framework, with the active involvement of river basin management Organizations and relevant ministries; ii) An increased commitment from international partners, particularly the World Bank, which supports capacity building for local stakeholders; iii) An improved scientific knowledge, through the alignment of databases and the development of hydrogeological modeling tools; iv) A strong political will from Member States to establish sustainable governance mechanisms, ensuring the sustainable use of the resources.

Involving communities: a key issue for the sustainability of the actions

Beyond the scientific and institutional aspects, one of the fundamental challenges of the SMAS management is the involvement of local populations. The communities living in the affected areas are the first to suffer the consequences of pressures on groundwater and must therefore be involved in decision-making.

" The life of our people depends on these water resources. It is crucial to have them involved in every stage of the process, because they are the first to be affected by the changes we are implementing."

Thus, awareness-raising actions, training and community consultations will be carried out in order to promote local ownership of management measures and ensure their long-term effectiveness.

Future prospects and commitments

The efforts made so far lay the foundations for coordinated and sustainable management of the Senegal-Mauritania Aquifer System. Next steps include:

• The Transboundary Diagnostic Analysis of the Strategic Action Program (SAP), which will define state commitments and priority investments;
• A sustainable institutional mechanism under the aegis of a regional structure such as the OMVS or the OMVG;
• Monitoring and decision-making tools, integrating hydrological models and shared data platforms;
• The commitment of the SMAS countries and their partners to this approach illustrating a collective awareness: water resources management can only be effective if it is based on cooperation and regional solidarity. Thanks to the RWG and the initiatives led by the OSS, a new era of shared water governance is underway in West Africa. Back in the day, we had an invisible resource beneath our feet, now it is becoming a strategic lever for the development and water security of the region.

About the project: 

The Strengthening the sustainable management of the Senegalo-Mauritanian Aquifer System to ensure access to water for populations facing climate change - SMAS aims to promote cooperation between four countries (The Gambia, Guinea-Bissau, Mauritania and Senegal) and build the institutional capacity for the protection and sustainable management of the Senegalo-Mauritanian Transboundary Aquifer in order to improve water and food security and resilience to climate change.

For more information, please contact:  Mohamedou Sy, Director of the Water Department at OSS: lamine.babasy@oss.org.tn  or Lilia Benzid, Communication Expert at OSS : lilia.benzid@oss.org.tn.

Related content: https://www.oss-online.org/en/smas

Words by Mohamedou Baba Sy and Lilia Benzid. Photo cover: Well in the Saint Louis region, Senegal by Andrea Borgarello.